Decreased cortical thickness on MRI in patients with Cushing's syndrome: preliminary experience
Alicia Santos1, Esther Granell3, Eugenia Resmini1, Juan Ybarra1, Maria J Portella2, Victor Perez2, Maria J Barahona1, Olga López Mourelo3, Yolanda Vives4, Manuel De Juan4, Patricia Pires3, Beatriz Gómez Anson4 & Susan Webb1
Introduction: Patients with Cushings syndrome might present a variety of brain alterations. There is however little evidence from MRI studies demonstrating atrophy of either frontal or medial temporal brain regions.
Aims: To study cortical alterations (decreased cortical thickness) on MRI in patients with Cushings syndrome (CS), as compared to controls (C), and long-standing major depressive disorder (MDD).
Material and methods: Thirteen patients with CS (3 with active disease), 14 controls and 19 MDD patients were evaluated. MRI was obtained using a 3T Philips Achieva facility (software version 220.127.116.11), the SENSE 8-channel head-coil, and a specifically designed acquisition protocol (3D-MPRAGE whole brain sequence, Turbo Field Echo, TR=6.7, TE=3.1, Voxel size=1×1×1.2). Cortical thickness was quantified using a MRI automatic software package (FreeSurfer), running on a GRID facility in a parallel environment. The results of the cortical thickness were verified by experts, and in some cases manual modifications were applied to obtain more accurate results. The Freesurfer statistical package (QDEC tool) was used to perform the comparisons between groups. Significance was defined at P<0.05.
Results: ANOVA results showed differences among the three groups in several brain regions. CS patients displayed decreased cortical thickness in the posterior cingulate, prefrontal and lateral temporal regions, of both cerebral hemispheres compared to controls (df=23; P<0.05). CS patients also showed decreased cortical thickness in the posterior cingulate and lateral temporal regions (even more pronounced) compared to MDD (df=28; P=0.01). These differences were maintained when age, gender and years of education were included as covariates.
Conclusions: Cushings syndrome patients show a distinct pattern of cortical alterations, as observed on MRI analyses, from controls and major depressive disorder. These findings could influence the cognitive performance of Cushings syndrome patients.
Supported by FIS080302 and ERCUSYN PHP800200.