title: Contrast-enhanced CISS MRI of vestibular schwannomas: phantom and clinical studies.
abstract: OBJECTIVE
  The purpose of this work was to assess the changes of signal intensity on constructive interference in steady state (CISS) 3D Fourier transformation (3DFT) MRI after administration of Gd-DTPA and to evaluate the efficacy of contrast-enhanced CISS-3DFT MRI to depict the seventh and eighth cranial nerves affected by vestibular schwannomas.
  
  
  METHODS
  All scans were carried out on a 1.5 T MR unit. First, an experimental study was conducted to evaluate the changes in signal intensity of the CISS-3DFT sequence in relation to the concentration of contrast medium. Second, nine consecutive patients with 11 vestibular schwannomas underwent CISS-3DFT imaging before and after contrast agent administration. Signal intensities of the tumors and nerves were measured and compared between the pre- and postcontrast images. Visualization of the facial and cochlear nerves was rated on pre- and postcontrast CISS imaging independently.
  
  
  RESULTS
  On the phantom study, the CISS-3DFT sequence showed a constant increase in signal intensity as the concentration of Gd-DTPA increased. The contrast between the nerves and tumors significantly increased after contrast agent administration (from 0.1 to 9.0 as mean contrast-to-noise ratio). The ability to depict the nerves was also significantly higher for postcontrast CISS-3DFT imaging than for precontrast.
  
  
  CONCLUSIONS
  Although the CISS-3DFT sequence offers similar contrast as other heavily T2-weighted sequences, the signal intensity of contrast-enhanced tumors increased on CISS-3DFT imaging. Contrast-enhanced CISS imaging was valuable for evaluating the seventh and eighth cranial nerves affected by vestibular schwannomas.
authors: Department of Radiology, Kumamoto University School of Medicine, Japan.
authors: Y
authors: Y
authors: Shigematsu
authors: Y
authors: Y
authors: Korogi
authors: T
authors: T
authors: Hirai
authors: T
authors: T
authors: Okuda
authors: I
authors: I
authors: Ikushima
authors: T
authors: T
authors: Sugahara
authors: L
authors: L
authors: Liang
authors: M
authors: M
authors: Takahashi
mesh_terms: D000328:Adult; D003287:Contrast Media; D003390:Cranial Nerve Neoplasms / Q000175:diagnosis*; D005154:Facial Nerve / Q000473:pathology; D005155:Facial Nerve Diseases / Q000175:diagnosis*; D005260:Female; D005583:Fourier Analysis; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000175:diagnosis*; D009464:Neuroma, Acoustic / Q000175:diagnosis*; D019047:Phantoms, Imaging / Q000706:statistics & numerical data; D011446:Prospective Studies; D000159:Vestibulocochlear Nerve / Q000473:pathology
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA