Predicting the early visual outcomes in sellar-suprasellar lesions compressing the chiasm: the role of SD-OCT series of 20 patients operated via endoscopic endonasal approach

BACKGROUND Tumors involving the sellar area often cause visual disorders due to optic nerves/chiasm compression, so that surgery is required. However the likelihood of visual improvement/restoration is variable. Optical coherence tomography (OCT) is a valid diagnostic tool for defining pathological conditions of the optic apparatus. We herein investigated the role of the SD-OCT and the best corrected visual acuity in predicting postoperative visual recovery, in patients complaining of chiasm compression due to sellar-suprasellar lesions. MATERIALS AND METHODS We retrospectively analyzed 20 patients (7 females and 13 males; mean age 50,8 ± 17,87 years, range 11-83), with optic chiasm/nerve compression that underwent endoscopic endonasal approach at the Division of Neurosurgery of the Universita degli Studi di Napoli "Federico II", Naples - Italy, between June 2014 and February 2015. Pre-operative ophthalmological assessment focused on BCVA Snellen charts, Standard Automated Perimetry test and SD-OCT. Test were repeated at two weeks, one and three months after surgery. RESULTS A significant thickness reduction in all the patients, as compared to the control group was noted: GCC thickness reduction remained mostly unchanged postoperatively. 42.9% of the patients had altered visual acuity (VA), while the Perimetry revealed 90% of altered preoperative MD values (MD> -2.00): perimetry improvement was noted in 93% of cases and visual acuity in 91.3% of cases. A direct correlation between preoperative retinal status and functional recovery was identified considering the values of pRNFL and GCC. CONCLUSIONS OCT provides valuable information in regards to the entity of compression also in patients without any visual field defects. Although several factors should be taken into consideration, we retain that preoperative RNFL and GCC thickness values can be claimed as a reliable predictors of visual recovery in those patients presenting chiasm compression.