Microstructural white matter alterations and hippocampal volumes are associated with cognitive deficits in craniopharyngioma

Context Patients with craniopharyngioma (CP) and hypothalamic lesions (HL) have cognitive deficits. Which neural pathways are affected is unknown. Objective To determine whether there is a relationship between microstructural white matter (WM) alterations detected with diffusion tensor imaging (DTI) and cognition in adults with childhood-onset CP. Design A cross-sectional study with a median follow-up time of 22 (6–49) years after operation. Setting The South Medical Region of Sweden (2.5 million inhabitants). Participants Included were 41 patients (24 women, ≥17 years) surgically treated for childhood-onset CP between 1958–2010 and 32 controls with similar age and gender distributions. HL was found in 23 patients. Main outcome measures Subjects performed cognitive tests and magnetic resonance imaging, and images were analyzed using DTI of uncinate fasciculus, fornix, cingulum, hippocampus and hypothalamus as well as hippocampal volumetry. Results Right uncinate fasciculus was significantly altered (P ≤ 0.01). Microstructural WM alterations in left ventral cingulum were significantly associated with worse performance in visual episodic memory, explaining approximately 50% of the variation. Alterations in dorsal cingulum were associated with worse performance in immediate, delayed recall and recognition, explaining 26–38% of the variation, and with visuospatial ability and executive function, explaining 19–29%. Patients who had smaller hippocampal volume had worse general knowledge (P = 0.028), and microstructural WM alterations in hippocampus were associated with a decline in general knowledge and episodic visual memory. Conclusions A structure to function relationship is suggested between microstructural WM alterations in cingulum and in hippocampus with cognitive deficits in CP.