• Written By: Howard Pomeranz, MD, PhD

    In this excellent paper, the authors suggest updated diagnostic criteria for what they term pseudotumor cerebri syndrome (PTCS), incorporating typical neuroimaging abnormalities, clarification of normal opening pressure in children and features distinguishing intracranial hypertension without papilledema from intracranial hypertension with papilledema. They note that it may be primary (idiopathic intracranial hypertension) or arise from an identifiable secondary cause.

    Their objective is to provide accurate parameters for reliably diagnosing patients in order to identify them promptly at presentation and obtain the necessary diagnostic testing and treatment to avoid or minimize visual loss.

    They propose the following diagnostic criteria for PTCS: (1) papilledema, (2) normal neurological exam except for cranial nerve abnormalities, (3) neuroimaging criteria of normal brain parenchyma without evidence of hydrocephalus, mass or structural lesion and no abnormal meningeal enhancement on MRI, (4) normal cerebrospinal fluid (CSF) composition, and (5) elevated lumbar puncture opening pressure, defined as greater than or equal to 250 mm in adults and greater than or equal to 280 mm in children in a properly performed lumbar puncture.

    They note that with these revised criteria, documentation of an elevated CSF opening pressure is required for the diagnosis of definite PTCS, but diagnosis of probable PTCS may still be made in an otherwise typical patient if bilateral papilledema is present and the measured opening pressure is not elevated.

    If papilledema is not present, then the combination of an elevated CSF pressure and a sixth nerve palsy can be used to make the diagnosis of PTCS. Without papilledema or a sixth nerve palsy, a combination of an elevated CSF pressure and the presence of three of four radiologic criteria can only suggest the diagnosis. Notably, lumbar puncture is always required in the workup of a patient considered to have PTCS.

    An accompanying editorial reviews and clarifies the article’s proposed new criteria for PTCS.