Objective: To determine if there is a difference between postoperative urinary infection rates after retrograde intra-renal surgery (RIRS) when ureteral access sheath (UAS) was used or not used. Materials and methods: We retrospectively analyzed the medical records of all patients who underwent RIRS at our institution between January 2016 and October 2018. Results: 129 patients were included in the study. The mean age of the patients was 48.8 ± 12.1 years; 94 patients were male and 35 were female. The mean stone size (largest diameter), stone attenuation and stone volume were 15.3 ± 5.8 mm, 1038 ± 368 HU and 1098 ± 1031 mm3, respectively. Out of 129 patients, 81 were treated by using UAS (Group 1) and 48 were treated without use of UAS (Group 2). There was no statistically significant difference between the two groups in terms of post-operative infection (p = 0.608). However, the operative time of patients with post-operative infection was statistically higher than the other patients; 88.35 ± 22.5 min versus 59.37 ± 22.1 min (p = 0.017). In multivariate regression analysis, operation time (p = 0.02, r = 1.07) was found to be the sole predictor of post-operative infection. Conclusions: Using UAS during RIRS might reduce the intrarenal pressure and also has several advantages. However not prolonging the operation time too much could be of higher importance than UAS use in terms of preventing post-operative infection after RIRS.

Objective: To examine the relation between perirenal fat volume, which is one of the visceral fat measurements, and kidney stones. Method: 169 patients admitted to our clinic between January 2018 and May 2021 were included in the study. The patients were divided into 2 groups as Control Group and Unilateral Kidney Stone Group (88 patients with unilateral kidney stones). Contrast-enhanced abdominal computed tomography scans were used to measure perirenal fat volume and the results were transferred to workstations. The total perirenal fat volumes in the bilateral kidneys of patients were compared between the two groups. The perirenal fat volume in stone-bearing and non-stone bearing kidneys of patients were also compared. Results: The total perirenal fat volume was higher in the Unilateral Kidney Stone Group than in the other groups and the perirenal fat volume of the patients in this group was higher in the stone bearing kidney (295.6±164.4cm3) than in the non-stone bearing kidney (273.1±179.6cm3). In the ROC analysis, it was concluded that total perirenal fat volume>387cm3 increased the risk of kidney stones. Presence of hypertension, presence of hyperlipidemia and total perirenal fat volume>387cm3 were found to be independent risk factors for the presence of kidney stones. Conclusion: Perirenal fat volume is higher in stone bearing kidneys compared to non-stone bearing kidneys. Therefore, stone formation in a kidney is directly related to the perirenal fat volume of that kidney. Also, total perirenal fat volume>387cm3 increases the risk of kidney stones independently of body mass index, and predicts it better.

Background: To assess the effectiveness of T.O.HO. (Tallness, Occupied lesion, Houndsfield unit evaluation) score in predicting the retrograde intrarenal surgery (RIRS) success and to validate this scoring system. Methods: The age, sex, previous stone surgery, hospitalization, surgery duration, postoperative complication, stone length, stone location, stone density, stone number, lateralization, presence of hydronephrosis, and presence of preoperative stent datas of 611 patients who underwent RIRS in our clinic between January 2013 and January 2021 were retrospectively assessed. The patients were divided into two groups as successful and unsuccessful. The T.O.HO scores of all patients were calculated. Results: The success rate was 72.5%. Compared to the unsuccessful group, stone length and stone density were lower, surgery duration was shorter and there were less lower pole stones in the successful group (p < 0.001). No significant difference was found between the two groups in terms of the other parameters. The T.O.HO. score was significantly lower in the successful group compared to the unsuccessful group (p < 0.001). According to the multivariate logistic regression analysis, stone length (OR: 0.905; 95% Cl: 0.866–0.946; p < 0.001), lower pole location (OR: 0.546; 95% Cl: 0.013–0.296; p < 0.001), stone density (OR: 0.999; 95% Cl: 0.998–1; p = 0.044) and the T.O.HO. score (OR: 0.684; 95%Cl: 0.554–0.844; p < 0.001) were found as the independent risk factors for RIRS success. ROC curve analysis showed that the T.O.HO. score could predict the RIRS success with 7.5 cut-off point (AUC: 0.799, CI: 0.76–0.839; p < 0.001). Conclusion: The T.O.HO. score can predict RIRS success with a high rate of accuracy.

Uzun E, et al. Investig Clin Urol. 2024 Jan;65(1):53-61. https://doi.org/10.4111/icu.20230215