Idiopathic intracranial hypertension or pseudotumour cerebri? The conundrum of nomenclature in the presence of normal cerebrospinal fluid pressures

Abstract

Idiopathic Intracranial Hypertension (IIH), also known as Pseudo tumour cerebri (PTC), is a condition in which the patient presents with signs and symptoms of increased intracranial pressure, with no demonstrable organic cause in the brain imaging including venous sinus thrombosis, and with normal cerebrospinal fluid (CSF) composition. Atypical cases of IIH have been reported periodically, and an important subset of these patients have normal CSF Opening pressure (OP) on lumbar puncture (LP). Application of strict criteria for diagnosing such patients needs reconsideration. We present 7 cases of IIH with normal CSF Opening pressures, out of 30 consecutive patients of suspected IIH admitted to the neurosurgery ward of a tertiary care hospital over a period of 2 years, kindling interest in nomenclature and diagnostic dilemma if strict criteria are adhered to. Keywords: Idiopathic intracranial hypertension (IIH), Pseudo tumour cerebri (PTC), Opening pressure, Lumbar puncture, Normal CSF pressures.