Neuronavigation-assisted trajectory planning for deep brain biopsy with susceptibility-weighted imaging

Susceptibility-weighted imaging (SWI) exploits susceptibility differences between tissues to enhance contrast in magnetic resonance imaging to enable the visualization of small blood vessels that are difficult to detect by other contrast agents. This study explored the value of SWI-based planning for neuronavigation-guided deep brain biopsies to reduce the incidence of post-surgical complications.

The cohort of 84 patients was divided into 41 biopsies performed aided by SWI (SWI group) and 43 biopsies based on conventional T1w-Gd-based imaging (T1w-Gd group). Biopsy targets were determined using magnetic resonance spectroscopy (MRS) before the operation, and the safest trajectory was selected based on preoperative images of blood vessels.

Within 24 h of surgery, there was no radiographically identified bleeding, no blood extravasation and no clinical intracranial hypertension in the SWI group. Only one patient (2.5 %) with basal ganglia lymphoma developed transient hemiparesis after biopsy, who later recovered after undergoing symptomatic treatment. Complication rates in the SWI group were lower than in the T1w-Gd group, where a 7 % morbidity rate was encountered with one patient developing a permanent neurological deficit and two showing biopsy-associated hemorrhages. SWI imaging yielded a better visualization of subcortical vessels and deep-seated brain structures.

SWI-based imaging revealed significantly better visualization of small-caliber vasculature that was not detectable on conventional T1w-Gd imaging, minimizing damage to the brain and reducing postoperative complications. Furthermore, MRS can contribute significantly to target selection to improve the yield of image-guided biopsies.