Greater Stone Density Predicts SWL Failure
Eur Urol. 2007;51:1688-1694
High renal-stone density and elevated BMI decrease the likelihood of stone disintegration with shock wave lithotripsy (SWL), Egyptian researchers conclude.
Ahmed R. El-Nahas, MD, and his colleagues at the Urology and
Stone density greater than 1000 Hounsfield units was associated with an eight times increased likelihood of failure to disintegrate. The mean BMI was 32.5 kg/m2 for 15 patients in the failure-to-disintegrate group compared with 28.1 kg/m2 in the 105 successful cases. Each1 kg/m2 increase in BMI was associated with a 12% in-creased likelihood of failure to disintegrate. In addition, obese patients (BMI 30 kg/m2 or higher) were 3.4 times more likely than non-obese patients to require more than three SWL sessions to achieve stone fragmentation.