Reliability of ADC values in recognition of renal changes produced by extracorporeal shock wave lithotripsy (ESWL)

Abstract

Objectives: To evaluate the reliability of diffusion-weighted imaging (DWI) in evaluating kidney changes after extracorporeal shock wave lithotripsy (ESWL) treatment for kidney stones. Patients and methods: This prospective study included 28 patients who subjected to ESWL treatment for renal stones. Color Doppler ultrasonography (CDUS) and DWI were achieved before and within one day after ESWL. Follow up DWI also performed 2 weeks after ESWL. DWI was performed with b factors of 0, 500 and 1000 s/mm2 at 1.5 T MRI. For each patient, the Resistive index (RI) and ADC values were calculated for both the affected and contralateral kidneys. Results: The ADC values of the treated kidneys were lower in all three poles of the kidney compared with ADC values done before ESWL and in comparison with the contra lateral un-treated kidney. The RI showed no significant difference in the three poles of treated and untreated kidneys before and after with ESWL (p > 0.05). Conclusion: DWI is a reliable method in detecting renal changes after ESWL treatment that can give prediction about kidney changes produced by shock waves. Keywords: Lithotripsy, Kidney, Stones, DWI