Factors Affecting the Visual Outcome of Pituitary Adenoma Patients Treated with Endoscopic Transsphenoidal Surgery

OBJECTIVE: To evaluate visual acuity (VA) and visual fields (VF) quantitatively before and after endoscopic transsphenoidal surgery (ETS), with special attention to prognostic factors such as the pituitary adenoma (PA) suprasellar extension (SSE), volume and the patients' age. METHODS: Medical records of 47 patients with PA undergoing ETS were evaluated. VA, VF, preoperative visual impairment score (VISpre) and postoperative visual impairment score (VISpost) were determined. The PA SSE, volume, chiasmal contact, and their correlation with visual function were assessed preoperatively and postoperatively. RESULTS: The final cohort included 47 patients. VA improved in 54 of 76 eyes (71.0%) after ETS, and 69 of 76 eyes (90.7%) gained normal VA. Postoperative VF recovery occurred in 32 of 37 eyes (86.5%). The mean change in VIS was 12.0 (95% confidence interval [CI], 7.7-16.3) and improved in all patients with tumor-related visual impairment (n = 25). However, visual outcome was poorer when VISpre was greater than 40. When VISpre was 21-40, age linearly correlated with VIS improvement (P = 0.03); younger patients had satisfactory and older poorer visual outcome. The mean SSE in patients with VF defects (n = 20) was 16.6 mm (95% CI, 13.3-19.9). Mean SSE in patients with no VF defects (n = 23) was 6.6 mm (95% CI, 4.9-8.3; P < 0.001), and the cutoff value for visual perturbations was 9.5 mm for SSE and 8.6 mL for PA volume (P < 0.001 for both). CONCLUSIONS: The visual outcome after ETS for PAs was excellent, and serious complications were rare. Severe preoperative visual impairment resulted in poorer postoperative visual outcomes. The SSE of the PA was the most important predictor of visual outcome after ETS.