Atypical optic neuritis related to dental affection: A case report

Atypical optic neuritis related to dental affection: A case report | 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 Case Report Atypical optic neuritis related to dental affection: A case report Nicolas Owlya, Emmanuelle Moret, Bao Khanh Tran This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8921266/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 12 You are reading this latest preprint version Abstract Background: Optic neuritis may arise from multiple aetiologies, including inflammatory, autoimmune, and infectious causes. Few authors have described a possible link between dental diseases and optic neuritis, although this relationship remains poorly defined due to its rarity. We report a case of unilateral atypical optic neuritis possibly secondary to an approximal caries of the ipsilateral upper jaw. Case presentation: A 43-year-old Caucasian woman with no relevant past medical history presented with unilateral blurred vision, photophobia and ipsilateral temporal headache. Ophtalmic examination revealed anterior optic neuritis in the affected eye. Extensive investigations failed to identified any common underlying aetiology. Neither objective nor subjective change was observed following high-dose intravenous corticosteroids. Remarkably, signs and symptoms resolved spontaneously after extraction of an asymptomatic approximal caries in the ipsilateral maxilla, identified incidentally by a routine dental radiography. While the peripapillary retinal nerve fiber layer remained unchanged during the first two months, optic disc edema gradually improved over the six months following tooth extraction. Conclusions: Dental infection might be a rare and likely underdiagnosed aetiology of idiopathic atypical optic neuritis, and should be considered when no other cause is identified. Although the exact pathophysiology hasn’t been unveiled, several hypotheses have been proposed, warranting further investigation. atypical optic neuritis dental disease approximal caries Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Background Optic neuritis is an acute inflammatory optic neuropathy, typically presenting with variable visual acuity or visual field loss, dyschromatopsia, periocular pain exacerbated with eye movement, and a relative afferent pupillary defect. The “typical” or “demyelinating” form is mostly associated with multiple sclerosis, although it might also occur idiopathically. In contrast, “atypical” optic neuritis presents with features that deviate from the classical presentation, including occurrence in males, age under 18 or over than 50 years, absence of periocular pain, bilateral involvement, severe vision loss, progression of visual loss beyond two weeks, lack of spontaneous or corticosteroid-induced improvement, or marked disc swelling(1). The distinction between these two entities is important as their aetiology differs. The differential diagnosis of atypical of optic neuritis includes neuromyelitis optica spectrum disorder (NMOSD), anti-myelin oligodendrocyte glycoprotein (anti-MOG) associated optic neuritis, chronic relapsing inflammatory optic neuritis, sarcoidosis, granulomatosis with polyangiitis, systemic lupus erythematosus, antiphospholipid antibody syndrome, Sjogren syndrome, primary central nervous system vasculitis, and infectious causes such as syphilis, tuberculosis, human immunodeficiency virus, Lyme disease, Bartonella, herpesviruses and West Nile virus)(1). Atypical optic neuritis of rhinogenic origin has also been reported, likely explained by the close anatomical relationship between the paranasal sinuses and the orbital cavity housing the optic nerve. Furthermore, several case reports suggest that dental diseases without associated sinusitis may also be implicated in optic neuritis(2–4), although this remains insufficiently established. We report a case of a patient with a unilateral atypical optic neuritis, possibly secondary to an approximal carious lesion of the ipsilateral maxilla. Case presentation A previously healthy 43-year-old Caucasian woman presented with a two-week history of blurred vision in the temporal visual field of the right eye, predominantly in the morning and exacerbated by heat exposure (Uhthoff’s phenomenon). The visual symptoms were associated with photophobia and right temporal headache. Best-corrected visual acuity was 20/16 in the right eye (S + 2.25 C -0.75/160°) and 20/12.5 in the left eye (S + 1.0 C -0.50/160°), with the right eye being more hyperopic by around + 1.50D than the left eye. No dyschromatopsia (17/17 on Ishihara plates in both eyes), but subjective red desaturation was observed on the right eye. Pupils were symmetrical with no relative afferent pupillary defect. Ocular movements were unrestricted, but increased the right periorbital pain. Intraocular pressure and slit lamp examination were normal in both eyes. Right eye fundus examination revealed a diffuse swelling of the optic disc consistent with optic disc edema on the right eye. Left eye fundus was unremarkable. Automated visual field (Octopus, Interzeag AG, program G2) showed a slight annular decrease in light sensitivity in the right eye only. Optical coherence tomography (OCT, Spectralis, Heidelberg Engineering) revealed an increase in the peripapillary retinal nerve fiber layer (pRNFL) thickness in the right eye. The pRNFL in the left eye and the maculae on both sides were normal. (Fig. 1 A). Brain and orbit magnetic resonance imaging (MRI) revealed a FLAIR hyperintensity with contrast enhancement and oedema of the right optic nerve, consistent with optic neuritis. In addition, posterior flattening of the globe, likely secondary to nerve inflammation, explained the right eye’s hyperopia (Fig. 2 ). No other intracerebral lesion was found, in particular no demyelinating lesion. Blood tests with complete blood count, inflammatory markers, angiotensin-converting enzyme, syphilis/Lyme/Bartonella serology and T-Spot-TB were unremarkable. The biological work-up did not include anti-NMO and anti-MOG antibodies at that moment. Over the first two weeks, no clinical improvement was observed. The persistence of symptoms, combined with a significant optic disc edema, led to the diagnosis of atypical optic neuritis. At the third week, the patient received a five-day course of oral prednisone (20 mg once daily), which had no effect on either clinical symptoms or global RNFL thickness. After seven weeks, high-dose intravenous corticosteroid therapy was initiated (methylprednisolone 1g per day for 2 days), followed by oral tapering over two weeks, also without any effect on the clinical picture. Surprisingly, 30 minutes after each intravenous administration of methylprednisolone, the patient developed transient right-sided facial oedema, along with exacerbated headache and nausea, lasting for one hour; however, clinical pharmacology assessment did not establish a causal relationship with the drug. One month later, the patient underwent a routine dental examination, during which an approximal caries was found on tooth 18 in the upper right quadrant (Fig. 3 ). The affected tooth was removed without any additional treatment, including antibiotics. Clinical symptoms began to improve within a few days following tooth extraction. Two months later, automated visual field testing demonstrated a reduction in the annular defect, despite a stable mean deviation (Fig. 4 ). During the first two months of follow-up, peripapillary retinal nerve fiber layer (pRNFL) thickness and optic disc edema remained stable. In contrast, progressive improvement in both parameters was observed within days following tooth extraction (Fig. 5 ). At eight months, pRNFL thickness was symmetrical compared with the contralateral eye (Fig. 1 B). Optic disc edema continued to resolve gradually, with near-complete resolution observed at 25 months (Fig. 1 C). Discussion and conclusions Although rare, ocular manifestations of dental origin have been described. In a large series, Bocca et al. found a significant correlation between dental foci and ocular diseases in patients between 15 and 30 years, with a stronger association for maxillary teeth and for uveitis compared to optic neuritis. Most frequently, the odontogenic infections give rise to sinusitis and may progress to orbital cellulitis or abscess formation, which can in turn cause secondary inflammation of the optic nerve(5). Optic neuritis directly related to sinusitis, without orbital involvement, appears to be even rarer(6). Beyond these rhinogenic mechanisms, a more direct link between dental pathology and optic neuropathies has been proposed, potentially involving different pathophysiological pathways. Several case reports support this association. Ravault et al. described a 21-year-old man with papillitis with a concomitant infected premolar and a chronic tonsillitis(2). Systemic work up did not highlight any other aetiology, and the vision improved after surgical management of both lesions. The authors suggested an infectious optic neuritis of focal origin, although specific role of the infected premolar was compromised by the concomitant tonsillectomy. Passi et al. reported two patients with retrobulbar optic neuritis associated with dental disease. In the first case, a 38-year-old woman suffered from multiple apical caries and poor dental hygiene, with no associated systemic condition. In the second case, a 55-years-old man developed retrobulbar optic neuritis concurrently with alveolitis following the extraction of a dental caries. In both cases, optic neuritis improved after systemic antibiotic therapy, corticosteroids and surgical therapy(3). Similarly, Chaabouni et al. published a series of four patients with unilateral atypical optic neuritis associated with dental disease: an infected wisdom tooth, suppurative periodontitis of a premolar with gingival congestion, necrosis of an upper premolar complicated by maxillary sinusitis, and a deep molar caries. In all cases, systemic antibiotics and corticosteroids, in addition to treatment of the dental disease, led to resolution of the optic neuritis(4). Taken together, these reports highlight the possibility of dental foci acting as a trigger for optic neuritis. In our case, several aspects could argue against a dental origin. The lesion was an asymptomatic approximal caries, raising the possibility of a coincidental finding. Serological testing for anti-aquaporin-4 (NMO-IgG) and anti-MOG antibodies was not performed; however, brain and orbit MRI showed no other lesions and the patient exhibited none of the neurological features typically associated with NMOSD. Notably, high-dose corticosteroids failed to improve the clinical picture and instead provoked transient ipsilateral hemifacial oedema after each infusion, suggesting a localized inflammatory susceptibility. Most importantly, progressive recovery was observed only after extraction of the affected tooth, further supporting a causal relationship. Several mechanisms have been proposed to explain the link between dental disease and optic neuritis. A first possibility is direct contiguous spread of infection, either through periosteal pathways or via the maxillary sinus. In such a scenario, only ipsilateral maxillary foci would be expected to play a role. However, some published cases involved mandibular or even contralateral lesions, making this mechanism insufficient to explain all observations. A second hypothesis is hematogenous dissemination of microorganisms from the dental focus to the optic nerve, although this seems less likely in the absence of orbital cellulitis or abscess. More plausibly in our case, a focal allergic mechanism could be involved: microbial antigens from the dental focus may diffuse into the systemic circulation and trigger an immune-mediated inflammatory response, leading to lymphocytic infiltration of the optic nerve. In this model, it is the presence of the dental focus itself that matters, rather than its exact anatomical location(3,5,7). These mechanisms are hypothetical and have not yet been confirmed by experimental or clinical studies. In conclusion, this case suggests that dental affection may represent a potential aetiology for idiopathic atypical optic neuritis. Although the precise pathophysiological mechanisms remain hypothetical, our observation, together with previously reported cases, highlights the importance of considering dental foci in patients with atypical optic neuritis, particularly when conventional treatments are ineffective. Early identification and management of dental sources may improve visual outcomes and reduce the risk of recurrence. Abbreviations Anti- MOG anti-myelin oligodendrocyte glycoprotein MRI magnetic resonance imaging NMOSD neuromyelitis optica spectrum disorder OCT Optical coherence tomography pRNFL peripapillary retinal nerve fiber layer Declarations Ethics approval and consent to participate Ethics approval was not required for this case report in accordance with local and institutional guidelines. Written informed consent was obtained from the patient for participation. Consent for publication Written informed consent was obtained from the patient for publication of this case report and any accompanying images. Competing interests The authors declare that they have no competing interests Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Author Contribution NO and EM drafted the manuscript. EM collected the clinical data. BT critically reviewed and revised the manuscript. All authors read and approved the final manuscript. Acknowledgements Not applicable. Data Availability All data generated or analysed during this study are included in this published article and its supplementary information files. References Abel A, McClelland C, Lee MS. Critical review: Typical and atypical optic neuritis. Surv Ophthalmol. nov 2019;64(6):770‑9. Ravault MP, Hullo A, Giffon D. [A case of papillitis of probable focal origin]. Bull Soc Ophtalmol Fr. janv 1986;86(1):73‑4, 76. Passi P, Perrone S, Musajo F, Frezza F. [A rare complication of odontogenic infection: retrobulbar optical neuritis (description of 2 cases)]. G Stomatol Ortognatodonzia. 1983;2(3):129‑32. Chaabouni M, Hachicha L, Ben Hadj Hamida F, Chebihi S. [Optic neuropathy of dental origin. Apropos of 4 cases]. Rev Stomatol Chir Maxillofac. 1991;92(4):259‑61. Biagojević M, Stefanović B, Piščević P, Radosavljević M. Phlegmon de l’orbite d’origine dentaire. Ophthalmologica. 1969;157(1):14‑23. Vu Q, Dyer G, Kunjukunju N. A rare case of odontogenic parainfectious intraorbital optic neuritis with the absence of clinical manifestation of orbital cellulitis. Retin Cases Brief Rep. 2015;9(3):205‑9. Bocca M, Zombolo L, Coscia D, Moniaci D. [The correlation between dental pathology and ophthalmic pathology]. Minerva Stomatol. oct 1989;38(10):1117‑20. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 30 Apr, 2026 Reviews received at journal 07 Apr, 2026 Reviewers agreed at journal 22 Mar, 2026 Reviews received at journal 18 Mar, 2026 Reviews received at journal 18 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviewers invited by journal 17 Mar, 2026 Editor invited by journal 23 Feb, 2026 Editor assigned by journal 21 Feb, 2026 Submission checks completed at journal 21 Feb, 2026 First submitted to journal 19 Feb, 2026 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-8921266","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":607729093,"identity":"3aa1e9d5-c797-47a6-891c-3d4961376448","order_by":0,"name":"Nicolas Owlya","email":"","orcid":"","institution":"Hôpital Ophtalmique Jules-Gonin","correspondingAuthor":false,"prefix":"","firstName":"Nicolas","middleName":"","lastName":"Owlya","suffix":""},{"id":607729095,"identity":"35c23a75-fb16-48b5-a945-14656a5ec0d5","order_by":1,"name":"Emmanuelle Moret","email":"","orcid":"","institution":"Cabinet d’ophtalmologie de la Combe","correspondingAuthor":false,"prefix":"","firstName":"Emmanuelle","middleName":"","lastName":"Moret","suffix":""},{"id":607729101,"identity":"710c3c42-750c-49f4-b957-bf6cd9873d16","order_by":2,"name":"Bao Khanh Tran","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABCElEQVRIiWNgGAWjYBACAwYGZmYgnQDhVgAxkHsAKkVACxuIe4ZkLYxtqFJYgTn74cPGBTV38hjkex9+Lpx3mMHgOPvDAx93MMib49Bi2ZOWnDzj2LNiBjZ2Y+mZ24BaDvMYHJx5hsFwZwMOhx3IMT7Mw3Y4sYGNjUGad9vh+pnNPAyHedsYEgwO4NBy/g1Qyz+wFubfvHMOM0g2sz/Ar+VGjnEybxtYC5s0b8NhBn5moNvwabGc8SzZmLfvcGIbWxqbNc+xdKAWkF/aJAw34NBizp98WJrn2+HEfuZjzLd5aqwZ2PiPP/7wsc1GHpctcMAGoZphfAkC6hGgjmiVo2AUjIJRMHIAAFcPVQybJ9uUAAAAAElFTkSuQmCC","orcid":"","institution":"Y-Vision Eye Center","correspondingAuthor":true,"prefix":"","firstName":"Bao","middleName":"Khanh","lastName":"Tran","suffix":""}],"badges":[],"createdAt":"2026-02-19 23:38:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8921266/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8921266/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104998252,"identity":"a1253743-5114-4522-8469-42089a069095","added_by":"auto","created_at":"2026-03-19 16:25:58","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1280739,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eOptical coherence tomography findings during follow-up.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA. Baseline bilateral peripapillary retinal nerve fiber layer (pRNFL) analysis. The right eye shows an increase in pRNFL thickness with relative sparing of the temporal sector, consistent with optic disc edema, while the left eye demonstrates normal pRNFL thickness.\u003c/p\u003e\n\u003cp\u003eB. Bilateral pRNFL analysis after 8 months of follow-up and 6 months after tooth extraction, showing symmetrical pRNFL thickness in both eyes.\u003c/p\u003e\n\u003cp\u003eC. Bilateral pRNFL analysis after 25 months of follow-up and 20 months after tooth extraction, showing persistent symmetrical pRNFL thickness.\u003c/p\u003e\n\u003cp\u003eFor each panel (A–C), OCT pRNFL thickness maps are shown in the upper right, infrared fundus images of the optic disc in the upper left, and sectorial pRNFL thickness profiles in the lower panel.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8921266/v1/9dd250a0f03274248ef6b5b6.png"},{"id":104998245,"identity":"2d15dbcf-661c-4e08-b8e1-f9477b91b458","added_by":"auto","created_at":"2026-03-19 16:25:56","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":796497,"visible":true,"origin":"","legend":"\u003cp\u003eBrain and orbit MRI of the patient.\u003c/p\u003e\n\u003cp\u003eA, B. Axial and coronal FLAIR sequences showing increased signal intensity of the right optic nerve (white arrows).\u003c/p\u003e\n\u003cp\u003eC. Axial T2-weighted sequence showing posterior flattening of the right ocular globe (white arrow).\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8921266/v1/33d770ab65c640d729b5ae71.png"},{"id":104998262,"identity":"8ca7447c-b5dc-4494-be2b-b28e4afc9fff","added_by":"auto","created_at":"2026-03-19 16:26:00","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":39117,"visible":true,"origin":"","legend":"\u003cp\u003eFrontal dental radiograph (X-ray) showing an approximal caries on the tooth 18 in the upper right quadrant (white arrow).\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8921266/v1/f0241706262ee5949ecfa194.jpg"},{"id":104998287,"identity":"7c44e8aa-0e8f-4e30-8e10-394cf9105ba5","added_by":"auto","created_at":"2026-03-19 16:26:14","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":196492,"visible":true,"origin":"","legend":"\u003cp\u003eAutomated visual field changes in the right eye during follow-up.\u003c/p\u003e\n\u003cp\u003eAutomated 60° visual field testing of the right eye at day 2 (A) and 4.5 months (B) demonstrates reduction of the annular defect over time.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-8921266/v1/24405988b170b509b310e353.png"},{"id":104998331,"identity":"931a2ec8-f8e3-4098-923a-fe01553d70eb","added_by":"auto","created_at":"2026-03-19 16:26:29","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":111763,"visible":true,"origin":"","legend":"\u003cp\u003eLongitudinal follow-up of global RNFL thickness from baseline (M0) to M8. Vertical lines indicate interventions: Prednisone per os (5 days at 20 mg/day), Methylprednisolone IV (1 g/day for 2 days), and Tooth removal.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-8921266/v1/b9ec4632e9f5d9bcacfce6a9.png"},{"id":105035719,"identity":"b3518ceb-917d-4445-b52b-b36f288b4b72","added_by":"auto","created_at":"2026-03-20 07:26:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2632717,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8921266/v1/1ece0256-7db9-4ece-b843-273d3c93337b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Atypical optic neuritis related to dental affection: A case report","fulltext":[{"header":"Background","content":"\u003cp\u003eOptic neuritis is an acute inflammatory optic neuropathy, typically presenting with variable visual acuity or visual field loss, dyschromatopsia, periocular pain exacerbated with eye movement, and a relative afferent pupillary defect. The \u0026ldquo;typical\u0026rdquo; or \u0026ldquo;demyelinating\u0026rdquo; form is mostly associated with multiple sclerosis, although it might also occur idiopathically.\u003c/p\u003e \u003cp\u003eIn contrast, \u0026ldquo;atypical\u0026rdquo; optic neuritis presents with features that deviate from the classical presentation, including occurrence in males, age under 18 or over than 50 years, absence of periocular pain, bilateral involvement, severe vision loss, progression of visual loss beyond two weeks, lack of spontaneous or corticosteroid-induced improvement, or marked disc swelling(1). The distinction between these two entities is important as their aetiology differs.\u003c/p\u003e \u003cp\u003eThe differential diagnosis of atypical of optic neuritis includes neuromyelitis optica spectrum disorder (NMOSD), anti-myelin oligodendrocyte glycoprotein (anti-MOG) associated optic neuritis, chronic relapsing inflammatory optic neuritis, sarcoidosis, granulomatosis with polyangiitis, systemic lupus erythematosus, antiphospholipid antibody syndrome, Sjogren syndrome, primary central nervous system vasculitis, and infectious causes such as syphilis, tuberculosis, human immunodeficiency virus, Lyme disease, Bartonella, herpesviruses and West Nile virus)(1).\u003c/p\u003e \u003cp\u003eAtypical optic neuritis of rhinogenic origin has also been reported, likely explained by the close anatomical relationship between the paranasal sinuses and the orbital cavity housing the optic nerve. Furthermore, several case reports suggest that dental diseases without associated sinusitis may also be implicated in optic neuritis(2\u0026ndash;4), although this remains insufficiently established.\u003c/p\u003e \u003cp\u003eWe report a case of a patient with a unilateral atypical optic neuritis, possibly secondary to an approximal carious lesion of the ipsilateral maxilla.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eA previously healthy 43-year-old Caucasian woman presented with a two-week history of blurred vision in the temporal visual field of the right eye, predominantly in the morning and exacerbated by heat exposure (Uhthoff’s phenomenon). The visual symptoms were associated with photophobia and right temporal headache.\u003c/p\u003e \u003cp\u003eBest-corrected visual acuity was 20/16 in the right eye (S + 2.25 C -0.75/160°) and 20/12.5 in the left eye (S + 1.0 C -0.50/160°), with the right eye being more hyperopic by around + 1.50D than the left eye. No dyschromatopsia (17/17 on Ishihara plates in both eyes), but subjective red desaturation was observed on the right eye. Pupils were symmetrical with no relative afferent pupillary defect. Ocular movements were unrestricted, but increased the right periorbital pain. Intraocular pressure and slit lamp examination were normal in both eyes. Right eye fundus examination revealed a diffuse swelling of the optic disc consistent with optic disc edema on the right eye. Left eye fundus was unremarkable.\u003c/p\u003e \u003cp\u003eAutomated visual field (Octopus, Interzeag AG, program G2) showed a slight annular decrease in light sensitivity in the right eye only. Optical coherence tomography (OCT, Spectralis, Heidelberg Engineering) revealed an increase in the peripapillary retinal nerve fiber layer (pRNFL) thickness in the right eye. The pRNFL in the left eye and the maculae on both sides were normal. (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eBrain and orbit magnetic resonance imaging (MRI) revealed a FLAIR hyperintensity with contrast enhancement and oedema of the right optic nerve, consistent with optic neuritis. In addition, posterior flattening of the globe, likely secondary to nerve inflammation, explained the right eye’s hyperopia (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). No other intracerebral lesion was found, in particular no demyelinating lesion.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eBlood tests with complete blood count, inflammatory markers, angiotensin-converting enzyme, syphilis/Lyme/Bartonella serology and T-Spot-TB were unremarkable. The biological work-up did not include anti-NMO and anti-MOG antibodies at that moment.\u003c/p\u003e \u003cp\u003eOver the first two weeks, no clinical improvement was observed. The persistence of symptoms, combined with a significant optic disc edema, led to the diagnosis of atypical optic neuritis.\u003c/p\u003e \u003cp\u003eAt the third week, the patient received a five-day course of oral prednisone (20 mg once daily), which had no effect on either clinical symptoms or global RNFL thickness. After seven weeks, high-dose intravenous corticosteroid therapy was initiated (methylprednisolone 1g per day for 2 days), followed by oral tapering over two weeks, also without any effect on the clinical picture. Surprisingly, 30 minutes after each intravenous administration of methylprednisolone, the patient developed transient right-sided facial oedema, along with exacerbated headache and nausea, lasting for one hour; however, clinical pharmacology assessment did not establish a causal relationship with the drug.\u003c/p\u003e \u003cp\u003eOne month later, the patient underwent a routine dental examination, during which an approximal caries was found on tooth 18 in the upper right quadrant (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). The affected tooth was removed without any additional treatment, including antibiotics.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eClinical symptoms began to improve within a few days following tooth extraction. Two months later, automated visual field testing demonstrated a reduction in the annular defect, despite a stable mean deviation (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). During the first two months of follow-up, peripapillary retinal nerve fiber layer (pRNFL) thickness and optic disc edema remained stable. In contrast, progressive improvement in both parameters was observed within days following tooth extraction (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). At eight months, pRNFL thickness was symmetrical compared with the contralateral eye (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eB). Optic disc edema continued to resolve gradually, with near-complete resolution observed at 25 months (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eC).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e "},{"header":"Discussion and conclusions","content":"\u003cp\u003eAlthough rare, ocular manifestations of dental origin have been described. In a large series, Bocca et al. found a significant correlation between dental foci and ocular diseases in patients between 15 and 30 years, with a stronger association for maxillary teeth and for uveitis compared to optic neuritis.\u003c/p\u003e\u003cp\u003eMost frequently, the odontogenic infections give rise to sinusitis and may progress to orbital cellulitis or abscess formation, which can in turn cause secondary inflammation of the optic nerve(5). Optic neuritis directly related to sinusitis, without orbital involvement, appears to be even rarer(6). Beyond these rhinogenic mechanisms, a more direct link between dental pathology and optic neuropathies has been proposed, potentially involving different pathophysiological pathways. Several case reports support this association.\u003c/p\u003e\u003cp\u003eRavault et al. described a 21-year-old man with papillitis with a concomitant infected premolar and a chronic tonsillitis(2). Systemic work up did not highlight any other aetiology, and the vision improved after surgical management of both lesions. The authors suggested an infectious optic neuritis of focal origin, although specific role of the infected premolar was compromised by the concomitant tonsillectomy.\u003c/p\u003e\u003cp\u003ePassi et al. reported two patients with retrobulbar optic neuritis associated with dental disease. In the first case, a 38-year-old woman suffered from multiple apical caries and poor dental hygiene, with no associated systemic condition. In the second case, a 55-years-old man developed retrobulbar optic neuritis concurrently with alveolitis following the extraction of a dental caries. In both cases, optic neuritis improved after systemic antibiotic therapy, corticosteroids and surgical therapy(3).\u003c/p\u003e\u003cp\u003eSimilarly, Chaabouni et al. published a series of four patients with unilateral atypical optic neuritis associated with dental disease: an infected wisdom tooth, suppurative periodontitis of a premolar with gingival congestion, necrosis of an upper premolar complicated by maxillary sinusitis, and a deep molar caries. In all cases, systemic antibiotics and corticosteroids, in addition to treatment of the dental disease, led to resolution of the optic neuritis(4). Taken together, these reports highlight the possibility of dental foci acting as a trigger for optic neuritis.\u003c/p\u003e\u003cp\u003eIn our case, several aspects could argue against a dental origin. The lesion was an asymptomatic approximal caries, raising the possibility of a coincidental finding. Serological testing for anti-aquaporin-4 (NMO-IgG) and anti-MOG antibodies was not performed; however, brain and orbit MRI showed no other lesions and the patient exhibited none of the neurological features typically associated with NMOSD. Notably, high-dose corticosteroids failed to improve the clinical picture and instead provoked transient ipsilateral hemifacial oedema after each infusion, suggesting a localized inflammatory susceptibility. Most importantly, progressive recovery was observed only after extraction of the affected tooth, further supporting a causal relationship.\u003c/p\u003e\u003cp\u003eSeveral mechanisms have been proposed to explain the link between dental disease and optic neuritis. A first possibility is direct contiguous spread of infection, either through periosteal pathways or via the maxillary sinus. In such a scenario, only ipsilateral maxillary foci would be expected to play a role. However, some published cases involved mandibular or even contralateral lesions, making this mechanism insufficient to explain all observations. A second hypothesis is hematogenous dissemination of microorganisms from the dental focus to the optic nerve, although this seems less likely in the absence of orbital cellulitis or abscess. More plausibly in our case, a focal allergic mechanism could be involved: microbial antigens from the dental focus may diffuse into the systemic circulation and trigger an immune-mediated inflammatory response, leading to lymphocytic infiltration of the optic nerve. In this model, it is the presence of the dental focus itself that matters, rather than its exact anatomical location(3,5,7). These mechanisms are hypothetical and have not yet been confirmed by experimental or clinical studies.\u003c/p\u003e\u003cp\u003eIn conclusion, this case suggests that dental affection may represent a potential aetiology for idiopathic atypical optic neuritis. Although the precise pathophysiological mechanisms remain hypothetical, our observation, together with previously reported cases, highlights the importance of considering dental foci in patients with atypical optic neuritis, particularly when conventional treatments are ineffective. Early identification and management of dental sources may improve visual outcomes and reduce the risk of recurrence.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eAnti- MOG\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eanti-myelin oligodendrocyte glycoprotein\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003emagnetic resonance imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eNMOSD\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eneuromyelitis optica spectrum disorder\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eOCT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eOptical coherence tomography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003epRNFL\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eperipapillary retinal nerve fiber layer\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e \u003cp\u003eEthics approval was not required for this case report in accordance with local and institutional guidelines. Written informed consent was obtained from the patient for participation.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent for publication\u003c/strong\u003e \u003cp\u003eWritten informed consent was obtained from the patient for publication of this case report and any accompanying images.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eCompeting interests\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no competing interests\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eNO and EM drafted the manuscript. EM collected the clinical data. BT critically reviewed and revised the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAll data generated or analysed during this study are included in this published article and its supplementary information files.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003e Abel A, McClelland C, Lee MS. Critical review: Typical and atypical optic neuritis. Surv Ophthalmol. nov 2019;64(6):770‑9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e Ravault MP, Hullo A, Giffon D. [A case of papillitis of probable focal origin]. Bull Soc Ophtalmol Fr. janv 1986;86(1):73‑4, 76.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e Passi P, Perrone S, Musajo F, Frezza F. [A rare complication of odontogenic infection: retrobulbar optical neuritis (description of 2 cases)]. G Stomatol Ortognatodonzia. 1983;2(3):129‑32.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e Chaabouni M, Hachicha L, Ben Hadj Hamida F, Chebihi S. [Optic neuropathy of dental origin. Apropos of 4 cases]. Rev Stomatol Chir Maxillofac. 1991;92(4):259‑61.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e Biagojević M, Stefanović B, Piščević P, Radosavljević M. Phlegmon de l\u0026rsquo;orbite d\u0026rsquo;origine dentaire. Ophthalmologica. 1969;157(1):14‑23.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e Vu Q, Dyer G, Kunjukunju N. A rare case of odontogenic parainfectious intraorbital optic neuritis with the absence of clinical manifestation of orbital cellulitis. Retin Cases Brief Rep. 2015;9(3):205‑9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e Bocca M, Zombolo L, Coscia D, Moniaci D. [The correlation between dental pathology and ophthalmic pathology]. Minerva Stomatol. oct 1989;38(10):1117‑20.\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":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"atypical optic neuritis, dental disease, approximal caries","lastPublishedDoi":"10.21203/rs.3.rs-8921266/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8921266/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Optic neuritis may arise from multiple aetiologies, including inflammatory, autoimmune, and infectious causes. Few authors have described a possible link between dental diseases and optic neuritis, although this relationship remains poorly defined due to its rarity. We report a case of unilateral atypical optic neuritis possibly secondary to an approximal caries of the ipsilateral upper jaw.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase presentation:\u003c/strong\u003e A 43-year-old Caucasian woman with no relevant past medical history presented with unilateral blurred vision, photophobia and ipsilateral temporal headache. Ophtalmic examination revealed anterior optic neuritis in the affected eye. Extensive investigations failed to identified any common underlying aetiology.\u003c/p\u003e\n\u003cp\u003eNeither objective nor subjective change was observed following high-dose intravenous corticosteroids. Remarkably, signs and symptoms resolved spontaneously after extraction of an asymptomatic approximal caries in the ipsilateral maxilla, identified incidentally by a routine dental radiography. While the peripapillary retinal nerve fiber layer remained unchanged during the first two months, optic disc edema gradually improved over the six months following tooth extraction.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e Dental infection might be a rare and likely underdiagnosed aetiology of idiopathic atypical optic neuritis, and should be considered when no other cause is identified. Although the exact pathophysiology hasn’t been unveiled, several hypotheses have been proposed, warranting further investigation.\u003c/p\u003e","manuscriptTitle":"Atypical optic neuritis related to dental affection: A case report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-19 16:24:44","doi":"10.21203/rs.3.rs-8921266/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-30T07:22:36+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-07T21:31:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"60879873462783005743215217981520838631","date":"2026-03-22T11:57:15+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-19T02:42:27+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-18T12:20:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"238288001413318378166781050116381260938","date":"2026-03-17T15:46:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"267891727055558588115964937187441562288","date":"2026-03-17T07:58:26+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-17T07:30:19+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-23T07:33:06+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-21T11:43:10+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-21T11:42:15+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Ophthalmology","date":"2026-02-19T23:32:57+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8b181c89-cec1-4c01-9778-9b4eab283533","owner":[],"postedDate":"March 19th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-04-30T07:22:36+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-04-30T07:38:15+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-19 16:24:44","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8921266","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8921266","identity":"rs-8921266","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}