title: Morphological alterations in amygdalo-hippocampal substructures in narcolepsy patients with cataplexy.
abstract: Although the role of hypocretin-mediated amygdalo-hippocampal dysfunction is hypothesized to be linked with narcolepsy, there have been no human MRI studies investigating the relationship between their regional volume and key symptoms of narcolepsy. To investigate the morphological changes of amygdalo-hippocampus and its relationship with clinical features in patients with narcolepsy, point-wise morphometry that allowed for measuring the regional volumes of amygdalo-hippocampus on T1-weighted MRI was applied. Participants were 33 drug-naïve patients and 35 age-/gender-matched controls (mean ± SD: 27 ± 6 years). We compared hippocampal and amygdalar subfields volumes between patients and controls and correlated between volume and clinical and neuropsychological features in patients. Bilateral hippocampal atrophy (183 vertices) was identified mainly located within the CA1 subfield (FDR < 0.05). Significant amygdalar volume reduction was found in the areas of the centromedial (102 vertices) and laterobasal nuclear groups (LB, 35 vertices). There was no volume increase in patients relative to controls (FDR >0.2). After controlling depressive mood, sleep quality, age, and gender, hippocampal CA1 atrophy and amygdalar centromedial atrophy were associated with longer duration of daytime sleepiness and shorter mean REM sleep latency (|r| >0.44, p < 0.01). The amygdalar centromedial atrophy was associated with longer duration of cataplexy (|r| >0.47, p < 0.005). Subfields atrophy of amygdalo-hippocampus in untreated patients with narcolepsy that was found relative to controls suggests that CA1 of the hippocampus and centromedial area of amygdala are closely related to the severity of narcolepsy and play a crucial role in the circuitry of cataplexy.
authors.affiliation: Department of Neurology, Neuroscience Center, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Korea.|Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Hosung
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Psychology, Sungshin Women's University, Seoul, Korea.|Department of Psychiatry, Stanford University, Redwood City, CA, USA.
authors.forename: Sooyeon
authors.initials: S
authors.lastname: Suh
authors.affiliation: Department of Neurology, Neuroscience Center, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Korea. ejoo@skku.edu.
authors.forename: Eun Yeon
authors.initials: EY
authors.lastname: Joo
authors.affiliation: Department of Neurology, Neuroscience Center, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 135-710, Korea. sbhong@skku.edu.
authors.forename: Seung Bong
authors.initials: SB
authors.lastname: Hong
mesh_terms: D000328:Adult; D000679:Amygdala / Q000000981:diagnostic imaging*; D001284:Atrophy / Q000000981:diagnostic imaging; D002385:Cataplexy / Q000000981:diagnostic imaging* / Q000523:psychology; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D009929:Organ Size; D057566:Self Report
keywords: Amygdale; Hippocampus; MRI volumetry; Narcolepsy; Surface analysis