Georgios D Argyropoulos1, Foteini Christidi2, Efstratios Karavasilis1, Georgios Velonakis1, Anastasia Antoniou3, Peter Bede4, Ioannis Seimenis5, Nikolaos Kelekis1, Athanasios Douzenis3, Olympia Papakonstantinou1, Efstathios Efstathopoulos1, Panagiotis Ferentinos3. 1. Research Unit of Radiology and Medical Imaging, 2nd Department of Radiology, Attikon General University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece. 2. 2nd Department of Psychiatry, Attikon General University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece; Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, Athens, Greece. Electronic address: christidi.f.a@gmail.com. 3. 2nd Department of Psychiatry, Attikon General University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece. 4. Biomedical Imaging Laboratory, Sorbonne University, CNRS, INSERM, Paris, France; Computational Neuroimaging Group, Trinity College Dublin, Ireland. 5. Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
Abstract
BACKGROUND: The cerebellum has a crucial role in mood regulation. While cerebellar grey matter (GM) alterations have been previously reported in bipolar disorder (BD), cerebro-cerebellar white matter (WM) connectivity alterations and cerebellar GM profiles have not been characterised in the context of predominant polarity (PP) and onset polarity (OP) subphenotypes of BD patients which is the aim of the present study. METHODS: Forty-two euthymic BD patients stratified for PP and OP and 42 healthy controls (HC) were included in this quantitative neuroimaging study to evaluate cerebellar GM patterns and cerebro-cerebellar WM connections. Diffusion tensor tractography was used to characterise afferent and efferent cerebro-cerebellar tract integrity. False discovery rate corrections were applied in post-hoc comparisons. RESULTS: BD patients exhibited higher fractional anisotropy (FA) in fronto-ponto-cerebellar tracts bilaterally compared to HC. Subphenotype-specific FA profiles were identified within the BD cohort. Regarding PP subgroups, we found FA changes in a) left contralateral fronto-ponto-cerebellar tract (depressive-PP > HC) and b) contralateral/ipsilateral fronto-ponto-cerebellar tracts bilaterally (manic-PP > HC). Regarding OP subgroups, we observed FA changes in a) left/right contralateral fronto-ponto-cerebellar tracts (depressive-OP > HC) and b) all fronto-ponto-cerebellar, most parieto-ponto-cerebellar and right contralateral occipito-ponto-cerebellar tracts (manic-OP>HC). In general, greater and more widespread cerebro-cerebellar changes were observed in manic-OP patients than in depressive-OP patients compared to HC. Manic-OP showed higher FA compared to depressive-OP patients in several afferent WM tracts. No GM differences were identified between BD and HC and across BD subgroups. CONCLUSIONS: Our findings highlight fronto-ponto-cerebellar connectivity alterations in euthymic BD. Polarity-related subphenotypes have distinctive cerebro-cerebellar WM signatures with potential clinical and pathobiological implications.
BACKGROUND: The cerebellum has a crucial role in mood regulation. While cerebellar grey matter (GM) alterations have been previously reported in bipolar disorder (BD), cerebro-cerebellar white matter (WM) connectivity alterations and cerebellar GM profiles have not been characterised in the context of predominant polarity (PP) and onset polarity (OP) subphenotypes of BD patients which is the aim of the present study. METHODS: Forty-two euthymic BD patients stratified for PP and OP and 42 healthy controls (HC) were included in this quantitative neuroimaging study to evaluate cerebellar GM patterns and cerebro-cerebellar WM connections. Diffusion tensor tractography was used to characterise afferent and efferent cerebro-cerebellar tract integrity. False discovery rate corrections were applied in post-hoc comparisons. RESULTS: BD patients exhibited higher fractional anisotropy (FA) in fronto-ponto-cerebellar tracts bilaterally compared to HC. Subphenotype-specific FA profiles were identified within the BD cohort. Regarding PP subgroups, we found FA changes in a) left contralateral fronto-ponto-cerebellar tract (depressive-PP > HC) and b) contralateral/ipsilateral fronto-ponto-cerebellar tracts bilaterally (manic-PP > HC). Regarding OP subgroups, we observed FA changes in a) left/right contralateral fronto-ponto-cerebellar tracts (depressive-OP > HC) and b) all fronto-ponto-cerebellar, most parieto-ponto-cerebellar and right contralateral occipito-ponto-cerebellar tracts (manic-OP>HC). In general, greater and more widespread cerebro-cerebellar changes were observed in manic-OP patients than in depressive-OP patients compared to HC. Manic-OP showed higher FA compared to depressive-OP patients in several afferent WM tracts. No GM differences were identified between BD and HC and across BD subgroups. CONCLUSIONS: Our findings highlight fronto-ponto-cerebellar connectivity alterations in euthymic BD. Polarity-related subphenotypes have distinctive cerebro-cerebellar WM signatures with potential clinical and pathobiological implications.
Authors: Mary Clare McKenna; Rangariroyashe H Chipika; Stacey Li Hi Shing; Foteini Christidi; Jasmin Lope; Mark A Doherty; Jennifer C Hengeveld; Alice Vajda; Russell L McLaughlin; Orla Hardiman; Siobhan Hutchinson; Peter Bede Journal: J Neurol Date: 2021-05-13 Impact factor: 6.682
Authors: Giusy Olivito; Michela Lupo; Andrea Gragnani; Marco Saettoni; Libera Siciliano; Corinna Pancheri; Matteo Panfili; Mara Cercignani; Marco Bozzali; Roberto Delle Chiaie; Maria Leggio Journal: Cerebellum Date: 2021-08-25 Impact factor: 3.648