Comparative Anatomical Study on Operability in Surgical Approaches to the Anterior Part of the Third Ventricle.

ABSTRACT

BACKGROUND: Surgery of the third ventricle still represents a challenge in modern neurosurgery. To optimize the surgical planning, some aspects, related to ventricular anatomy, have to be taken into consideration. An operability score could represent a preoperative tool to evaluate these variables to choose a tailored surgical approach. METHODS: We compared the transcallosal transforaminal approach and the combined interhemispheric subcommissural translamina terminalis approach (CISTA) to the anterior part of the third ventricle, applying the operability score. RESULTS: Compared with the transcallosal transforaminal approach, the CISTA provides a statistically significant improvement in terms of depth of surgical field, surgical angle of attack, and maneuverability arc considering as 4 approach-related critical structures the optic chiasm (P value <0.0001, <0.0001, <0.0001, respectively), the anterior commissure (P value <0.0001, <0.0001, <0.0001 respectively), the tuber cinereum (P value <0.0001, 0.0224, 0.0173), and the interthalamic adhesion (P value 0.2917, <0.0001, <0.0001 respectively). CONCLUSIONS: Tumors originating from the anterosuperior part of the third ventricle can be easily approached through a transcallosal transforaminal route, whereas lesions arising from the anteroinferior portion of the third ventricle might be safely and effectively approached through the CISTA.