Accuracy of a new MRI-based patient-individual stereotactic brain biopsy device in the dog
Presentation held at Forum American College of Veterinary Internal Medicine 2018, June 13-16, 2018, Seattle, Washington
Accuracy of a novel magnetic resonance imaging-based patient-individual stereotactic brain biopsy device in the dog
Genauigkeit einer Magnetresonanzthomographie basierten patientenspezifischen stereotaktischen Hirnbiopsie-Vorrichtung bei Hunden
The aim of the study was to determine the precision of the novel MRI-based patient-individual stereotactic brain biopsy device in dogs. Twenty-two canine cadavers with 2 target points each were used to determine accuracy. First, specific bone anchors and MRI-markers were secured to canine cadaver heads. Afterwards CT and MRI examinations of the heads were performed. Two target points and corresponding trajectories were defined on each MRI: left caudate nucleus and right piriform lobe. Based on MR-images, patient-individual frames including rigid needle placement ports to reach defined target points were constructed and printed with a 3D-printer. The needle was to enter the brain in a gyrus and not to penetrate the ventricles. The frames were secured to the bone anchors. Minimal-invasive access to the brain was created using a tool guide. The biopsy needle was placed through the needle placement port up to the predetermined depth. Afterwards CT examinations of the heads with biopsy needles placed in each target point were performed. Needle placement error was determined after fusion of MRI and CT examinations. Error was defined as deviation in mm between needle tip and anticipated target points. The total median needle placement error for all 42 target points was 0.84 mm (range: 0.09-2.76; outlier: 4.11). The median needle placement error for the caudate nucleus only was 0.67 mm (range: 0.09-1.25) and for the piriform lobe 0.85 mm (range: 0.14-2.76). Therefore, the MRI-based patient-individual stereotactic brain biopsy device reaches higher accuracy than most other described brain biopsy systems.