Clinical MRI morphological analysis of functional seizures compared to seizure-naïve and psychiatric controls
Wesley T. Kerr, Hiroyuki Tatekawa, John K. Lee, Amir H. Karimi, Siddhika S. Sreenivasan, Joseph O’Neill, Jena M. Smith, L. Brian Hickman, Ivanka Savic, Nilab Nasrullah, Randall Espinoza, Katherine L. Narr, Noriko Salamon, Nicholas J. Beimer, Lubomir M. Hadjiiski, Dawn Eliashiv, William C. Stacey, Jerome Engel, Jamie D. Feusner, John M. Stern
Abstract
PURPOSE: Functional seizures (FS), also known as psychogenic nonepileptic seizures (PNES), are physical manifestations of acute or chronic psychological distress. Functional and structural neuroimaging have identified objective signs of this disorder. We evaluated whether magnetic resonance imaging (MRI) morphometry differed between patients with FS and clinically relevant comparison populations. METHODS: Quality-screened clinical-grade MRIs were acquired from 666 patients from 2006 to 2020. Morphometric features were quantified with FreeSurfer v6. Mixed-effects linear regression compared the volume, thickness, and surface area within 201 regions-of-interest for 90 patients with FS, compared to seizure-naïve patients with depression (n = 243), anxiety (n = 68), and obsessive-compulsive disorder (OCD, n = 41), respectively, and to other seizure-naïve controls with similar quality MRIs, accounting for the influence of multiple confounds including depression and anxiety based on chart review. These comparison populations were obtained through review of clinical records plus research studies obtained on similar scanners. RESULTS: , p = 0.0065). These findings were not accounted for by lower MRI quality in patients with FS. CONCLUSIONS: These results reinforce prior indications of structural neuroimaging correlates of FS and, in particular, distinguish brain morphology in FS from that in depression, anxiety, and OCD. Future work may entail comparisons with other psychiatric disorders including bipolar and schizophrenia, as well as exploration of brain structural heterogeneity within FS.