Management of staghorn renal stones.

Staghorn stones are large branching stones that fill part of all of the renal pelvis and renal calyces and they can be complete or partial depending on the level of occupancy of the collecting system. Although kidney stones are commoner in men, staghorn stones are less often reported in men compared to women and they are usually unilateral. Due to the significant morbidity and potential mortality attributed to staghorn stones, prompt assessment and treatment is mandatory. Conversely, conservative treatment has been shown to carry a mortality rate of 28% in 10-year period and 36% risk of developing significant renal impairment. Staghorn stones are, therefore, significant disease entity that should be managed aggressively and effectively. Generally, the gold standard treatment for staghorn stones is surgical with a view to achieve stone-free collecting system and preserve renal function. Percutaneous nephrolithotomy should be the recommended first-line treatment for staghorn stones. Other non-surgical options are usually considered in combination with surgery or as monotherapy only if patients are surgically unfit. The decision for optimal treatment of staghorn stones should be individualized according to the circumstances of the patient involved and in order to do so, a closer look at the advantages and disadvantages of each option is necessary.

Evaluation of Tl-201 SPECT imaging findings in prostate cancer.

OBJECTIVES: To compare with histopathological findings the findings of prostate cancer imaging by SPECT method using Tl-201 as a tumor seeking agent. METHODS: The study comprised 59 patients (age range 51-79 years, mean age 65.3 ± 6.8 years) who were planned to have transrectal ultrasonography (TRUS)-guided biopsies due to suspicion of prostate cancer between April 2011 and September 2011. Early planar, late planar and SPECT images were obtained for all patients. Scintigraphic evaluation was made in relation to uptake presence and patterns in the visual assessment and to Tumor/Background (T/Bg) ratios for both planar and SPECT images in the quantitative assessment. Histopathological findings were compatible with benign etiology in 36 (61%) patients and malign etiology in 23 (39%) patients. Additionally, comparisons were made to evaluate the relationships between uptake patterns,total PSA values and Gleason scores. RESULTS: A statistically significant difference was found between the benign and malignant groups in terms of uptake in planar and SPECT images and T/Bg ratios and PSA values. No statistically significant difference was found between uptake patterns of planar and SPECT images and Gleason scores in the malignant group. CONCLUSIONS: SPECT images were superior to planar images in the comparative assessment. Tl-201 SPECT imaging can provide an additional contribution to clinical practice in the diagnosis of prostate cancer and it can be used in selected patients.

In vivo porcine model for practicing retrograde intrarenal surgery.

OBJECTIVES: To examine the feasibility of retrograde intrarenal surgery (RIRS) in a porcine model. MATERIALS AND METHODS: Female pigs (n = 3) were placed in a dorsal lithotomy position under general anesthesia, and stone material was inserted into the renal pelvis of the pigs. The bladder was entered with a cystoscope, and a 0.038-inch hydrophilic guidewire was passed into the renal pelvis. Following successful placement of the guidewire, a ureteral access sheath (9.5/11.5 Fr) was placed to allow for optimal visualization. A 7.5-Fr flexible ureteroscope (Karl Storz Flex-X2) and a 200-µm laser fiber were used for lithotripsy. When basketing was deemed necessary, zero-tipped nitinol stone baskets were used. Trainees then practiced all these manipulations on the model. RESULTS: Urologists with moderate experience in advanced endourologic surgery were trained using this model. However, there were some surgical difficulties due to the urinary system anatomy of the pig. Intravaginal location of the urethra, bladder neck location of the ureters, tight ureteric orifices, tortuous ureters, longitudinally elongated renal pelvis, narrow infundibulopelvic angle and shallow calices made the passage of the instruments and maneuverability of the flexible ureteroscope more difficult than in a human model. CONCLUSIONS: Despite some difficulties, our porcine model was very effective, because all the trainees successfully practiced the RIRS manipulations on this model.

Comparison of ultrasonic and pneumatic intracorporeal lithotripsy techniques during percutaneous nephrolithotomy.

OBJECTIVES: To compare the effectiveness and safety of ultrasonic and pneumatic lithotripters in the treatment of renal stone disease. MATERIALS AND METHODS: A total of 227 consecutive percutaneous nephrolithotomy procedures for renal calculi were performed. In 107 patients ultrasonic lithotriptors were used (group I) and in 83 patients pneumatic lithotriptors were used (group II). In the remaining 37 patients, stones were managed with both pneumatic and ultrasonic lithotripters. Follow-up studies included intravenous urography (IVU) and/or computed tomography (CT). RESULTS: The mean operative time and duration of hospitalization were similar between the groups. In the ultrasonic treatment group, 100 (96.9%) patients were stone-free on postoperative day 1 and 5 (4.6%) went on to undergo an additional treatment modality, resulting in a total stone-free rate of 97.2%. In the pneumatic lithotripsy group, 68 (81.9%) patients were stone-free after the primary procedure on the first day and 15 (18.1%) went on to undergo an additional treatment modality, resulting in a stone-free rate of 91.5%. The final stone-free rates at 3 months postoperatively in groups I, II, and III were 97.2%, 91.5%, and 87.9%, respectively (P = 0.826). CONCLUSIONS: We conclude that both ultrasonic and pneumatic lithotripters are effective and safe for intracorporeal lithotripsy. However, the ultrasonic lithotripter provides higher stone-free rates with similar morbidity compared with pneumatic devices.

Are small residual stone fragments really insignificant in children?

OBJECTIVES: To assess the significance of asymptomatic residual stone fragments of less than 4mm (clinically insignificant residual fragments [CIRFs]) after shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PNL), and retrograde intrarenal surgery (RIRS) in children. PATIENTS AND METHODS: Eighty-five children were followed up for 6 to 50months (median 22). Outcomes measured were fragment re-growth, stone events (emergency department visits, hospitalization, or additional interventions) and spontaneous fragment passage. RESULTS: During follow-up, 22 children (25.8%) passed residual fragments spontaneously. Highest spontaneous passage rate was found for renal pelvis stones and the lowest for the lower pole stones (57.1% vs. 16.1%; p<0.001). When the number of the fragments increased, the chance of the spontaneous passage decreased (30% vs 20%; p<0.05). Symptomatic episodes including renal colic, hematuria, or urinary tract infection were documented in 34 (40%) patients, and re-growth of fragments was observed in 18 (21.2%). Stone size had no significant effect on spontaneous passage (p=0.079), stone growth (p=0.528), and symptomatic episodes (p=0.402). Twenty-five patients (29.4%) required secondary intervention for stone re-growth or stone related events and the remaining 20 patients (23.5%) needed medical treatment for bothersome symptoms or complications. CONCLUSIONS: Our results suggest that 40% of children with CIRFs will become symptomatic and 20% will develop stone re-growth over the following 6months. Only one fifth of the fragments will pass spontaneously without any complications. Therefore, the use of the term "CIRF" is not appropriate for postoperative residual fragments in children.

Comparison of retrograde intrarenal surgery, shockwave lithotripsy, and percutaneous nephrolithotomy for treatment of medium-sized radiolucent renal stones.

OBJECTIVES: To compare the outcomes of shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PNL), and retrograde intrarenal surgery (RIRS) for 10-20 mm radiolucent renal calculi by evaluating stone-free rates and associated complications. PATIENTS AND METHODS: A total of 437 patients at 7 institutions who underwent SWL (n = 251), PNL (n = 140), or RIRS (n = 46) were enrolled in our study. Clinical success was defined as stone-free status or asymptomatic insignificant residual fragments <3 mm. The success rates, auxiliary procedures, and complications were compared in each group. RESULTS: Success rates were 66.5, 91.4, and 87% for SWL, PNL, and RIRS (p < 0.001). The need for auxiliary procedures was more common after SWL than PNL and RIRS (21.9 vs 5.7 vs 8.7%, respectively; p < 0.001). The overall complication rates for the SWL, PNL, and RIRS were 7.6, 22.1, and 10.9%, respectively (p < 0.001). Thirteen patients in PNL group received blood transfusions, while none of the patients in RIRS and SWL groups transfused. Hospitalization time per patient was 1.3 ± 0.5 days in the RIRS group, while it was 2.6 ± 0.9 days in the PNL group (p < 0.001). Fluoroscopy and operation time were significantly longer in the PNL group compared to RIRS (145.7 ± 101.7 vs 28.7 ± 18.7 s, and 57.5 ± 22.1 vs 43.1 ± 17 min, respectively). CONCLUSIONS: For treatment of moderate-sized radiolucent renal stones, RIRS and PNL provide significantly higher success and lower retreatment rate compared with SWL. Although PNL is effective, its biggest drawback is its invasiveness. Blood loss, radiation exposure, hospital stay, and morbidities of PNL can be significantly reduced with RIRS technique.

Prediction of morbidity and mortality after percutaneous nephrolithotomy by using the Charlson Comorbidity Index.

OBJECTIVES: To determine whether the Charlson Comorbidity Index (CCI) predicts postoperative medical complications and death in patients treated with percutaneous nephrolithotomy (PCNL). METHODS: A total of 1406 PCNL procedures were performed at 4-stone referral centers between September 2004 and March 2011 were reviewed in this multicenter study. Variables included patient and stone characteristics, preoperative comorbidities, intraoperative data, and postoperative complications, including mortality. RESULTS: The present study included 868 (61.7%) men and 538 (38.3%) women. Mean patient age was 44.1 years (range 1-81). CCI score was calculated as "0" for 993 patients (70.6%, called group I), "1" for 316 patients (22.5%, called group II) and"≥2" for 97 patients (6.9%, called group III). The incidence of comorbidities increased with age (P=.001). The overall postoperative complication rate was 29.3%. Life-threatening medical complications developed in 2.9% of patients in group I, 7.6% of patients in group II, and 21.6% of patients in group III, (P=.001). There were 3 deaths for an overall 0.2% mortality rate. Perioperative bleeding requiring blood transfusion was observed in 9.5% of patients, and we found an increased risk of hemorrhage associated with CCI score (P=.049). High CCI score, patient age, hemorrhage, and operative time were significantly related to higher medical complication rates after PCNL. CONCLUSIONS: CCI is a quick, simple, and reproducible scoring system that accurately predicts the morbidity and mortality of PCNL.

Tissue effects of intracorporeal lithotripsy techniques during percutaneous nephrolithotomy: comparison of pneumatic and ultrasonic lithotripters on rat bladder.

The objectives of this study were to determine the tissue effects of ultrasonic and pneumatic lithotripsy on the rat urothelium. The rats were divided into three groups. Groups I and II consisted of ten rats each that underwent intracorporeal lithotripsy (pneumatic and ultrasonic lithotripsy, respectively). Group III contained ten control rats and no lithotripsy method was used, they served as references for absence of injury. The light microscopy findings were evaluated as follows: squamous metaplasia, papillary projection, inflammation, increased stratification, and stone formation. In five (71.4%) animals of group II, bladders were edematous and hemorrhagic, macroscopically. Histologically, the bladder wall was normal in four rats of group I and in one of group II. There was a significant increase in inflammation (31.5%), squamous metaplasia (85.7%), papillary projection (71.4%), increased stratification (71.4%), and microscopic or macroscopic stone formation (85.7%) in the bladder wall of group II rats in comparison with group I and control group. In the rat model, we noted that ultrasonic devices have a potential risk for tissue injury. In turn, this was associated with a markedly increased deposition of CaOx stones in the kidney. When confronted with harder stones, pneumatic lithotripsy can be more effective while also minimizing tissue injury.

Can we avoid percutaneous nephrolithotomy in high-risk elderly patients using the Charlson comorbidity index?

OBJECTIVE: To determine whether Charlson comorbidity index (CCI) predicts the postoperative complications after percutaneous nephrolithotomy (PCNL) and could be a plausible option to avoid surgery and its potential risks in elderly patients with significant comorbidites. METHODS: The data from 283 elderly patients (age ≥ 60 years) who underwent PCNL in 4 large referral hospitals were reviewed in the present multicenter study. For each patient, we evaluated pre-existing comorbidities and calculated the CCI score. The patients were classified to 3 CCI score categories (0, 1, ≥ 2) and compared regarding the stone-free and complications rates. RESULTS: The mean patient age was 64.7, 65.6, and 67.7 years in the 3 groups. The stone-free rate after primary PCNL was 85.7% in group 1, 86.1% in group 2, and 75.0% in group 3. These rates increased to 90.8%, 95.4%, and 83.9% after a second intervention (P = .049). The overall postoperative complication rate was 38.8%. The most common complication was hemorrhage necessitating blood transfusion in 34 patients (12%), and we found an increased risk of hemorrhage associated with the CCI score (P = .011). Life-threatening medical complications developed in 7.6% of the patients in group 1, 12% of the patients in group 2, and 28.6% of the patients in group 3 (P = .001). A multivariate logistic regression analysis showed that a high CCI score, bleeding, and operative time had significant influence on the postoperative medical complication in this population. CONCLUSION: Conservative management of asymptomatic large kidney stones appears to be a safe alternative to PCNL in elderly patients with significant comorbidites.