Perivascular Diffusivity Suggests Dynamic and Modifiable Glymphatic Transit in Idiopathic Intracranial Hypertension

Preliminary work suggests that glymphatic transit is abnormal and dynamic in idiopathic intracranial hypertension (IIH), although its incomplete characterization across the disease course has led to debate as to its pathophysiologic relevance. We seek to clarify whether glymphatic transit varies across IIH's disease course, correlates with intracranial pressure, and might be measured radiographically to aid diagnosis.

Diffusion tensor imaging along the perivascular space (ALPS) was used to measure perivascular diffusivity and generate indices of glymphatic transit (ALPS-indices). We studied healthy controls and participants with IIH cross-sectionally, the latter stratified into untreated, treated, or cured IIH. Participants with untreated IIH were substratified as "acute" if imaged