Is optic nerve sheath diameter diagnostic in methanol intoxication?

Methyl alcohol intoxication causes severe morbidity and mortality, especially in developing countries. Formic acid is formed as a result of methanol metabolism. Formic acid accumulation and inhibition of adenosine triphosphate synthesis result in ophthalmic issues. This study aimed to demonstrate that the optic nerve sheath diameter (ONSD) measurement is an accurate prognostic marker and can be helpful in the diagnosis of methanol intoxication. This prospective study was conducted with 52 patients who were admitted to the emergency department after alcohol consumption and agreed to participate in the study. Age, gender, comorbid diseases, vital signs, ONSD ultrasonography measurements, hospitalization and discharge status, in-hospital mortality status, dialysis need, presence of visual impairment, blood gas parameters, respiratory status, time since alcohol intake, ethanol levels, urea levels, and creatinine levels were analyzed. ROC curve analysis was performed to evaluate the predictive power of ONSD to diagnose methanol intoxication. The area under the curve was 0.857 for the cut-off value of 5.05 mm (95 % CI: 0.728–0.985; p < 0.001), with a sensitivity of 80.8 % and a specificity of 100 %. In the regression analysis performed to determine the prognostic value of the parameters in estimating mortality in methanol intoxication cases, an increase in ONSD (OR: 3.619; 95 % CI: 0.057–0.199; p = 0.001), an increase in lactate levels (OR: 5.653; 95 % CI: 0.040–0.085; p < 0.001), and increased duration after alcohol intake (OR: 2558; 95 % CI: 0.004–0.034; p = 0.014) were identified as independent predictors of mortality, but pH, HCO 3 , and base deficit levels were not significant predictors. We believe that ONSD can be helpful for the differential diagnosis and prognosis of patients with suspected methanol toxicity who presented with alcohol intake. • As a result of our study, it was observed that ONSD increased in cases of methanol intoxication, but there was no increase in ONSD in patients who took ethyl alcohol. • ONSD can be used in the differential diagnosis of cases with suspected methanol intoxication due to alcohol intake. • We think that ONSD can be used to predict the prognosis of cases with suspected methanol intoxication and admitted due to alcohol consumption. [ABSTRACT FROM AUTHOR]