Transsulcal parafascicular brain path-assisted approach to subcortical lesions: 2-dimensional operative video

BACKGROUND: Approaches to subcortical lesions have traditionally been limited by the morbidity of white matter dissection and fixed blade retraction required to reach these targets. Visualization of deep surgical fields with a traditional operating microscope is also poor. Coordinated use of intra-operative image guidance, a tubular retractor (BrainPath(®), Nico Corp, Indianapolis, Indiana), a high-definition exoscope (Vitom(®), Karl Storz Endoscopy America, Inc, El Segundo, California), and a low-profile resection device (Myriad(®), Nico Corp) facilitates atraumatic access to and resection of subcortical lesions including primary brain tumors, brain metastases, and intracerebral hemorrhages.[1] Use of pre-planned transsulcal and parafascicular trajectories based on magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) can further mitigate damage to white matter tracts with this technique. CASE DESCRIPTION: We herein present details of the transsulcal parafascicular BrainPath(®)-assisted approach to subcortical lesions and demonstrate the utility of this technique using two patient examples: a spontaneous deep left posterior temporal lobe hematoma in a 41-year-old male and a left hippocampal glioblastoma in a 54-year-old female. Key steps include selection of appropriate patients with non-skull base subcortical lesions, preoperative trajectory and tube depth planning based on MRI (including diffusion-weighted imaging and DTI), patient positioning and operating room setup to facilitate pre-planned trajectories and surgeon ergonomics, and use of low-profile instruments with a two-handed surgical technique. CONCLUSION: Given recent data demonstrating the utility of this approach for hematoma evacuation and a likely increased future usage of this technique,[2] surgeon familiarity with the above steps will be of increasing importance.