[Imaging tumor extension of renal cell carcinomas with magnetic resonance tomography. Improved tumor-tissue contrast with Gd-DTPA-assisted spin-echo sequences and simultaneous fat suppression].
OBJECTIVE
To evaluate the use of contrast-enhanced T1-weighted images with fat suppression (T1FS) to improve the contrast-to-noise ratio of renal cancer and renal parenchyma as well as perirenal fat.


METHODS
25 patients with histologically proven unilateral renal cancer after nephrectomy were examined before surgery. In addition to plane and contrast-enhanced T1-weighted as well as T2-weighted spin-echo images, all patients had T1 FS immediately after administration of Gd-DTPA in two planes. The contrast-to-noise ratio was calculated using circular regions-of-interest which outlined the tumor, the renal parenchyma, pyelon, and the perirenal fat.


RESULTS
T1 FS significantly improved the contrast-to-noise ratio of renal cancer and renal parenchyma compared to all conventional spinecho sequences (p < 0.001; Wilcoxon-Test). Compared to contrast-enhanced T1-weighted images without fat-suppression T1 FS yielded a higher CNR of the tumor, the perirenal fat and the pyelon. Another advantage was the absence of the chemical-shift artifact which is mostly pronounced in T2-weighted images and a reduced number of observed artifacts due to breathing.


CONCLUSIONS
T1 FS should replace conventional contrast-enhanced T1-weighted spin-echo images in the work-up of renal cancer using MRI.
Venz
S
S
Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität, Berlin.
Hierholzer
J
J
Keske
U
U
Friedrichs
R
R
Schröder
R
R
Siewert
C
C
Hosten
N
N
Felix
R
R
D000328:Adult; D000368:Aged; D016477:Artifacts; D002292:Carcinoma, Renal Cell / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement; D007668:Kidney / Q000473:pathology; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012680:Sensitivity and Specificity
D003287:Contrast Media; D019786:Gadolinium DTPA
Darstellung der Tumorausdehnung von Nierenzellkarzinomen mit der Magnetresonanztomographie. Verbesserung des Tumor-Gewebekontrastes mittels Gd-DTPA unterstützter Spin-Echo-Sequenzen und gleichzeitiger Fettsättigung.