Background/Aim: To investigate the seasonal variations of the incidence of renal colic by a computerized analysis of cyclic climatic features. Methods: 1,163 consecutive patients with acute renal colic were studied. Eigendecomposition and signal reconstruction of district temperature and humidity were performed to establish any cyclic variation. Average temperatures and humidity values were calculated at time periods of 15, 30, 45 and 60 days preceding each renal colic. Results: Patients were allocated to groups every 30 days, since eigendeanalysis suggested that intervals of this duration have homogeneous climatic features. With an average time period of 15 days preceding each renal colic, a positive correlation coefficient of temperature (r = +0.75 with CI 0.31–0.93, p < 0.005) and a cubic relationship at the regression analysis (R = 82.4%, p = 0.015) were found with the onset of colics. We observed a negative correlation between humidity and renal colic (rho = –0.70 with CI –0.92 to –0.21, p < 0.01), with an inverse relation as regression model (R = 57.9%, p < 0.05). Conclusions: We demonstrated an association between the onset of renal colics and exposure to hot and dry weather, particularly when temperatures rose above 27°C and relative humidity fell below 45%.

The objective of this study was to optimally predict the spontaneous passage of ureteral stones in patients with renal colic by applying for the first time support vector machines (SVM), an instance of kernel methods, for classification. After reviewing the results found in the literature, we compared the performances obtained with logistic regression (LR) and accurately trained artificial neural networks (ANN) to those obtained with SVM, that is, the standard SVM, and the linear programming SVM (LP-SVM); the latter techniques show an improved performance. Moreover, we rank the prediction factors according to their importance using Fisher scores and the LP-SVM feature weights. A data set of 1163 patients affected by renal colic has been analyzed and restricted to single out a statistically coherent subset of 402 patients. Nine clinical factors are used as inputs for the classification algorithms, to predict one binary output. The algorithms are cross-validated by training and testing on randomly selected train- and test-set partitions of the data and reporting the average performance on the test sets. The SVM-based approaches obtained a sensitivity of 84.5% and a specificity of 86.9%. The feature ranking based on LP-SVM gives the highest importance to stone size, stone position and symptom duration before check-up. We propose a statistically correct way of employing LR, ANN and SVM for the prediction of spontaneous passage of ureteral stones in patients with renal colic. SVM outperformed ANN, as well as LR. This study will soon be translated into a practical software toolbox for actual clinical usage.

Introduction/Objective Although phosphodiesterase 5 (PDE 5) inhibitors represent the gold standard for medical treatment of erectile dysfunction (ED), they are not curative. Over the recent years, low-intensity extracorporeal shock wave therapy (LI-ESWT) has been proposed as a valid non-invasive therapy approach for ED. The aim of our work is to assess the shortened, three-week low-intensity extracorporeal shock wave therapy of vasculogenic ED. Methods The study involved 32 patients with an International Index of Erectile Function (IIEF) score between 5 and 20, and whose vasculogenic ED had been proven through Doppler ultrasound. All the patients had a washout period of one month after previous therapy and agreed to discontinue the PDE5-I therapy during the follow-up. The LI-ESWT was applied for three weeks, twice weekly, without repeating. The patients were evaluated at baseline, after one, three, and six months with the IIEF, Doppler ultrasound, and the Beck Depression Inventory. Results All investigated parameters (International Index of Erectile Function, Beck Depression Inventory and penile Doppler ultrasound parameters) showed statistically significant improvement just one month after the treatment, compared to pre-treatment values, in all investigated domains. The international index of erectile function passed from baseline values of 12.75 ± 4.62 to 14.87 ± 5.04 at one month after treatment (p < 0.01). This trend remained positive in IIEF and all the parameters tested at the three-month and six-month follow-up. Conclusion The shortened three-week low-intensity shock wave treatment of vasculogenic erectile dysfunction proved to be clinically effective.