Optic Nerve Sonography to Monitor Treatment Efficacy in Idiopathic Intracranial Hypertension: A Case Report

Abstract

To report values of optic nerve sheath diameter (ONSD) and optic disc elevation (ODE) obtained with optic nerve sonography (US) in the diagnosis and monitoring of treatment efficacy in an adult with idiopathic intracranial hypertension (IIH). Serial measurements of the ONSD and ODE using B mode US were performed in a 45-years-old woman with IIH before and during after treatment with acetazolamide and diet. At first evaluation US showed a significantly enlarged ONSD (.68 cm right; .66 cm left side) and the presence of increased ODE (.1 cm right; .15 cm left side). Post-punctural assessments showed a bilateral decrease of ONSD (.58 cm right; .58 cm left side), without changes in ODE values. After 12 months of treatment with acetazolamide and diet ODE completely normalized (0 cm on both sides). ODE values correlated directly with ONSD, and both ODE and ONSD values correlated directly with BMI. Correlations were statistically significant. ONSD changes occurred rapidly after the lumbar puncture, whereas the papilloedema required longer to reduce. US of ONSD and ODE was useful to support the diagnosis of IIH and to monitor the efficacy of diet and pharmacological treatment. Further studies are required to evaluate whether this promising technique may be considered a reliable and accurate method to longitudinally evaluate patients with increased ICP secondary to IIH.