Abstract | PURPOSE: 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. METHOD: 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. CONCLUSION: 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.
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Authors | Y Shigematsu, Y Korogi, T Hirai, T Okuda, I Ikushima, T Sugahara, L Liang, M Takahashi |
Journal | Journal of computer assisted tomography
(J Comput Assist Tomogr)
1999 Mar-Apr
Vol. 23
Issue 2
Pg. 224-31
ISSN: 0363-8715 [Print] United States |
PMID | 10096329
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Contrast Media
- Gadolinium DTPA
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Topics |
- Adult
- Contrast Media
- Cranial Nerve Neoplasms
(diagnosis)
- Facial Nerve
(pathology)
- Facial Nerve Diseases
(diagnosis)
- Female
- Fourier Analysis
- Gadolinium DTPA
- Humans
- Magnetic Resonance Imaging
(methods, statistics & numerical data)
- Male
- Middle Aged
- Neurilemmoma
(diagnosis)
- Neuroma, Acoustic
(diagnosis)
- Phantoms, Imaging
(statistics & numerical data)
- Prospective Studies
- Vestibulocochlear Nerve
(pathology)
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