Factors influencing improvement of visual field after trans-sphenoidal resection of pituitary macroadenomas: a retrospective cohort study

Abstract

Aim: To investigate the influencing factors of visual field improvement after trans-sphenoidal resection of pituitary macroadenomas.

Methods: This retrospective cohort study included 201 patients (366 eyes) with visual field defect induced by pituitary macroadenomas. All of them were treated with trans-sphenoidal surgery. Ophthalmologic evaluation, best-corrected visual acuity (BCVA), and visual field examination were performed before and 3mo after surgery. BCVA, visual field defect index mean deviation (MD), duration of symptoms, age, sex, and volume of tumors were compared. Expression of vascular endothelial growth factor (VEGF) and Ki-67 of tumor tissue were detected by immunohistochemical technique.

Results: The mean age of patients was 44.23±1.29y. Ninety-three patients were female and 108 were male. The mean tumor volume was 14.36±6.23 cm(3). The mean duration of preoperative symptoms was 11.50±0.88mo. Mean preoperative MD was -17.50±0.82 dB. Mean Preoperative visual acuity was 0.64±0.04. Postoperative visual field improved in 270 (73.77%) eyes, unchanged in 96 (26.23%) eyes. Multivariate logistic regression displayed that the factors independently influencing visual field improvement were young age (OR=1.71, 95%CI: 1.325-2.387, P=0.013), low preoperative MD absolute value (OR=1.277, 95%CI: 1.205-1.355, P<0.001), small volume of tumor (OR=1.458, 95%CI: 1.060-4.289, P<0.001), low expression of VEGF in tumor tissue (OR=1.554, 95%CI: 1.089-2.457, P=0.022), and low expression of Ki-67 in tumor tissue (OR=1.552, 95%CI: 1.161-2.847, P=0.026).

Conclusion: After pituitary macroadenomas trans-sphenoidal resection, the independent influencing factors of the visual fields recovery were low preoperative MD absolute value, young age, small volume of tumor, and expression levels of VEGF/ Ki-67.

Keywords: Ki-67; influencing factors; pituitary adenoma; vascular endothelial growth factor; visual field.

Figure 1. Representative images of immunohistochemical staining for VEGF in pituitary adenomas tissues (HP, ×400). Microscopy showed that the brown granules in the tumor cell cytoplasm

A: A negative immunohistochemical assay, the score was 1; B: A positive immunohistochemical assay, the score was 6.

Figure 2. Representative images of immunohistochemical staining for Ki-67 in pituitary adenomas tissues (HP, ×400). Microscopy showed that the brown granules in cell nucleus

A: A negative immunohistochemical assay, the Ki-67 LI was <1%; B: A positive immunohistochemical assay, the Ki-67 LI was 5%.