Correspondence between patterns of cerebral blood flow and structure in adolescents with and without bipolar disorder

Abstract

Adolescence is a period of rapid development of the brain’s inherent functional and structural networks; however, little is known about the region-to-region organization of adolescent cerebral blood flow (CBF) or its relationship to neuroanatomy. Here, we investigate both the regional covariation of CBF MRI and the covariation of structural MRI, in adolescents with and without bipolar disorder. Bipolar disorder is a disease with increased onset during adolescence, putative vascular underpinnings, and evidence of anomalous CBF and brain structure. In both groups, through hierarchical clustering, we found CBF covariance was principally described by clusters of regions circumscribed to the left hemisphere, right hemisphere, and the inferior brain; these clusters were spatially reminiscent of cerebral vascular territories. CBF covariance was associated with structural covariance in both the healthy group (n = 56; r = 0.20, p < 0.0001) and in the bipolar disorder group (n = 68; r = 0.36, p < 0.0001), and this CBF-structure correspondence was higher in bipolar disorder ( p = 0.0028). There was lower CBF covariance in bipolar disorder compared to controls between the left angular gyrus and pre- and post-central gyri. Altogether, CBF covariance revealed distinct brain organization, had modest correspondence to structural covariance, and revealed evidence of differences in bipolar disorder.

Associations of white matter hyperintensities with networks of gray matter blood flow and volume in midlife adults: A coronary artery risk development in young adults magnetic resonance imaging substudy

“…It is, however, important to note that this choice has been evaluated mainly in the context of more traditional forms of brain network analysis (i.e., functional connectivity via fMRI, structural connectivity via DTI), and not covariance analysis (Arslan et al, 2018;Zalesky et al, 2010). Indeed, other covariance studies that do report on several atlases show little to no effect on downstream results (Alexander-Bloch, Raznahan, et al, 2013;Liu et al, 2016;Luciw et al, 2021). Validation studies using external cohort data and alternative parcellation schemes would be desirable to corroborate the findings of the current study.…”

“…At the group‐level, CBF covariance captures stable relationships of inter‐regional CBF across participants. Several biological factors are thought to affect CBF covariance, including synchronized neuronal activity via neurovascular coupling, structural connectivity, and shared vascular supply (Luciw et al, 2021 ; Melie‐García et al, 2013 ). Importantly, structural covariance networks and covariance networks derived from CBF (as well as other physiological neuroimaging contrasts, such as glucose metabolism) exhibit significant yet modest correspondence, suggesting that they provide complementary but distinct information (Di et al, 2017 ; Luciw et al, 2021 ).…”

“…Several biological factors are thought to affect CBF covariance, including synchronized neuronal activity via neurovascular coupling, structural connectivity, and shared vascular supply (Luciw et al, 2021 ; Melie‐García et al, 2013 ). Importantly, structural covariance networks and covariance networks derived from CBF (as well as other physiological neuroimaging contrasts, such as glucose metabolism) exhibit significant yet modest correspondence, suggesting that they provide complementary but distinct information (Di et al, 2017 ; Luciw et al, 2021 ). Therefore, given that CBF covariance can provide metabolic and vascular information, it is important to consider this imaging contrast alongside structural covariance (Luciw et al, 2021 ; Melie‐García et al, 2013 ).…”

Associations of white matter hyperintensities with networks of grey matter blood flow and volume in midlife adults: a CARDIA MRI substudy

“…CBF covariance matrices were partitioned into three modules that were consistent between Lo-and Hi-WMH groups. Luciw et al found that communities derived from CBF covariance patterns in adolescents are spatially similar to the brain's vascular territories (Luciw et al, 2021). Melie-García et al observed strong CBF covariance between bilateral brain regions in healthy adults (Melie-García et al, 2013).…”

“…Cerebral blood flow (CBF) is an important proxy of brain health and metabolism that is amenable to covariance analysis. CBF covariance networks are thought to convey metabolic and vascular information that may be complementary to network analyses performed with structural covariance, blood-oxygenation level-dependent functional MRI (fMRI) or diffusion tensor imaging (DTI) (Luciw et al, 2021;Melie-García et al, 2013).…”