You know the triad for normal pressure hydrocephalus (NPH). Wet, wobbly, and wacky. And you have probably heard of the Evan’s index—the relative proportion of the lateral ventricles in reference to the inner table of the skull. But you might not have heard of high-convexity tight sulci. Now you have. Produced by James E. Siegler. Music courtesy of Jason Shaw, Javolenus, and Lee Rosevere, under a Creative Commons License. The opening theme was composed by Jimothy Dalton. Sound effects by Mike Koenig and Daniel Simion. BrainWaves' podcasts and online content are intended for medical education only and should not be used for clinical decision making. Be sure to follow us on Twitter @brainwavesaudio for the latest updates to the podcast. REFERENCES Kitagaki H, Mori E, Ishii K, Yamaji S, Hirono N and Imamura T. CSF spaces in idiopathic normal pressure hydrocephalus: morphology and volumetry. AJNR American journal of neuroradiology. 1998;19:1277-84. Sasaki M, Honda S, Yuasa T, Iwamura A, Shibata E and Ohba H. Narrow CSF space at high convexity and high midline areas in idiopathic normal pressure hydrocephalus detected by axial and coronal MRI. Neuroradiology. 2008;50:117-22. Allali G, Laidet M, Armand S, Momjian S, Marques B, Saj A and Assal F. A combined cognitive and gait quantification to identify normal pressure hydrocephalus from its mimics: The Geneva's protocol. Clinical neurology and neurosurgery. 2017;160:5-11. Graff-Radford J, Gunter JL, Jones DT, Przybelski SA, Schwarz CG, Huston J, 3rd, Lowe V, Elder BD, Machulda MM, Gunter NB, Petersen RC, Kantarci K, Vemuri P, Mielke MM, Knopman DS, Graff-Radford NR and Jack CR, Jr. Cerebrospinal fluid dynamics disorders: Relationship to Alzheimer biomarkers and cognition. Neurology. 2019;93:e2237-e2246.