Three Dimensional Volume Rendering Virtual Endoscopy of the Ossicles Using a Multi-Row Detector CT: Applications and Limitations.
10.3348/jkrs.2005.53.2.85
- Author:
Su Yeon KIM
1
;
Sun Seob CHOI
;
Myung Jin KANG
;
Tae Beom SHIN
;
Ki Nam LEE
;
Myung Koo KANG
Author Information
1. Department of Diagnostic Radiology, College of Medicine, Dong-A University, Korea. sschoi317@yahoo.co.kr
- Publication Type:Original Article
- Keywords:
Temporal bone, CT;
Computed tomography (CT), three-dimensional;
Computed tomography (CT), volume rendering
- MeSH:
Ear;
Endoscopy*;
Hearing;
Humans;
Incus;
Malleus;
Stapes;
Temporal Bone;
Tomography, X-Ray Computed
- From:Journal of the Korean Radiological Society
2005;53(2):85-90
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: This study was conducted to know the applications and limitations of three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT. MATERIALS AND METHODS: This study examined 25 patients who underwent temporal bone CT using a 16-row detector CT as a result of hearing problems or trauma. The axial CT scan of the temporal bone was performed with a 0.6 mm collimation, and a reconstruction was carried out with a U70u Sharp of kernel value, a 1 mm thickness and 0.5-1.0 mm increments. After observing the ossicles in the axial and coronal images, virtual endoscopy was performed using a three dimensional volume rendering technique with a threshold value of -500 HU. The intra-operative otoendoscopy was performed in 12 ears, and was compared with the virtual endoscopy findings. RESULTS: Virtual endoscopy of the 29 ears without hearing problems demonstrated hypoplastic or an incomplete depiction of the stapes superstructures in 25 ears and a normal depiction in 4 ears. Virtual endoscopy of 21 ears with hearing problems demonstrated no ossicles in 1 ear, no malleus in 3 ears, a malleoincudal subluxation in 6 ears, a dysplastic incus in 5 ears, an incudostapedial subluxation in 9 ears, dysplastic stapes in 2 ears, a hypoplastic or incomplete depiction of the stapes in 16 ears and no stapes in 1 ear. In contrast to the intra-operative otoendoscopy, 8 out of 12 ears showed a hypoplastic or deformed stapes in the virtual endoscopy. CONCLUSION: Volume rendering virtual endoscopy using a multi-row detector CT is an excellent method for evaluation the ossicles in three dimension, even though the partial volume effect for the stapes superstructures needs to be considered.
