• Mohamed Macki, Abhimanyu Mahajan, Rhonna Shatz, Ellen L Air, Marina Novikova, Mohamed Fakih, Jaafar Elmenini, Manpreet Kaur, Kenneth R Bouchard, Brent A Funk, and Jason M Schwalb.
• Department of Neurosurgery, Henry Ford Hospital, Detroit, Michigan.
• Neurosurgery. 2020 Oct 15; 87 (5): 999-1007.

BackgroundFollowing Bayes theorem, ventriculomegaly and ataxia confer only a 30% chance of idiopathic Normal Pressure Hydrocephalus (NPH). When coupled with positive responses to best diagnostic testing (extended lumbar drainage), 70% of patients recommended for shunting will not actually have NPH. This is inadequate clinical care.ObjectiveTo determine the proportion of alternative and treatable diagnoses in patients referred to a multidisciplinary NPH clinic.MethodsPatients without previously diagnosed NPH were queried from prospectively collected data. At least 1 neurosurgeon, cognitive neurologist, and neuropsychologist jointly formulated best treatment plans.ResultsOf 328 total patients, 45% had an alternative diagnosis; 11% of all patients improved with treatment of an alternative diagnosis. Of 87 patients with treatable conditions, the highest frequency of pathologies included sleep disorders, and cervical stenosis, followed by Parkinson disease. Anti-cholinergic burden was a contributor for multiple patients. Of 142 patients undergoing lumbar puncture, 71% had positive responses and referred to surgery. Compared to NPH patients, mimickers were statistically significantly older with lower Montreal Cognitive Assessment (MoCA) score and worse gait parameters. Overall, 26% of the original patients underwent shunting. Pre-post testing revealed a statistically significant improved MoCA score and gait parameters in those patients who underwent surgery with follow-up.ConclusionBecause the Multidisciplinary NPH Clinic selected only 26% for surgery (corroborating 30% in Bayes theorem), an overwhelming majority of patients with suspected NPH will harbor alternative diagnoses. Identification of contributing/confounding conditions will support the meticulous work-up necessary to appropriately manage patients without NPH while optimizing clinical responses to shunting in correctly diagnosed patients.Copyright © 2020 by the Congress of Neurological Surgeons.

24 keywords...

hide…