BDNF and TNF-α, OCT and VF Parameters in Pituitary Macroadenoma Patients: A 12-Month Prospective Study

Pituitary macroadenomas often cause visual pathway impairment due to optic chiasm compression. The association between systemic neurotrophic factors and visual recovery remains insufficiently explored. This prospective observational cohort study included 53 patients (106 eyes); 36 patients (72 eyes) completed a 12-month follow-up. Patients were assigned to a treatment group (surgical and/or pharmacological; n = 23) or an observation group (n = 13). Serum brain-derived neurotrophic factor (BDNF) and tumor necrosis factor-α (TNF-α) were measured at baseline and 12 months. Structural parameters (retinal nerve fiber layer [RNFL], ganglion cell-inner plexiform layer [GCIPL]) and visual field indices (mean sensitivity [MS], mean deviation [MD], square root of loss variance [sLV]) were assessed using optical coherence tomography and automated perimetry. Serum BDNF levels differed significantly between groups at baseline (p = 0.0022) and at 12 months (p < 0.0001), while TNF-α levels showed no significant changes. The treatment group demonstrated significant improvement in visual field parameters and modest RNFL thickening in the right eye (p = 0.0087). Baseline BDNF levels correlated inversely with OCT and visual field measures, particularly in non-functioning adenomas (R = -0.70 to -0.80, p < 0.01). Baseline BDNF predicted treatment qualification (AUC = 0.815). Pituitary macroadenomas are associated with visual dysfunction and systemic neurotrophic alterations. Elevated BDNF may reflect a compensatory neuroprotective response, supporting combined molecular and ophthalmic monitoring.