Re: Small solid renal masses: Characterization by diffusion-weighted MRI at 3 T

摘要

Sir -We read with great interest the recent article by Agnello et al.1 dealing with the appearance of small solid renal lesions (<3 cm) on diffusion-weighted magnetic resonance imaging and determining whether apparent diffusion coefficient (ADC) measurements may help to differentiate benign from malignant small solid renal masses. The authors reported that small solid renal masses are hyperintense at high b-values and have different ADC values. In our opinion, some points in this article are not sufficiently clear. In their study, Agnello et al.1 reported that they used different sizes of the regions of interest (ROIs), which were 3.8 ± 0.6 cm2, and 1.1 ± 0.4 cm2 for lesions and normal renal parenchyma at the level of the cortico-medullary junction, respectively. It has been affirmed that ROI size might affect the accuracy of ADC measurements due to variety of the internal structure and signal intensity of the tissue.