Clinical characteristics and outcomes after shunt surgery in idiopathic normal pressure hydrocephalus with or without prior cerebrospinal fluid tap testing: a single-center follow-up study of 481 patients

This real-world study shows that a majority of iNPH patients can be routinely assessed by a clinical team and shunted with favorable outcomes without a supplementary predictive tap test. The worse outcomes seen in TT patients are likely to be due to higher prevalence of neurological comorbidity and delayed time to surgery. We suggest that the tap test may be reserved for difficult patients with suspected iNPH including those who present with concurrent other neurological disorders.