[Visual functional changes in patients with pituitary adenoma: results of transnasal-transsphenoidal tumor removal]

The study was based on the analysis of case histories of 371 patients with pituitary adenoma who were examined and treated at the Acad. N. N. Burdenko Institute of Neurosurgery in 1999 to 2004. The patients' age was 13 to 75 years; the peak of the disease fell on the age of 40-50 years. Females were 61% and males 39%. The symmetrical and asymmetric chiasmal syndrome was detected in 42 and 58% of patients, respectively. Early chismal syndrome was identified in 32% of patients; insignificant and significant one being in 27 and 41%, respectively. According to the stage of visual disorders, the patients were divided as follows: those with an early stage (62.9%) and those with a late stage (37.1%). An analysis has indicated that the pattern of visual disorders correlates with the site, predominant growth, and sizes of a tumor. Early postoperative visual functions restore mainly in patients with early-stage visual disorders, which is accounted for by timely decompression of visual fibers and their better blood supply. Functional block cessation, axonal transport recovery, and, probably, visual fiber remyelination result in positive changes in the late postoperative period.