Usefulness of Enteral Contrast Media in MR Evaluation of Pelvic Mass

ABSTRACT

PURPOSE: To assess the value of enteral contrast media for the evaluation of pelvic masses by MR imaging. MATERIALS AND METHODS: Between April and July 1998, 16 women with pelvic masses were examined by MRI. The origin of the lesion was the ovary in twelve cases, the uterus in three, and the sigmoid in one. Using a 1.5T scanner(Magnetom Vision, Siemens), T1-weighted axial spin echo(SE), T2-weighted turbo spin echo(TSE), two-dimensional fast low-angle shot(FLASH 2D), and half-Fourier TSE(HASTE) images were obtained in all patients after the administration of Magnevist Enteral (Shering, Berlin, Germany). In each MR imaging sequence, distinction between the lesion and adjacent bowel (1, not distinguished; 2, partly distinguished; 3, clearly distinguished), artifact (0, absent; 1, mild; 2, severe), image quality (1, poor; 2, fair; 3, good), were compared before and after the use of enteral contrast media. Changes in MRI impression after the use of enteral contrast media were also evaluated. Two radiologists reached a consensus after reviewing the images. Statistical significance was determined by Wilcoxon's signed ranked test. RESULTS: For distinguishing lesions, SE T1WI and FLASH 2D with enteral contrast media were significantly superior to SE T1WI without enteral contrast media (p<0.05). With regard to image quality, FLASH 2D and HASTE, both with enteral contrast media, were significantly superior to SE T1WI and TSE T2WI, respectively, both without enteral contrast media (p<0.05). Artefacts were more frequently found after the application of enteral contrast media in conventional sequences but were not present in breathhold sequences. In two patients, MRI impression changed after the appilication of enteral contrast media. CONCLUSION: In a limited number of cases, enteral contrast media improved lesion detection, image quality and diagnostic accuracy when breathhold fast MR imaging was applied.