Outcomes of Visual and Oculomotor Function in Patients with Pituitary Adenomas after Endoscopic Endonasal Surgery

Background: Visual disturbances are a most common symptom of pituitary tumors due to their compression on the optic apparatus. But it could be associated with oculomotor disorder in case of tumor spreading into parasellar region causing from an oculomotor nerve impairment up to palsy.

Objective: To assay changes of visual functions in patients undergoing pituitary adenomas removal via endonasal endoscopic approach (EEA).

Material and Methods: A retrospective review of patient’s medical records with pituitary adenomas received surgical treatment in the department of neurological surgery “Interregional Clinical Diagnostic Center” (Kazan Medical State University) in the period between October 2009 and June 2018. All patients underwent pre- and postoperative neuroophthalmological examination.

Results: Among 479 patients a total 302 of them satisfied including criteria. All 302 had a chiasmal syndrome as an initial symptom or in combination with other symptoms at disease manifestation. And 28 patients in addition had different eye movement impairment.

There were 119 males and 183 females. Patient’s age was between 18 and 87 years (mean – 53.54 ± 1.46 years). According to tumor extension 258 (85.43%) patients had a suprasellar extension when the rest 44 (14.57) patients had a chasm compression.

All procedures were purely endoscopic. Due to extent of resection in 141 (46.68%) cases a gross-total resection (GTR) was achieved. Near-total (NTR) and subtotal resection (STR) was achieved in 62 (20.52%) and 63 (20.86%) cases, respectively, and partial resection in 36 (11.92%) cases. Following surgery an improvement of chiasmal syndrome was marked in 267 (88.41%) patients, no changes in 23 (7.61%) patients and worsening in 12 (3.97%) patients. Among those 28 patients with eye movement impairment at the day of discharge the improvement was marked in 10 (34.48%) patients, no changes in 11 (37.93%) patients and worsening in 6 (20.68%) patients.

All cases of worsening were associated with the tumor corresponds to grade of KNOSP III and IV. Two patients developed new III CN and one patient VI CN palsy postoperatively. At follow-up, a VI CN palsy was resolved in 3 months. Improvement of chiasmal syndrome was marked in patients with GTR, NTR, and STR—85.6% and less improvement was associated with partial removal.

Conclusion: The EEA is effective and safe approach to pituitary adenomas. Improvement of chiasmal syndrome in postoperative period associated with more radical tumor removal. Parasellar tumor extension and its more radical resection could be associated with increasing or appearance of oculomotor nerves impairment or palsy and require use meticulous microsurgical technique.