RT Journal Article SR Electronic T1 Shape analysis of the cingulum, uncinate and arcuate fasciculi in patients with bipolar disorder JF Journal of Psychiatry and Neuroscience JO J Psychiatry Neurosci FD Canadian Medical Association SP 27 OP 36 DO 10.1503/jpn.150291 VO 42 IS 1 A1 Sun, Zhong Yi A1 Houenou, Josselin A1 Duclap, Delphine A1 Sarrazin, Samuel A1 Linke, Julia A1 Daban, Claire A1 Hamdani, Nora A1 d’Albis, Marc-Antoine A1 Le Corvoisier, Philippe A1 Guevara, Pamela A1 Delavest, Marine A1 Bellivier, Frank A1 Almeida, Jorge A1 Versace, Amelia A1 Poupon, Cyril A1 Leboyer, Marion A1 Phillips, Mary A1 Wessa, Michèle A1 Mangin, Jean-François YR 2017 UL http://jpn.ca/content/42/1/27.abstract AB Background: Abnormal maturation of brain connectivity is supposed to underlie the dysfunctional emotion regulation in patients with bipolar disorder (BD). To test this hypothesis, white matter integrity is usually investigated using measures of water diffusivity provided by MRI. Here we consider a more intuitive aspect of the morphometry of the white matter tracts: the shape of the fibre bundles, which is associated with neurodevelopment. We analyzed the shape of 3 tracts involved in BD: the cingulum (CG), uncinate fasciculus (UF) and arcuate fasciculus (AF).Methods: We analyzed diffusion MRI data in patients with BD and healthy controls. The fibre bundles were reconstructed using Q-ball–based tractography and automated segmentation. Using Isomap, a manifold learning method, the differences in the shape of the reconstructed bundles were visualized and quantified.Results: We included 112 patients and 82 controls in our analysis. We found the left AF of patients to be further extended toward the temporal pole, forming a tighter hook than in controls. We found no significant difference in terms of shape for the left UF, the left CG or the 3 right fasciculi. However, in patients compared with controls, the ventrolateral branch of the left UF in the orbitofrontal region had a tendency to be larger, and the left CG of patients had a tendency to be smaller in the frontal lobe and larger in the parietal lobe.Limitations: This was a cross-sectional study.Conclusion: Our results suggest neurodevelopmental abnormalities in the left AF in patients with BD. The statistical tendencies observed for the left UF and left CG deserve further study.