Measures of cognition and gait pre- and post-lumbar puncture (LP) may predict which patients with concern for normal pressure hydrocephalus (NPH) are better candidates for ventriculoperitoneal shunt (VPS).
In NPH, identifying patients’ response to high volume LP and candidacy for VPS is challenging. The NPH Protocol at Vanderbilt University Medical Center collects pre- and post-LP data on cognitive tests and physical therapy (PT) assessments on patients with suspicion for NPH. All patients are subsequently evaluated by neurosurgery to assess for post-LP response.
All patients who completed the NPH Protocol between 02/2022-12/2023 were included. The NPH Protocol consists of a pre-LP neuropsychological testing, PT evaluation (pre- and post-LP), >30 cc cerebrospinal fluid (CSF) tap, and subsequent neurosurgical consultation. Patients were dichotomized into two groups, those who received VPS and those who did not. A variety of demographic, cognitive, and physical therapy outcomes were compared between the two groups (i.e., VPS vs. no VPS).
Of the 54 patients who completed the NPH Protocol (age: 70.7±8.1, 57.4% female), 22 ultimately had a VPS implanted (40.7%). Montreal Cognitive Assessment (MoCA) total scores were not different between the two groups pre-LP or post-LP, nor was the change in MoCA score (p-values>.05). Regarding the Timed Up & Go test, those ultimately shunted were slower pre-LP (27.7±15.3 seconds vs. 18.4±11.1 seconds, p=.02), and they improved more than those who did not receive VPS (6.3±4.2 second improvement vs. 1.6±7.7 second improvement, p=.03). Those who received VPS were also more impaired on the Gait Scale for NPH pre- and post-LP (p-values=.02 and .03, respectively).
In the NPH Protocol, the Timed Up & Go and Gait Scale for NPH scores distinguished patients who were shunted versus not shunted, though MoCA did not. These specific measures may predict candidates for shunt in NPH.