[Optical coherence tomography as a predictor of visual recovery in patients with pituitary macroadenomas]

With pituitary macroadenomas, there is a high incidence of visual loss from optic pathway compression. Surgical removal of the tumor usually prevents progression and allows visual recovery. Our objective was to evaluate if optical coherence tomography (OCT) predicts visual outcomes after surgical decompression.

Patients with pituitary macroadenomas were prospectively recruited between February 2015 and November 2016. We evaluated preoperative and postoperative visual acuity, automated perimetry, and OCT. We compared the results 6-12 weeks and 6-9 months after surgical removal of the tumor. Dependent and independent continuous variables were analyzed by Student's t-test, linear regression analysis, and Pearson's correlation coefficients, considering P < 0.05 as statistically significant.

Visual acuity and visual field defects were much worse in patients with a thin preoperative retinal nerve fiber layer (RNFL). Both patients with normal RNFL thickness and patients with thin RNFL experienced significant improvement in postoperative visual perimetry 6-12 weeks after surgery. OCT values correlated inversely with pre- and postoperative visual fields, which means that, if the nerve was thicker, the visual field was better. Patients with a normal OCT had greater recovery because their preoperative perimetry values were better. The correlation between OCT values and visual field improvement was weak, suggesting that patients' visual fields improved after decompressive surgery independent of the nerve's thickness.

The computerized visual field continues to be the gold standard in the evaluation of patients with pituitary macroadenomas with optic pathway compression. Our results suggest that OCT might not be an accurate predictor of visual outcomes.