December 4, 2025

@michaelokun

A fantastic comprehensive review article w/ everything you need to know about Idiopathic Normal-Pressure Hydrocephalus just dropped in the NEJM. Hydrocephalus refers to a condition where cerebrospinal fluid accumulates excessively in the brain’s ventricles, resulting in enlarged chambers that contribute to disrupting walking, cognition and bladder control. Johnson and Williams describe in their new NEJM paper that idiopathic normal-pressure hydrocephalus is a common, frequently missed and potentially reversible neurologic condition in older adults. Key Points: -Idiopathic normal-pressure hydrocephalus presents w/ a triad of gait and balance changes, urinary urgency and cognitive slowing, however each feature has an extensive differential diagnosis on its own. - Prognostic testing w/ cerebrospinal fluid drainage or infusion methods improves selection of candidates who are likely to benefit from shunt surgery. - Programmable cerebrospinal fluid shunt systems remain the most effective treatment. My take: Nailing the diagnosis is so important in iNPH, and it is frequently a tricky endeavor for even an experienced clinician. One thing I would add to this article is that a fair number of folks with 'big ventricles' actually have Parkinson's disease, so don't forget considering the possibility of a levodopa trial in select persons who present for shunting. Here are 5 points that resonated w/ me: 1- Recognizing the gait pattern is essential because a wide-based slow shuffling walk frequently precedes memory or bladder issues and can be the earliest clue. 2- Imaging matters ,however it is not enough since enlarged ventricles alone do not confirm the diagnosis and this finding needs to be paired w/ symptoms and w/ testing. 3- A large-volume lumbar puncture can help by temporarily improving walking, which usually signals a higher likelihood of responding to a shunt. 4- Shunt surgery can meaningfully improve daily function, especially the gait and fall risk. Importantly, it should be performed at experienced centers using adjustable valves. 5- Delays in diagnosis affect outcome. #michaelokun #fixelinstitute #nph #parkinson