MR Imaging of Renal Masses Interpreted on CT to Be Suspicious

Abstract

Renal masses that are interpreted as suspicious on CT may lack MR enhancement because of hemorrhage effects; heterogeneity of their T2 appearance is thus critical in differentiating malignancy from benign disease. Odds-ratio calculations give an adjusted estimate of a 3.36-fold increase (95% confidence interval, 1.8-6.27) in the likelihood of malignancy when masses are heterogeneous on T2-weighted images and a 29-fold increase (95% confidence interval, 3.67-241.8) for predicting malignancy when enhancement is present.

Contrast-enhanced ultrasound (CEUS) of cystic and solid renal lesions: a review

“…Although color and power Doppler may be useful to evaluate the vascular pattern of a suspected pseudotumor, both techniques have poor sensitivity in patients who are obese or have difficulty in breath holding [46,47]. CECT or MRI are often used to characterize a possible renal pseudotumor, due to their added value in vascular characterization [48,49].…”

2-Deoxy-2-[F-18]fluoro-D-glucose-Positron Emission Tomography in Characterization of Solid Renal Masses

“…However, these anatomic imaging modalities frequently may not be able to differentiate benign from malignant solid renal tumors [8]. MRI has shown promising results for the evaluation of renal lesions, especially in cases in which USG and CT results are not definitive [9]. However, MRI has wide variability in its accuracy, depending on the degree of enhancement threshold.…”

“…The majority of solid renal masses can be classified as benign or malignant using well-established criteria of contrast enhancement on CT and MRI. However, renal masses with 10Y19 Hounsefield units are classified as Fintermediate_ on CT [8,9]. In addition, CT attenuation measurement in small lesions is also problematic due to partial volume averaging [20].…”

Evaluation and management of kidney lesions: comparison of 16-MDCT and magnetic resonance imaging

“…For pre-contrast imaging, T2, T2 FS, T1 in IN and OUT Phase sequences are acquired. T1-weighted post-contrast sequences are very similar to the CT sequences above but intermediate sequences (e.g., early and late arterial, and at least three late phases) are also acquired, which provide the radiologist with further information [7]. The advantages of MRI lie in its higher sensitivity in the depiction of small focal lesions (< 1 cm) and in the fact that more sequences can be acquired without any problems of radiation exposure [8].…”