Visual Outcomes in Acute Methyl Alcohol poisoning and its Biochemical Predictors: A Hospital-Based Study in Eastern India

Abstract

Acute methyl alcohol toxicity can lead to severe ocular morbidity. In the present study, we aimed to observe the ocular outcomes in acute methyl alcohol poisoning and determine the biochemical predictors of the final visual outcome. This was a hospital- based descriptive study conducted on 19 consecutive patients of acute methanol poisoning presenting to the Ophthalmology department of a tertiary care multispecialty hospital in Eastern India. Thorough clinical history was obtained in each case.  A comprehensive ocular examination was done. Details of systemic treatment provided were obtained in all cases. Nineteen patients were included in the study. All patients were males. The average age of patients was 35.84 ± 9.25 years. All patients complained of bilateral blurring of vision. One patient had severe vision loss with visual acuity of hand movements in both eyes. . Colour vision was absent in 7 eyes (18.41%), and impaired in 5 eyes (13.15%). Disc edema was seen in 5 eyes (13.15%). High anion gap metabolic acidosis was seen in 13 (78.9%) cases. Serum bicarbonate level was < 22 mmol L^-1 in 13 (68.42%) patients. Eleven (57.89%) patients underwent hemodialysis. The presence of metabolic acidosis, high anion gap, and high base deficit were associated with poor visual acuity and defective color vision both at the initial presentation and final follow-up. Metabolic acidosis, high anion gap, and base deficit at the time of presentation are associated with defective color vision, abnormal pupillary reaction, and poor vision both during initial and final visits. Prompt management of these metabolic abnormalities can decrease ocular morbidity and improve the final visual outcomes.