Hepatic lesion detection and characterization: value of nonenhanced MR imaging, superparamagnetic iron oxide-enhanced MR imaging, and spiral CT-ROC analysis.
OBJECTIVE
To determine the accuracy for detection and characterization of focal hepatic lesions of nonenhanced, superparamagnetic iron oxide (SPIO)-enhanced, or a combination of nonenhanced and SPIO-enhanced MR imaging and contrast-enhanced spiral computed tomography (CT).


METHODS
Spiral CT and T2-weighted SPIO-enhanced (ferucarbotran-enhanced) MR imaging were performed in 35 patients within 2 weeks before surgery for malignant hepatic lesions. Only malignant lesions with histopathologic proof were considered. A total of 875 images with and 800 images without focal lesions were presented to five readers, who were asked to assess the presence and characterization of lesions by using a five-point confidence scale. Receiver operating characteristic analysis was performed.


RESULTS
Nonenhanced and SPIO-enhanced images together and SPIO-enhanced images alone yielded the best performance for lesion detection. No differences were found among all imaging techniques with regard to lesion characterization (benign vs malignant). The combined approach resulted in larger area under the ROC curve (A(z) = 0.9062) and accuracy (85.3%) (P < 0.02), as compared with SPIO-enhanced MR imaging (A(z) = 0.8667; accuracy, 73.1%).


CONCLUSIONS
SPIO-enhanced T2-weighted MR imaging was more accurate than nonenhanced T1-weighted and T2-weighted MR imaging and contrast-enhanced spiral CT for the detection of focal hepatic lesions. The combined analysis of nonenhanced and SPIO-enhanced images was more accurate in the characterization of focal hepatic lesions than was review of SPIO-enhanced images alone.
Reimer
P
P
Department of Radiology, Städtisches Klinikum Karlsruhe, Moltkestrasse 90, D-76133 Karlsruhe, Germany. reimerp@uni-muenster.de
Jähnke
N
N
Fiebich
M
M
Schima
W
W
Deckers
F
F
Marx
C
C
Holzknecht
N
N
Saini
S
S
D003287:Contrast Media; D003911:Dextrans; D005260:Female; D052203:Ferrosoferric Oxide; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007501:Iron; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D010087:Oxides; D012372:ROC Curve; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide