Shift of the Brain during Functional Neurosurgery.

Kim, Suk Min; Hwang, Hyung Sik; Salles, Antonio De

Original Article

Journal of Korean Neurosurgical Society 2005;38(5): 359-365.

Suk Min Kim, Hyung Sik Hwang, Antonio De Salles

¹Department of Neurosurgery, College of Medicine, Hallym University, Seoul, Korea. hyungsik99@yahoo.co.kr
²Division of Neurosurgery, University of California, Los Angeles, California, USA.

ABSTRACT

OBJECTIVE
The study investigates the extent of brain shift and its effect on the accuracy of the stereotaxic procedure.
METHODS
Thirty-five patients underwent 40stereotactic procedures between June 2002 and March 2004. There were 26 males, mean age 59years old. There were 34procedures for Parkinson's disease, 2 for essential tremor, 3 for cerebral palsy, 1 for dystonia. Patients were divided in four groups based on postoperative pneumocephalus: under 5cc (9 procedures), between 5~10cc (13procedures), between 10~15cc (11procedures) and more than 15cc (7procedures). The coordinates of the anterior commissure(AC), posterior commissure(PC), and target were defined in pre-and intraoperative magnetic resonance image scans and the amount of air volume was measured with @Target (BrainLab, Heimstetten, Germany). RESULTS: The mean AC-PC was 26.5mm for patients with less than 5cc, 26.9mm for 5~10cc, 25.8mm for 10~15cc and 26.2mm for more than 15cc. The length of AC-PC line and coordinates of AC, PC was also not statistically different, Euclidean distance as well as delta x, delta y, delta z of AC, PC, and target were also not statistically different among the groups (p<0.1). There was a variance in target of 0.7~7.6mm, Euclidean distance of 2.5mm, related to electrophysiology but not to brain-shift.
CONCLUSION
The amount of air accumulated in the intracranial space and compressing the cortical surface has no effect on the localization of subcortical stereotactic target and landmarks.