Transcondylar Fossa Approach for Cerebellopontine Angle and Ventral Brainstem Lesions: Microsurgical Experiences and Avoidance of Complications

To treat the large tumors located in cerebellopontine angle (CPA) and vascular pathologies including aneurysms and dissection located around the ventral brainstem, transcondylar fossa approach (TCFA) has been regarded as less invasive one. Overall 10 patients had large tumors (D> 3 cm) including schwannomas (n = 8) and meningiomas (n = 2) located in the CPA and 17 patients had vascular pathologies including vertebra-basilar artery aneurysms (n = 14) and dissection (n = 3). Anatomical aspects of the condylar fossa, occipital condyle, and adjacent neurovascular structures were evaluated preoperatively and postoperatively using a three-dimensional computed tomography and magnetic resonance imaging. Gross-total removals in tumor patients achieved without resection of the occipital condyle. In 10 patients with saccular aneurysms, the aneurysms were clipped without resection of the occipital condyle and in 4 patients, partial resection of the condyle and jugular tubercle was necessary to obtain proximal control of the vertebral artery. We met two cases with vertebral artery injury and one case with postoperative cerebrospinal fluid. Transcondylar fossa approach was less invasive technique with minimal or no resection of the occipital condyle comparing with other approaches to ventral brainstem. To avoid complications, anatomical knowledge on the joint and the condylar veins should be reviewed.