Mechanical Complications of Sophysa SM8 Shunt in Adult Hydrocephalus: A Monocentric Experience.

BACKGROUND

Sophysa SM8 is widely used by neurosurgeons in France. Published studies report shunt malfunction rates in adults between 18% and 29%. However, these studies included multiple valve types and thus entailed a serious confounding factor.

OBJECTIVE

To ascertain the incidence the Sophysa SM8 cerebrospinal fluid (CSF) shunt malfunctions in adults.

METHODS

We present a retrospective series of adult patients who underwent CSF shunt placement between 2000 and 2013 with Sophysa SM8.

RESULTS

In total, 599 patients (329 males and 270 females) were included. The mean age at surgery was 64.15 years (19-90) (SD 16.17; median 68.0). The causes of hydrocephalus were normal pressure hydrocephalus (49%), traumatic hemorrhages (26.5%), tumors (15.7%), cerebral aqueduct stenoses (3%), and arachnoid cysts (2%). The mean follow-up was 3.9 years (0-16) (SD 4.10; median 3 years). The rate of complications was 22.04% (132 of 599). Most frequent causes of complications were disconnection (25%), migration (12.9%), overdrainage (9.1%), and proximal obstruction (6.8%). In 17 cases (12.9%), no failure was diagnosed during revision. Seven infections (5.3%) were reported. The mean delay for the first revision was 1.70 years (0-13.93) (SD 2.67, median 0.35). The risk of shunt failure was 36% at 10 years. Seventeen percent of revisions occurred during the first year after shunt placement.

CONCLUSION

Disconnections are a very frequent complication of Sophysa SM8 valve. They are related to the 2-connector system of this valve. Based on these results, we recommend using 1-piece valves.