J Korean Radiol Soc.  1994 Jun;30(6):981-986.

MR Findings of Cystic Acoustic Neurinomas

• Lim SJ
• Yoon Y
• Ryu KN
• Choi WS
• Song MJ

Abstract

PURPOSE
The purpose of this study was to evaluate the spectrum of MR characteristics of cystic acoustic neurinomas and to correlate with pathologic findings.
MATERIALS AND METHODS
We retrospectively reviewed the MR findings of 12 patients with cystic acoustic neurinomas. The signal intensity and enhancement pattern of the cystic components as well as the location relative to the tumors were analyzed.
RESULTS
A total of 30 cysts were found in 15 acoustic neurinomas;28 were intratumoral cysts and the remaining two were extratumoral cysts. The signal intensity of all 28 intratumoral cysts was higher than that of CSF on Tl-weighted images, and isointense to CSF on T2-weighted images, while the signal intensity of the two extratumoral cysts was same as CSF on both Tl-weighted and T2-weighted images. Rim enhancement was seen in 27 of 28 intratumoral cysts but in none of the two extratumoral cysts.
CONCLUSION
We concluded that intratumoral cyst was due to tumoral necrosis, hemorrhage or degenerative change and extratumoral cyst due to secondary arachnoid cyst formation.

MeSH Terms

Acoustics*
Arachnoid
Hemorrhage
Humans
Necrosis
Neuroma, Acoustic*
Retrospective Studies