Value Of Diffusion – Weighted And Contrast Enhanced Magnetic Resonance Imaging In Differentiation Of Renal Masses

Renal masses are being discovered with increasing frequency dueto the large number of cross-sectional studies being performed in clinicalpractice. Accurate characterization of renal masses is essential to ensureappropriate case management and to assist in staging and prognosis (41).Accurate characterization of complex renal lesions is based primarily onthe presence or absence of enhancement on contrast material enhancedMagnetic Resonance (MR) images. When such enhancement is present, itgenerally indicates a diagnosis of renal cell carcinoma (RCC) (excludingbenign masses like angiomyolipomas and oncocytomas). With MRimaging, enhancement can be assessed by measuring signal intensitychanges or evaluated visually with or without image subtraction (91).However, in view of recently reported concerns regarding thedevelopment of nephrogenic systemic fibrosis in patients with renalinsufficiency who undergo contrast-enhanced MR imaging, there isincreasing interest in assessing nonenhanced imaging modalities thatmight be useful for characterizing renal lesions (33).The aim of this study is to evaluate the role of contrast enhanced magnetic resonance imaging and the usefulness of diffusion weighted magnetic resonance imaging in differentiating benign from malignant renal masses and to assess the diffusion characteristics as well as apparent diffusion coefficient (ADC) values of different renal masses.In conclusion, breath-hold DW imaging could be easily added to a routine renal MR imaging protocol, is an accurate method for renal lesion characterization, and can yield useful information additional to that acquired with contrast-enhanced MR imaging. We recommend using high b values for better results.