gms | German Medical Science

Objective: Inaccurate ventricular catheter (VC) placement inherits multiple risks to its long term function and to the patient’s condition. According to earlier studies the free hand technique shows up to 40 percent improper positioning of VC. In order to facilitate an accurate and controlled placement of VCs a smartphone assisted guiding instrument was introduced. In the GAVCA Trial the guide is compared to the standard free-hand technique.

Method: The smartphone assisted guiding tool is applied by using a preoperative coronal section at the level of the anterior comissure in order to determine the insertion angle of the VC, which can be applied intraoperatively by using the guiding instrument. Primary results of 35 catheter placements in patients with an FOHR of 0.38 ± 0.05 revealed good applicability of the guide. In all cases a primary catheter placement was achieved, no catheter failure occurred in a mean follow up of 9.1 ± 5.3 months. In this context a multicenter prospective randomised trial is designed in order to verify the tool on a broad basis.

Results: The prospective multicenter GAVCA study is designed with two arms in which patients will be randomized to get either a free handed or a guided VC placement as long-term implant. Inclusion criteria are the frontal approach for the VC, an FOHR <0.5, and a newly used brain tissue insertion trajectory. The controlled study is implemented in January 2013, and will comprise 144 patients over an estimated time period of 24 months. The primary criterion of the study is the rate of accurate ipsilateral VC placement without significant tissue contact.

Conclusions: Due to first experience in a cohort study the use of the catheter guide seems to result in accurate VC placement even in narrow ventricles. In order to verify a higher precision of the guide compared to the standard freehand technique a multicenter prospective randomised trial is initiated.