Tailored Callosotomy Guided by Neuronavigated Autofocus Microscope for Interhemispheric Transcallosal Approach to Intraventricular Lesions.

Abstract

The interhemispheric transcallosal route (IHTCR) is often chosen to approach intraventricular lesions, despite being associated with specific morbidity, such as disconnection syndrome; thus, some key points include minimizing the size of callosotomy and possibly avoiding the incision of the middle/posterior third of the body of the corpus callosum that might be associated with severe morbidity. Despite this need, reports on the use of neuronavigation for a tailored IHTCR are scarce in the literature. This study describes the technical nuances of our neuronavigated autofocus microscope (NAM)-guided strategy and reports our results about the size of the callosotomy. We retrospectively reviewed data from eight consecutive patients who recently underwent resection of intraventricular lesions via the IHTCR, guided by a NAM, at our institute from May 2024 to March 2025. We report detailed technical notes on the surgical planning and intraoperative neuronavigated images. In all patients the callosal section was located in the anterior third of the body of the corpus callosum. Callosotomy was smaller than 8 mm in six patients with small lesions and smaller than 20 mm in two patients with large lesions. In almost all cases, the size of the callosotomy was smaller than one half of the main diameter of the tumor. At follow-up, all patients experienced improvement in preoperative symptoms, and none showed signs of disconnection syndrome. Our NAM-guided strategy to a tailored IHTRC enables us to design a customized approach for the single patient, facilitating surgical procedures and achieving a small callosotomy size in relation to the dimensions of the tumor.