Extra-pseudocapsular Transnasal Transsphenoidal Resection of Pituitary Macroadenoma: Technique Note and Evaluation of Endocrine Function.

[OBJECTIVE] In this study, we investigated the surgical technique and endocrine assessment of pituitary function of patients with macroadenoma treated by extra-pseudocapsular transnasal transsphenoidal surgery (ETTS).

[METHODS] Clinical data of 144 patients with pituitary macroadenomas in the same surgical group at the Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology were retrospectively analyzed from January 2019 to June 2021. Based on the results of the endocrinological evaluation and MRI examinations before and after surgery, the fluctuation of pituitary function and the extent of resection were analyzed. Multiple Logistic regression analysis was used to determine the predictors affecting postoperative tumor residual.

[RESULTS] Among the 144 patients with pituitary macroadenomas, 72 (50.0%) were female and 72 (50.0%) were male, the median age was 50 years, 26 (18.1%) had invasiveness grade 0, 46 (31.9%) had grade I, 57 (39.6%) had grade II, and 15 (10.4%) had grade III according to Lu's classification method. Based on observation during surgery, 37 cases (25.7%) had no pseudocapsule, 54 cases (37.5%) had incomplete pseudocapsule, and 53 cases (36.8%) had intact pseudocapsule. In addition, 91 (63.2%) patients had total resection, 39 (27.1%) had subtotal resection, and 14 (9.7%) had partial resection. As for anterior pituitary function, 13 of 19 hypothyroid patients had recovery after surgery, with a remission rate of 68.4%. Eighteen of the 26 decreased cortisol patients got back to normal, with a remission rate of 69.2%. A total of 27 of 51 patients with hypogonadism improved, with a remission rate of 52.9%. Univariate and multivariate analyses indicated that gender, tumor size, and invasiveness were predictors of postoperative residual in patients (P<0.05).

[CONCLUSION] The results showed that ETTS is an effective treatment modality for restoring the function of pituitary gland of the patients with macroadenomas. Tumor size and invasiveness are predictors of the extent of surgical resection and postoperative residual of macroadenomas.