Methanol poisoning: ocular and neurological manifestations

Abstract

Purpose: The purpose of this study was to examine the effectiveness of ethanol and high-dose intravenous steroid for preserving vision in acute methanol poisoning.

Methods: Eight cases of acute methanol poisoning presented to the emergency department. Detailed physical examination including neurological assessment was performed. Detailed ocular examinations were performed including visually evoked potential and electroretinography in indicated cases. All patients had visual symptoms. Pupillary abnormality was observed in all. Edema of the optic disc and nerve fiber layer were common fundus findings. The majority of cases were treated with methylprednisolone intravenously. Ethanol was given intravenously in four cases who presented within 48 h. Hemodialysis was performed in two cases having neurological manifestations and metabolic acidosis. Sodium bicarbonate was given to four patients. Folinic acid and multivitamins were also given to all the patients based on neurological advice.

Results: Most of the patients showed a good response to the treatment. In 87.5% of the cases, improvements in visual acuity of at least two lines were noted in follow-up visits.

Conclusions: Early presentation with prompt treatment has a significant role in preserving and improving visual acuity. Ethanol and high-dose intravenous methylprednisolone can be an alternative treatment with better visual outcome where fomepizole is unavailable.