title: Three-dimensional imaging for presentation of the causative vessels in patients with hemifacial spasm and trigeminal neuralgia.
abstract: BACKGROUND
  In patients with hemifacial spasm and trigeminal neuralgia, preoperative detection of the relationship between the blood vessels and the cranial nerves involved is essential.
  
  
  METHODS
  We studied the causative vessels in 20 patients with hemifacial spasm and six patients with trigeminal neuralgia by means of magnetic resonance (MR) imaging with spoiled gradient recalled acquisition in the steady state (SPGR), MR angiography, and three-dimensional (3-D) imaging reconstructed from the data of SPGR MR imaging by the surface rendering method at a workstation.
  
  
  RESULTS
  In all patients, the preoperative SPGR MR images demonstrated that the causative vessels compressed or were in contact with the root exit or root entry zone (REZ) of the facial or trigeminal nerve. These causative vessels were identified by inspection of the MR angiographic and 3-D images. The 3-D images provided clear information as to the anatomic relationship between the causative vessels and the REZ of these nerves. These findings were corroborated by the intraoperative findings. The symptoms were completely relieved after surgery in 18 of the patients with hemifacial spasm and in all six patients with trigeminal neuralgia. In all patients, sufficient decompression was depicted on the postoperative SPGR MR images at the causative vessels and the REZ of the nerve.
  
  
  CONCLUSIONS
  SPGR MR images, MR angiography, and 3-D images are useful for the identification of the causative vessels in patients with hemifacial spasm or trigeminal neuralgia. The 3-D images are particularly useful for the simulation planning of the operative procedure.
authors.affiliation: Department of Neurological Surgery, Ehime University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kumon
authors.forename: S
authors.initials: S
authors.lastname: Sakaki
authors.forename: K
authors.initials: K
authors.lastname: Kohno
authors.forename: S
authors.initials: S
authors.lastname: Ohta
authors.forename: S
authors.initials: S
authors.lastname: Ohue
authors.forename: H
authors.initials: H
authors.lastname: Miki
mesh_terms: D000328:Adult; D000368:Aged; D002531:Cerebellum / Q000098:blood supply / Q000000981:diagnostic imaging; D005152:Facial Muscles / Q000098:blood supply* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011859:Radiography; D013035:Spasm / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014277:Trigeminal Neuralgia / Q000000981:diagnostic imaging / Q000473:pathology*