Two-dimensional shear wave elastography of the perirenal fat: Can sticky fat be predicted?

Abstract

To evaluate whether two-dimensional (2D) shear wave elastography (SWE) can predict the presence of perirenal sticky fat (PSF) by showing increased perirenal fat stiffness. We prospectively enrolled 28 patients with 31 renal tumors and 10 donor cases. Conventional renal ultrasound (US) and 2D-SWE examination of the perirenal fat were performed. Patient age, gender, body mass index (BMI), largest mass size, PF shear wave velocity (SWV) on both sides were recorded. During surgery, presence of PSF and perirenal fat dissection time (PFDT) were recorded. Twenty three renal masses were malignant and eight were benign. There were 13 clear cell carcinomas and 10 nonclear cell carcinomas. Eight patients had PSF. Mean PFDT was 13 minutes. PFDT and BMI were significantly increased in the PSF group (p < .05). No statistically significant differences were found in SWVs in patients with and without PSF. There were no significant differences with regard to SWVs between donor cases and patients, tumor side and nontumor side, benign masses and malignant masses, clear cell and nonclear cell tumors. No significant correlations were detected between SWVs and PFDT, mass size, Fuhrman grade and BMI (p > .05). 2D-SWE cannot detect PSF.