Growth pattern of craniopharyngioma determined by the origin of tumor regarding diaphragma sellae and the competency of the aperture: Reappraisal in the era of endoscopic endonasal surgery

Background: Advances in the endoscopic endonasal approach (EEA) have increased the under-standing of craniopharyngioma anatomy. We have previously proposed a relationship among cranio-pharyngioma growth pattern, their origin relative to the diaphragm sellae, and their aperture compe-tency. To reappraise that relationship, we retrospectively reviewed the diaphragm sellae anatomy of patients who underwent EEA for craniopharyngioma. Materials and Methods: From May 2010 to January 2013, thirty five patients underwent EEA procedures for craniopharyngiomas. Twenty patients without a surgical history were included in the study, and medical records describing the spatial relations between the tumors and the diaphragma sellae were reviewed and correlated with the tumor growth patterns on preoperative images. Results: All of the tumors were completely removed. Three prechiasmatic tumors were located un-der intact diaphragma sellae. Six retrochiasmatic tumors were composed of supra- and subdiaphrag-matic components that were continuous through an incomplete aperture of the diaphragm. Eleven retrochiasmatic tumors were located above intact diaphragms. Visual symptoms were normalized or improved in twelve of the sixteen patients with preoperative visual deficits. Preoperative hypotha-lamic dysfunction was recovered in ten of twelve patients. Conclusions: The EEA revealed the detailed tumor anatomy and confirmed our previous hypoth-esis that craniopharyngioma growth patterns are principally determined by the origin of the tumor relative to the diaphragma sellae and by the aperture competency. The EEA is indicated for removing both prechiasmatic and retrochiasmatic craniopharyngiomas.