Infra-Occipital Supra-Tentorial Approach for Resection of Low-Grade Tumor of the Left Lingual Gyrus: 2-Dimensional Operative Video.

ABSTRACT

Surgical treatment of lesions involving the postero-medial occipito-temporal region is challenging because of high risk of morbidity due to damage or excessive retraction of critical neuro-vascular structures, especially within the dominant hemisphere.1-3 Here, we describe the case of a 17-yr-old patient who underwent resection of an epileptogenic low-grade tumor located within the left-dominant lingual gyrus. Seizures were characterized, as a first symptom, by right-sided simple visual hallucination that pointed to the left pericalcarine region, corresponding to the lesion location. No signs of primary involvement of anterior temporo-mesial structures (hippocampus/amygdala) were found. As the anatomo-electroclinical correlation was concordant, direct tumor removal was indicated through an infra-occipital supratentorial approach. This route allowed direct access to the target through a safe extra-axial corridor, which limits intraparenchymal dissection until the tumor margin is identified and avoids critical vascular structures, such as the vein of Labbé.4,5 An external cerebrospinal fluid (CSF) drainage was used to facilitate brain relaxation, minimizing brain and venous retraction and, consequently, reducing the risk of postoperative neurological complications, especially for vision. Postoperative magnetic resonance imaging (MRI) demonstrated no surgical complications. Pathological examination revealed a ganglioglioma. At 9-mo follow-up, the neurological examination was normal, antiepileptic therapy was stopped, and the patient was seizure-free. The video describes the main surgical steps, using both intraoperative videos and advanced 3-dimensional modeling of neuroimaging pictures. Informed consent was obtained for surgery and video recording.