Background: Surgical outcome prediction has assisted physicians in discussing surgical intervention or expectant management. While increasing pituitary tumor size would seem to be associated with increasing challenge of removal and associated complications, that relationship has not been borne in the literature.
Methods: We performed a retrospective review of a consecutive cohort of pituitary surgeries completed at our institution. Data included age at the time of surgery, presenting symptoms and Glasgow Coma scale (GCS), GCS at discharge or 7 days postoperatively, GCS at 6 months, adenoma size, imaging characteristics of the tumor and brain before resection, postoperative complications, the presence of preoperative hydrocephalus, brainstem compression, and patient mortality.
Results: Patients with giant adenomas were more likely to present with a cranial nerve palsy (P = 0.019), altered mental status (P = 0.0001), hydrocephalus (P = 0.002), and mass effect on the brainstem (P = 0.020). Patients who experienced a postoperative decline in mental status were more likely to present with altered mental (P = 0.006), had an increased prevalence of mass effect on the brainstem (P = 0.005), and were more likely to have either an ischemic stroke (P = 0.0001) and vasospasms or new intraparenchymal hemorrhage (P = 0.013).
Conclusion: The results of this study demonstrate that postoperative mental status declines after pituitary adenoma resection can be directly related to brainstem compression and further surgical irritation of the surrounding vasculature. The intraoperative irritation can be multifactorial and may result as the decompressed brain structures assume their anatomical position.
Keywords: Brainstem compression; Hydrocephalus; Pituitary tumors; Vasospasm.