Ventriculoperitoneal shunt outcomes in neurodegenerative normal pressure hydrocephalus: A case series of 29 patients.

Background: Management of normal pressure hydrocephalus (NPH) can be complicated by the progression of underlying neurological conditions such as Alzheimer's disease or Parkinson's disease. The purpose of this study is to explore the long-term shunting response on gait dysfunction in patients with neurodegenerative NPH, a subtype of NPH occurring in patients with another neurodegenerative condition, as the duration of symptomatic improvement with shunting is unclear in this population. Methods: A retrospective chart review of patients undergoing evaluation for NPH at the Adult Hydrocephalus Center at Allegheny General Hospital was performed. Timed performances on two gait measures, the timed walk and timed up and go, were collected during a 2-day outpatient lumbar tap trial and on follow-up evaluation after shunt placement. Improvements over baseline were calculated at each follow-up and analyzed by years after shunt surgery. Potential sequelae of VPS such as subdural hematomas and infection during the study period were tallied. Results: Patients experienced statistically and clinically significant gait improvements within the first 6 months after surgery. Significant reductions in gait times were not found by the end of the 1st year after surgery through the remainder of the study period. Conclusion: While VPS can provide a limited period of improved gait, it was not shown that shunting can provide persisting benefit in patients with underlying progressive neurodegenerative disease. Shunting to alleviate gait symptoms should be considered on a case-by-case basis with patients and their families in alignment with care goals.