Subcortical shape in pediatric and adult obsessive‐compulsive disorder

Abstract

Background Obsessive‐compulsive disorder (OCD) implicates alterations in cortico‐striato‐thalamo‐cortical and fronto‐limbic circuits. Building on prior structural findings, this is the largest study to date examining subcortical surface morphometry in OCD. Methods Structural magnetic resonance imaging data were collected from 200 participants across development (5–55 years): 28 youth and 75 adults with OCD and 27 psychiatrically healthy youth and 70 adults. General linear models were used to assess group differences and group‐by‐age interactions on subcortical shape (FSL FIRST). Results Compared to healthy participants, those with OCD exhibited surface expansions on the right nucleus accumbens and inward left amygdala deformations, which were associated with greater OCD symptom severity ([Children's] Yale‐Brown Obsessive‐Compulsive Scale). Group‐by‐age interactions indicated that accumbens group differences were driven by younger participants and that right pallidum shape was associated inversely with age in healthy participants, but not in participants with OCD. No differences in the shape of other subcortical regions or in volumes (FreeSurfer) were detected in supplementary analyses. Conclusions This study is the largest to date examining subcortical shape in OCD and the first to do so across the developmental spectrum. NAcc and amygdala shape deformation builds on extant neuroimaging findings and suggests subtle, subregional alterations beyond volumetric findings. Results shed light on morphometric alterations in OCD, informing current pathophysiological models.

Subcortical and hippocampal brain segmentation in 5‐year‐old children: Validation of FSL‐FIRST and FreeSurfer against manual segmentation

“…Although both FSL‐FIRST and FreeSurfer were originally developed mainly for adult brain image analyses, both software have also been used in paediatric neuroimaging. There are multiple recent studies using both FSL‐FIRST (Sandman et al, 2014; Wang et al, 2022) and FreeSurfer (Barch, Harms, et al, 2019; Barch, Tillman, et al, 2019; Grohs et al, 2021; Roediger et al, 2021) as a tool for paediatric volumetric subcortical brain segmentation. Majority of these studies did not use manual segmentation as a control for segmentation accuracy.…”

Subcortical alterations in newly diagnosed epilepsy and associated changes in brain connectivity and cognition

“…In contrast, shape analyses localizes subregional morphometric differences using Bayesian models to estimate surface deformation. While various potential factors such as alterations in myelin, vasculature, and neuronal pruning contribute to localized shape variation [Serbruyns et al, 2015], a growing body of evidence suggests that subregional specificity offers additional insight into pathological brain alterations that conventional volumetric measurements cannot capture [Wang et al, 2022].…”