title: Abnormal Spontaneous Brain Activity in Acute Low-Back Pain Revealed by Resting-State Functional MRI.
abstract: OBJECTIVE
  Neuroimaging studies have revealed that low-back pain (LBP) alters spatiotemporal dynamics of the blood oxygen level-dependent signal in response to persistent noxious stimulus. This study aimed to investigate changes in spontaneous neural activity of various brain regions in acute LBP using resting-state functional magnetic resonance imaging and amplitude of low-frequency fluctuation (ALFF).
  
  
  METHODS
  Twelve healthy subjects underwent two separate resting-state functional magnetic resonance imaging scans at health status as baseline and after intramuscular injection of hypertonic saline (0.5 mL, 5%) into the back muscles to induce acute LBP.
  
  
  RESULTS
  Compared with baseline, acute LBP showed decreased ALFF in the right posterior cingulate cortex/precuneus and left primary somatosensory cortex (S1) but increased ALFF in the right medial prefrontal cortex, right middle temporal gyrus, bilateral inferior temporal gyrus, bilateral insula, right anterior cingulate cortex, and left cerebellum. In addition, significant negative correlations were observed between visual analog scale scores and ALFF of the bilateral medial prefrontal cortex, left inferior frontal gyrus, left S1, right anterior cingulate cortex, and left middle temporal gyrus.
  
  
  CONCLUSIONS
  These findings suggest that abnormally spontaneous neural activity involving some brain regions are responsible for sensory, affective, and cognitive functions, which may be implicated in the underlying pathophysiology of acute LBP.
authors.affiliation: From the Department of Rehabilitation Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China (SZ, CW); and Departments of Rehabilitation Medicine (WW) and Radiology (JY), Zhujiang Hospital, Southern Medical University, Guangzhou, PR China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Zhang
authors.forename: Wen
authors.initials: W
authors.lastname: Wu
authors.forename: Jian-Ming
authors.initials: JM
authors.lastname: Yang
authors.forename: Chu-Huai
authors.initials: CH
authors.lastname: Wang
mesh_terms: D059787:Acute Pain / Q000503:physiopathology*; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D064232:Visual Analog Scale; D055815:Young Adult