External validation of a nomogram for outcome prediction in management of medium-sized (1-2 cm) kidney stones.

Background: Stone nomogram by Micali et al., able topredict treatment failure of shock-wave lithotripsy (SWL), retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL) in the management of single 1-2 cm renal stones, was developed on 2605 patients and showed a high predictive accuracy, with an area under ROC curve of 0.793 at internal validation.

Flexible ureteroscopy without ureteral access sheath.

Introduction: Ureteral access sheath (UAS) is widely used in flexible ureteroscopy and laser lithotripsy (FURS) based on better stone-free rates, lower intrarenal pressure and fewer complications. However, it also rises surgical costs and may injure the ureteral wall. The main objective of our study is to compare safety and efficacy of FURS with and without UAS to evaluate whether its use is justified in all cases.

Percutaneous nephrolithotomy: technique.

Percutaneous nephrolithotomy (PCNL) is considered to be the first line of treatment for large renal stones. Though PCNL comes with higher morbidity, its efficacy is unbeaten by other minimally invasive modalities. However, potential complications, such as bleeding, occur.

[Management of malignant ureteral obstruction.].

Objective: To describe the different therapeutic alternatives in malignant ureteral obstruction (MUO), and to analyze short and long-term results.

Methods: We conducted a bibliographic search about MUO in Spanish and English languages in PubMed and Google Scholar. We examined the most relevant reviews, original manuscripts and their respective citations.

Pyelocaliceal Distribution of Kidney Stones Used as an Outcome Predictor in Percutaneous Nephrolithotomy After Being Evaluated with Preoperative and Postoperative CT Scan.

Objective: To identify kidney stone characteristics that will determine either success or failure of a percutaneous nephrolithotomy (PCNL) and design a classification system to predict results according to these characteristics.

Materials And Methods: One hundred thirty-eight patients were assessed with multislice abdominal and pelvic CT before and after PCNL. With regard to pyelocaliceal stone distribution, we classified our patients in two groups that we called "no extra stone in middle calix" (NESMC) and "extra stone in middle calix" (ESMC), according to the difficulty in reaching the stones.