Prevalence and Clinical Characteristics of Charles Bonnet Syndrome in Patients with Glaucoma

Prevalence and Clinical Characteristics of Charles Bonnet Syndrome in Patients with Glaucoma | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Prevalence and Clinical Characteristics of Charles Bonnet Syndrome in Patients with Glaucoma Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6566184/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 26 Aug, 2025 Read the published version in International Ophthalmology → Version 1 posted 12 You are reading this latest preprint version Abstract Aims and Background: Charles Bonnet Syndrome (CBS) is characterized by visual hallucinations in individuals with acquired vision loss. Despite its potential impact on the patient’s quality of life, CBS remains underdiagnosed and is often misinterpreted as a psychiatric illness. This study aims to investigate the prevalence and clinical characteristics of CBS in patients with glaucoma, also highlighting its correlation with visual acuity and severity of glaucoma. Methods : A cross-sectional study was conducted on 200 patients diagnosed with glaucoma at a tertiary care center of western India. Patients were evaluated for CBS using a pre-designed questionnaire capturing demographic data, glaucoma profiles, and details about hallucinations. Statistical analysis was performed to ascertain the prevalence of CBS and its associations. Results : CBS was identified in 23 patients, resulting in a prevalence of 11.5%. Most affected individuals were aged 50-59 years, with a male-to-female ratio of 11:12. Most patients experienced simple visual phenomena, such as lines and light flickers. CBS was more prevalent in primary open-angle glaucoma (69.57%) compared to primary angle-closure glaucoma (30.43%). A significant proportion of patients reported that their hallucinations affected their emotional well-being and quality of life. Conclusion : This study underscores the prevalence of CBS in glaucoma patients, even among those with relatively good visual acuity. Recognizing CBS is crucial for appropriate management and support, as it significantly impacts the psychosocial health of patients. Increased awareness and education for both patients and clinicians are essential to ensure improved patient outcomes in overall glaucoma care. Clinical significance: Despite its potential impact on the patient’s quality of life, CBS remains underdiagnosed and is often misinterpreted as a psychiatric illness. It can occur even among those with relatively good visual acuity and can significantly affect the emotional well-being and quality of life of patients. Timely detection and patient counselling may help to minimize the negative consequences of this condition. INTRODUCTION Charles Bonnet syndrome (CBS) is a condition characterised by visual hallucinations in patients who have acquired vision loss affecting the eye or visual tracts in the optic nerve, chiasm, or brain. Often referred to as release hallucinations, these visual phenomena can vary from basic, unstructured forms like lines, flashes of light, or geometric patterns to intricate, detailed images depicting people, animals, or entire scenes[ 1 ]. The most widely recognized explanation suggests that these hallucinations arise when the loss of visual sensory input leads to disinhibition in the visual cortex, causing it to activate spontaneously[ 2 , 3 ]. Originating from the visual cortex to the eyes, CBS can arise due to any condition impacting the visual pathway[ 4 ]. Its common aetiologies are Diabetic retinopathy, Age-related macular degeneration, Cerebral infarction, Cataract, Glaucoma, Optic neuritis, Retinitis pigmentosa, Temporal arteritis, Central retinal artery occlusion and Retinal vein occlusion [ 5 ]. CBS typically occurs in patients whose visual acuity is below 0.5 in decimal terms, equivalent to Snellen measurements[ 6 ]. Patients with severe glaucoma may have considerable ganglion cell loss, which can lead to physiological deafferentation and increase their chance of developing CBS [ 7 ]. Patients with glaucoma may experience CBS more frequently than is typically recognized. The prevalence of CBS was found to be 20 percent among patients with glaucoma attending a visual rehabilitation program [ 8 ]. While hallucinations are not always functionally debilitating, they can be disturbing for patients and have a detrimental influence on their quality of life including but not limited to emotional distress and social stigma [ 9 ]. Based on published case reports, this condition is poorly understood by healthcare professionals and is often mistaken for psychosis or an early phase of dementia[ 10 ]. Patients often do not disclose visual hallucinations because they believe they are signs of a mental illness [ 4 ]. There is no universally accepted treatment for CBS however in some cases, when the underlying vision impairment was treated, the hallucinations were frequently resolved [ 11 , 12 ]. Increased visual stimulation through rapid eye movements or increased arousal such as social interactions or activities have been known to reduce the hallucinations. [ 13 , 14 ] We conducted this study with the aim of studying the prevalence and visual characteristics of CBS and comparing the characteristics of CBS with the severity of glaucoma. METHODOLOGY Following the approval of the Institutional Ethics Committee, the study was conducted over 2 months from February 2024 to April 2024. 200 patients were enrolled by convenient sampling in this cross-sectional study as per the inclusion and exclusion criteria from the Department of Ophthalmology of a tertiary care center. The patients aged 18 and above diagnosed with glaucoma, with an absence of any other visual problems apart from glaucoma, and who gave written consent to be a part of the study were included. Patients diagnosed with mental illness, suffering from cognitive impairment, or any drugs likely to impair cognitive, emotional, or psychological functions were excluded from the study. Patient awareness and clinical presentation of all the former types of patients of the Ophthalmology Department, during the allotted time for research, was recorded in a pre-designed Questionnaire (Annexure I) [ 15 ] which contains all the necessary details of the concerned patient including his/her demographic details along with investigations such as the best corrected visual acuity, gonioscopy, perimetry inference (in the patients in whom it was possible, considering the visual acuity) and type and severity of glaucoma. The questionnaire was validated by pilot testing on 20 patients who were not included in the analysis. The data was collected securely through Google Forms. The patients were asked the questions translated into their vernacular language by the investigators, who were fluent in that particular language, and the data was filled in by the investigators on behalf of the patient. The diagnosis of glaucoma was made based on the findings of gonioscopy, broadly categorized into open angle glaucoma and closed angle glaucoma. Visual acuity as well as visual field were obtained via objective correction and perimetry respectively. The patients were asked about the nature of their hallucinations, their duration, onset, and frequency, aggravating and relieving factors as well as their effect on their routine and mental well-being. The questions were asked in their native language (Gujarati or Hindi) and were filled in by the researcher. Data was entered in an Excel sheet and statistical analysis was conducted using the inbuilt functions of Excel and appropriate statistical software. RESULTS A total of 200 patients were included as per the inclusion and exclusion criteria in the study. The findings of CBS were positive in 23 patients, signifying a prevalence of 11.5%. The male-to-female ratio was 11:12 with a majority of the patients being between 50-59 years (Table-1). TABLE-1: AGE DISTRIBUTION OF PATIENTS SUFFERING FROM CBS AGE GROUP (years) FREQUENCY 30-39 2 40-49 2 50-59 8 60-69 7 70-79 3 >80 1 Most of these patients (11) reported that the onset of hallucinations was from the past 6 months while 5 patients were observing hallucinations for 6-12 months and 7 patients for more than a year. Fourteen patients (60.87%) attested to having a daily occurrence of hallucinations, 8 patients (34.78%) had a weekly occurrence and one patient (4.35%) reported a hallucination once a month. Two patients were illiterate, four had studied up to 10 th grade and one patient had completed higher secondary education. Out of the 23 patients suffering from CBS, two patients held a graduate degree or higher. Out of the 23 patients who experienced hallucinations, 16 patients (69.57%) were cases of primary open angle glaucoma while the remaining 7 patients (30.43%) were diagnosed to have primary angle closure glaucoma (Table-2). TABLE-2: FREQUENCY OF HALLUCINATIONS AND TYPE OF GLAUCOMA DIAGNOSIS EVERY DAY EVERY WEEK EVERY MONTH TOTAL Primary angle closure 4 3 0 7 Primary open angle 10 5 1 16 The binocular corrected visual acuity as measured by Snellen’s chart was found to be 6/6 in ten patients, and 6/9 in four patients. One patient each had visual acuities of 6/12, 6/18, 6/24, 6/60. Only hand movements were perceived by two patients and one patient could decipher fingers at a distance of 3 meters (Table–3). Perimetry interpretations were as mentioned in table-4. TABLE-3: VISUAL ACUITY AND FREQUENCY OF HALLUCINATIONS Visual Acuity Incidence Frequency Every day Every week Every month Right Eye 6/6 10 6 4 0 6/9 4 3 1 0 6/12 1 1 0 0 6/18 1 1 0 0 6/24 1 1 0 0 6/36 1 1 1 0 6/60 1 0 0 1 HM, PL, PR 2 0 2 0 No PL 1 1 0 0 CF 0 0 0 0 Left Eye 6/6 10 5 5 0 6/9 4 4 0 0 6/12 1 1 0 0 6/18 0 0 0 0 6/24 1 0 1 0 6/36 2 1 1 0 6/60 1 1 0 0 HM, PL, PR 2 2 0 0 No PL 0 0 0 0 CF 2 0 1 1 TABLE-4: FREQUENCY OF HALLUCINATIONS WITH RESPECT TO PERIMETRY FINDINGS Scotomas Frequency of hallucinations (Right eye) Frequency of hallucinations (Left eye) Every day Every week Every month Total (n=23) Every day Every week Every month Total (n=23) Superotemporal 0 0 0 0 2 0 0 2 Inferotemporal 1 0 0 1 1 0 0 1 Supero and inferotemporal 0 0 0 0 0 1 0 1 Superior arcuate 1 0 0 1 1 0 0 1 Inferior arcuate 2 1 0 3 0 0 0 0 Superior and inferior arcuate 1 2 0 3 2 2 0 4 Central 0 0 0 0 1 0 0 1 Superior and inferior arcuate and central 4 0 0 4 3 0 0 3 Double arcuate and paracentral 5 2 1 8 2 4 1 7 Normal 1 2 0 3 2 1 0 3 Five patients reported the occurrence of hallucinations prior to their visual deterioration whereas fifteen patients were affected after the development of significant visual defects: the rest stated simultaneous occurrence of hallucinations and visual impairment. The nature of hallucinations was not limited to a few specific types. A wide range of hallucinations were reported as shown in Table-5 lasting for a few seconds (eleven patients), a few minutes (ten patients), a few hours (one patient), or perennially (one patient). Twenty-one patients (91.3%) perceived the images to be real and twenty patients (86.96%) felt that the hallucinations were clearer than their actual vision. One patient also reported incidences of seeing images of dead people. The hallucinations were primarily monochromatic i.e. black and white (78.26%) with three patients (13.04%) reporting seeing hallucinations with a few specific colours and two patients (8.69%) having polychromatic hallucinations. Thirteen (56.52%) patients experienced mobile hallucinations while the others experienced stationary ones. TABLE-5: NATURE OF HALLUCINATIONS TYPE OF HALLUCINATION FREQUENCY Lines 12 Dots 12 Light Flickers 5 Landscapes 0 Shapes 1 Animals/Insects 2 Trees 0 People 2 Faces 3 Tapestry 0 Other unusual perception 0 The hallucinations occurred periodically with three patients each having the episodes on waking up and when they are awake, one patient each reporting the occurrence in the afternoon, morning and evening, and while reading; the rest thirteen cases had the episodes anytime during the day. The images were rarely accompanied by other sensations such as altered taste as was reported by two patients. Only one patient experienced the images attempting to communicate (talk) while twenty-one patients reported feeling as though the images were trying to touch them. Seventeen patients often suffered from the episodes in solitude while one patient reported seeing images exclusively when alone. Fifteen people saw the images when at home. The hallucinations were reported to occur when patients were in a calm and relaxed state, often while concentrating on a specific activity, as noted by eighteen individuals. Often, the patients attempted some strategies with varying degrees of success to make the images disappear such as blinking their eyes (43.48%), carrying out a distracting activity (17.39%), closing their eyes (34.78%), or washing their face (8.69%). While the images did not appear threatening, as was the case in twenty patients, they did have a negative effect on the mood and quality of life. Fourteen patients (60.87%) complained of worry and anxiety on seeing the hallucinations. Eleven patients were now habituated to the hallucinations while the rest were still coping with the episodes. Eleven patients had also consulted a medical professional for these hallucinations. However, these were with lower levels of education. DISCUSSION Visual hallucinations in individuals with acquired vision impairment affecting the eyes or visual pathways are characteristic of Charles Bonnet syndrome. Commonly mistaken as a psychiatric illness, it can have a significant psychosocial impact on patients particularly leading to anxiety and distress related to visual hallucinations. There is immense variability in the type, frequency, and emotional impact of CBS hallucinations indicating that the management of the disorder should be tailor made for each individual. Improved recognition of CBS can lead to early diagnosis and appropriate management of the disorder, hence reducing patient distress. Our study aimed to investigate the prevalence and characteristics of Charles Bonnet Syndrome (CBS) among patients with glaucoma. The findings revealed a CBS prevalence of 11.5% among the 200 patients included, which aligns with the existing literature by Jan T et al. [ 16 ] and Jacob A et al. [ 10 ] on the occurrence of visual hallucinations in patients with significant visual impairment, particularly those with glaucoma. Our study population had an almost equal gender distribution, with a slight female predominance (male to female ratio of 11:12). The age distribution showed that most patients experiencing CBS were between 50–59 years, which is consistent with the age-related nature of visual impairment and the development of CBS. In the study by Jacob A et al., it was stated that the syndrome occurs most commonly in elderly people, probably because of the prevalence of visual impairment in this group [ 10 ]. Surbhi Y et al. also reported female predominance amongst a CBS prevalence of 13.5% similar to our findings of a prevalence of 11.5% with a higher female affection (12:11). [ 8 ] Surbhi Y et al. [ 8 ] found that certain factors such as higher age, female gender, reduced contrast sensitivity and not living alone, in addition to low vision, could predispose to CBS; a finding also corroborated with Jackson ML et al. [ 17 ] and Gordon KD [ 18 ]. Taking our findings into account, we found that CBS may not be rare in elderly patients with varying degrees of glaucoma, with or without other ocular comorbidities. In terms of the types of glaucoma, a higher prevalence of CBS was observed in patients with primary open-angle glaucoma (POAG) (69.57%) compared to primary angle-closure glaucoma (PACG) (30.43%). This is in line with prior studies such as Peters D et al. [ 6 ] where out of 337 adult patients with open –angle glaucoma, 7.1% presented with CBS.. This probably indicates a greater correlation of CBS with POAG, possibly due to the more progressive visual field loss associated with this condition. Visual acuity measurements revealed that CBS can occur across a range of visual acuities, though a majority of the affected patients had a visual acuity of 6/6 in either or both eyes. Our study found that patients with varying degrees of visual acuity, including those with mild visual impairment, also experienced CBS, which supports the findings of Jacob A et al. of CBS in patients with relatively good visual acuity [ 10 ]. This coincides with our observation where almost 52.6% of subjects with normal visual acuity presented with CBS. This differs from the findings of Scott IU et al., who identified a link between reduced visual acuity and the occurrence of CBS [ 9 ]. In their research, 86 patients from the Wilmer Ophthalmologic Institute Retinal Vascular Center were assessed, showing a 15.1% prevalence of visual hallucinations. Their univariate analysis indicated that factors strongly linked to hallucinations included being female, having poor visual acuity, bilateral vision loss, emotional distress, diminished functional ability, and a lower quality of life. Tan CS et al. noted that in patients with relatively good visual acuity, the prevalence of CBS was between 0.4% and 2% [ 19 ]. Conversely, in those with poorer visual acuity, prevalence rates ranged from 11–12.3%. These findings indicate that reduced visual acuity may contribute to a higher likelihood of developing CBS. Perimetry analysis showed that the presence and frequency of hallucinations were related to specific types of visual field defects. The most common defects associated with CBS were central, arcuate, and paracentral scotomas, particularly those affecting both the superior and inferior visual fields. This finding is consistent with the hypothesis that CBS is related to the compensatory mechanisms of the brain in response to sensory deprivation in areas of significant visual field loss. As mentioned in a study by Lance JW, the occurrence of such hallucinations with a visual field defect suggests that the cells of the association cortex are more likely to discharge spontaneously once they are deprived of their normal afferent inflow from the calcarine cortex [ 1 ]. The nature of hallucinations varied widely among the patients, with the majority experiencing simple visual phenomena such as lines, dots, and light flickers. However, some patients reported more complex hallucinations, including faces and animals. Most of the hallucinations were monochromatic, and more than half of the patients experienced them as mobile images, which is inconsistent with previous descriptions of CBS where three patients out of four hallucinated in colour and one in black and white [ 7 ]. The episodic nature of these hallucinations and their occurrence during moments of solitude or relaxation aligns with the findings from existing studies. One study showed that hallucinations appeared more often during periods of sensory deprivation, such as inactivity or evening and nighttime [ 6 ]. This is also consistent with a previous study led by Jacob A et al. which describes various types of hallucinations [ 10 ]. The simple type includes photopsia (flashes of light), lines, or patterns (like fortification spectra, zigzags, or circles). Complex visual hallucinations, however, are usually well formed and relatively stereotyped and often involve animals and figures in bright colours and dramatic settings. Our study also highlighted the significant psychosocial impact of CBS on patients, with a majority reporting feelings of anxiety and worry due to their hallucinations. This underscores the importance of recognizing and addressing CBS in clinical practice, as it can significantly affect the quality of life of the patients. Despite the non-threatening nature of the hallucinations, only a minority of patients had sought medical advice, possibly due to a lack of awareness or the stigma associated with discussing hallucinations. Scott IU et al. showed that patients with relatively good vision who experienced hallucinations faced greater emotional distress and a reduced quality of life compared to those without hallucinations [ 9 ]. While our study includes multiple variables and an adequate sample size, further longitudinal studies are required to track the progression of CBS in patients with glaucoma. Further understanding of the pathophysiology of the disorder can give rise to effective interventions and better prognostic indicators. CONCLUSION This study contributes to the growing body of evidence on CBS in glaucoma patients, emphasizing the need for heightened awareness among healthcare providers. It also demonstrates the occurrence of CBS even in patients with good visual acuity challenging the assumption that CBS predominantly occurs in patients with severe visual acuity loss. Early identification and appropriate management of CBS can help alleviate the psychological burden on patients and improve their overall well-being. Emphasizing the variability in the type of hallucinations and the psychological impact, the management should be customised for each patient such that holistic care goes beyond treating the physical aspects of glaucoma. Educating patients about CBS could encourage them to seek help, while educational efforts for clinicians could lead to better support and reassurance for affected patients. A re-evaluation of clinical guidelines for managing glaucoma may be considered for routine screening for CBS in patients with visual impairment. By integrating CBS screening into standard ophthalmological assessments, healthcare providers can better address this condition as part of comprehensive glaucoma care. CLINICAL SIGNIFICANCE Despite its potential impact on the patient’s quality of life, CBS remains underdiagnosed and is often misinterpreted as a psychiatric illness. It can occur even among those with relatively good visual acuity and can significantly affect the emotional well-being and quality of life of patients. Timely detection and patient counselling may help to minimize the negative consequences of this condition. Abbreviations CBS – Chales Bonnet Syndrome POAG – Primary opne angle glaucoma PACG – Primary angle closure glaucoma Declarations Funding: This research received no external funding. Conflicts of Interest : The authors declare no conflict of interest. Author Contribution • Conceptualization: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Purvi Bhagat, Jignesh Gosai• Methodology: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai• Investigation: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai• Data Analysis and Interpretation: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai• Writing – Original Draft: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai• Writing – Review and Editing: Ahan Banker, Divya Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai• Supervision: Purvi Bhagat, Jignesh Gosai References Lance JW. Simple formed hallucinations confined to the area of a specific visual field defect. Brain 1976; 99:719. Burke W. The neural basis of Charles Bonnet hallucinations: a hypothesis. J Neurol Neurosurg Psychiatry 2002; 73:535. Berrios GE, Brook P. The Charles Bonnet syndrome and the problem of visual perceptual disorders in the elderly. Age Ageing 1982; 11:17. Teunisse RJ, Cruysberg JR, Hoefnagels WH, Verbeek AL, Zitman FG. Visual hallucinations in psychologically normal people: Charles Bonnet's syndrome. Lancet. 1996;347(9004):794–7. Rojas LC, Gurnani B. Charles Bonnet Syndrome. [Updated 2023 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK585133/# Peters D, Molander S, Lomo T, Singh A. Visual hallucinations in psychologically normal people: Charles Bonnet's syndrome. Ophthalmol Glaucoma. 2022 May-Jun;5(3):337–344.. Madill SA, Ffytche DH. Charles Bonnet syndrome in patients with glaucoma and good acuity. Br J Ophthalmol. 2005;89(6):785–6; author reply 786. doi: 10.1136/bjo.2005.066027/10.1136/bjo.2005.068510 . Subhi Y, Schmidt DC, Bach-Holm D, Kolko M, Singh A. Prevalence of Charles Bonnet syndrome in patients with glaucoma: a systematic review with meta-analyses. Acta Ophthalmol. 2021;99(2):128–133. Scott IU, Schein OD, Feuer WJ, Folstein MF. Visual hallucinations in patients with retinal disease. Am J Ophthalmol 2001; 131:590. Jacob A, Prasad S, Boggild M, Chandratre S. Charles Bonnet syndrome—elderly people and visual hallucinations. BMJ 2004; 328:1552. Menon GJ, Rahman I, Menon SJ, Dutton GN. Complex visual hallucinations in the visually impaired: the Charles Bonnet Syndrome. Surv Ophthalmol 2003; 48:58. Sonnenblick M, Nesher R, Rozenman Y, Nesher G. Charles Bonnet syndrome in temporal arteritis. J Rheumatol 1995; 22:1596. Kester EM. Charles Bonnet syndrome: case presentation and literature review. Optometry. 2009;80:360–366. Schadlu A, Schadlu R, Shepherd JB. Charles Bonnet syndrome: a review. Current Opinion in Ophthalmology. 2009;20:219–222. Cantin S, Duquette J, Dutrisac F, Ponton L, Courchesne M, de Abreu Cybis W, Montisci K, Wittich W, Wanet-Defalque MC. Charles Bonnet syndrome: development and validation of a screening and multidimensional descriptive questionnaire. Can J Ophthalmol. 2019;54(3):323–327. Jan T, Del Castillo J. Visual hallucinations: charles bonnet syndrome. West J Emerg Med. 2012;13(6):544–7. Jackson ML, Drohan B, Agrawal K, Rhee DJ. Charles Bonnet Syndrome and glaucoma. Ophthalmology. 2011;118(5):1005–1005.e2. Gordon KD. Prevalence of visual hallucinations in a national low vision client population. Can J Ophthalmol. 2016;51(1):3–6. Tan CS, Lim VS, Ho DY, Yeo E, Ng BY, Au Eong KG. Charles Bonnet syndrome in Asian patients in a tertiary ophthalmic centre. Br J Ophthalmol. 2004;88(10):1325–9. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 26 Aug, 2025 Read the published version in International Ophthalmology → Version 1 posted Editorial decision: Revision requested 12 May, 2025 Reviews received at journal 12 May, 2025 Reviews received at journal 09 May, 2025 Reviewers agreed at journal 09 May, 2025 Reviewers agreed at journal 08 May, 2025 Reviewers agreed at journal 07 May, 2025 Reviewers agreed at journal 06 May, 2025 Reviewers agreed at journal 06 May, 2025 Reviewers invited by journal 05 May, 2025 Editor assigned by journal 02 May, 2025 Submission checks completed at journal 02 May, 2025 First submitted to journal 30 Apr, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6566184","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":453688353,"identity":"599cc2c7-ca1e-4840-96ef-33f8a5bff3fe","order_by":0,"name":"Ahan Banker","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6ElEQVRIiWNgGAWjYDACCSBmbADTjA+AbB4+UrQwG4C0sJGihQ3EZiCohX9287MHjDvs8iTbe59Vfs2xk2FjYH746AY+S+4cMzdgPJNcLM1z3Oy27LZkoMPYjI1z8FlzI8FMgrGNOXGeRBrbbcltzEAtPGzS+LTI30j/BtRSnzhP/hlbseS2esJaDG7kgGw5nDhbgo2N8eO2w4S1GN7IKZNIPHM8cWZPGrM047bjPGzMBPwidyN9m8THHdWJM44fY/z4c1u1PT9788PHeL0PAglQmpkHTBJSjgwYf5CiehSMglEwCkYMAAB4v0KDrFS5YwAAAABJRU5ErkJggg==","orcid":"","institution":"B.J. 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Medical College and Civil Hospital","correspondingAuthor":false,"prefix":"","firstName":"Jignesh","middleName":"","lastName":"Gosai","suffix":""}],"badges":[],"createdAt":"2025-04-30 15:08:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6566184/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6566184/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10792-025-03729-6","type":"published","date":"2025-08-26T15:57:54+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":90344900,"identity":"e89dc2f5-6e63-4bef-86cf-2e76faff8ff6","added_by":"auto","created_at":"2025-09-01 16:07:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":676004,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6566184/v1/3c6fce8a-0a27-4dfc-9707-fc4c9b5ebdf8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Prevalence and Clinical Characteristics of Charles Bonnet Syndrome in Patients with Glaucoma","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eCharles Bonnet syndrome (CBS) is a condition characterised by visual hallucinations in patients who have acquired vision loss affecting the eye or visual tracts in the optic nerve, chiasm, or brain. Often referred to as release hallucinations, these visual phenomena can vary from basic, unstructured forms like lines, flashes of light, or geometric patterns to intricate, detailed images depicting people, animals, or entire scenes[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe most widely recognized explanation suggests that these hallucinations arise when the loss of visual sensory input leads to disinhibition in the visual cortex, causing it to activate spontaneously[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Originating from the visual cortex to the eyes, CBS can arise due to any condition impacting the visual pathway[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Its common aetiologies are Diabetic retinopathy, Age-related macular degeneration, Cerebral infarction, Cataract, Glaucoma, Optic neuritis, Retinitis pigmentosa, Temporal arteritis, Central retinal artery occlusion and Retinal vein occlusion [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. CBS typically occurs in patients whose visual acuity is below 0.5 in decimal terms, equivalent to Snellen measurements[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Patients with severe glaucoma may have considerable ganglion cell loss, which can lead to physiological deafferentation and increase their chance of developing CBS [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Patients with glaucoma may experience CBS more frequently than is typically recognized. The prevalence of CBS was found to be 20 percent among patients with glaucoma attending a visual rehabilitation program [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhile hallucinations are not always functionally debilitating, they can be disturbing for patients and have a detrimental influence on their quality of life including but not limited to emotional distress and social stigma [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Based on published case reports, this condition is poorly understood by healthcare professionals and is often mistaken for psychosis or an early phase of dementia[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Patients often do not disclose visual hallucinations because they believe they are signs of a mental illness [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. There is no universally accepted treatment for CBS however in some cases, when the underlying vision impairment was treated, the hallucinations were frequently resolved [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Increased visual stimulation through rapid eye movements or increased arousal such as social interactions or activities have been known to reduce the hallucinations. [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eWe conducted this study with the aim of studying the prevalence and visual characteristics of CBS and comparing the characteristics of CBS with the severity of glaucoma.\u003c/p\u003e"},{"header":"METHODOLOGY","content":"\u003cp\u003e Following the approval of the Institutional Ethics Committee, the study was conducted over 2 months from February 2024 to April 2024. 200 patients were enrolled by convenient sampling in this cross-sectional study as per the inclusion and exclusion criteria from the Department of Ophthalmology of a tertiary care center. The patients aged 18 and above diagnosed with glaucoma, with an absence of any other visual problems apart from glaucoma, and who gave written consent to be a part of the study were included. Patients diagnosed with mental illness, suffering from cognitive impairment, or any drugs likely to impair cognitive, emotional, or psychological functions were excluded from the study.\u003c/p\u003e \u003cp\u003ePatient awareness and clinical presentation of all the former types of patients of the Ophthalmology Department, during the allotted time for research, was recorded in a pre-designed Questionnaire \u003cb\u003e(Annexure I)\u003c/b\u003e [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] which contains all the necessary details of the concerned patient including his/her demographic details along with investigations such as the best corrected visual acuity, gonioscopy, perimetry inference (in the patients in whom it was possible, considering the visual acuity) and type and severity of glaucoma. The questionnaire was validated by pilot testing on 20 patients who were not included in the analysis. The data was collected securely through Google Forms. The patients were asked the questions translated into their vernacular language by the investigators, who were fluent in that particular language, and the data was filled in by the investigators on behalf of the patient.\u003c/p\u003e \u003cp\u003eThe diagnosis of glaucoma was made based on the findings of gonioscopy, broadly categorized into open angle glaucoma and closed angle glaucoma. Visual acuity as well as visual field were obtained via objective correction and perimetry respectively.\u003c/p\u003e \u003cp\u003eThe patients were asked about the nature of their hallucinations, their duration, onset, and frequency, aggravating and relieving factors as well as their effect on their routine and mental well-being. The questions were asked in their native language (Gujarati or Hindi) and were filled in by the researcher.\u003c/p\u003e \u003cp\u003eData was entered in an Excel sheet and statistical analysis was conducted using the inbuilt functions of Excel and appropriate statistical software.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 200 patients were included as per the inclusion and exclusion criteria in the study. The findings of CBS were positive in 23 patients, signifying a prevalence of 11.5%. The male-to-female ratio was 11:12 with a majority of the patients being between 50-59 years (Table-1).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTABLE-1: AGE DISTRIBUTION OF PATIENTS SUFFERING FROM CBS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAGE GROUP (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFREQUENCY\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e30-39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e40-49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e50-59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e60-69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e70-79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u0026gt;80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eMost of these patients (11) reported that the onset of hallucinations was from the past 6 months while 5 patients were observing hallucinations for 6-12 months and 7 patients for more than a year. Fourteen patients (60.87%) attested to having a daily occurrence of hallucinations, 8 patients (34.78%) had a weekly occurrence and one patient (4.35%) reported a hallucination once a month. Two patients were illiterate, four had studied up to 10\u003csup\u003eth\u003c/sup\u003e grade and one patient had completed higher secondary education. Out of the 23 patients suffering from CBS, two patients held a graduate degree or higher.\u003c/p\u003e\n\u003cp\u003eOut of the 23 patients who experienced hallucinations, 16 patients (69.57%) were cases of primary open angle glaucoma while the remaining 7 patients (30.43%) were diagnosed to have primary angle closure glaucoma (Table-2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTABLE-2: FREQUENCY OF HALLUCINATIONS AND TYPE OF GLAUCOMA\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"604\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDIAGNOSIS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEVERY DAY\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEVERY WEEK\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEVERY MONTH\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTOTAL\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003ePrimary angle closure\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003ePrimary open angle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 123px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 132px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe binocular corrected visual acuity as measured by Snellen\u0026rsquo;s chart was found to be 6/6 in ten patients, and 6/9 in four patients. One patient each had visual acuities of 6/12, 6/18, 6/24, 6/60. Only hand movements were perceived by two patients and one patient could decipher fingers at a distance of 3 meters (Table\u0026ndash;3). Perimetry interpretations were as mentioned in table-4.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTABLE-3: VISUAL ACUITY AND FREQUENCY OF HALLUCINATIONS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" rowspan=\"2\" valign=\"top\" style=\"width: 200px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eVisual Acuity\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eIncidence\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eFrequency\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eEvery day\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eEvery week\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eEvery month\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"10\" valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eRight Eye\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003eHM, PL, PR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003eNo PL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003eCF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"10\" valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eLeft Eye\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003e6/60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003eHM, PL, PR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003eNo PL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 100px;\"\u003e\n \u003cp\u003eCF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 100px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTABLE-4: FREQUENCY OF HALLUCINATIONS WITH RESPECT TO PERIMETRY\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eFINDINGS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"604\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 109px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eScotomas\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 229px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFrequency of hallucinations (Right eye)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 266px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFrequency of hallucinations (Left eye)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 109px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEvery day\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEvery week\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEvery month\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (n=23)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEvery day\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEvery week\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEvery month\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (n=23)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eSuperotemporal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eInferotemporal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eSupero and inferotemporal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eSuperior arcuate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eInferior arcuate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eSuperior and inferior arcuate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eCentral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eSuperior and inferior arcuate and central\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003eDouble \u0026nbsp;arcuate and paracentral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003e\u0026nbsp;Normal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eFive patients reported the occurrence of hallucinations prior to their visual deterioration whereas fifteen patients were affected after the development of significant visual defects: the rest stated simultaneous occurrence of hallucinations and visual impairment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe nature of hallucinations was not limited to a few specific types. A wide range of hallucinations were reported as shown in Table-5 lasting for a few seconds (eleven patients), a few minutes (ten patients), a few hours (one patient), or perennially (one patient). Twenty-one patients (91.3%) perceived the images to be real and twenty patients (86.96%) felt that the hallucinations were clearer than their actual vision. One patient also reported incidences of seeing images of dead people. The hallucinations were primarily monochromatic i.e. black and white (78.26%) with three patients (13.04%) reporting seeing hallucinations with a few specific colours and two patients (8.69%) having polychromatic hallucinations. Thirteen (56.52%) patients experienced mobile hallucinations while the others experienced stationary ones.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTABLE-5: NATURE OF HALLUCINATIONS\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTYPE OF HALLUCINATION\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFREQUENCY\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eLines\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eDots\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eLight Flickers\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eLandscapes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eShapes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eAnimals/Insects\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eTrees\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003ePeople\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eFaces\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eTapestry\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003eOther unusual perception\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 301px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe hallucinations occurred periodically with three patients each having the episodes on waking up and when they are awake, one patient each reporting the occurrence in the afternoon, morning and evening, and while reading; the rest thirteen cases had the episodes anytime during the day. The images were rarely accompanied by other sensations such as altered taste as was reported by two patients. Only one patient experienced the images attempting to communicate (talk) while twenty-one patients reported feeling as though the images were trying to touch them.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSeventeen patients often suffered from the episodes in solitude while one patient reported seeing images exclusively when alone. Fifteen people saw the images when at home. The hallucinations were reported to occur when patients were in a calm and relaxed state, often while concentrating on a specific activity, as noted by eighteen individuals.\u003c/p\u003e\n\u003cp\u003eOften, the patients attempted some strategies with varying degrees of success to make the images disappear such as blinking their eyes (43.48%), carrying out a distracting activity \u0026nbsp;(17.39%), closing their eyes (34.78%), or washing their face (8.69%).\u003c/p\u003e\n\u003cp\u003eWhile the images did not appear threatening, as was the case in twenty patients, they did have a negative effect on the mood and quality of life. Fourteen patients (60.87%) complained of worry and anxiety on seeing the hallucinations. Eleven patients were now habituated to the hallucinations while the rest were still coping with the episodes. Eleven patients had also consulted a medical professional for these hallucinations. However, these were with lower levels of education.\u0026nbsp;\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eVisual hallucinations in individuals with acquired vision impairment affecting the eyes or visual pathways are characteristic of Charles Bonnet syndrome. Commonly mistaken as a psychiatric illness, it can have a significant psychosocial impact on patients particularly leading to anxiety and distress related to visual hallucinations. There is immense variability in the type, frequency, and emotional impact of CBS hallucinations indicating that the management of the disorder should be tailor made for each individual. Improved recognition of CBS can lead to early diagnosis and appropriate management of the disorder, hence reducing patient distress.\u003c/p\u003e \u003cp\u003eOur study aimed to investigate the prevalence and characteristics of Charles Bonnet Syndrome (CBS) among patients with glaucoma. The findings revealed a CBS prevalence of 11.5% among the 200 patients included, which aligns with the existing literature by Jan T et al. [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] and Jacob A et al. [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] on the occurrence of visual hallucinations in patients with significant visual impairment, particularly those with glaucoma.\u003c/p\u003e \u003cp\u003eOur study population had an almost equal gender distribution, with a slight female predominance (male to female ratio of 11:12). The age distribution showed that most patients experiencing CBS were between 50\u0026ndash;59 years, which is consistent with the age-related nature of visual impairment and the development of CBS. In the study by Jacob A et al., it was stated that the syndrome occurs most commonly in elderly people, probably because of the prevalence of visual impairment in this group [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Surbhi Y et al. also reported female predominance amongst a CBS prevalence of 13.5% similar to our findings of a prevalence of 11.5% with a higher female affection (12:11). [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eSurbhi Y et al. [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] found that certain factors such as higher age, female gender, reduced contrast sensitivity and not living alone, in addition to low vision, could predispose to CBS; a finding also corroborated with Jackson ML et al. [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] and Gordon KD [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Taking our findings into account, we found that CBS may not be rare in elderly patients with varying degrees of glaucoma, with or without other ocular comorbidities.\u003c/p\u003e \u003cp\u003eIn terms of the types of glaucoma, a higher prevalence of CBS was observed in patients with primary open-angle glaucoma (POAG) (69.57%) compared to primary angle-closure glaucoma (PACG) (30.43%). This is in line with prior studies such as Peters D et al. [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] where out of 337 adult patients with open \u0026ndash;angle glaucoma, 7.1% presented with CBS.. This probably indicates a greater correlation of CBS with POAG, possibly due to the more progressive visual field loss associated with this condition.\u003c/p\u003e \u003cp\u003eVisual acuity measurements revealed that CBS can occur across a range of visual acuities, though a majority of the affected patients had a visual acuity of 6/6 in either or both eyes. Our study found that patients with varying degrees of visual acuity, including those with mild visual impairment, also experienced CBS, which supports the findings of Jacob A et al. of CBS in patients with relatively good visual acuity [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. This coincides with our observation where almost 52.6% of subjects with normal visual acuity presented with CBS.\u003c/p\u003e \u003cp\u003eThis differs from the findings of Scott IU et al., who identified a link between reduced visual acuity and the occurrence of CBS [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In their research, 86 patients from the Wilmer Ophthalmologic Institute Retinal Vascular Center were assessed, showing a 15.1% prevalence of visual hallucinations. Their univariate analysis indicated that factors strongly linked to hallucinations included being female, having poor visual acuity, bilateral vision loss, emotional distress, diminished functional ability, and a lower quality of life.\u003c/p\u003e \u003cp\u003eTan CS et al. noted that in patients with relatively good visual acuity, the prevalence of CBS was between 0.4% and 2% [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Conversely, in those with poorer visual acuity, prevalence rates ranged from 11\u0026ndash;12.3%. These findings indicate that reduced visual acuity may contribute to a higher likelihood of developing CBS.\u003c/p\u003e \u003cp\u003ePerimetry analysis showed that the presence and frequency of hallucinations were related to specific types of visual field defects. The most common defects associated with CBS were central, arcuate, and paracentral scotomas, particularly those affecting both the superior and inferior visual fields. This finding is consistent with the hypothesis that CBS is related to the compensatory mechanisms of the brain in response to sensory deprivation in areas of significant visual field loss. As mentioned in a study by Lance JW, the occurrence of such hallucinations with a visual field defect suggests that the cells of the association cortex are more likely to discharge spontaneously once they are deprived of their normal afferent inflow from the calcarine cortex [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe nature of hallucinations varied widely among the patients, with the majority experiencing simple visual phenomena such as lines, dots, and light flickers. However, some patients reported more complex hallucinations, including faces and animals. Most of the hallucinations were monochromatic, and more than half of the patients experienced them as mobile images, which is inconsistent with previous descriptions of CBS where three patients out of four hallucinated in colour and one in black and white [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The episodic nature of these hallucinations and their occurrence during moments of solitude or relaxation aligns with the findings from existing studies. One study showed that hallucinations appeared more often during periods of sensory deprivation, such as inactivity or evening and nighttime [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. This is also consistent with a previous study led by Jacob A et al. which describes various types of hallucinations [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The simple type includes photopsia (flashes of light), lines, or patterns (like fortification spectra, zigzags, or circles). Complex visual hallucinations, however, are usually well formed and relatively stereotyped and often involve animals and figures in bright colours and dramatic settings.\u003c/p\u003e \u003cp\u003eOur study also highlighted the significant psychosocial impact of CBS on patients, with a majority reporting feelings of anxiety and worry due to their hallucinations. This underscores the importance of recognizing and addressing CBS in clinical practice, as it can significantly affect the quality of life of the patients. Despite the non-threatening nature of the hallucinations, only a minority of patients had sought medical advice, possibly due to a lack of awareness or the stigma associated with discussing hallucinations.\u003c/p\u003e \u003cp\u003eScott IU et al. showed that patients with relatively good vision who experienced hallucinations faced greater emotional distress and a reduced quality of life compared to those without hallucinations [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhile our study includes multiple variables and an adequate sample size, further longitudinal studies are required to track the progression of CBS in patients with glaucoma. Further understanding of the pathophysiology of the disorder can give rise to effective interventions and better prognostic indicators.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThis study contributes to the growing body of evidence on CBS in glaucoma patients, emphasizing the need for heightened awareness among healthcare providers. It also demonstrates the occurrence of CBS even in patients with good visual acuity challenging the assumption that CBS predominantly occurs in patients with severe visual acuity loss.\u003c/p\u003e \u003cp\u003eEarly identification and appropriate management of CBS can help alleviate the psychological burden on patients and improve their overall well-being. Emphasizing the variability in the type of hallucinations and the psychological impact, the management should be customised for each patient such that holistic care goes beyond treating the physical aspects of glaucoma. Educating patients about CBS could encourage them to seek help, while educational efforts for clinicians could lead to better support and reassurance for affected patients.\u003c/p\u003e \u003cp\u003e A re-evaluation of clinical guidelines for managing glaucoma may be considered for routine screening for CBS in patients with visual impairment. By integrating CBS screening into standard ophthalmological assessments, healthcare providers can better address this condition as part of comprehensive glaucoma care.\u003c/p\u003e\n\u003ch3\u003eCLINICAL SIGNIFICANCE\u003c/h3\u003e\n\u003cp\u003eDespite its potential impact on the patient\u0026rsquo;s quality of life, CBS remains underdiagnosed and is often misinterpreted as a psychiatric illness. It can occur even among those with relatively good visual acuity and can significantly affect the emotional well-being and quality of life of patients. Timely detection and patient counselling \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003emay help to minimize the negative consequences of this condition.\u003c/span\u003e\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cul\u003e\n \u003cli\u003eCBS \u0026ndash; Chales Bonnet Syndrome\u003c/li\u003e\n \u003cli\u003ePOAG \u0026ndash; Primary opne angle glaucoma\u003c/li\u003e\n \u003cli\u003ePACG \u0026ndash; Primary angle closure glaucoma\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThis research received no external funding.\u003c/p\u003e \u003cp\u003e \u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003eConflicts of Interest\u003c/span\u003e: The authors declare no conflict of interest.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003e\u0026bull; Conceptualization: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Purvi Bhagat, Jignesh Gosai\u0026bull; Methodology: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai\u0026bull; Investigation: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai\u0026bull; Data Analysis and Interpretation: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai\u0026bull; Writing \u0026ndash; Original Draft: Ahan Banker, Divya Patel, Mahir Patel, Henil Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai\u0026bull; Writing \u0026ndash; Review and Editing: Ahan Banker, Divya Patel, Urva Gupta, Purvi Bhagat, Jignesh Gosai\u0026bull; Supervision: Purvi Bhagat, Jignesh Gosai\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLance JW. Simple formed hallucinations confined to the area of a specific visual field defect. Brain 1976; 99:719.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBurke W. The neural basis of Charles Bonnet hallucinations: a hypothesis. J Neurol Neurosurg Psychiatry 2002; 73:535.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBerrios GE, Brook P. The Charles Bonnet syndrome and the problem of visual perceptual disorders in the elderly. Age Ageing 1982; 11:17.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTeunisse RJ, Cruysberg JR, Hoefnagels WH, Verbeek AL, Zitman FG. Visual hallucinations in psychologically normal people: Charles Bonnet's syndrome. Lancet. 1996;347(9004):794\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRojas LC, Gurnani B. Charles Bonnet Syndrome. [Updated 2023 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.ncbi.nlm.nih.gov/books/NBK585133/#\u003c/span\u003e\u003cspan address=\"https://www.ncbi.nlm.nih.gov/books/NBK585133/#\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePeters D, Molander S, Lomo T, Singh A. Visual hallucinations in psychologically normal people: Charles Bonnet's syndrome. Ophthalmol Glaucoma. 2022 May-Jun;5(3):337\u0026ndash;344..\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMadill SA, Ffytche DH. Charles Bonnet syndrome in patients with glaucoma and good acuity. Br J Ophthalmol. 2005;89(6):785\u0026ndash;6; author reply 786. doi: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1136/bjo.2005.066027/10.1136/bjo.2005.068510\u003c/span\u003e\u003cspan address=\"10.1136/bjo.2005.066027/10.1136/bjo.2005.068510\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSubhi Y, Schmidt DC, Bach-Holm D, Kolko M, Singh A. Prevalence of Charles Bonnet syndrome in patients with glaucoma: a systematic review with meta-analyses. Acta Ophthalmol. 2021;99(2):128\u0026ndash;133.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eScott IU, Schein OD, Feuer WJ, Folstein MF. Visual hallucinations in patients with retinal disease. Am J Ophthalmol 2001; 131:590.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJacob A, Prasad S, Boggild M, Chandratre S. Charles Bonnet syndrome\u0026mdash;elderly people and visual hallucinations. BMJ 2004; 328:1552.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMenon GJ, Rahman I, Menon SJ, Dutton GN. Complex visual hallucinations in the visually impaired: the Charles Bonnet Syndrome. Surv Ophthalmol 2003; 48:58.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSonnenblick M, Nesher R, Rozenman Y, Nesher G. Charles Bonnet syndrome in temporal arteritis. J Rheumatol 1995; 22:1596.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKester EM. Charles Bonnet syndrome: case presentation and literature review. Optometry. 2009;80:360\u0026ndash;366.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchadlu A, Schadlu R, Shepherd JB. Charles Bonnet syndrome: a review. Current Opinion in Ophthalmology. 2009;20:219\u0026ndash;222.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCantin S, Duquette J, Dutrisac F, Ponton L, Courchesne M, de Abreu Cybis W, Montisci K, Wittich W, Wanet-Defalque MC. Charles Bonnet syndrome: development and validation of a screening and multidimensional descriptive questionnaire. Can J Ophthalmol. 2019;54(3):323\u0026ndash;327.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJan T, Del Castillo J. Visual hallucinations: charles bonnet syndrome. West J Emerg Med. 2012;13(6):544\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJackson ML, Drohan B, Agrawal K, Rhee DJ. Charles Bonnet Syndrome and glaucoma. Ophthalmology. 2011;118(5):1005\u0026ndash;1005.e2.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGordon KD. Prevalence of visual hallucinations in a national low vision client population. Can J Ophthalmol. 2016;51(1):3\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTan CS, Lim VS, Ho DY, Yeo E, Ng BY, Au Eong KG. Charles Bonnet syndrome in Asian patients in a tertiary ophthalmic centre. Br J Ophthalmol. 2004;88(10):1325\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"international-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"inte","sideBox":"Learn more about [International Ophthalmology](https://www.springer.com/journal/10792)","snPcode":"10792","submissionUrl":"https://submission.nature.com/new-submission/10792/3","title":"International Ophthalmology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6566184/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6566184/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cu\u003e\u003cstrong\u003eAims and Background:\u003c/strong\u003e\u003c/u\u003eCharles Bonnet Syndrome (CBS) is characterized by visual hallucinations in individuals with acquired vision loss. Despite its potential impact on the patient’s quality of life, CBS remains underdiagnosed and is often misinterpreted as a psychiatric illness. This study aims to investigate the prevalence and clinical characteristics of CBS in patients with glaucoma, also highlighting its correlation with visual acuity and severity of glaucoma.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/u\u003e: A cross-sectional study was conducted on 200 patients diagnosed with glaucoma at a tertiary care center of western India. Patients were evaluated for CBS using a pre-designed questionnaire capturing demographic data, glaucoma profiles, and details about hallucinations. Statistical analysis was performed to ascertain the prevalence of CBS and its associations.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/u\u003e: CBS was identified in 23 patients, resulting in a prevalence of 11.5%. Most affected individuals were aged 50-59 years, with a male-to-female ratio of 11:12. Most patients experienced simple visual phenomena, such as lines and light flickers. CBS was more prevalent in primary open-angle glaucoma (69.57%) compared to primary angle-closure glaucoma (30.43%). A significant proportion of patients reported that their hallucinations affected their emotional well-being and quality of life.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/u\u003e: This study underscores the prevalence of CBS in glaucoma patients, even among those with relatively good visual acuity. Recognizing CBS is crucial for appropriate management and support, as it significantly impacts the psychosocial health of patients. Increased awareness and education for both patients and clinicians are essential to ensure improved patient outcomes in overall glaucoma care.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e\u003cstrong\u003eClinical significance: \u003c/strong\u003e\u003c/u\u003eDespite its potential impact on the patient’s quality of life, CBS remains underdiagnosed and is often misinterpreted as a psychiatric illness. It can occur even among those with relatively good visual acuity and can significantly affect the emotional well-being and quality of life of patients. Timely detection and patient counselling may help to minimize the negative consequences of this condition.\u003c/p\u003e","manuscriptTitle":"Prevalence and Clinical Characteristics of Charles Bonnet Syndrome in Patients with Glaucoma","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-10 10:32:36","doi":"10.21203/rs.3.rs-6566184/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-05-12T19:13:55+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-12T05:42:02+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-09T06:57:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"40210233284426318734661186915984006894","date":"2025-05-09T06:43:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"89468345434579923269955633148328521823","date":"2025-05-08T08:59:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"28972958782946011128583892897793145758","date":"2025-05-08T01:54:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"75979394637443056427318134034510793882","date":"2025-05-06T10:26:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"237752167750022941808041046589971321904","date":"2025-05-06T07:43:41+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-05-05T20:14:20+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-05-02T09:51:37+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-02T09:44:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Ophthalmology","date":"2025-04-30T14:58:53+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"international-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"inte","sideBox":"Learn more about [International Ophthalmology](https://www.springer.com/journal/10792)","snPcode":"10792","submissionUrl":"https://submission.nature.com/new-submission/10792/3","title":"International Ophthalmology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"119e1f01-c74f-490a-a69b-05cd82045c18","owner":[],"postedDate":"May 10th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-09-01T16:02:18+00:00","versionOfRecord":{"articleIdentity":"rs-6566184","link":"https://doi.org/10.1007/s10792-025-03729-6","journal":{"identity":"international-ophthalmology","isVorOnly":false,"title":"International Ophthalmology"},"publishedOn":"2025-08-26 15:57:54","publishedOnDateReadable":"August 26th, 2025"},"versionCreatedAt":"2025-05-10 10:32:36","video":"","vorDoi":"10.1007/s10792-025-03729-6","vorDoiUrl":"https://doi.org/10.1007/s10792-025-03729-6","workflowStages":[]},"version":"v1","identity":"rs-6566184","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6566184","identity":"rs-6566184","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}