Fusion of MRI and sonography image for breast cancer evaluation using real-time virtual sonography with magnetic navigation: first experience.
OBJECTIVE
We recently developed a real-time virtual sonography (RVS) system that enables simultaneous display of both sonography and magnetic resonance imaging (MRI) cutaway images of the same site in real time. The aim of this study was to evaluate the role of RVS in the management of enhancing lesions visualized with MRI.


METHODS
Between June 2006 and April 2007, 65 patients underwent MRI for staging of known breast cancer at our hospital. All patients were examined using mammography, sonography, MRI and RVS before surgical resection. Results were correlated with histopathologic findings. MRI was obtained on a 1.5 T imager, with the patient in the supine position using a flexible body surface coil. Detection rate was determined for index tumors and incidental enhancing lesions (IELs), with or without RVS.


RESULTS
Overall sensitivity for detecting index tumors was 85% (55/65) for mammography, 91% (59/65) for sonography, 97% (63/65) for MRI and 98% (64/65) for RVS. Notably, in one instance in which the cancer was not seen on MRI, RVS detected it with the supplementation of sonography. IELs were found in 26% (17/65) of the patients. Of 23 IELs that were detected by MRI, 30% (7/23) of IELs could be identified on repeated sonography alone, but 83% (19/23) of them were identified using the RVS system (P = 0.001). The RVS system was able to correctly project enhanced MRI information onto a body surface, as we checked sonography form images.


CONCLUSIONS
Our results suggest that the RVS system can identify enhancing breast lesions with excellent accuracy.
Nakano
Shogo
S
Division of Breast and Endocrine Surgery, Department of Surgery, Aichi Medical University, 21 Nagakute-cho, Aichi-gun, Aichi 480-1195, Japan. snakano1@aichi-med-u.ac.jp
Yoshida
Miwa
M
Fujii
Kimihito
K
Yorozuya
Kyoko
K
Mouri
Yukako
Y
Kousaka
Junko
J
Fukutomi
Takashi
T
Kimura
Junko
J
Ishiguchi
Tsuneo
T
Ohno
Kazuko
K
Mizumoto
Takao
T
Harao
Michiko
M
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis*; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008327:Mammography; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016217:Ultrasonography, Mammary; D014584:User-Computer Interface