Introduction: Adult patients with craniopharyngioma (CP) and hypothalamic (HT) damage have impaired cognitive function. The white matter (WM) changes behind these findings remain to be elucidated. Diffusion tensor imaging (DTI) is a MRI technique that quantifies microstructural damage in the WM. This is the first study of DTI, hippocampal (HC) and HT volume in relation to cognition in CP patients.
Methods: A cross-sectional study of childhood onset CP was performed at median 22 years after first operation. After exclusions, 36 patients and 31 controls remained in the MRI study. Main outcome measures were comparison of cognitive tests, volume measurements of HC and HT and the DTI parameters median diffusivity (MD) and fractional anisotropy (FA) between patients and controls.
Results: CP patients have WM damage in the left dorsal cingulum and right uncinate fasciculus. No significant difference was found on DTI measurements of the HC. Correlations were found between DTI results from the right uncinated fasciculus (MD, P=0.035 and FA, P=0.005) and the left HC (MD, P=0.035 and FA, P=0.001) with long term memory reflecting general knowledge. DTI in the cingulum correlated with visual memory (MD, P≤0.04 and FA, P≤0.04) and short term memory (MD, P=0.004). DTI in the HC correlated with long term memory (MD, P=0.03 and FA, P≤0.046) and short term memory (FA, P=0.02). HT volume correlated negatively with MD of right uncinate fasciculus (P=0.015). The CP patients had a smaller HC volume which correlated with long term memory (P=0.016).
Conclusions: A structure to function relationship is established between cognition and WM damage detected with DTI in CP. CP patients have a smaller HC compared to controls. Whether the cognitive deficits are a direct consequence of HT damage or an indirect effect on frontotemporal network remains to be elucidated.
20 - 23 May 2017
European Society of Endocrinology