Photobiomodulation in the Treatment of Dry Age-Related Macular Degeneration: Effectiveness, Advantages, and Disadvantages

Photobiomodulation in the Treatment of Dry Age-Related Macular Degeneration: Effectiveness, Advantages, and Disadvantages | 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 Photobiomodulation in the Treatment of Dry Age-Related Macular Degeneration: Effectiveness, Advantages, and Disadvantages Ekrem Kurnaz, Savaş Özay This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7870411/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Aim To evaluate the effectiveness and reliability of photobiomodulation (PBM) in the treatment of dry age-related macular degeneration (AMD). Material and Method: The records of the 57 eyes of 34 cases consisting of 19 (55.9%) females and 15 (44.1%) males who had undergone PBM for dry AMD at the İstanbul Pendik Sistemgöz Medical center were retrospectively evaluated. Results The number of eyes with records at the 1st, 3rd and 6th month respectively was 57, 57, and 55. The best-corrected visual acuity (BCVA) before PBM was 0.360 ± 0.031 and was found to be significantly higher than baseline in the 1st month with 0.481 ± 0.039, 3rd month with 0.470 ± 0.038, and the 6th month with 0.419 ± 0.036 (p < 0.001). The rate of vision increase following PBM was 59.6% in the 1st month, 61.4% in the 3rd month, and 43.9% in the 6th month. There was no significant difference in the central retinal thickness (CRT) or central retinal volume (CRV) values at any period of the follow-up duration. The only complication following PBM was conversion to wet AMD in the first month in one case. The long session duration, the need for regular application, and the relatively high cost were found to be the main disadvantages. Conclusion PBM is an effective and reliable method in the treatment of dry AMD. However, it also has significant disadvantages. AMD PBM Figures Figure 1 Figure 2 INTRODUCTION Age-related macula degeneration (AMD) was first defined by Otto Haab in 1885 as a progressive clinical condition with macular pigmentary and atrophic changes and decreased central visual acuity ( 1 ). AMD is now characterized as a macular neurodegenerative disease ( 2 ). It is the most common cause of central vision loss in those 65 and over in developed countries. The incidence is 10% in those aged 65–75 and 25% in the over 75 group, constituting an important public health problem ( 3 , 4 ). AMD has two main forms: exudative (wet) and non-exudative (dry) ( 5 ). The exudative form constitutes 10–15% of all AMD patients but is responsible for 88% of severe AMD-related visual loss. Dry AMD is seen in 85–90% of AMD cases but is responsible for only 10–12% of severe visual loss ( 6 – 8 ). The slowly progressive dry AMD is characterized by the accumulation of extracellular material under the retinal pigment epithelium (RPE). Geographical atrophy (GA) is due to atrophy of the RPE cellular layer and results in visual loss caused by the death of macular photoreceptors ( 9 ). Wet AMD can be treated with repeated intravitreal injections of anti-vascular endothelial growth factor compounds. However, there is no approved treatment for the more commonly encountered dry AMD other than lifestyle changes and the use of vitamin supplements. This indicates a significant unmet clinical need as regards alternative treatment planning for a widening population base ( 10 , 11 ). Photobiomodulation (PBM), also known as Low Level Light Therapy (LLLT), has recently attracted attention as a potential treatment for dry AMD ( 1 ). PBM consists of a series of short applications from a light emitting diode (LED) using Near Infrared Spectrum Light (500–1000 nm). Light in this range penetrates the tissue with its wavelength and creates beneficial effects by stimulating cellular function through the activation of photoreceptors ( 12 – 17 ). LumiThera has developed the Valeda Light Transmission System PBM device that provides three wavelengths as yellow (590 nm), red (660 nm), and near infrared (NIR) (850 nm). The clinical and anatomical results have been evaluated, together with the effectiveness and reliability of the technique, in dry AMD patients who had undergone PBM treatment with the Valeda Light Transmission System at our clinic in this study. An attempt was also made to determine the reasons for not benefiting from the treatment in patients who could not or would not continue the treatment or accept maintenance treatment. MATERIAL AND METHOD This retrospective study was conducted between December 2021 and March 2025 at the Sistemgöz Medical Center by reviewing the charts of patients that had undergone PBM treatment for dry AMD. All patients were provided detailed information on the type, duration, and complications of treatment beforehand and consent forms were obtained. This study was conducted with the permission of the Bezmialem Foundation University Ethics Committees Unit Scientific Studies Ethics Committee and according to the principles stated in the Helsinki Declaration. AMD is classified into several stages according to the findings. The Age-related Eye Disease Study (AREDS) of the American Academy of Ophthalmology evaluates AMD in four stages ( 6 ). Stage 1: No drusen, bilateral non-extensive small drusen, Stage 2: (Early Stage AMD): Extensive small drusen in at least one eye, moderate drusen less than 20 in number, and pigment abnormalities, Stage 3: (Intermediate Stage AMD): Large drusen in at least one eye, extensive moderate drusen, non-central geographical atrophy, Stage 4: (Advanced Stage AMD): Geographic atrophy (GA) involving the fovea in at least one eye and choroid neovascularization (CN) or non-drusenoid retina pigment epithelium (RPE) detachment or a visual acuity (VA) under 0.63 because of early stage AMD lesions such as subfoveal drusen. The cases were first staged according to this classification. However, the aim of the study was to investigate the potential affect of PBM in various AMD stages. All cases that had undergone PBM treatment for dry AMD were therefore included without regard for AREDS classification. The study included the 57 eyes of 34 cases, consisting of 19 females and 15 males, with a best-corrected visual acuity (BCVA) of 0.05 or better. All cases were above 50 years old. The BCVA of the cases before PBM treatment was recorded. Macular evaluation was performed with OCT (OPKO/OTI Instrumentation Health, Inc. Toronto) and the central retinal thickness (CRT) and central retinal volume (CRV) were recorded. The Valeda Light Delivery System (Lumithera Valeda Light Delivery System, LumiThera Inc., Poulsbo, WA, USA) that can deliver light at three different wavelengths consisting of yellow (590 nm), red (660 nm), and near infrared (850 nm) was used in the study. The treatment took place in four phases lasting 250 seconds. In the first and third phases (35 seconds), the patient’s eyes were open and the yellow and near infrared wavelengths were delivered in pulse mode. In the second and fourth waves (90 seconds), the red wavelength was delivered continuously with the eyes closed. The PBM treatment was completed in nine sessions over 3 weeks. FBM procedures and follow-ups were performed by Ekrem Kurnaz and Savaş Özay in all cases. None of the patients encountered any unwanted effects during the treatment. Afterwards, OCT was performed and the BCVA recorded at the 1st, 3rd, and 6th months. The results were evaluated anatomically (CRT and CRV) and clinically (BCVA). The criterion of success was determined as an increase in the visual acuity of 0.1 or more. Patients who had a media opacity in the anterior segment or lens that could prevent imaging, those with a history of active wet AMD and other retinal disease (diabetic maculopathy, macular scar, pigment epithelium detachment, retinitis pigmentosa), those with a history of sensitivity to yellow light or near infrared (NIR) light, and patients with a light-triggered central nervous system disease (epilepsy, migraine, etc.) were excluded from the study. The 53 patients that refused treatment from the beginning and 20 cases that did not accept maintenance treatment after a PBM treatment cycle (9 sessions), were evaluated as to why they would not or could not accept the treatment, for a total of 73 cases. Three options were presented to the patients as the reason for refusing PBM treatment and the patients could select multiple options. However, any reasons they provided other than these 3 options were also recorded. RESULTS A total of 34 cases, consisting of 19 (55.9%) females and 15 (44.1) males were included in the study. The age range was 50–87 years and the mean age was 73.2 ± 10.4 years. Follow-up duration was 3–6 months and the mean follow-up duration was 5.8 ± 0.6 months. Only one eye was evaluated in 11 cases (32.4%) and both eyes in 23 cases (67.6%). A total of 57 eyes were evaluated, consisting of 32 (56.1) right eyes and 25 (43.9) left eyes (Table 1 ). The visual acuity (VA) increased 28.5% in the 1st month, 28.6% in the 3rd month, and 16.7% in the 6th month after PBM compared to the pre-PBM value. The VA increase success rate after PBM was 596% in the 1st month, 61.4% in the 3rd month, and 43.9% in the 6th month (Table 2 ). The VA values at 1, 3, and 6 months after PBM were statistically significantly higher than the pre-PBM value (p < 0.001). The vision values showed statistically significant changes during the follow-up periods. Although the high success rate in the 1st month gradually decreased, it was still statistically significantly higher than the baseline value at the 6th month ( Graph 1 ). The CRT values 6 months after PBM showed a decrease of 0.49% compared to the pre-PBM state. The rate of change of 20 microns or more in the CRT after PBM was found to be 7.0% (Table 3 ). The CRT values 6 months after PBM did not show any statistically significant difference when compared to the CRT values before PBM. Similarly, the CRV values 6 months after PBM showed a decrease of 0.41% compared to the pre-PBM CRV values. The rate of a 1 mm3 or higher change in the CRV following PBM was 1.8% (Table 4 ). There was no statistically significant difference between the CRV values 6 months after PBM and those before PBM (Fig. 1 ). The only complication was conversion from dry AMD to wet AMD after PBM in one case (Fig. 2 ). The reason stated by patients to refuse the treatment was statistically evaluated by providing multiple options. The most commonly chosen option was “the session duration is too long” with 43 (58.9%) cases. In second place was “has to be repeated throughout life” with 26 (35.6%) cases and the third was “the cost is too high” with 16 (21.9%) cases. The distribution of the options showed a statistically significant difference when evaluated with the single sample chi square test (Table 5 ). STATISTICAL METHOD The data were evaluated with the IBM SPSS Statistics Standard Concurrent User V 30 (IBM Corp., Armonk, New York, ABD) statistical package software. Descriptive statistics were summarized as the number of units (n), percentage (%), mean, standard deviation, standard error, median, minimum and maximum. A normal distribution of data from numerical variables was evaluated with the Shapiro-Wilk normalcy test. The variance homogeneity of the groups was evaluated with the Levene test. One eye of some patients and both eyes of others were evaluated and the vision, CRT and CRV values were therefore evaluated according to the follow-up time using linear mixed models. The Bonferroni correction was applied in dual comparisons. The single sample chi square test was used to evaluate the presence of a difference in the distribution of reasons for refusing PBM treatment. A p value < 0.05 was considered statistically significant. Table 1 Descriptive Characteristics of the Patients Variables Statistics Gender , n (%) Female 19 (55.9) Male 15 (44.1) Age (years) 73.2 ± 10.4 (50–87) Follow-up Duration (months) 5.8 ± 0.6 ( 3 – 6 ) Evaluated Eye , n (%) Single 11 (32.4) Bilateral 23 (67.6) Evaluated Side , n* (%) Right 32 (56.1) Left 25 (43.9) n : Number of patients, n * : Number of eyes, %: The percent value of the numerical variables have been presented as the mean ± standard deviation (minimum-maximum) value. Table 2 Comparison of the Vision Values Follow-up Vision statistics mean ± standard error Post-PBM vision % increase Median (min-max) Post-PBM vision success rate n (%) Test statistics † F p Pre-PBM 0.360 ± 0.031 - - 27.669 < 0.001 1st month 0.481 ± 0.039* 28.5 (0-300) 34 (59.6) 3rd month 0.470 ± 0.038* 28.6 (0-300) 35 (61.4) 6th month 0.419 ± 0.036* 16.7 (-50-100) 25 (43.9) † : Linear mixed models, n: Number of eyes, %: Percent value, *Statistically significant at the p < 0.001 level compared to the pre-PBM value. Graph 1 Changes in vision values by month (Mean ± standard error) Pre-PBM Post-PBM 1st month Post-PBM 3rd month Post-PBM 6th month Table 3 Comparison of the CRT Values of the Cases Follow-up CRT statistics mean ± standard error Post PBM CRT % decrease Median (min-max) Post-PBM CRT change of 20 microns or more n (%) Test statistics † F P Pre-PBM 203.70 ± 4.34 - - 0.032 0.859 6th month 202.61 ± 4.28 0.49 (-1.74-7.48) 4 (7.0) † : Linear mixed models Table 4 Comparison of the CRV Values of the Cases Follow-up CRV statistics mean ± standard error Post-PBM CRV % decrease Median (min-max) Post-PBM CRV change of 1 mm 3 and more n (%) Test statistics † F P Pre-PBM 7.31 ± 0.52 - - 0.033 0.856 6th month 7.29 ± 0.55 0.41 (-15.98-4,38) 1 (1.8) † : Linear mixed models Table 5 Reason for rejecting PBM treatment (N = 73)* n % p Session duration is too long 43 58.9 < 0.001 δ Needs constant repeating 26 35.6 The cost is high 16 21.9 I am old 3 4.1 State hospitals do not provide it 2 2.7 I do not believe it will be effective 2 2.7 Needs to become more widespread first 1 1.4 *: Multiple reasons could be presented by a single patient. δ : Single Sample Chi Square Test Pre-PBM CRV and CRT Post-PBM 6th month CRV and CRT DISCUSSION A semiconductor diode laser was first reported in 2008 to be used in the treatment of all AMD forms and to provide a significant improvement in the BCVA ( 18 ). Many recent clinical studies have reported that PBM treatment can be used in GA cases where the central fovea is not involved yet and in intermediate AMD cases ( 9 , 19 – 21 ). The Toronto and Oak Ridge Photobiomodulation (TORPA) study has investigated the effect of PBM in intermediate age-related dry macula degeneration with vision loss. There was statistically significant improvement in the BCVA and contrast sensitivity six weeks and one year after treatment ( 19 ). The Markowitz SN et al. study (LIGHTSITE I) is the first single-center and randomized control study to evaluate PBM effectiveness in AMD. An improvement of more than 5 letters was found in 50% of the cases. Although decreasing after 6 months, the BCVA increased again after the second session of treatment ( 20 ). The prospective double-masked randomized 8-center study by Burton et al. (LIGHTSITE II) also showed a visual improvement of 5 letters ( 21 ). A prospective, randomized, double-masked study conducted at 10 centers by Boyer et al. (LIGHTSITE III) found a visual improvement of 5.5 letters ( 9 ). The TORPA II study by Merry GF has reported the repeatability of TORPA results and found no change in the CRT despite an improvement in the BCVA at the end of the 3-week follow-up ( 22 ). The results from our study are similar to those reported in the literature. There was a VA increase of 28.5% in the 1st month, 28.6% in the 3rd month, and 16.7% in the 6th month compared to the pre-PBM state. Although the BCVA success rate obtained in the 1st month gradually decreased, it was still significantly higher than the baseline even at the end of the 6th month (p < 0.001). The results are more successful in AMD cases with higher baseline values ( 5 ). Henschel et al. are among the investigators evaluating the relationship between retinal thickness and visual acuity, and they have found a connection between retinal thickness and decreased visual acuity in their study comparing optical coherence findings and visual acuity in AMD ( 23 ). Ting et al. have conducted a similar study and found a relationship between the increasing retinal thickness in neovascular AMD and worse visual acuity in these patients ( 24 ). However, no significant change in the CRT or even CRV has been found after PBM in dry AMD cases despite the significant increase in vision ( 5 , 22 ). Similarly, no significant change was found in the CRT and CRV despite the significant increase in BCVA in this study. This is also similar to the results in the literature. The only complication was the conversion of one case from dry AMD to wet AMD. A prospective and randomized multicenter study has reported the conversion rate from dry AMD to wet AMD to be much higher in the PBM group than in the control group (5.4% vs. 1.8%) ( 9 ). However, there is no information or finding related to the triggering of conversion or transition of dry AMD to wet AMD with PBM. Longer studies with a control group and a larger number of cases are required. Other potentially variable anatomical changes such as drusen volume, drusen thickness, geographic atrophy or contrast sensitivity were not evaluated as they were not within the scope of our study. The lack of these evaluations and a control group constitute the weaknesses of our study. The strong aspect is determining the reasons for patients who do not want to undergo this treatment although they need it, a subject not mentioned in the literature. The main disadvantages are that a full cycle is too long (a total of 9 sessions, with sessions every other day, taking approximately 20 days), it has to be repeated twice a year throughout life, and is relatively expensive. These disadvantages cause approximately one in two cases to reject treatment or drop out after starting. This means that the development of new PBM devices with fewer sessions and longer effective duration is needed. In conclusion, PBM treatment is an effective and safe method in dry AMD cases. Clinically, a vision increase that is satisfactory for the patients can be achieved. In addition, the main advantages are that it is noninvasive, can be easily administered, can be repeated, lacks complications, has no alternative, and can be used safely and easily at any clinic by any physician. The important disadvantages are the long session duration, the need for continuous repetition, and relatively high cost. Declarations Authors Ekrem Kurnaz, Savaş Özay Author Contribution E.K. wrote the main manuscript.All authors reviewed the manuscript. References Haab, O. Erkrankungen der Macula Lutea. Centralblatt Augenheilkd. 1985;9:384–91. Klein R. Epidemiology of age-related macular degeneration. In: Penfold PL, Provis JM eds: Macular Degeneration. Germany, Springer-Verlag Berlin Heidelberg, 2005;5:79–101. Lotery A, Xu X, Zlatava G, Loftus J. Burden of illness, visual impairment and health resource utilisation of patients with neovascular age-related macular degeneration: results from the UK cohort of a five-country cross-sectional study. Br J Ophthalmol. 2007;91:1303–7. Liu TY, Shah AR, Del Priore LV. Progression of lesion size in untreated eyes with exudative age-related macular degeneration a meta-analysis using Lineweaver–Burk plots. JAMA Ophthalmol. 2013;131:335–40. Graham F. Et al. 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Decreased visual acuity associated with cystoid macular edema in neovascular age-related macular degeneration. Arch Ophthalmol. 2002;120(6):731–7. Graph 1 Graph 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Graph1.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 06 Dec, 2025 Reviews received at journal 28 Nov, 2025 Reviewers agreed at journal 23 Oct, 2025 Reviewers invited by journal 23 Oct, 2025 Editor assigned by journal 20 Oct, 2025 Submission checks completed at journal 20 Oct, 2025 First submitted to journal 15 Oct, 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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16:33:17","extension":"xml","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":66951,"visible":true,"origin":"","legend":"","description":"","filename":"3eb36efe0b914fe9b131869ec93ab0a71structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7870411/v1/b03038c85ea6e08cdf8e88b8.xml"},{"id":95228296,"identity":"5ad49804-910c-4386-ac5d-0a41d6efed79","added_by":"auto","created_at":"2025-11-05 16:33:35","extension":"html","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":73961,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7870411/v1/5f7c22ae55d3730fc532fc23.html"},{"id":95171372,"identity":"8741cda9-57e4-43c6-bac6-c66ee84cc6b1","added_by":"auto","created_at":"2025-11-05 06:32:19","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":743986,"visible":true,"origin":"","legend":"\u003cp\u003ePost-PBM 6th month with no significant change in the CRT or CRV (random case)\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7870411/v1/c4957459f808bc2badfe36e2.png"},{"id":95227439,"identity":"79fddeeb-be1d-4918-82e0-b136fa93d524","added_by":"auto","created_at":"2025-11-05 16:32:30","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1090181,"visible":true,"origin":"","legend":"\u003cp\u003eThe single case where wet AMD developed in the post-PBM 1st month\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7870411/v1/b8a20901443abe5e3d0e1ad6.png"},{"id":95230743,"identity":"d255cdb4-b3a0-4b6e-9e07-89b7ce8476db","added_by":"auto","created_at":"2025-11-05 16:38:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2768417,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7870411/v1/93f30c2a-172f-4de2-8eb8-d007015a1b61.pdf"},{"id":95171370,"identity":"831cabc0-40df-4385-b213-27f272f60151","added_by":"auto","created_at":"2025-11-05 06:32:19","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":17741,"visible":true,"origin":"","legend":"","description":"","filename":"Graph1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7870411/v1/3adfe81f3950176c9e67e27f.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Photobiomodulation in the Treatment of Dry Age-Related Macular Degeneration: Effectiveness, Advantages, and Disadvantages","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eAge-related macula degeneration (AMD) was first defined by Otto Haab in 1885 as a progressive clinical condition with macular pigmentary and atrophic changes and decreased central visual acuity (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). AMD is now characterized as a macular neurodegenerative disease (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). It is the most common cause of central vision loss in those 65 and over in developed countries. The incidence is 10% in those aged 65\u0026ndash;75 and 25% in the over 75 group, constituting an important public health problem (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAMD has two main forms: exudative (wet) and non-exudative (dry) (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). The exudative form constitutes 10\u0026ndash;15% of all AMD patients but is responsible for 88% of severe AMD-related visual loss. Dry AMD is seen in 85\u0026ndash;90% of AMD cases but is responsible for only 10\u0026ndash;12% of severe visual loss (\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). The slowly progressive dry AMD is characterized by the accumulation of extracellular material under the retinal pigment epithelium (RPE). Geographical atrophy (GA) is due to atrophy of the RPE cellular layer and results in visual loss caused by the death of macular photoreceptors (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eWet AMD can be treated with repeated intravitreal injections of anti-vascular endothelial growth factor compounds. However, there is no approved treatment for the more commonly encountered dry AMD other than lifestyle changes and the use of vitamin supplements. This indicates a significant unmet clinical need as regards alternative treatment planning for a widening population base (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e).\u003c/p\u003e\u003cp\u003ePhotobiomodulation (PBM), also known as Low Level Light Therapy (LLLT), has recently attracted attention as a potential treatment for dry AMD (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). PBM consists of a series of short applications from a light emitting diode (LED) using Near Infrared Spectrum Light (500\u0026ndash;1000 nm). Light in this range penetrates the tissue with its wavelength and creates beneficial effects by stimulating cellular function through the activation of photoreceptors (\u003cspan additionalcitationids=\"CR13 CR14 CR15 CR16\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). LumiThera has developed the Valeda Light Transmission System PBM device that provides three wavelengths as yellow (590 nm), red (660 nm), and near infrared (NIR) (850 nm).\u003c/p\u003e\u003cp\u003eThe clinical and anatomical results have been evaluated, together with the effectiveness and reliability of the technique, in dry AMD patients who had undergone PBM treatment with the Valeda Light Transmission System at our clinic in this study. An attempt was also made to determine the reasons for not benefiting from the treatment in patients who could not or would not continue the treatment or accept maintenance treatment.\u003c/p\u003e"},{"header":"MATERIAL AND METHOD","content":"\u003cp\u003e This retrospective study was conducted between December 2021 and March 2025 at the Sistemg\u0026ouml;z Medical Center by reviewing the charts of patients that had undergone PBM treatment for dry AMD. All patients were provided detailed information on the type, duration, and complications of treatment beforehand and consent forms were obtained. This study was conducted with the permission of the Bezmialem Foundation University Ethics Committees Unit Scientific Studies Ethics Committee and according to the principles stated in the Helsinki Declaration.\u003c/p\u003e\u003cp\u003eAMD is classified into several stages according to the findings. The Age-related Eye Disease Study (AREDS) of the American Academy of Ophthalmology evaluates AMD in four stages (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eStage 1: No drusen, bilateral non-extensive small drusen,\u003c/p\u003e\u003cp\u003eStage 2: (Early Stage AMD): Extensive small drusen in at least one eye, moderate drusen less than 20 in number, and pigment abnormalities,\u003c/p\u003e\u003cp\u003eStage 3: (Intermediate Stage AMD): Large drusen in at least one eye, extensive moderate drusen, non-central geographical atrophy,\u003c/p\u003e\u003cp\u003eStage 4: (Advanced Stage AMD): Geographic atrophy (GA) involving the fovea in at least one eye and choroid neovascularization (CN) or non-drusenoid retina pigment epithelium (RPE) detachment or a visual acuity (VA) under 0.63 because of early stage AMD lesions such as subfoveal drusen.\u003c/p\u003e\u003cp\u003eThe cases were first staged according to this classification. However, the aim of the study was to investigate the potential affect of PBM in various AMD stages. All cases that had undergone PBM treatment for dry AMD were therefore included without regard for AREDS classification. The study included the 57 eyes of 34 cases, consisting of 19 females and 15 males, with a best-corrected visual acuity (BCVA) of 0.05 or better. All cases were above 50 years old.\u003c/p\u003e\u003cp\u003eThe BCVA of the cases before PBM treatment was recorded. Macular evaluation was performed with OCT (OPKO/OTI Instrumentation Health, Inc. Toronto) and the central retinal thickness (CRT) and central retinal volume (CRV) were recorded.\u003c/p\u003e\u003cp\u003eThe Valeda Light Delivery System (Lumithera Valeda Light Delivery System, LumiThera Inc., Poulsbo, WA, USA) that can deliver light at three different wavelengths consisting of yellow (590 nm), red (660 nm), and near infrared (850 nm) was used in the study. The treatment took place in four phases lasting 250 seconds. In the first and third phases (35 seconds), the patient\u0026rsquo;s eyes were open and the yellow and near infrared wavelengths were delivered in pulse mode. In the second and fourth waves (90 seconds), the red wavelength was delivered continuously with the eyes closed. The PBM treatment was completed in nine sessions over 3 weeks. FBM procedures and follow-ups were performed by Ekrem Kurnaz and Savaş \u0026Ouml;zay in all cases. None of the patients encountered any unwanted effects during the treatment. Afterwards, OCT was performed and the BCVA recorded at the 1st, 3rd, and 6th months. The results were evaluated anatomically (CRT and CRV) and clinically (BCVA). The criterion of success was determined as an increase in the visual acuity of 0.1 or more.\u003c/p\u003e\u003cp\u003ePatients who had a media opacity in the anterior segment or lens that could prevent imaging, those with a history of active wet AMD and other retinal disease (diabetic maculopathy, macular scar, pigment epithelium detachment, retinitis pigmentosa), those with a history of sensitivity to yellow light or near infrared (NIR) light, and patients with a light-triggered central nervous system disease (epilepsy, migraine, etc.) were excluded from the study.\u003c/p\u003e\u003cp\u003eThe 53 patients that refused treatment from the beginning and 20 cases that did not accept maintenance treatment after a PBM treatment cycle (9 sessions), were evaluated as to why they would not or could not accept the treatment, for a total of 73 cases. Three options were presented to the patients as the reason for refusing PBM treatment and the patients could select multiple options. However, any reasons they provided other than these 3 options were also recorded.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 34 cases, consisting of 19 (55.9%) females and 15 (44.1) males were included in the study. The age range was 50\u0026ndash;87 years and the mean age was 73.2\u0026thinsp;\u0026plusmn;\u0026thinsp;10.4 years. Follow-up duration was 3\u0026ndash;6 months and the mean follow-up duration was 5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6 months. Only one eye was evaluated in 11 cases (32.4%) and both eyes in 23 cases (67.6%). A total of 57 eyes were evaluated, consisting of 32 (56.1) right eyes and 25 (43.9) left eyes (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe visual acuity (VA) increased 28.5% in the 1st month, 28.6% in the 3rd month, and 16.7% in the 6th month after PBM compared to the pre-PBM value. The VA increase success rate after PBM was 596% in the 1st month, 61.4% in the 3rd month, and 43.9% in the 6th month (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The VA values at 1, 3, and 6 months after PBM were statistically significantly higher than the pre-PBM value (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The vision values showed statistically significant changes during the follow-up periods. Although the high success rate in the 1st month gradually decreased, it was still statistically significantly higher than the baseline value at the 6th month (\u003cb\u003eGraph 1\u003c/b\u003e).\u003c/p\u003e\u003cp\u003eThe CRT values 6 months after PBM showed a decrease of 0.49% compared to the pre-PBM state. The rate of change of 20 microns or more in the CRT after PBM was found to be 7.0% (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The CRT values 6 months after PBM did not show any statistically significant difference when compared to the CRT values before PBM. Similarly, the CRV values 6 months after PBM showed a decrease of 0.41% compared to the pre-PBM CRV values. The rate of a 1 mm3 or higher change in the CRV following PBM was 1.8% (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). There was no statistically significant difference between the CRV values 6 months after PBM and those before PBM (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe only complication was conversion from dry AMD to wet AMD after PBM in one case (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e).\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe reason stated by patients to refuse the treatment was statistically evaluated by providing multiple options. The most commonly chosen option was \u0026ldquo;the session duration is too long\u0026rdquo; with 43 (58.9%) cases. In second place was \u0026ldquo;has to be repeated throughout life\u0026rdquo; with 26 (35.6%) cases and the third was \u0026ldquo;the cost is too high\u0026rdquo; with 16 (21.9%) cases. The distribution of the options showed a statistically significant difference when evaluated with the single sample chi square test (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003eSTATISTICAL METHOD\u003c/h3\u003e\n\u003cp\u003eThe data were evaluated with the IBM SPSS Statistics Standard Concurrent User V 30 (IBM Corp., Armonk, New York, ABD) statistical package software. Descriptive statistics were summarized as the number of units (n), percentage (%), mean, standard deviation, standard error, median, minimum and maximum. A normal distribution of data from numerical variables was evaluated with the Shapiro-Wilk normalcy test. The variance homogeneity of the groups was evaluated with the Levene test. One eye of some patients and both eyes of others were evaluated and the vision, CRT and CRV values were therefore evaluated according to the follow-up time using linear mixed models. The Bonferroni correction was applied in dual comparisons. The single sample chi square test was used to evaluate the presence of a difference in the distribution of reasons for refusing PBM treatment. A p value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDescriptive Characteristics of the Patients\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariables\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eStatistics\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eGender\u003c/b\u003e, \u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e19 (55.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e15 (44.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAge\u003c/b\u003e (years)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e73.2\u0026thinsp;\u0026plusmn;\u0026thinsp;10.4 (50\u0026ndash;87)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eFollow-up Duration\u003c/b\u003e (months)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6 (\u003cspan additionalcitationids=\"CR4 CR5\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eEvaluated Eye\u003c/b\u003e, \u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSingle\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11 (32.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBilateral\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e23 (67.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eEvaluated Side\u003c/b\u003e, \u003cem\u003en*\u003c/em\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRight\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e32 (56.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLeft\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e25 (43.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003en\u003c/em\u003e: Number of patients, \u003cem\u003en\u003c/em\u003e\u003csup\u003e*\u003c/sup\u003e: Number of eyes, %: The percent value of the numerical variables have been presented as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (minimum-maximum) value.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of the Vision Values\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eFollow-up\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eVision statistics\u003c/p\u003e\u003cp\u003emean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard error\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost-PBM vision % increase\u003c/p\u003e\u003cp\u003eMedian (min-max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost-PBM vision success rate\u003c/p\u003e\u003cp\u003e\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003eTest statistics\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePre-PBM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.360\u0026thinsp;\u0026plusmn;\u0026thinsp;0.031\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e27.669\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e1st month\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.481\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039*\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e28.5 (0-300)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e34 (59.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e3rd month\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.470\u0026thinsp;\u0026plusmn;\u0026thinsp;0.038*\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e28.6 (0-300)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e35 (61.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6th month\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.419\u0026thinsp;\u0026plusmn;\u0026thinsp;0.036*\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16.7 (-50-100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e25 (43.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e: Linear mixed models, n: Number of eyes, %: Percent value, *Statistically significant at the p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 level compared to the pre-PBM value.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eGraph 1\u003c/strong\u003e\u003cp\u003eChanges in vision values by month (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard error)\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003ePre-PBM Post-PBM 1st month Post-PBM 3rd month Post-PBM 6th month\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of the CRT Values of the Cases\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eFollow-up\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eCRT statistics\u003c/p\u003e\u003cp\u003emean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard error\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost PBM CRT % decrease\u003c/p\u003e\u003cp\u003eMedian (min-max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost-PBM CRT change of 20 microns or more\u003c/p\u003e\u003cp\u003e\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003eTest statistics\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePre-PBM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e203.70\u0026thinsp;\u0026plusmn;\u0026thinsp;4.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.032\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.859\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6th month\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e202.61\u0026thinsp;\u0026plusmn;\u0026thinsp;4.28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.49 (-1.74-7.48)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 (7.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e: Linear mixed models\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of the CRV Values of the Cases\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eFollow-up\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eCRV statistics\u003c/p\u003e\u003cp\u003emean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard error\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost-PBM CRV % decrease\u003c/p\u003e\u003cp\u003eMedian (min-max)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost-PBM CRV change of 1 mm\u003csup\u003e3\u003c/sup\u003e and more\u003c/p\u003e\u003cp\u003e\u003cem\u003en\u003c/em\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003eTest statistics\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePre-PBM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.033\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.856\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6th month\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7.29\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.41 (-15.98-4,38)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1 (1.8)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e: Linear mixed models\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eReason for rejecting PBM treatment (N\u0026thinsp;=\u0026thinsp;73)*\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003en\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e%\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSession duration is too long\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e58.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"6\" rowspan=\"7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003csup\u003eδ\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNeeds constant repeating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e35.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eThe cost is high\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e21.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI am old\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eState hospitals do not provide it\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI do not believe it will be effective\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNeeds to become more widespread first\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e*: Multiple reasons could be presented by a single patient. \u003csup\u003eδ\u003c/sup\u003e: Single Sample Chi Square Test\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003ePre-PBM CRV and CRT Post-PBM 6th month CRV and CRT\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eA semiconductor diode laser was first reported in 2008 to be used in the treatment of all AMD forms and to provide a significant improvement in the BCVA (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eMany recent clinical studies have reported that PBM treatment can be used in GA cases where the central fovea is not involved yet and in intermediate AMD cases (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan additionalcitationids=\"CR20\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe Toronto and Oak Ridge Photobiomodulation (TORPA) study has investigated the effect of PBM in intermediate age-related dry macula degeneration with vision loss. There was statistically significant improvement in the BCVA and contrast sensitivity six weeks and one year after treatment (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe Markowitz SN et al. study (LIGHTSITE I) is the first single-center and randomized control study to evaluate PBM effectiveness in AMD. An improvement of more than 5 letters was found in 50% of the cases. Although decreasing after 6 months, the BCVA increased again after the second session of treatment (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe prospective double-masked randomized 8-center study by Burton et al. (LIGHTSITE II) also showed a visual improvement of 5 letters (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eA prospective, randomized, double-masked study conducted at 10 centers by Boyer et al. (LIGHTSITE III) found a visual improvement of 5.5 letters (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe TORPA II study by Merry GF has reported the repeatability of TORPA results and found no change in the CRT despite an improvement in the BCVA at the end of the 3-week follow-up (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe results from our study are similar to those reported in the literature. There was a VA increase of 28.5% in the 1st month, 28.6% in the 3rd month, and 16.7% in the 6th month compared to the pre-PBM state. Although the BCVA success rate obtained in the 1st month gradually decreased, it was still significantly higher than the baseline even at the end of the 6th month (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The results are more successful in AMD cases with higher baseline values (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eHenschel et al. are among the investigators evaluating the relationship between retinal thickness and visual acuity, and they have found a connection between retinal thickness and decreased visual acuity in their study comparing optical coherence findings and visual acuity in AMD (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e). Ting et al. have conducted a similar study and found a relationship between the increasing retinal thickness in neovascular AMD and worse visual acuity in these patients (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). However, no significant change in the CRT or even CRV has been found after PBM in dry AMD cases despite the significant increase in vision (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). Similarly, no significant change was found in the CRT and CRV despite the significant increase in BCVA in this study. This is also similar to the results in the literature.\u003c/p\u003e\u003cp\u003eThe only complication was the conversion of one case from dry AMD to wet AMD. A prospective and randomized multicenter study has reported the conversion rate from dry AMD to wet AMD to be much higher in the PBM group than in the control group (5.4% vs. 1.8%) (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). However, there is no information or finding related to the triggering of conversion or transition of dry AMD to wet AMD with PBM. Longer studies with a control group and a larger number of cases are required.\u003c/p\u003e\u003cp\u003eOther potentially variable anatomical changes such as drusen volume, drusen thickness, geographic atrophy or contrast sensitivity were not evaluated as they were not within the scope of our study. The lack of these evaluations and a control group constitute the weaknesses of our study. The strong aspect is determining the reasons for patients who do not want to undergo this treatment although they need it, a subject not mentioned in the literature.\u003c/p\u003e\u003cp\u003eThe main disadvantages are that a full cycle is too long (a total of 9 sessions, with sessions every other day, taking approximately 20 days), it has to be repeated twice a year throughout life, and is relatively expensive. These disadvantages cause approximately one in two cases to reject treatment or drop out after starting. This means that the development of new PBM devices with fewer sessions and longer effective duration is needed.\u003c/p\u003e\u003cp\u003eIn conclusion, PBM treatment is an effective and safe method in dry AMD cases. Clinically, a vision increase that is satisfactory for the patients can be achieved. In addition, the main advantages are that it is noninvasive, can be easily administered, can be repeated, lacks complications, has no alternative, and can be used safely and easily at any clinic by any physician. The important disadvantages are the long session duration, the need for continuous repetition, and relatively high cost.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eAuthors\u003c/h2\u003e\u003cp\u003eEkrem Kurnaz, Savaş \u0026Ouml;zay\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eE.K. wrote the main manuscript.All authors reviewed the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHaab, O. Erkrankungen der Macula Lutea. Centralblatt Augenheilkd. 1985;9:384\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKlein R. Epidemiology of age-related macular degeneration. In: Penfold PL, Provis JM eds: Macular Degeneration. Germany, Springer-Verlag Berlin Heidelberg, 2005;5:79\u0026ndash;101.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLotery A, Xu X, Zlatava G, Loftus J. Burden of illness, visual impairment and health resource utilisation of patients with neovascular age-related macular degeneration: results from the UK cohort of a five-country cross-sectional study. Br J Ophthalmol. 2007;91:1303\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLiu TY, Shah AR, Del Priore LV. Progression of lesion size in untreated eyes with exudative age-related macular degeneration a meta-analysis using Lineweaver\u0026ndash;Burk plots. JAMA Ophthalmol. 2013;131:335\u0026ndash;40.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGraham F. Et al. Photobiomodulation reduces drusen volume and improves visual acuity and contrast sensitivity in dry age-related macular degeneration Acta Ophthalmol. 2017: 95: e270\u0026ndash;e277\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAge-Related Eye Disease Study Research Group: Risk factors associated with age-related macular degeneration. A case-control study in the age-related eye disease study: Age-Related Eye Disease Study Report Number 3. Ophthalmology. 2000;107:2224\u0026ndash;32.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKlein R, Meuer SM, Myers CE, et al. Harmonizing the Classification of Age-related Macular Degeneration in the Three-Continent AMD Consortium; Ophthalmic Epidemiology. 2014;21:14\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eThe Age-Related Eye Disease Study system for classifying age-related macular degeneration from stereoscopic color fundus photographs: the Age-Related Eye Disease Study Report Number 6. Am J Ophthalmol. 2001;132:668\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBoyer et al. PBM Improves Clinical Outcomes in AMD. Retina, The Journal and Vitreus Diseases. 2024;44:487\u0026ndash;97.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChew EY, Chew EY, Clemons TE, et al. Secondary analyses of the effects of lutein/zeaxanthin on age-related macular degeneration progression: AREDS2 report No. 3. JAMA Ophthalmol 2014;132:142\u0026ndash;149.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAronow ME, Chew EY. Age-Related Eye Disease Study 2: perspectives, recommendations, and unanswered questions. Curr Opin Ophthalmol 2014;25:186\u0026ndash;190.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRojas JC, Lee J, John JM \u0026amp; Gonzalez-Lima F. Neuroprotective effects of near-infrared light in an in vivo model of mitochondrial optic neuropathy. J Neurosci. 2008;28:13511\u0026ndash;13521.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTata DB, Waynant RW. Laser therapy: a review of its mechanism of action and potential medical applications. Laser Photonics Rev 2010;5: 1\u0026ndash;12.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRojas JC, Gonzalaz-Lima F. Low level light therapy of the eye and brain. Dovepress. 2011;2011: 49\u0026ndash;67.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSzymanska J, Goralczyk K, Klawe JJ, et al. Phototherapy with low-level laser influences the proliferation of endothelial cells and vascular endothelial growth factor and transforming growth factor-beta secretion. \u003cem\u003eJ Physiol Pharmacol.\u003c/em\u003e 2013;64(3):387\u0026ndash;391.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWong-Riley MT, Liang HL, Eells JT, et al. Photobiomodulation directly benefits primary neurons functionally inactivated by toxins: role of cytochrome c oxidase. \u003cem\u003eJ Biol Chem.\u003c/em\u003e 2005;280(6):4761\u0026ndash;4771.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKaru T. Mitochondrial mechanisms of photobiomodulation in context of new data about multiple roles of ATP. Photomed Laser Surg. 2010;28(2):159\u0026ndash;160.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eIvandic BT, Ivandic T. Low-level laser therapy improves vision in patients with age-related macular degeneration. Photomed Laser Surg. 2008;26(3):241\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMerry G, Dotson R, Devenyi R, Markowitz S, Reyes S. Photobiomodulation as a new treatment for dry age related macular degeneration. Results from the Toronto and Oak Ridge Photobimodulation Study in AMD (TORPA). Invest Ophthalmol Vis Sci. 2012;53:2049\u0026ndash;2049.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMarkowitz SN, Devenyi RG, Munk MR, Croissant CL, Tedford SE, Ruckert R, Walker MG, Patino BE, Chen L, Nido M, Tedford CE. A double-masked, randomized, sham-controlled, single-center study with photobiomodulation for the treatment of dry age-related macular degeneration. Retina. 2020;40:1471\u0026ndash;82.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBurton B, Parodi MB, Jurgens I, Zanlonghi X, Hornan D, Roider J, Lorenz K, Munk MR, Croissant CL, Tedford SE, Walker M, Ruckert R, Tedford CE. LIGHTSITE II randomized multicenter trial: evaluation of multiwavelength photobiomodulation in non-exudative age-related macular degeneration. Ophthalmol Ther. 2023;12:953\u0026ndash;68.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMerry GF, Munk MR, Dotson RS, Walker MG, Devenyi RG. Photobiomodulation reduces drusen volume and improves visual acuity and contrast sensitivity in dry age-related macular degeneration. Acta Ophthalmol. 2017;95:e270\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHenschel A, Spital G, Lommatzsch A et al. Optical coherence tomography in neovascular age related macular degeneration compared to fluorescein angiography and visual acuity. Eur J Ophthalmol. 2009 Sep-Oct;19(5):831\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTing TD, Oh M, Cox TA et al. Decreased visual acuity associated with cystoid macular edema in neovascular age-related macular degeneration. Arch Ophthalmol. 2002;120(6):731\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Graph 1","content":"\u003cp\u003eGraph 1 is available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"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":"AMD, PBM","lastPublishedDoi":"10.21203/rs.3.rs-7870411/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7870411/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eAim\u003c/h2\u003e\u003cp\u003eTo evaluate the effectiveness and reliability of photobiomodulation (PBM) in the treatment of dry age-related macular degeneration (AMD).\u003c/p\u003e\u003ch2\u003eMaterial and Method:\u003c/h2\u003e\u003cp\u003eThe records of the 57 eyes of 34 cases consisting of 19 (55.9%) females and 15 (44.1%) males who had undergone PBM for dry AMD at the İstanbul Pendik Sistemg\u0026ouml;z Medical center were retrospectively evaluated.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eThe number of eyes with records at the 1st, 3rd and 6th month respectively was 57, 57, and 55. The best-corrected visual acuity (BCVA) before PBM was 0.360\u0026thinsp;\u0026plusmn;\u0026thinsp;0.031 and was found to be significantly higher than baseline in the 1st month with 0.481\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039, 3rd month with 0.470\u0026thinsp;\u0026plusmn;\u0026thinsp;0.038, and the 6th month with 0.419\u0026thinsp;\u0026plusmn;\u0026thinsp;0.036 (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The rate of vision increase following PBM was 59.6% in the 1st month, 61.4% in the 3rd month, and 43.9% in the 6th month. There was no significant difference in the central retinal thickness (CRT) or central retinal volume (CRV) values at any period of the follow-up duration. The only complication following PBM was conversion to wet AMD in the first month in one case. The long session duration, the need for regular application, and the relatively high cost were found to be the main disadvantages.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003ePBM is an effective and reliable method in the treatment of dry AMD. However, it also has significant disadvantages.\u003c/p\u003e","manuscriptTitle":"Photobiomodulation in the Treatment of Dry Age-Related Macular Degeneration: Effectiveness, Advantages, and Disadvantages","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-05 06:32:15","doi":"10.21203/rs.3.rs-7870411/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-12-06T08:25:15+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-28T08:37:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"117197595604728385890462467097099761888","date":"2025-10-23T16:32:31+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-23T12:51:44+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-21T02:10:53+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-21T02:10:06+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Ophthalmology","date":"2025-10-15T16:48:16+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":"d4353ae9-677b-4a8c-a014-1c6fa957028e","owner":[],"postedDate":"November 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-12-24T10:53:14+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-05 06:32:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7870411","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7870411","identity":"rs-7870411","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}