gms | German Medical Science

Objective: Cerebrospinal fluid (CSF) shunt failure in pediatrics is related to additional severe morbidity, an increase of procedures, radiation exposure and duration of hospital stay. Misplacement of ventricular catheters up to 40% using the freehand technique is considered as one major risk factor for shunt failure. Goal of the present study was to analyze catheter positioning and outcome in children using real-time ultrasound guidance for ventricular catheter placement.

Method: All patients <18 years who underwent ultrasound guided placement of ventricular catheters between April 2012 and March 2013 were analyzed subsequently. Technically, a burr hole probe or a convex probe via the fontanelle was used (ProSound Alpha 6, Hitachi Aloka Medical Ltd., Tokyo, Japan). A historical control group treated with freehand technique was matched. Patient charts were reviewed for age at surgery, etiology of hydrocephalus, duration of surgery, valve type and shunt survival. Frontal and occipital horn ratio (FOHR) was assessed. Catheter position was graded radiologically as either grade I (optimal), II (contralateral ventricle or contact with ventricular wall/choroid plexus) or III (misplacement). Correlation analysis was performed to identify determinants of outcome.

Results: The study group (n = 17) was balanced with the control group (n = 14) regarding relevant variables. Mean age was 4.7 years (range 0 to 15 years) versus 4.3 years (range 0 to 17 years) and preoperative FOHR was 0.45 (range 0.34 to 0.71) versus 0.43 (range 0.29 to 0.66). Major indication for surgery was posthemorrhagic hydrocephalus. In the study group, a grade I catheter position was achieved in 6 patients (35%) and a grade II in 11 patients (65%), compared to 2 (18%) and 3 patients (27%) in the control group, respectively. While no grade III position occurred in the study group, misplacement was found in 9 control patients (43%) (P=0.0029). Duration of surgery was similar (51 versus 49 minutes). Concerning outcome, we demonstrated a reduction in shunt failure rate by ultrasound guided placement, as failure rate was highest in grade III (83%) compared to grade I catheters (50%).

Conclusions: The present analysis demonstrated that real-time ultrasound guided placement of ventricular catheters showed a significant improvement of catheter positioning. As a result, we conclude that ultrasound catheter guidance offers a clinical relevant advantage without limitations and therefore should be favored over freehand technique.