Reconstruction of the Intrasellar Tumor Resection Cavity Is Not Necessary to Prevent Optic Chiasm Prolapse Following Transsphenoidal Removal of Pituitary Macroadenomas

Introduction: Secondary empty sella syndrome associated with delayed visual deterioration has been reported following transsphenoidal resection of pituitary adenomas. To prevent postoperative herniation of the optic apparatus, reconstruction of the intrasellar tumor resection cavity with autologous tissues such as adipose tissue or muscle is commonly employed. Harvesting of such tissues may be complicated by cosmetic deformity, infection, or hematoma formation. In our practice, the resection cavity is not reconstructed, and we sought to determine the incidence of postoperative optic chiasm prolapse following removal of pituitary macroadenomas.

Methods: A retrospective review was performed for 100 consecutive patients with pituitary macroadenomas who underwent transsphenoidal resection with postoperative clinical and radiographic data greater than 6 months from the date of initial surgery. The position of the optic chiasm was determined on sagittal MRI and defined as the distance above a line constructed between the superior aspect of the tuberculum sellae and the dorsum sellae. The position of the optic chiasm was compared between the preoperative MRI and the available MRI most distant from the date of surgery. Visual data were obtained from the clinical record.

Results: All patients underwent endoscopic transsphenoidal resection of pathologically demonstrated pituitary adenomas without packing of the tumor resection cavity using synthetic or autologous materials. Preoperative MRI demonstrated the presence of a macroadenoma with suprasellar extension in all cases, with a mean tumor height dimension of 23.4 mm (SD 5.1). The average position of the optic chiasm preoperatively was 7.6 mm (SD 3.3) above the superior aspect of the sella turcica. The mean time between the date of surgery and postoperative MRI was 422 days (SD 239). No patient reported delayed visual deterioration postoperatively, and the mean position of the optic chiasm on postoperative MRI was 1.1 mm (SD 0.7). Despite the presence of a large intrasellar tumor resection cavity in all cases, inferior prolapse of the optic chiasm was observed on delayed postoperative MRI in only 1/100 cases and was not associated with visual impairment.

Conclusions: Reconstruction of the tumor resection cavity following transsphenoidal removal of pituitary adenomas, including macroadenomas, is not necessary to prevent optic apparatus prolapse and delayed visual deterioration.