Contrast-enhanced CISS MRI of vestibular schwannomas: phantom and clinical studies.

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.

• 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)

Chemical References

• Contrast Media
• Gadolinium DTPA

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)