Evaluation of patients diagnosis with prolactinomas with volume and morphometric parameters obtained from 3D high-resolution T1 weighted brain images and examination of the relationship of structural changes with neurocognitival tests

Aim: The aim of this study is to evaluate the morphometric characteristics of the brain cortex surface in patients diagnosed with prolactinoma and to compare these findings with healthy controls, in order to identify the effects of this disease on cortical brain structures. Materials and Methods: This study included 45 patients diagnosed with prolactinoma who were under follow-up and treatment at Istanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine Hospital, Department of Internal Medicine, Endocrinology Clinic, along with 51 healthy control individuals. Participants with similar age and gender characteristics were included across the groups. The study assessed brain cortex surface morphometric characteristics using ROI analysis and vertex-wise analysis models. Surface cortical morphometric parameters such as cortical thickness, sulcal depth, fractal dimensionality, and gyrification were compared between patients diagnosed with prolactinoma and healthy controls. Results: ROI analysis revealed significant reductions in cortical thickness in the right lingual gyrus, right cuneus, right parahippocampal gyrus, right entorhinal gyrus, right lateral orbitofrontal cortex, right insula, left cuneus, left insula, and left entorhinal gyrus in patients with prolactinoma compared to healthy controls. Additionally, significant reductions in sulcal depth in the right insula and left pars orbitalis, as well as in the gyrification index of the right supramarginal gyrus, were observed in prolactinoma patients compared to healthy controls. Vertex-wise analysis identified six cortical clusters (left insular cortex, right lateral occipital gyrus, right lateral and medial orbitofrontal cortex, right insular cortex, and right superior temporal gyrus) with significant reductions in cortical thickness in prolactinoma patients. Conclusion: One of the most notable findings of our study is the significant reduction in cortical thickness and sulcal depth in the insula of prolactinoma patients compared to healthy controls, as identified in both ROI-based and vertex-wise analyses. Moreover, a positive correlation was observed between sulcal depth and cabergoline dose, as well as between cortical thickness and letter fluency test scores. These findings are expected to contribute significantly to the existing literatüre