gms | German Medical Science

Objective: Hydrocephalus can be caused by obstruction leading to restricted liquor flow or by an imbalance of absorption and production of cerebrospinal fluid. The aim of this study is to investigate the demographic characteristics of adult patients with hydrocephalus, the influence of age, sex, pathogenesis, and type of implants on rate, causes and time of revision

Methods: A retrospective analysis of medical charts, operative reports, and clinical follow-up visits of 158 patients with hydrocephalus treated in our department between 2018 and 2021 was conducted. Demographic parameters, type of underlying disease, type of catheters and valves, and number and reason for revision surgery were evaluated. Statistical analysis was performed using Kruskal-Wallis-test. P-values

Results: The median age of this study cohort was 62.5 years (IQR 25-75: 51-73 years; 89 female, 69 male). The most common indications for initial shunt surgery were posthemorrhagic hydrocephalus (36.7%) and normal pressure hydrocephalus (NPH) with 20.9%. The two used valve systems were programmable differential pressure valves with (10.8%) and without an additional gravitational unit (89.2%). 16% of patients (n=25) required revision surgery. Most common causes of 41 revision surgeries were misplacement of parts of the shunt system with 28.0 % and mechanic dysfunction with 29.3 %. An infection of shunt system leading to revision surgery was seen in only one patient (4%).

The rate of revision was associated with the type of valve and the etiology of hydrocephalus. Overall, the mean number of revisions per year was 0.24±0.72. Patients with additional gravitational units had a significant higher number of revisions per year (mean 0.82±1.35) than without an additional gravitational unit (mean 0.17±0.57) (p<0.001). Hydrocephalus caused by tumor was also associated with higher revision rates (mean 0.61±1.13/year) vs. NPH (mean 0.20±0.76/year; p=0.013) vs. posthemorrhagic hydrocephalus (mean 0.18±0.72/year; p=0.015).

Furthermore, the median time from initial shunt surgery to revision was 26 days (IQR25-75: 9-64 days). Etiology of hydrocephalus, used valve systems and cause of revision showed no significant influence on the distance of time.

Conclusion: In our study group a higher number of revisions was seen in patients with hydrocephalus caused by tumors and differential pressure valves with additional gravitational unit. These results yield to identify more risk factors to minimize complications and revision surgeries.