Analysis of change in visual function caused by pituitary adenoma in LUHS. Neurosurgery and Endocrinology clinics. Pituitary adenoma (PA) is a benign tumor of parenchymal cells of adenohypophysis. 10 – 25% of all intracranial tumors are PA, prevalence in general population – 16,7%. A lot of patients have their visual functions (visual acuity, field of vision, color perception, contrast sensitivity) impaired because PA compresses and injures fibers of optic chiasm, also impairment of optic discs is observed so ophthalmologic examination methods are important in early PA diagnostics. Aim: To Assess changes in visual functions in patients with PA in LUHSH KC clinics of Neurosurgery and Endocrinology from 2009-01-01 to 2013-12-31. Methods: A retrospective analysis of 154 patients (308 eyes) treated in LUHSH KC clinics of Neurosurgery and Endocrinology from 2009-01-01 to 2013-12-31 case-histories with PA was conducted. Diagnosis of PA was confirmed by CT scan or MRI. Patients age, gender, best preoperative corrected visual acuity (V), size and invasiveness of tumor, changes in field of vision and optic disc were evaluated. Statistic analysis was performed using SPSS 21.1 software package. Statistical connection of qualitative variables was evaluated using Pearson Chi square test and the strength of relation was evaluated using Cramer’s V correlation coefficient. Data considered statistically significant when p<0,05. Results: Data from case-histories of 154 patients (308 eyes) with PA was analyzed. Best corrected visual acuity 1,0 was assessed in 144 eyes(46,8%), 0,9 – 0,5 in 57 eyes (18,5%), 0,4 – 0,1 in 36 eyes (11,7%), 0,01 – 0,09 in 18 eyes (5,8%), visual acuity 0 in 17 eyes (5,5%). Visual acuity was not assessed in 36 eyes (11,7%). Defects of field of vision were diagnosed in 92 eyes (29,9%): bitemporal hemianopsy diagnosed in 80 eyes (26%), narrowing of temporal field of vision in 10° was diagnosed in 1 eye (0,3%), concentric narrowing of field of vision was diagnosed in 11 eyes (3,6%). No defects in field of vision were diagnosed in 161 eye (52,3%). Conclusions: 1. Visual acuity corrected up to 1,0 for almost half of the patients with PA. Almost one third of eyes assessed were diagnosed with defects of field of vision, mostly bitemporal hemianopsy. Changes in optic disc were diagnosed for 42,8% of eyes, mostly it was optic nerve atrophy. About 80% of patients were diagnosed with invasive pituitary macroadenoma. 2 More significant changes in visual acuity and field of vision were assessed in patients with invasive PA and pituitary macroadenoma. In patients with non-invasive microadenoma changes were minimal or there were none.3. It was determined that best visual acuity and changes in optic disc were statistically significantly related to patients age.