Applicazione dell'elastosonografia nel follow up del paziente con uropatia malformativa

Virtual Touch Tissue Quantification: a new approach to assess renal stiffness in children with vesicoureteral reflux Vesicoureteral reflux (VUR) is the backup of urine from the bladder into the ureteres frequently associated with congenital or acquired renal damage. The preferred method for visualizing functioning renal parenchyma is 99Tc-DMSA renal scintigraphy. Virtual Touch tissue quantification is an implementation of ultrasound Acoustic Radiation Force Impulse (ARFI) imaging that provides numerical measurements (wave velocity values) of tissue stiffness and the degree of renal fibrosis. The aim of the present preliminary study was to assess renal fibrosis by Virtual Touch tissue quantification in a group of 28 children (17 males, 11 females; age 12 ± 3 years) with primary (n° 18) or secondary VUR (n°10) and history of urinary tract infection. The data obtained in our children were compared with data obtained on 16 healthy children matched for sex and age. The wave velocity values of pathological kidneys were significantly more elevated than values of non affected kidneys (176±45 versus 94±2; p<0.001). Is very interesting that in cases of unilateral VUR we found wave velocity values, either in the affected kidney (152±40; p<0.001) or in the controlateral ‘healthy’ kidney (124±16; p<0.05), higher than values in healthy controls. Moreover we found a significant correlation between the elastosonographic measures and the plasmatic cystatin C (r=0,434; P< 0.05). The present preliminary study suggests that Virtual Touch tissue quantification might be an innovative and promising technique to assess tissue stiffness and fibrosis in children with VUR and chronic renal disease. A long-term follow-up might aid to monitor the evolution of renal damage.