Normal Pressure Hydrocephalus: Very long term outcome after shunt surgery

¹ Johns Hopkins School of Public Health, United States
² Johns Hopkins Hospital, United States

^* To whom correspondence should be addressed. E-mail: dr{at}jhmi.edu.

Accepted 29 February 2008

	Abstract

Background/Objective: Little is known about the very long term clinical course and management of patients with Normal Pressure Hydrocephalus (NPH) treated by CSF shunting.

Methods: We retrospectively reviewed records of 55 patients diagnosed with INPH and treated with CSF shunts, all of whom were followed for more than 3 years after the original shunt surgery. At each annual follow-up visit, the patient was assessed by Folstein MMSE, detailed clinical evaluation of gait and assessment of headache, cognition, gait or urination as assessed by the patient and relatives

Results: The mean duration of follow-up was 5.9 ±2.5 years. There was an overall sustained improvement among all symptoms. Gait showed the highest maintenance of improvement over baseline (83% at 3 years and 87% at the last analyzed follow-up of 7 years) cognition showed intermediary improvement (84% and 86% respectively) and urinary incontinence showed the least (84% and 80% respectively). Fifty three percent of patients required shunt revisions. Indications for revision included shunt malfunction (87 %), infection (10%) and change of shunt configuration (3%). Overall, 74% revisions resulted in clinical improvement.

Conclusions: Clinical improvement of patients with NPH can be sustained for 5-7 years in some patients with NPH, even if shunt revision surgery is needed multiple times. With earlier diagnosis and treatment of NPH and the increasing life span of the aging population, the need for long-term follow-up after shunt surgery for NPH may be greater than in the past. Monitoring, identification and treatment of shunt obstruction is a key management principle.