Area of hydronephrosis is a useful predictive factor of impacted ureteral stones.

Ureteroscopic lithotripsy for impacted stones is challenging, but it is important to predict impacted stones preoperatively. Hydronephrosis, which is evaluated by a grading system, is often apparent in impacted stones. However, the currently used grading system is a qualitative evaluation. We, therefore, focused on a quantitative evaluation: the area of hydronephrosis. The aim of this study was to investigate whether the area of hydronephrosis could predict impacted stones more accurately than Society for Fetal Urology grade. We retrospectively identified 160 patients who underwent ureteroscopic lithotripsy for ureteral stones at our hospital between January 2014 and April 2022. Impacted stones were defined as stones fixed to the ureteral wall that could not be moved by means of ureteroscopic manipulation or water pressure. Of the 160 patients, 54 (33.8%) had impacted stones. Comparing patient characteristics, there were significant differences in stone size, ureteral wall thickness, Society for Fetal Urology grade, renal pelvic width and area of hydronephrosis (all P < 0.01). Receiver operating characteristic analysis showed that area of hydronephrosis was the more significant predictive value (area under the curve 0.781) compared with Society for Fetal Urology grade (area under the curve 0.676, P < 0.01). Multivariate analysis revealed that significant independent predictive factors of impacted stones were thicker ureteral wall thickness and larger area of hydronephrosis (both P < 0.01). The area of hydronephrosis and ureteral wall thickness were significant predictors of impacted stones in patients undergoing ureteroscopic lithotripsy for ureteral stones. These factors may be useful for selecting the treatment and preoperative settings.

Efficacy of Bisphosphonate for Urolithiasis Complicated by Osteogenesis Imperfecta.

A 44-year-old man with osteogenesis imperfecta presented with left renal colic. Non-contrast computed tomography revealed a stone (10×9 mm) in the left upper ureter. Ureteroscopic lithotripsy was performed twice and stone-free status was achieved. An analysis of the stone revealed a mixed composition including calcium oxalate and calcium phosphate. Postoperatively, we administered bisphosphonates to prevent recurrence of urolithiasis, as 24-hour urine collection revealed marked hypercalciuria. Eighteen months after surgery, the urinary calcium levels had normalized, and there was no recurrence of urolithiasis. Osteogenesis imperfecta can be complicated by urolithiasis, but bisphosphonates may be useful in preventing recurrence of this disease.

In vitro comparison of simulated intrapelvic pressure in an artificial kidney model during retrograde intrarenal surgery among various single-use ureteroscopes.

OBJECTIVES: This study compares intrapelvic pressure (IPP) during retrograde intrarenal surgery with various single-use flexible ureteroscopes (f-URS) in an artificial kidney model. METHODS: We created an artificial kidney model with a pressure sensor using a bladder evacuation device. The model was completely closed and the only backflow was on the side of the ureteroscope inside the ureteral access sheath (UAS). We tested five single-use f-URSs (LithoVue, Wiscope, PU3022A, PU3033A, and AXIS) with six different types of UAS (9.5/11.5-14/16 Fr). Using the automatic irrigation system, 30 s of irrigation was performed at various pressures (40-180 mmHg) and steady-state IPP was recorded. IPP was compared between the five single-use f-URSs. IPP cutoff value was determined at 30 mmHg. The diameter of the endoscope tip and the curved and shaft parts were also measured and recorded. RESULTS: The diameters of all parts were significantly different between single-use f-URSs. The maximum IPP tended to be higher in ureteroscopes with larger diameters of the proximal parts (curved part/shaft part). In LithoVue and Uscope PU3022A f-URSs, the maximum IPP did not exceed 30 mmHg when UAS ≥12/14 Fr was used. In AXIS and Wiscope f-URSs, it did not exceed the cutoff value when the UAS ≥11/13 Fr was used. In Uscope PU3033A f-URS, it did not exceed 30 mmHg when the UAS ≥10/12 Fr was used. CONCLUSIONS: Maximum IPP tended to be higher in f-URSs with larger diameters of the proximal part and the appropriate size of the UAS differed between various single-use f-URSs.

Poor performance status is a risk factor for higher detection of Gram positive coccus in stone-related pyelonephritis.

INTRODUCTION: We aimed to investigate the detection rate of causative organisms in stone-related pyelonephritis and to compare their distribution according to patient backgrounds. METHODS: We retrospectively identified patients with stone-related pyelonephritis. Clinical data were collected between November 2012 and August 2020 at Wakayama Medical University Hospital, including on patient backgrounds and causative organisms. Patients were categorized by Eastern Cooperative Oncology Group performance status (PS) as the good PS group (0, 1) and the poor PS group (2-4). Bacteria were divided into Gram-positive cocci (GPC) or non-GPC groups and logistic regression analysis was used to examine factors that predict detection of GPC. RESULTS: Seventy-nine patients had stone-related pyelonephritis, 54 (68.4 %) in the good PS group and 25 (31.6 %) in the poor PS group. In the good PS group, Escherichia coli (67 %) was followed by Klebsiella species (9 %), while in the poor PS group, Escherichia coli (20 %) was followed by Enterococci and Staphylococci (12 %). GPC detection rate was significantly higher in the poor PS group than in the good PS group (40.0 % vs 14.8 %, p = 0.016), and multivariate logistic regression analysis showed that poor PS was an independent factor predicting detection of GPC (OR = 6.54, p = 0.02). CONCLUSIONS: The distribution of the causative organisms in stone pyelonephritis was similar to that in common complicated urinary tract infections. Poor PS may be an independent predictor of GPC detection in patients with stone pyelonephritis.

Dynamic Changes in Fluid Temperatures during Laser Irradiation Using Various Laser Modes: A Thermography-Based In Vitro Phantom Study.

The differences in dynamic thermal changes during laser lithotripsy between various laser pulse modes are unclear. We used thermography to evaluate the temporal changes in high-temperature areas during laser activation in order to compare different laser pulse modes. An unroofed artificial kidney model was used for the experiments. The laser fired for 60 s with a laser setting of 0.4 J/60 Hz in the following four different laser pulse modes without saline irrigation: short pulse mode (SPM), long pulse mode (LPM), virtual basket mode (VBM) and Moses mode (MM). Using the first 30 s of moving images, we compared the ratio of a high-temperature area of >43 °C to the total area every 5 seconds. The dynamic changes in fluid temperatures were shown to be different between the laser pulse modes. The extent of the high-temperature areas during the laser activation was large in the LPM and MM compared with the SPM and VBM. While the high-temperature areas expanded in an anterior direction in the early laser irradiation period using the LPM, they spread in a posterior direction in the early laser activation period using the MM. Although only the temperature profile in one specific plane was investigated, these results are considered useful for preventing thermal injuries during retrograde intrarenal surgeries.

Thermography-Based Comparison of Irrigation Temperatures Between Moses Mode and Virtual Basket Mode: An In Vitro Phantom Study.

Objectives: This study aims to evaluate changes in irrigation fluid temperatures during laser activation by using thermography, with comparison between Moses mode (MM) and virtual basket mode (VBM). Materials and Methods: Experiments were performed using an unroofed pyelocaliceal model. The laser was fired for 60 seconds at 0.4 J/60 Hz. Three runs were tested per setting using short pulse mode, long pulse mode, MM contact, and VBM. The time to reach threshold of thermal injury (43°C) was evaluated using thermometer and thermography, both with and without saline irrigation (25 mL/min). These outcomes were compared between laser pulse modes. Results: In measurement of time to reach the threshold, thermography-based time was significantly shorter than thermometer-based time in all laser modes under the condition of no irrigation. Thermography measurement results indicate that the speed of temperature rise depends on laser pulse modes, and the time to reach the threshold in MM was significantly shorter than that in VBM (9.0 seconds vs 14.3 seconds, p = 0.03). When 25 mL/min saline irrigation was used, the peak temperatures by both thermometer and thermography measurements did not exceed the threshold during laser activation. Conclusions: Thermography-based evaluation suggests that irrigation temperatures near mucosa around stones can rapidly elevate during laser lithotripsy when the irrigation condition is poor. Temperature rise speed in MM may be more rapid than that in VBM. To prevent thermal injury, laser pulse modes must be used selectively according to the condition of irrigation.

The ratio of CT attenuation values of the ureter above/below ureteral stones is a useful preoperative factor for predicting impacted ureteral stones.

Impacted stones typically make it difficult to perform ureteroscopic lithotripsy (URSL), so it is useful to preoperatively predict such impaction. We focused on CT attenuation values of the ureter above and below the stone ('HU above' and 'HU below') and calculated their ratio (HAB ratio; HU above/HU below ratio). The aim was to investigate whether HAB ratio could predict impacted stones preoperatively. Between 2011 and 2019, 171 patients from our hospital that had URSL for ureteral stones with pretreatment non-contrast computed tomography (NCCT) were retrospectively identified. Ureteral wall thickness (UWT), ureteral wall volume (UWV) and HAB ratio ('HU above' divided by 'HU below') were recorded. Impacted stones were defined as fixed stones that did not move by means of ureteroscopic manipulation or water pressure. Of the 171 procedures, 46 (27%) involved patients with impacted stones. Comparing patient characteristics and stone parameters according to impaction status, factors with significant difference included grade of hydronephrosis, UWT, and HAB ratio (all P < 0.01). Multivariate analysis indicated that significant independent predictors of impacted stones were thicker UWT and lower HAB ratio (all P < 0.01). HAB ratio was a significant preoperative predictor of stone impaction in patients undergoing URSL for ureteral stones. HAB ratio may be informative for selecting the treatment and preoperative preparations.

Usefulness of Preoperative High Systemic Immune-Inflammation Index as a Prognostic Biomarker in Patients Who Undergo Radical Cystectomy for Bladder Cancer: Multicenter Analysis.

Evidence of the prognostic value of pretreatment systemic immune-inflammation index (SII) after radical cystectomy (RC) for bladder cancer is limited. This study aims to assess the association between preoperative SII and prognosis after RC for bladder cancer. In this multicenter retrospective study, we calculated preoperative SII as well as the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) in 237 patients who underwent RC for bladder cancer between March 2009 and March 2018. Patients were classified into high SII and low SII groups by using the optimal cutoff value (438 × 109/L) based on receiver operating characteristic curve analysis for cancer-specific death. We compared cancer-specific survival (CSS) and overall survival (OS) between the two groups. To evaluate the prognostic impact of preoperative SII, we also performed Cox proportional regression analyses for CSS and OS. Of 237 patients, 127 patients were classified into the high SII group and 110 patients into the low SII group. During the follow-up period, 70 patients died of bladder cancer (30%) and 21 patients died from other causes (9%). Patients with high SII had significantly lower rates of CSS and OS than those with low SII (p < 0.01 and p < 0.01, respectively). Multivariable Cox proportional hazard analysis showed that high SII was independently associated with poor CSS (p = 0.01) and poor OS (p < 0.01). In conclusion, high SII could be an independent significant predictor of poor prognosis after RC in patients with bladder cancer.

Myosteatosis as a novel prognostic biomarker after radical cystectomy for bladder cancer.

This study aims to evaluate the influence of myosteatosis on survival of patients after radical cystectomy (RC) for bladder cancer. We retrospectively identified 230 patients who underwent RC for bladder cancer at our three institutions between 2009 and 2018. Digitized free-hand outlines of the left and right psoas muscles were made on axial non-contrast computed tomography images at level L3. To assess myosteatosis, average total psoas density (ATPD) in Hounsfield Units (HU) was also calculated as an average of bilateral psoas muscle density. We compared cancer-specific survival (CSS) between high ATPD and low ATPD groups and performed cox regression hazard analyses to identify the predictors of CSS. Median ATPD was 44 HU (quartile: 39-47 Hounsfield Units). Two-year CSS rate in overall patients was 76.6%. Patients with low ATPD (< 44 HU) had significantly lower CSS rate (P = 0.01) than patients with high ATPD (≥ 44 HU). According to multivariate analysis, significant independent predictors of poor CSS were: Eastern Cooperative Oncology Group performance status ≥ 1 (P = 0.03), decreasing ATPD (P = 0.03), non-urothelial carcinoma (P = 0.01), pT ≥ 3 (P < 0.01), and pN positive (P < 0.01). In conclusion, myosteatosis (low ATPD) could be a novel predictor of prognosis after RC for bladder cancer.

Three-dimensional mean stone density on non-contrast computed tomography can predict ureteroscopic lithotripsy outcome in ureteral stone cases.

The association between mean stone density (MSD) and ureteroscopic lithotripsy outcome remains controversial. MSD automatically measured by 3D images of stones (3D-MSD) was recently reported to be more useful than manual measuring methods for predicting outcomes of shock-wave lithotripsy. This study aims to investigate whether 3D-MSD can predict ureteroscopic lithotripsy outcome. We retrospectively identified 218 patients who underwent ureteroscopic lithotripsy for kidney stones (n = 135) and ureteral stones (n = 83) between February 2011 and April 2017 with pretreatment non-contrast computed tomography (NCCT) at our hospital. Stone volume and 3D-MSD were automatically measured using high functional viewer. Logistic regression analysis was performed to identify factors contributing to treatment failure. Treatment failure was determined as residual fragments ≥ 4 mm using NCCT within 3 months after operation. Treatment failure rate was 20.1% (44/218 cases). Patients in treatment failure group had higher percentage of kidney stones (< 0.01) and multiple stones (p < 0.01), larger stone volume (p < 0.01) and higher 3D-MSD (p < 0.01). Multivariate analysis revealed that stone location (p < 0.01), stone number (p < 0.01), stone volume (p = 0.02) and 3D-MSD (p = 0.02) independently predicted the outcome. Categorized by stone location, 3D-MSD was the only significant independent predictor in cases of ureteral stones (p < 0.01), but was not significant in cases of kidney stones. 3D-MSD is useful for predicting ureteroscopic lithotripsy outcome in cases of ureteral stones.

Undifferentiated pleomorphic sarcoma of the prostate in a young man.

INTRODUCTION: Prostate sarcoma is an extremely rare disease with a poor prognosis. Undifferentiated pleomorphic sarcoma has never been described in the prostate.Case presentation: A 27-year-old man complained of frequent urination and dysuria for several years. Various examinations were suggestive of prostate sarcoma. The pathological diagnosis was confirmed as prostate sarcoma via ultrasound-guided transrectal needle biopsy. Because the location of the tumor in the prostate was confirmed by magnetic resonance imaging, we performed robot-assisted radical prostatectomy. The final pathological diagnosis was undifferentiated pleomorphic sarcoma. Local recurrence occurred at the front of the rectum 2 months after surgery. Although chemotherapy and radiotherapy were initially effective, he died 18 months after surgery. CONCLUSION: Undifferentiated pleomorphic sarcoma of the prostate is believed to have a poor prognosis. When selecting the surgical procedure, functionality should be considered for individual cases with complete resection.

Three-dimensional mean stone density measurement is superior for predicting extracorporeal shock wave lithotripsy success.

OBJECTIVES: The objective of the present study was to investigate the usefulness of three-dimensional images of stones to measure mean stone density for predicting the outcome of shock wave lithotripsy. METHODS: We retrospectively identified 239 patients who underwent shock wave lithotripsy with pretreatment non-contrast computed tomography. We automatically measured the mean stone density of three-dimensional images of stones using a high-functional viewer. For comparison, mean stone density was also measured by two previously reported techniques using both the abdominal windows and the bone windows on the axial slice at the level of the largest diameter of the stone. We compared the outcome predictive power after the first treatment with outcomes according to measurement by four other methods. We also carried out logistic regression analysis, including mean stone density measured by three-dimensional images. RESULTS: The single treatment success rate was 48.5%. The effect size (14.148) of the mean stone density measured by three-dimensional images was higher than those of the other four manual methods. In addition, the area under the curve (0.6330) of the mean stone density measured by three-dimensional images was significantly higher than those of the other methods. Increasing stone volume (P = 0.002) and increasing mean stone density measured by three-dimensional images (P = 0.023) were significant independent predictors of the treatment outcome on multivariate analysis. CONCLUSIONS: This is the first study to compare the predictive powers for shock wave lithotripsy outcome of various mean stone density measuring methods. There is an indication that mean stone density automatically measured by three-dimensional images of stones is more useful than other measuring methods for predicting outcomes of shock wave lithotripsy.

Noncontrast Computed Tomography Parameters for Predicting Shock Wave Lithotripsy Outcome in Upper Urinary Tract Stone Cases.

Kidney stones are a major public health concern with continuously increasing worldwide prevalence. Shock wave lithotripsy (SWL) is the first line treatment choice for upper urinary tract calculi with ureteroscopy and has advantages of safety and noninvasiveness, but the treatment success rate of SWL is lower than that of other therapies. It is therefore important to identify predictive factors for SWL outcome and select a suitable treatment choice for patients with upper urinary tract calculi. In recent years, computed tomography (CT) has become the gold standard for diagnosis of upper urinary tract calculi. Several factors based on CT images, including skin-to-stone distance, mean stone density, stone heterogeneity index, and variation coefficient of stone density, have been reported to be useful for predicting SWL outcome. In addition, a new method of analysis, CT texture analysis, is reportedly useful for predicting SWL outcomes. This review aims to summarize CT parameters for predicting the outcome of shock wave lithotripsy in stone cases in the upper urinary tract.