OBJECTIVE: To compare the usefulness of unenhanced spiral CT (UCT) with that of excretory urography (EU) in patients with acute flank pain. MATERIALS AND METHODS: Thirty patients presenting with acute flank pain under-went both UCT and EU. Both techniques were used to determine the presence, size, and location of urinary stone, and the presence or absence of secondary signs was also evaluated. The existence of ureteral stone was confirmed by its removal or spontaneous passage during follow-up. The absence of a stone was determined on the basis of the clinical and radiological evidence. RESULTS: Twenty-one of the 30 patients had one or more ureteral stones and nine had no stone. CT depicted 22 of 23 calculi in the 21 patients with a stone, and no calculus in all nine without a stone. The sensitivity and specificity of UCT were 96% and 100%, respectively. EU disclosed 14 calculi in the 21 patients with a stone and no calculus in eight of the nine without a stone. UCT and EU demon-strated secondary signs of ureterolithiasis in 15 and 17 patients, respectively. CONCLUSION: For the evaluation of patients with acute flank pain, UCT is an excellent modality with high sensitivity and specificity. In near future it may replace EU.
Adult ; Colic/*radiography ; Female ; Human ; Male ; Middle Age ; Sensitivity and Specificity ; Tomography, X-Ray Computed/*methods ; Ureteral Calculi/*radiography ; Ureteral Diseases/*radiography ; *Urography

Purpose: The aim of this study was to compare the efficacy, safety and compliance of ureteroscopic stone removal (URS) patients who were treated with extracorporeal shock wave lithotripsy (ESWL) for large (>10mm) proximal ureteral stones. Materials and Methods: We reviewed 123 patients who were treated for upper ureteral stones (>10mm) between January 2000 and March 2005. URS and ESWL were performed in 51 and 72 patients, respectively. Success was defined as the patients achieving a stone-free status on radiography at 1 month after treatment. We analyzed the success rates of stone removal, the reasons for failure and the complication rates of each procedure. Results: The overall success rate of URS was 90.2%. For the ESWL treatments, the overall success rates after the first, second, third and more sessions were 47.2%, 61.1%, 76.4% and 81.9%, respectively. Notably, the stone free rate of the URS group was better than that of the 1st, 2nd and 3rd session ESWL group (p<0.05). The complication rate of URS was 24.0% and that of ESWL was 22.2%; the difference was not statistically significant (p<0.05). Conclusions: In this study, URS achieved an excellent stone free rate and a similar complication rate to that of ESWL for treating large (>10mm) upper ureteral calculi. Thus, this procedure should be considered as first line therapy for large (>10mm) upper ureteral stones. In addition, for the proper selection of patients for ESWL and URS, analysis of the cost effectiveness, compliance and recurrence rates of the two groups should be done in the future.
Compliance ; Cost-Benefit Analysis ; Humans ; Lithotripsy* ; Radiography ; Recurrence ; Shock* ; Ureter* ; Ureteral Calculi ; Ureteroscopes

PURPOSE: Central lucency of pelvic phleboliths is frequently observed on plain pelvic radiographs. When it is also present on noncontrast helical CT images, pelvic phleboliths may be easily diagnosed, with no suspicion of distal ureteral calculi. The objective of this study was to determine the frequency with which this phenome-non is seen on plain radiographs and noncontrast helical CT images. MATERIALS AND METHODS: During a recent two-year period we identified 70 patients with renal colic who under-went both abdomino-pelvic radiography and noncontrast helical CT scanning. Radiographs were obtained at 70 -85 kVp and 30 -40 mA; CT scans were preformed within one month of plain radiography with parameters of 120 kVp, 200 -220 mA, 5-mm collimation, and pitch of 1 -1.6, and using soft tissue and bone window settings. With regared to the central lucency of pelvic phleboliths, as seen on both on radiographs and CT im-ages, two experienced radiologists reached a consensus. RESULTS: Among the 70 patients, a total of 150 pelvic phleboliths was found. In all cases except one, pelvic radi-ography and noncontrast helical CT revealed the same number of phleboliths. The exception was a case in which one of two phleboliths demonstrated by CT was not seen on radiographs. Pelvic radiography revealed central lucency in 95 of these 150 phleboliths (63%), but noncontrast helical CT failed to depict a hypodense center in any phlebolith. CONCLUSION: Central lucency of pelvic phleboliths, as frequently seen on plain pelvic radiographs, was not revealed by routine noncontrast helical CT in any patient.The presence or absence of central lucency on these CT images cannot, therefore, be used to differentiate phleboliths from distal ureteral calculi.
Consensus ; Humans ; Radiography ; Renal Colic ; Tomography, Spiral Computed* ; Tomography, X-Ray Computed ; Ureteral Calculi

PURPOSE: To assess the potential of dual-energy computed tomography (DECT) to identify urinary stone components, particularly uric acid and calcium oxalate monohydrate, which are unsuitable for extracorporeal shock wave lithotripsy (ESWL). MATERIALS AND METHODS: This clinical study included 246 patients who underwent removal of urinary stones and an analysis of stone components between November 2009 and August 2013. All patients received preoperative DECT using two energy values (80 kVp and 140 kVp). Hounsfield units (HU) were measured and matched to the stone component. RESULTS: Significant differences in HU values were observed between uric acid and nonuric acid stones at the 80 and 140 kVp energy values (p<0.001). All uric acid stones were red on color-coded DECT images, whereas 96.3% of the nonuric acid stones were blue. Patients with calcium oxalate stones were divided into two groups according to the amount of monohydrate (calcium oxalate monohydrate group: monohydrate> or =90%, calcium oxalate dihydrate group: monohydrate<90%). Significant differences in HU values were detected between the two groups at both energy values (p<0.001). CONCLUSIONS: DECT improved the characterization of urinary stone components and was a useful method for identifying uric acid and calcium oxalate monohydrate stones, which are unsuitable for ESWL.
Adult ; Aged ; Calcium Oxalate/analysis ; Female ; Humans ; Kidney Calculi/*chemistry/*radiography/therapy ; *Lithotripsy ; Male ; Middle Aged ; Patient Selection ; Radiography, Dual-Energy Scanned Projection ; Tomography, X-Ray Computed/*methods ; Ureteral Calculi/*chemistry/*radiography/therapy ; Uric Acid/analysis

PURPOSE: To report the outcome of laparoscopic pyelo- and ureterolithotomies with the aid of flexible nephroscopy. MATERIALS AND METHODS: A retrospective analysis was performed in 71 patients with complex renal stones or large and impacted proximal ureteral stones. Patients underwent laparoscopic pyelo- or ureterolithotomies with or without the removal of small residual stones by use of flexible nephroscopy between July 2005 and July 2010. Operative success was defined as no residual stones in the intravenous pyelogram at 12 weeks postoperatively. Perioperative results and surgical outcomes were analyzed. RESULTS: The patients' mean age was 54.7+/-13.7 years, and 53 males (74.6%) and 18 females (25.4%) were included. The mean maximal stone size was 19.4+/-9.4 mm. A total of 47 cases were complex renal stones and 24 cases were impacted ureteral stones. Mean operative time was 139.0+/-63.7 minutes. Stones were completely removed in 61 cases (85.9%), and no further ancillary treatment was needed for clinically insignificant residual fragments in 7 cases (9.9%). For complex renal stones, the complete stone-free rate and clinically significant stone-free rate were 80.9% and 93.6%, respectively. Multivariate analysis showed that the use of flexible nephroscopy for complex renal stones can reduce the risk of residual stones. A major complication occurred in one case, in which open conversion was performed. CONCLUSIONS: Laparoscopic stone surgery is a safe and minimally invasive procedure with a high success rate, especially with the aid of flexible nephroscopy, and is not associated with procedure-specific complications.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Kidney Calculi/pathology/radiography/*surgery ; Laparoscopy/methods ; Male ; Middle Aged ; Nephrostomy, Percutaneous/*methods ; Retrospective Studies ; Treatment Outcome ; Ureteral Calculi/pathology/radiography/*surgery ; Young Adult

PURPOSE: The aim of our study was to evaluate the association of several factors with spontaneous stone expulsion, including ureteral stone characteristics (size, location, hydronephrosis, perinephric stranding), types of medications prescribed (alpha-blocker, low-dose steroid), and other possible demographic and health-history factors (gender, age, serum creatinine, underlying diabetes mellitus [DM], and hypertension). MATERIALS AND METHODS: A total of 366 patients with ureteral stones were enrolled. All patients underwent watchful waiting without any invasive procedures. Initial diagnoses of ureteral stones were confirmed by computed tomography scans, which were taken at approximately 1-month intervals to check for stone expulsion. Univariate and multivariate analyses were conducted to identify significant factors that contributed to stone expulsion. RESULTS: Among 366 patients, 335 patients (91.5%) experienced spontaneous stone passage during a mean follow-up period of 2.95+/-2.62 weeks. The patients were divided into two groups depending on the success of spontaneous stone passage. Univariate analyses revealed that stone location (p=0.003), stone size (p=0.021), and underlying DM (p<0.001) were significant predictors of stone passage. Multivariate analyses confirmed that stone size (p=0.010), stone location (p=0.008), and underlying DM (p=0.003) were independent predictive factors affecting stone passage. CONCLUSIONS: Stone size, location, and underlying DM were confirmed to be significant predictive factors for spontaneous passage of ureteral stones. Urologists should consider active procedures, such as shock wave lithotripsy or ureteroscopy, rather than conservative management in patients presenting with proximally located stones, large ureteral stones, or underlying DM.
Adult ; Aged ; Diabetes Complications/*therapy ; Female ; Humans ; Male ; Middle Aged ; Prognosis ; Remission, Spontaneous ; Retrospective Studies ; Tomography, X-Ray Computed ; Treatment Outcome ; Ureteral Calculi/pathology/radiography/*therapy ; *Watchful Waiting

PURPOSE: The objective was to determine whether stone density on plain radiography (kidney-ureter-bladder, KUB) could predict the outcome of extracorporeal shockwave lithotripsy (ESWL) for ureteral stones. MATERIALS AND METHODS: A total of 223 patients treated by ESWL for radio-opaque ureteral stones of 5 to 20 mm were included in this retrospective study. All patients underwent routine blood and urine analyses, plain radiography (KUB), and noncontrast computed tomography (NCCT) before ESWL. Demographic, stone, and radiological characteristics on KUB and NCCT were analyzed. The patients were categorized into two groups: lower-density (LD) group (radiodensity less than or equal to that of the 12th rib, n=163) and higher-density (HD) group (radiodensity greater than that of the 12th rib, n=60). Stone-free status was assessed by KUB every week after ESWL. A successful outcome was defined as stone free within 1 month after ESWL. RESULTS: Mean stone size in the LD group was significantly smaller than that in the HD group (7.5+/-1.4 mm compared with 9.9+/-2.9 mm, p=0.002). The overall success rates in the LD and HD groups were 82.1% and 60.0%, respectively (p=0.007). The mean duration of stone-free status and average number of SWL sessions required for success in the two groups were 21.7 compared with 39.2 days and 1.8 compared with 2.3, respectively (p<0.05). On multivariate logistic analysis, stone size and time to ESWL since colic and radiodensity of the stone on KUB were independent predictors of successful ESWL. CONCLUSIONS: Our data suggest that larger stone size, longer time to ESWL, and ureteral stones with a radiodensity greater than that of the 12th rib may be at a relatively higher risk of ESWL failure 1 month after the procedure.
Adult ; Aged ; Colic ; Female ; Humans ; *Lithotripsy ; Male ; Middle Aged ; Multivariate Analysis ; Retrospective Studies ; Tomography, X-Ray Computed ; Treatment Outcome ; Ureteral Calculi/*radiography/*therapy

PURPOSE: To evaluate the distribution of ureteral stones and to determine their characteristics and expulsion rate based on their location. MATERIALS AND METHODS: We retrospectively reviewed computed tomography (CT) findings of 246 patients who visited our Emergency Department (ED) for renal colic caused by unilateral ureteral stones between January 2013 and April 2014. Histograms were constructed to plot the distribution of stones based on initial CT findings. Data from 144 of the 246 patients who underwent medical expulsive therapy (MET) for 2 weeks were analyzed to evaluate the factors responsible for the stone distribution and expulsion. RESULTS: The upper ureter and ureterovesical junction (UVJ) were 2 peak locations at which stones initially lodged. Stones lodged at the upper ureter and ureteropelvic junction (group A) had a larger longitudinal diameter (4.21 mm vs. 3.56 mm, p=0.004) compared to those lodged at the lower ureter and UVJ (group B). The expulsion rate was 75.6% and 94.9% in groups A and B, respectively. There was no significant difference in the time interval from initiation of renal colic to arrival at the ED between groups A and B (p=0.422). Stone diameter was a significant predictor of MET failure (odds ratio [OR], 1.795; p=0.005) but the initial stone location was not (OR, 0.299; p=0.082). CONCLUSIONS: The upper ureter and UVJ are 2 peak sites at which stones lodge. For stone size 10 mm or less, initial stone lodge site is not a significant predictor of MET failure in patients who have no previous history of active stone treatment in the ureter.
Adult ; Female ; Humans ; Kidney Pelvis/pathology ; Male ; Middle Aged ; Renal Colic/drug therapy/*pathology/radiography ; Retrospective Studies ; Sulfonamides/therapeutic use ; Tomography, X-Ray Computed ; Treatment Failure ; Ureter/pathology ; Ureteral Calculi/drug therapy/*pathology/radiography ; Urological Agents/therapeutic use

PURPOSE: This study aimed to assess the accuracy of low-dose dual-energy computed tomography (DECT) in predicting the composition of urinary calculi. MATERIALS AND METHODS: A total of 52 patients with urinary calculi were scanned with a 128-slice dual-source DECT scanner by use of a low-dose protocol. Dual-energy (DE) ratio, weighted average Hounsfield unit (HU) of calculi, radiation dose, and image noise levels were recorded. Two radiologists independently rated study quality. Stone composition was assessed after extraction by Fourier transform infrared spectroscopy (FTIRS). Analysis of variance was used to determine if the differences in HU values and DE ratios between the various calculus groups were significant. Threshold cutoff values to classify the calculi into separate groups were identified by receiver operating characteristic curve analysis. RESULTS: A total of 137 calculi were detected. FTIRS analysis differentiated the calculi into five groups: uric acid (n=17), struvite (n=3), calcium oxalate monohydrate and dihydrate (COM-COD, n=84), calcium oxalate monohydrate (COM, n=28), and carbonate apatite (n=5). The HU value could differentiate only uric acid calculi from calcified calculi (p<0.001). The DE ratio could confidently differentiate uric acid, struvite, calcium oxalate, and carbonate apatite calculi (p<0.001) with cutoff values of 1.12, 1.34, and 1.66, respectively, giving >80% sensitivity and specificity to differentiate them. The DE ratio could not differentiate COM from COM-COD calculi. No study was rated poor in quality by either of the observers. The mean radiation dose was 1.8 mSv. CONCLUSIONS: Low-dose DECT accurately predicts urinary calculus composition in vivo while simultaneously reducing radiation exposure without compromising study quality.
Adult ; Apatites/analysis ; Calcium Oxalate/analysis ; Female ; Humans ; Image Interpretation, Computer-Assisted/methods ; Kidney Calculi/chemistry/pathology/*radiography ; Magnesium Compounds/analysis ; Male ; Middle Aged ; Phosphates/analysis ; Prospective Studies ; Radiation Dosage ; Tomography, X-Ray Computed/methods ; Ureteral Calculi/chemistry/pathology/*radiography ; Uric Acid/analysis ; Waist Circumference ; Young Adult