title: Cine magnetic resonance imaging of spinal intradural arachnoid cysts.
abstract: OBJECTIVE
  The diagnostic value of cine magnetic resonance imaging (CMRI) that visualizes fluid and tissue movement was evaluated in patients with spinal intradural arachnoid cysts, a rare but increasingly detected cause of spinal cord dysfunction.
  
  
  METHODS
  Four patients with thoracic spinal intradural arachnoid cysts were investigated with conventional T1- and T2-weighted and cardiac-gated CMRI. Four normal volunteers also underwent CMRI for comparison.
  
  
  RESULTS
  Sagittal T1- and T2-weighted imaging showed lesions as an abnormal widening of the posterior spinal subarachnoid space, but mixed high- and low-signal intensities on T2-weighted imaging suggested cystic lesions. CMRI, using 16 to 20 sagittal gradient echo images during the cardiac cycle of normal volunteers, indicated synchronous signal changes along the subarachnoid space, suggesting a smooth cerebrospinal fluid flow. CMRI of patients detected that the caudal or cranial direction of the high-signal propagation suddenly reversed at some locations (as if rebounding) in an asynchronous fashion along the lesion (asynchronous rebound phenomenon), which was well demonstrated by the closed-loop video mode. Cystectomy revealed that the cysts consisted of multiple lobules and that the asynchronous rebound phenomenon corresponded with some boundaries of cyst lobules. CMRI also visualized dynamic spinal cord compression by the cyst.
  
  
  CONCLUSIONS
  CMRI can demonstrate abnormal fluid flow and spinal cord compression caused by a spinal intradural arachnoid cyst.
authors.affiliation: Department of Neurosurgery, Kohnan Hospital, Sendai, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shimizu
authors.forename: T
authors.initials: T
authors.lastname: Tominaga
authors.forename: A
authors.initials: A
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Yoshimoto
mesh_terms: D000328:Adult; D016080:Arachnoid Cysts / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D007796:Laminectomy; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013116:Spinal Cord / Q000473:pathology; D013117:Spinal Cord Compression / Q000175:diagnosis* / Q000601:surgery; D013346:Subarachnoid Space / Q000473:pathology; D016896:Treatment Outcome