Ahmed R. El-Nahas

Bladder tumour staging: comparison of diffusion- and T2-weighted MR imaging

The aim of this work was to evaluate the clinical feasibility of diffusion-weighted (DW) MRI in detection and staging of urinary bladder tumour and to compare DW MRI with the T2-weighted technique. One hundred and six patients with bladder tumour were prospectively included in our study. All patients were evaluated with MR imaging. We started with axial T2-weighted high resolution MR of the urinary bladder, then DW MRI. Two radiologists independently interpreted the MR images, and discrepancies were resolved by consensus. The accuracy of DW MRI in staging of bladder tumour was evaluated using the final histopathological findings. In DW imaging (DWI) staging accuracy was 63.6% and 69.6% in differentiating superficial from invasive tumours and organ-confined from non-organ-confined tumours, respectively. On a stage by a stage basis, DWI accuracy was 63.6% (21/33), 75.7% (25/33), 93.7% (30/32) and 87.5% (7/8) for stages T1, T2, T3 and T4, respectively. In the T2-weighted technique, the overall staging accuracy was only 39.6% and accuracy for differentiating superficial from invasive tumours and organ-confined from non-organ-confined tumours was 6.1% and 15.1%, respectively. DW is superior to T2-weighted MRI in staging of organ-confined tumours (≤T2) and both techniques are comparable in the evaluation of higher-stage tumours.

Flexible ureterorenoscopy versus extracorporeal shock wave lithotripsy for treatment of lower pole stones of 10–20 mm

Study Type – Therapy (case series)

Semirigid Ureteroscopy for Ureteral Stones: A Multivariate Analysis of Unfavorable Results

PURPOSE We determined the factors predicting unfavorable results of semirigid ureteroscopy for ureteral calculi. MATERIALS AND METHODS We reviewed the computerized files of 841 patients who underwent a total of 908 ureteroscopic procedures for ureteral stones from January 2003 through December 2006. A semirigid 6/7.5Fr ureteroscope was used in pediatric patients and an 8/10Fr or 8.5/11.5Fr ureteroscope was used in adults. Patients with favorable results were those who became stone-free after a single ureteroscopic procedure without any complications. They were compared with patients who had unfavorable results using univariate (chi-square and t tests) and multivariate (logistic regression) statistical tests to identify risk factors for unfavorable results. RESULTS The study included 567 males and 274 females with a mean age of 48.5 years (range 2 to 81). The complication rate was 6.7% (61 procedures). The stone-free rate after a single ureteroscopic intervention was 87% (791 procedures). Favorable results were documented in 751 procedures (82.7%). Significant factors for unfavorable results were proximal ureteral stones, ureteroscopy done by surgeons other than experienced endourologists, stone impaction and stone width (relative risk 4, 2.5, 1.8 and 1.2, respectively). CONCLUSIONS Semirigid ureteroscopy is a safe and highly effective treatment modality for ureteral stones.

Factors Affecting Stone-free Rate and Complications of Percutaneous Nephrolithotomy for Treatment of Staghorn Stone

OBJECTIVE To determine factors affecting the stone-free rate and complications of percutaneous nephrolithotomy (PNL) for treatment of staghorn stones. METHODS The computerized database of patients who underwent PNL for treatment of staghorn stones between January 2003 and January 2011 was reviewed. All perioperative complications were recorded and classified according to modified Clavien classification system. The stone-free rate was evaluated with low-dose noncontrast computed tomography (CT). Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free and complication rates. RESULTS The study included 241 patients (125 male and 116 female) with a mean age of 48.7 ±14.3 years. All patients underwent 251 PNL (10 patients had bilateral stones). The stone-free rate of PNL monotherapy was 56% (142 procedures). At 3 months, the stone-free rate increased to 73% (183 kidneys) after shock wave lithotripsy. Independent risk factors for residual stones were complete staghorn stone and presence of secondary calyceal stones (relative risks were 2.2 and 3.1, respectively). The complication rate was 27% (68 PNL). Independent risk factors for development of complications were performance of the procedure by urologists other than experienced endourologist and positive preoperative urine culture (relative risks were 2.2 and 2.1, respectively). CONCLUSION Factors affecting the incidence of residual stones after PNL are complete staghorn stones and the presence of secondary calyceal stones. Complications are significantly high if PNL is not performed by an experienced endourologist or if preoperative urine culture is positive.

GreenLight™ Laser (XPS) Photoselective Vapo-Enucleation versus Holmium Laser Enucleation of the Prostate for the Treatment of Symptomatic Benign Prostatic Hyperplasia: A Randomized Controlled Study

PURPOSE After the advent of the GreenLight XPS™ (180 W) 532 nm laser, photoselective vapo-enucleation of the prostate could compete with holmium laser enucleation of the prostate as a size independent procedure. We assessed whether photoselective vapo-enucleation of the prostate-XPS is not less effective than holmium laser enucleation of prostate for improvement of lower urinary tract symptoms secondary to benign prostatic hyperplasia. MATERIALS AND METHODS A randomized controlled noninferiority trial comparing holmium laser enucleation of the prostate to photoselective vapo-enucleation of the prostate-XPS 180 W was conducted. I-PSS, flow rate, residual urine, prostate specific antigen and prostate volume changes as well as perioperative and late adverse events were compared. Noninferiority of I-PSS at 1 year was evaluated using a 1-sided test at 5% level of significance. The statistical significance of other comparators was assessed at the (2-sided) 5% level. RESULTS Overall 50 and 53 patients were included in the holmium laser enucleation and photoselective vapo-enucleation of the prostate groups, respectively. Operative time, hospital stay and time to catheter removal were comparable between the groups. There was significant, comparable improvement in I-PSS and post-void residual urine volume at 1, 4 and 12 months. After 4 months prostate size reduction was significantly higher in the holmium laser enucleation of prostate group (74.3% vs 43.1%, p=0.001). At 12 months maximum urine flow rate was significantly higher in the holmium laser enucleation of prostate group (26.4 ±11.5 vs 18.4 ±7.5 ml per second, p=0.03). Re-intervention was needed in 2 and 3 cases in the holmium laser enucleation and photoselective vapo-enucleation of the prostate groups, respectively (p=1.0). Mean estimated cost per holmium laser enucleation of prostate procedure was significantly lower than per photoselective vapo-enucleation of the prostate procedure. CONCLUSIONS Compared to holmium laser enucleation of prostate, GreenLight XPS laser photoselective vapo-enucleation of the prostate is safe, noninferior and effective in treatment of benign prostatic hyperplasia.

Shock Wave Lithotripsy Versus Semirigid Ureteroscopy for Proximal Ureteral Calculi (<20 mm): A Comparative Matched-pair Study

OBJECTIVES To use a matched-pair analysis design to compare the safety and efficacy of shock wave lithotripsy (SWL) and ureteroscopy (URS). Controversy still exists regarding whether SWL or URS is the best management of upper ureteral calculi. METHODS We reviewed the records of patients with a single radiopaque upper ureteral stone treated by URS or SWL from January 2003 to December 2005. SWL was performed as an outpatient procedure using the electromagnetic lithotripter (Dornier Lithotripter S). URS was performed using an 8F or 8.5F semirigid ureteroscope. Intracorporeal lithotripsy with pneumatic or holmium laser energy was used when needed. A matched-pair analysis was performed using 3 parameters (sex, stone size, and degree of hydronephrosis). The success rates, retreatment rates, auxiliary procedures, and complications were compared in each group. RESULTS A total of 427 patients were treated for upper ureteral stones. Forty-three matched pairs were identified and compared. The success rate was 83.7% for SWL vs 88.4% for URS (P = .8). The retreatment rate was significantly greater in the SWL group than in the URS group (65% vs 2.3%, respectively; P < .001). The need for auxiliary procedures was equal in both groups (16.3%). The complication rate was 14% in the URS group and 4.7% in the SWL group (P = .1). CONCLUSIONS SWL and semirigid URS are highly effective in the treatment of proximal ureteral stones <20 mm. The results of our study showed that SWL was safer and less invasive, but that URS was more effective and resulted in a lower retreatment rate.

Long-Term Effects of Extracorporeal Shock Wave Lithotripsy on Renal Function: Our Experience With 156 Patients With Solitary Kidney

PURPOSE We studied the long-term impact of shock wave lithotripsy on renal function, stone recurrence and hypertension in patients with a solitary kidney. Patients with a solitary kidney provide a unique opportunity to evaluate any clinically significant change in renal function. MATERIALS AND METHODS We retrospectively reviewed the records of 156 patients with stones in a solitary kidney treated with shock wave lithotripsy monotherapy. Treatment outcome was evaluated after 3 months. Long-term followup (more than 12 months) was available for 108 patients. Serum creatinine, systolic and diastolic blood pressure, new onset hypertension, calculated glomerular filtration rate, and kidney morphology were determined before and after treatment, and compared by chi-square, paired and unpaired t tests. RESULTS After 3 months the overall stone-free rate was 80.8% (126 of 156). Renal obstruction caused by steinstrasse after shock wave lithotripsy occurred in 14 (8.9%) patients. Secondary procedures were required in 20 (12.8%) patients. Followup ranged from 1 to 16 years with a mean of 3.8 (SD +/- 3.5). After long-term followup the stone-free rate was 76.8% and real stone recurrence developed in 18.5% of patients. There was no significant difference in any evaluated pretreatment or posttreatment parameters. CONCLUSIONS The demonstrated effectiveness, small number of complications at short-term followup, insignificant effect on renal function, blood pressure and relatively small number of recurrences at the long-term followup confirm that shock wave lithotripsy is not only effective but is also safe in the long run.

Prospective, Randomized Comparison of Ureteroscopic Endopyelotomy Using Holmium:YAG Laser and Balloon Catheter

PURPOSE We compared the safety and efficacy of the 2 retrograde endopyelotomy techniques. MATERIALS AND METHODS A prospective study was done from January 2001 to October 2003. Preoperative radiological evaluation included excretory urography, multiphasic helical computerized tomography and diuretic renography. Exclusion criteria were marked hydronephrosis, ipsilateral renal function less than 25% and renal stones or a significant crossing vessel at the ureteropelvic junction. Eligible patients were randomized to ureteroscopic laser endopyelotomy and retrograde Acucise endopyelotomy (20 per group). UPJ obstruction was primary in 14 patients and secondary in 26. The ureteropelvic junction was incised in the lateral direction and an endopyelotomy Double-J stent (Medical Engineering Corp., New York, New York) was left for 6 weeks. Subjective and objective outcomes were evaluated 3 and 6 months after stent removal, and every 6 months thereafter. RESULTS Mean operative time +/- SD was comparable in the laser and Acucise groups (64.7 +/- 22.4 and 58.7 +/- 20.2, respectively). The overall complication rate in the Acucise group was more than in the laser group (25% vs 10%). At a mean followup of 29.9 +/- 10.8 months (range 6 to 48) the laser group showed a higher success rate than the Acucise group (85% vs 65%) but the difference in the complication and success rates was not statistically significant. CONCLUSIONS Despite the advanced endourological skills required for ureteroscopic laser endopyelotomy its safety and efficacy seem to be better than those of Acucise endopyelotomy. However, a larger number of patients is needed to confirm these findings.

Functional and morphological effects of postpercutaneous nephrolithotomy superselective renal angiographic embolization.

OBJECTIVES To evaluate the functional and morphological effects of postpercutaneous nephrolithotomy (PCNL) superselective renal angiographic embolization. METHODS Between January 1995 and March 2006, superselective renal angiography was needed to control severe bleeding after 41 of 4095 PCNL procedures (1%). We evaluated the short-term effects of embolization after 3 months with renal ultrasonography (RUS), dimercaptosuccinic acid (DMSA) renal scan, and estimation of serum creatinine. We evaluated long-term morphological and functional effects with RUS, DMSA renal scan, and excretory urography (IVU). RESULTS Bleeding was controllable with superselective embolization in 38 patients (93%). Six of them developed early postembolization complications, in the form of perinephric hematoma in 4 and urinary leakage in 2 patients. At 3 months, serum creatinine levels increased in 3 of 9 patients with a solitary kidney, but none required renal replacement therapy. Long-term follow-up was completed for 30 patients for a mean period of 3.9 +/- 2.3 years. We performed IVU for 27 patients. Among them, 2 renal units (7%) showed no dye excretion. DMSA scans showed homogeneous distribution of radiotracer with no evidence of photopenic areas in 6 renal units (20%). The mean percentage of DMSA uptake by the corresponding kidney improved from 25 +/- 9% at the 3-month scans to 34 +/- 11% at the last follow-up scans (P <0.001). CONCLUSIONS The short-term deleterious effects of superselective renal embolization for post-PCNL renal vascular injuries were more pronounced in patients with a solitary kidney. However, the long-term follow-up showed functional and morphological improvements.

SAFETY AND EFFICACY OF SUPRACOSTAL PERCUTANEOUS NEPHROLITHOTOMY IN PEDIATRIC PATIENTS

PURPOSE This study was conducted to evaluate the safety and efficacy of the supracostal approach for percutaneous nephrolithotomy in pediatric patients. MATERIALS AND METHODS We retrospectively reviewed 60 percutaneous nephrolithotomy procedures done in 50 children (32 boys and 18 girls) between 2000 and 2007. Mean patient age was 7 +/- 4 years (range 9 months to 14 years). Noncontrast computerized tomography was the primary radiological investigation for most of the cases. The subcostal approach was used in 40 procedures, and the supracostal approach (above the 12th rib) was required in 20. We compared both approaches regarding preoperative characteristics, stone-free and complication rates, and the need for auxiliary procedures. RESULTS The preoperative characteristics of the patients, urinary tracts and stones were comparable for both treatment groups. There were no major complications. Significant bleeding requiring blood transfusion was observed in 3 patients (5%), transient fever in 3 (5%) and urinary leakage through the nephrostomy site in 3 (5%). The distribution of complications among subcostal and supracostal approaches was comparable. Of the 60 renal units 46 (77%) were stone-free after percutaneous nephrolithotomy at discharge from the hospital. Of the remaining 14 units 9 (15%) were stone-free after shock wave lithotripsy and 5 (8%) had insignificant residual stones. Therefore, the overall stone-free rate at 3 months was 92.5%. Comparing the subcostal and supracostal approaches, there were no significant differences between hospital stays, complication rates, unplanned auxiliary procedures, and stone-free rates at discharge home and at 3-month followup. CONCLUSIONS Percutaneous nephrolithotomy for treating renal stones in children provides a high degree of safety and efficacy whether a supracostal or subcostal approach is used.