The role of plain radiography in predicting renal stone fragmentation by shockwave lithotripsy in the era of noncontrast multidetector computed tomography.

PURPOSE: The objective of this study is to determine if plain radiography has a role in prediction of stone fragmentation by shockwave lithotripsy (SWL). PATIENTS AND METHODS: Our study included 106 patients undergoing SWL for renal stones. Based on plain radiography criteria, stones were classified according to density, homogeneity, and outline. We compared the success of SWL in fragmentation of stones with a density equal to or less than bone, nonhomogeneous stones, and stones with irregular outline to its success in stones with a density more than bone, homogeneous stones, and stones with smooth outline. RESULTS: In plain radiography, stone density equal to or less than bone, nonhomogeneous stones, and stones with irregular outline showed successful SWL fragmentation in 88.8%, 91.2%, and 90.6%, respectively. Stones with a density more than bone, homogeneous stones, and stones with smooth outline showed successful SWL fragmentation in 52.9%, 52.6%, and 57.1%, respectively. CT attenuation value was significantly less in stones successfully fragmented by SWL compared with nonfragmented stone (649±169 and 1465±256, respectively). In homogeneous stones with smooth outline having a density more than bone, we found a significantly lower CT attenuation in patients with successful stone fragmentation by SWL compared with those with failed stone fragmentation (690.9±171 and 1462±212, respectively). CONCLUSION: In relatively large solitary renal pelvic stones, plain radiography can predict the success of stone fragmentation by SWL. Nonhomogeneous stones with irregular outline and a density equal to or less than bone are expected to be successfully fragmented by SWL. Noncontrast CT is only needed, to predict success of SWL, in cases of homogeneous stones with smooth outline and density more than bone.

Stenting versus non-stenting after non-complicated ureteroscopic manipulation of stones in bilharzial ureters.

BACKGROUND: Stents were used routinely after ureteroscopy to prevent postoperative ureteral obstruction. However, because of the recognized complications of stents, non-stenting is the new trend after uncomplicated ureteroscopy. The wall of the bilharzial ureter is characteristically thick and may be calcified. The aim of this study is to see if the non-stenting trend could be applied to ureteroscopic manipulation of stones in bilharzial ureters. PATIENTS AND METHODS: In this prospective study, 56 patients, with evidence of bilharzial lesions in the urinary tract, undergoing ureteroscopy for distal ureteral stones were included. After successful uncomplicated stone fragmentation and extraction, patients were randomized into two groups. Group A includes 28 patients in whom double J 6-Fr polyurethane stents were placed for 3 weeks. Group B includes 28 non-stented patients. Postoperative fever, loin pain, lower urinary tract symptoms and change in the degree of hydronephrosis were reported. RESULTS: There was no significant difference in the mean age of patients and stone size in both groups. The mean operative time was 43 +/- 14 min in group A and 38 +/- 11 in group B. There was no significant difference in the mean loin pain score, in the first postoperative 48 h, in both groups (4.4 +/- 0.8 in group A and 4.9 +/- 0.5 in group B). Patients in group A had, significantly, more flank pain with voiding (P < 0.01), voiding pain (P = 0.04), frequency (P = 0.01) and urgency (P = 0.04). Radiologic follow-up was available for 24 patients in group A and 23 patients in group B at the 3-month visit. Hydronephrosis had improved in all patients, in both groups, with no evidence of ureteral stricture. CONCLUSION: Routine placement of stents after uncomplicated ureteroscopy for distal ureteral stones is unnecessary in bilharzial ureters. Moreover, it might be unadvisable because lower urinary tract symptoms and voiding loin pain are more in patients with ureteral stents and hydronephrosis is equally improved in stented and non-stented patients.