title: Abnormal structural and functional hypothalamic connectivity in mild traumatic brain injury.
abstract: To investigate whether there is imaging evidence of hypothalamic injury in patients with mild traumatic brain injury (MTBI), which is a major public health problem due to the high prevalence and difficulty in diagnosis and treatment.
  
  
  
  Twenty-four patients (mean age 34.2, range, 18-56 years) with symptomatic MTBI and 22 age-matched healthy controls (mean age 37.0, range 20-61 years) participated in the study. Diffusion kurtosis imaging was performed with diffusion-weighted images acquired along 30 gradient directions and three b-values (b = 0, 1000, 2000 s/mm2) based on a twice-refocused spin-echo sequence with a 3T magnetic resonance imaging (MRI) scanner. Resting-state functional (f)MRI with standard echo planar imaging (EPI) were performed to localize the resting-state networks (RSN) and hypothalamic functional connectivity.
  
  
  
  There were significantly reduced mean kurtosis (P = 0.0092) and radial kurtosis (P = 0.0078) in patients as compared to controls in the hypothalamus. Furthermore, there was a significant negative correlation (r = -0.675, P = 0.0007) between radial kurtosis in the hypothalamus and fatigue severity scale in patients. The MTBI group also showed disrupted hypothalamic RSNs, with significantly decreased positive connectivity in medial prefrontal cortex, inferior posterior parietal, and cingulate regions but increased connectivity in the peri-hypothalamic regions and cerebellum, together with significantly decreased negative RSNs in visual and bilateral premotor areas (cluster corrected P < 0.05).
  
  
  
  Our results show disruption of functional and structural hypothalamic connectivity in patients with MTBI, and might further the understanding of an array of clinical symptoms in MTBI such as sleep disturbance and fatigue.
  
  
  
  2 J. Magn. Reson. Imaging 2017;45:1105-1112.
authors.affiliation: Department of Radiology / Center for Biomedical Imaging, NYU Langone Medical Center, New York, New York, USA.
authors.forename: Yongxia
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D000293:Adolescent; D000328:Adult; D000070642:Brain Injuries, Traumatic / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007031:Hypothalamus / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: diffusion kurtosis; fatigue; functional activity; functional connectivity; hypothalamus; mild traumatic brain injury