Investigating shunt function using continuous intracranial pressure monitoring in adults: single center experience

OBJECT Managing symptomatic ventriculoperitoneal shunts with no clear evidence of shunt malfunction either clinically or radiologically can be a difficult task. The aim of this study was to assess intracranial pressure (ICP) monitoring as a method of investigating shunt function. METHODS The authors performed a retrospective analysis of 38 continuous ICP monitoring procedures done in patients with ventriculoperitoneal shunts and suspected shunt malfunction. RESULTS Thirty-eight procedures were performed in 31 patients between January 2005 and October 2008. Sixteen recordings were normal, 6 revealed overdrainage or low pressure, 11 indicated underdrainage or high pressure, and 5 showed variable shunt function. Based on the findings after 20 procedures (53%), patients were treated conservatively: 4 by readjusting the valve setting and 16 by referral to the headache neurologist for medical treatment. Forty-five percent of the conservatively treated patients improved. Surgical exploration was undertaken following 18 procedures (47%); 72% of the surgically treated patients improved. CONCLUSIONS Continuous ICP monitoring using an intraparenchymal probe is a safe and effective method of investigating adult hydrocephalus.