Cortical thinning and caudate abnormalities in first episode psychosis and their association with clinical outcome

Abstract

First episode psychosis (FEP) has been associated with structural brain changes, largely identified by volumetric analyses. Advances in neuroimaging processing have made it possible to measure geometric properties that may identify subtle structural changes not appreciated by a measure of volume alone. In this study we adopt complementary methods of assessing the structural integrity of grey matter in FEP patients and assess whether these relate to patient clinical and functional outcome at 3 year follow-up. 1.5 Tesla T1-weighted Magnetic Resonance (MR) images were acquired for 46 patients experiencing their first episode of psychosis and 46 healthy controls. Cerebral cortical thickness and local gyrification index (LGI) were investigated using FreeSurfer software. Volume and shape of the hippocampus, caudate and lateral ventricles were assessed using manual tracing and spherical harmonics applied for shape description. A cluster of cortical thinning was identified in FEP compared to controls; this was located in the right superior temporal gyrus, sulcus, extended into the middle temporal gyrus (lateral temporal cortex -LTC). Bilateral caudate volumes were significantly lower in FEP relative to controls and the right caudate also displayed regions of shape deflation in the FEP group. No significant structural abnormalities were identified in cortical LGI or hippocampal or lateral ventricle volume/shape. Neither LTC nor caudate abnormalities were related to change in symptom severity or global functioning 3 years later. LTC and caudate abnormalities are present at the first episode of psychosis but do not appear to directly affect clinical or functional outcome.

Anatomical integration and rich-club connectivity in euthymic bipolar disorder

“…Thirty-five participants between 18 and 60 years of age were recruited from the local community as part of the Galway Bipolar Study (Emsell, Leemans, et al 2013;Emsell, Langan, et al 2013). An additional seven individuals with remitted BD participated in a follow-up imaging of a first episode psychosis study and underwent an identical scanning procedure were included in connectivity analysis (Scanlon et al 2014;Kenney et al 2015). We recruited 43 age and gender matched healthy volunteers from the local community.…”

Cognitive course in first-episode psychosis and clinical correlates: A 4 year longitudinal study using the MATRICS Consensus Cognitive Battery

“…All subjects were aged between 18-49 years at baseline ( Table 2). The recruitment and clinical assessment of these individuals is described previously (McFarland et al, 2013;Scanlon et al, 2014). Exclusion criteria for both groups were as follows: a history of neurological disorders (including epilepsy), comorbid substance or alcohol abuse in the last year, a history of head injury resulting in loss of consciousness for over 5 minutes, a history of oral steroid use in the previous three months, loss of weight in excess of 12% of the original body weight in the previous year and a history of viral infection in previous 1 month.…”

Volume and shape analysis of subcortical brain structures and ventricles in euthymic bipolar I disorder

“…The lateral ventricles were first automatically segmented using FreeSurfer software (Fischl et al, 2002) and then edited manually by a trained rater in ITKsnap (Fig.1). Anatomical guidelines for the tracing of the hippocampus, ventricles and caudate nucleus are available in Supplementary Material (Scanlon et al, 2014). An established tracing protocol was used for the amygdala (Schumann et al, 2004).…”