Incidence of Diplopia Secondary to Cranial Neuropathies after Endoscopic Endonasal Pituitary and Transcavernous Surgery

Document Type

Conference Proceeding

Publication Date


Publication Title

J Neurol Surg B Skull Base


Background: Resection of cavernoinvasive pituitary tumors has been a longstanding topic of controversy due to the risks of surgery within the cavernous sinus. Recent advances in surgical anatomy and techniques have paved the way for endoscopic transcavernous surgery (TCS) to address pathology in this region.

Objective: We aim to elucidate the rates of diplopia secondary to cranial neuropathy after endoscopic endonasal skull base approaches for pituitary tumor surgery.

Methods: A prospectively collected and retrospective cohort analysis of 248 consecutive surgeries for pituitary tumor via an endoscopic endonasal approach between 2018 and 2022.

Results: The median age was 49 years old: 56% women, 128 functional (52%) and 49 residual/recurrent tumors (20%). Pituitary surgery without cavernous access was performed in 132 patients, while 116 patients (47%) underwent 132 TCS (16 patients with bilateral approaches). TCS was utilized on 60% of patients with functional adenomas compared with 33% of patients with non-secreting tumors (p < 0.01). A total of 17 patients (7%) developed diplopia: 4 CN III, 10 CN VI, and 3 had both CN III and VI palsies. Diplopia was more common after TCS compared with routine transsellar pituitary surgery, 11% versus 1.5% (OR: 8.33, 95% CI: 1.87–37.21; p < 0.01). Patients with bilateral cavernous sinus surgery had an increased risk for cranial neuropathy, 45% versus 11% (OR: 4.09, 95% CI: 1.18–14.18, p < 0.05). Patients with residual/recurrent disease were more likely to undergo at least one-sided TCS compared with first time surgery patients (76 vs. 40%, p < 0.01), repeat surgery did not confer an increased risk of diplopia compared with first time TCS (OR: 1.68, 95% CI: 0.57–4.98, p = 0.34). Isolated medial wall resection (n = 48) carried a 2% risk of diplopia compared with 16%, 18%, and 22% for surgery in the superior (n = 55), posterior (n = 60), and inferior (n = 45) compartments of the cavernous sinus, respectively; meanwhile, lateral compartment surgery (n = 12) had a 33% risk of diplopia. All patients with CN III palsy had surgery within the superior compartment. Cessation of diplopia and return of normal extraocular movements occurred at a rate of 18, 45, 82, and 100% at 2 weeks, 3 months, 4 months, and 6 months postoperatively, respectively. The gross total resection rate for this series is 85% with a remission rate of 88% for functional tumors. There was no incidence of carotid artery injury or stroke.

Conclusion: Pituitary surgery carries a risk for ocular dysmotility and diplopia which is increased when extended into the cavernous sinus; isolated medial wall resection, however, does not exhibit a significantly increased risk profile compared with routine transsellar pituitary surgery. Bilateral TCS carries a heightened risk profile, likely due to increased packing needed to obliterate the remaining venous channels. All patients in our series, however, made a complete recovery without long-term sequelae, making TCS safe and effective for the treatment of cavernoinvasive pituitary pathology. These outcomes, along with the high resection and remission rates, supports the benefit of TCS for invasive and functional adenomas.