Postoperative Complications in Pituitary Adenomas: A Retrospective Risk Factors Analysis

Objective: Over the years, pituitary surgery has constantly evolved to prevent intra- and postoperative complications. However, postoperative cerebrospinal fluid (CSF) leak rates are still considerable, ranging from 1.4 to 16.9%, as reported in literature. Furthermore, endocrinological complications may affect pituitary surgery, as hypopituitarism, central adrenal insufficiency and diabetes insipidus, which incidence in literature is highly variable. Previous studies identified BMI >30, previous radiotherapy, adenoma size and type, intraoperative CSF leak and age younger than 50 years as potential risk factors for postoperative complications.

The aim of the study was to analyze the association between major surgical complications and patients characteristics, previous pituitary surgery, adenoma features, radiological invasiveness/extension and type of sellar reconstruction in a single-institution series of patients who underwent pituitary adenoma removal.

Methods: The medical charts of 85 patients who underwent endoscopic endonasal transsphenoidal pituitary adenoma removal between 2012 and 2018 were retrospectively evaluated. Three patients were excluded from the study, due to lack of clinical information. In case of intraoperative CSF leak, sellar reconstruction was performed with fascia lata. Knosp grading and Hardy’s classification were evaluated on preoperative MRI for macroadenomas. For the statistical analysis of correlation between postoperative complications and preoperative features Chi-squared and Wilcoxon’s sum-rank tests were conducted.

Results: Eighty-two patients were included in the study, 53 females (64.6%) and 29 males (35.4%); 63.4% of the tumors were macroadenomas. Median age at intervention was 50 years. Postoperative CSF leak rate was 8.5%. One patient developed massive pneumocephalus and meningitis after surgical repair of the leak; another patient suffered from postoperative meningoencephalitis. No visual loss or hemorrhagic complications occurred. A statistically significant association was found between postoperative CSF leak and previous transsphenoidal endoscopic surgery (p = 0.0064), Knosp grade 3 and 4 tumors (p = 0.0079), Hardy grade ≥ D adenomas (p = 0.0006) and Hardy sellar invasion (p = 0.0144).

Eighteen patients (22.0%) developed postoperative transient diabetes insipidus, 13 (15.9%) hypoadrenalism and 3 patients (3.7%) panhypopituitarism. Major endocrinological complications were significantly correlated with Hardy sellar invasion (p = 0.0088).

Conclusion: We identified history of previous transsphenoidal pituitary surgery, Knosp grade 3 and 4, Hardy grade D and E and Hardy sellar invasion as factors correlated to higher risk of postoperative CSF leaks and endocrinological complications. Based on these results, a patient-tailored sellar reconstruction and postoperative surveillance are recommended.