Alberto Galvez-Ruiz1, Sahar M Elkhamary2, Nasira Asghar3, Thomas M Bosley4. 1. Department of Ophthalmology, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. 2. Department of Diagnostic Imaging, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. 3. Department of Research, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. 4. Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
Abstract
PURPOSE: To assess the frequency and significance of optic disk cupping after methanol poisoning. METHODS: We retrospectively reviewed the medical records of 50 consecutive patients with methanol poisoning, including visual acuity, pupillary reaction, and optic disk features such as the presence and degree of cupping. All patients were examined in the chronic phase after optic nerve damage. RESULTS: Optic disk cupping ≥0.8 c/d was present in at least one eye of 22 of these 50 patients (43/100 eyes). Severity of cupping was statistically symmetric in the two eyes, and increasing severity of cupping was correlated with worse visual acuity (p=0.007) and increasing visual field loss. Degree of cupping was significantly correlated with increasing patient age but not with putaminal necrosis. CONCLUSIONS: Optic disk cupping after methanol poisoning may be more common than previously recognised. Cupping in this setting may reflect toxicity of methanol metabolites to axons and glial cells in the prelaminar, laminar and retrolaminar regions, and seems to be important as a marker for worse optic nerve damage. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
PURPOSE: To assess the frequency and significance of optic disk cupping after methanolpoisoning. METHODS: We retrospectively reviewed the medical records of 50 consecutive patients with methanolpoisoning, including visual acuity, pupillary reaction, and optic disk features such as the presence and degree of cupping. All patients were examined in the chronic phase after optic nerve damage. RESULTS: Optic disk cupping ≥0.8 c/d was present in at least one eye of 22 of these 50 patients (43/100 eyes). Severity of cupping was statistically symmetric in the two eyes, and increasing severity of cupping was correlated with worse visual acuity (p=0.007) and increasing visual field loss. Degree of cupping was significantly correlated with increasing patient age but not with putaminal necrosis. CONCLUSIONS: Optic disk cupping after methanolpoisoning may be more common than previously recognised. Cupping in this setting may reflect toxicity of methanol metabolites to axons and glial cells in the prelaminar, laminar and retrolaminar regions, and seems to be important as a marker for worse optic nerve damage. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.