Stone Density Research Articles

Ancient Maya Embedded Economies and Changing Ground Stone Densities in Households at Actuncan, Belize

In embedded economies where multiple modes of production and exchange exist, artifact distributions in households alone do not reflect the strength of specific modes. We use a diachronic perspective tied to changes in political economies and artifact class densities standardized by excavation volume at the Maya site of Actuncan, Belize, to elucidate changes in the strength of individual production and exchange modes in the Preclassic and Classic periods. We focus on ground stone densities as a measure of grinding intensity across elite and common households. Data indicate that common households always ground more maize than elites, but intensity peaked in the Late Classic when tax and tribute demands and market exchanges were greatest. In the Terminal Classic, common household grinding intensity decreased by half as tribute burdens diminished, illustrating the impact of political hierarchies on household economies.

Влияние эндовидеоскопических операций при нефролитиазе на функциональное состояние почек

Introduction. In recent years, there has been a persistent trend towards an increase in the incidence of urolithiasis. The treatment of large and complex kidney stones greatest difficulty is one of the challenges. Such stones, as well as surgical methods of their removal, can have an adverse effect on the functional state of the kidneys, which confers a significant medical, social and economic problem. The purpose of this study is to identify factors affecting the functional state of the kidneys in the postoperative period when using various video endoscopic methods of surgical treatment of patients with large and complex kidney stones. Materials and methods. We analyzed the results of treatment of 97 patients with large and complex kidney stones. Depending on the treatment, all these patients were divided into three groups: 1st – 44 (45,36%) patients who underwent percutaneous nephrolithotripsy in prone position, 2nd – 29 (29,9%) patients who underwent percutaneous nephrolithotripsy in the supine position, 3rd – 24 (24,74%) of the patient who underwent pyelolithotomy with laparoscopic and retroperitoneoscopic approaches. Assessment of the area and density of stones was performed by computed tomography. The glomerular filtration rate (GFR) was calculated by CKD-PI formula and dynamic nephroscintigraphy was used to assess of each kidney function. Results. In the postoperative period, the decrease in GFR was most pronounced in the group of patients after percutaneous nephrolithotripsy in the supine position. Among the most significant factors worsening this indicator were the volume of intraoperative (r=0,410, p<0,001, n=97) and postoperative blood loss (r=0,294, p <0.01, n=97), duration of surgery (r=0,187, p <0,1, n=97), density (r=0,426, p <0,001, n=97) and the area (r=0,554, p <0,001, n=97) of the concretion, as well as the body mass index (r=0,294, p <0,01, n=97). Conclusions. The most significant factors that have a negative impact on the functional state of the kidneys were the density and area of the stone, the patient's body mass index and the volume of intraoperative blood loss. The least deterioration of kidney function in the postoperative period was observed with endoscopic pyelolithotomy, and the greatest – with percutaneous nephrolithotripsy in the patient's back position.

Safety and Efficacy of Flexible Ureterorenoscopy Surgery: Results of Our Large Patient Series.

Introduction: The aim of our study is to evaluate the success rates of our retrograde intrarenal surgery operations and the complications we encountered and to determine in which kidney segment the operations were more successful with flexible ureterorenoscopy.Methods: The records of retrograde intrarenal surgery operations performed between March 2013 and January 2021 in Health Sciences University, Adana City Training and Research Hospital, urology clinic were analyzed retrospectively. Patients’ age, body mass index, operation side, stone size, stone density, duration of operation, first-day and first-month operation success status, presence of preoperative and postoperative ureteral stent, preoperative and postoperative first-day and first-month creatinine levels, and preoperative and postoperative first-day and first-month hematocrit levels were recorded.Results: Our study consisted of a total of 1128 patients, 618 males (54.7%) and 510 (45.2%) females, with an average age of 42.3±14.4. Kidney stones were most commonly found in the renal pelvis (54.2%). The postoperative first-day success rate was highest in the pelvis stone group (P=0.009). The first month’s success rates were highest in those with pelvic stones (93.1%), and the lowest in patients with multiple stones (85.7%). Patients’ operation time, postoperative hematocrit and creatinine levels, and complications did not differ statistically between the groups (P>0.05).Conclusion: Retrograde intrarenal surgery is an acceptable minimally invasive and effective surgery with low complication rates. There is a high success rate, especially in pelvis stones.

Contribution of Ureteral Access Sheath Use to the Efficacy of Semirigid Ureterorenoscopy in Upper Ureteral Stones Smaller than 2 cm: Experiences of a Single Center

Objective: The aim of our paper is to answer the question that during the ureteroscopy procedure if ureteral access sheath could facilitate operation, could decrease complication rates,operation time,requirement of additional surgery. Method: The patients were randomly divided into two groups. Group 1 contained 44 patients for whom a UAS was not used and Group 2 consisted of 70 patients for whom a UAS was used during the URS procedure. The operation was continued using the semirigid ureteroscope within the UAS. Results: There were no statistically significant differences between the two groups in terms of the mean age, BMI, ASA score, mean stone density, previous unsuccessful interventions, history of stone disease, mean grade of hydronephrosis in renal pelvis and mean stone size. the mean operation time was 41 minutes for Group 1 and 30 minutes for Group 2, with a statistically significant difference (p < 0.001), consistent with the literature. Similarly, the difference in the mean fluoroscopy time was statistically significant, being determined as six minutes for Group 1 and three minutes for Group 2 (p < 0.001). Conclusions: Use of UAS was statistically significantly superior in terms of many parameters, such as increased stone-free rate, shorter operation time, and reduced requirement of additional surgery. Furthermore, the complication rates did not significantly differ between the UAS and non-UAS groups. We also consider that the advantages of a higher stone-free rate and reduced requirement of secondary interventions make the cost of UAS acceptable.

A novel model using computed tomography parameters to predict shock wave lithotripsy success in ureteral stones at different locations

ObjectiveTo combine non-contrast computerized tomography (NCCT)-based parameters with stone and patient characteristics that are already known to affect shock wave lithotripsy (SWL) success and assess this novel model’s effectiveness in predicting SWL success for single ureteral stones in different locations. Materials and methodsData of patients treated by SWL for a single ureteral stone between January 2017 and January 2019 were retrospectively reviewed. Demographic parameters of patients and stone characteristics were combined with NCCT-based parameters. NCCT-based parameters included the presence or absence of hydronephrosis, perinephric stranding, periureteral edema, diameter of the proximal ureter, ureteral wall thickness (UWT) at ureteral stone site. The logistic regression method was used for the development of a useful predictive model. Subsequently, the receiver operating curve was used to determine cut-off levels, and a scoring system was developed for prediction of SWL success. ResultsStone-free rate was 77,1% (267/346) in the entire cohort. Univariate analysis revealed that age, stone volume, density, perinephric stranding, diameter of proximal ureter, and UWT, were associated with SWL success. In multivariate analysis, proximal ureteral stone location, stone volume, density, and UWT were independent predictors of SWL success. The formula used during logistic regression analysis was: 1/[1 + exp {−8.856 + 0.008 (stone volume) + 0.002 (stone density) + 0.673 (UWT) + 1026 (proximal ureteral stone)}]. The scores of 0, 1, 2, 3 and 4 were associated with 97,8%, 83,4%, 60,8%, 33,2% and 11,1% success rates, respectively, in the prediction model based on these parameters. ConclusionWe conclude that our model can facilitate decision-making for SWL treatment of ureteral stones in different locations.

Reducing the rate of negative ureteroscopy: predictive factors and the role of preoperative imaging.

The aim of this study was to investigate factors that may predict a negative ureteroscopy (URS) performed for ureteric calculi in prestented patients and to assess preoperative imaging in reducing the rate of negative URS. Data were collected on emergency stent placement for a ureteric calculus from April 2011 to February 2016 (Group A) and October 2016 to October 2019 (Group B). Data included patient demographics, indication for a stent, stone characteristics, baseline bloods, urine culture, readmission, negative URS rate and the use of pre-URS imaging. Multivariate logistic regression was used for statistical analysis. Of 257 patients who underwent emergency stent insertion, 251 underwent deferred URS for a ureteric calculus and 6 avoided URS due to pre-URS imaging. Indications for stent were pain (42%), sepsis (39%) and acute kidney injury (19%). Mean stone size was 7.8mm, mean stone density was 699 Hounsfield units (HU) and the stone locations were upper (62%), mid (13%) and lower ureter (25%). The overall negative URS rate was 12%. The negative URS rate was lower in patients with pre-URS imaging compared with those with none, 6% and 14%, respectively (OR=2.33, 95% CI: 0.69-7.56, p=0.2214). Logistic regression analysis indicated stone size as the only significant predictor of a negative URS, where the greater the size of the stone the less likely URS would be negative (β=0.75, 95% CI: 0.60-0.94 p=0.011). Utilising pre-URS imaging can lead to a reduction in negative URS rate. Stone size <5mm appears to be the subgroup most likely to benefit from imaging.

Surgical removal of bladder stone in a sulcata tortoise (Centrochelys sulcata): A case study

A 2 years old male sulcata (Centrochelys sulcata) tortoise presented to the clinic with problems of refuse to eat for 2 weeks, weaken, sleeping all day long and no defecated or urinating during last 1 week. The population is 24 tortoises in many species. Daily diets mainly on lettuce and cabbage. Clinical signs found during physical examination were closed eyelids, weakness and inactive. An X-ray imaging was presented and found a large white mass in urinary bladder. The diagnose was bladder stones or calculi vesicalis. Due to the size and the density of the bladder stones, a surgery intervention for bladder stones removal was conducted. Anesthesia using ketamine dose 30 mg/kg BW combine with xylazine dose 2 mg/kg BW injected intramuscularly. The surgery starts with cutting the plastron using a sterile dremel, opening the plastron and put the cutting plastron in saline water, opening the coelomic cavity by incising the abdominal muscles, finding the urinary bladder, incision the urinary bladder, removing the bladder stones, flushing the urinary bladder, suturing the urinary bladder, suturing the abdominal muscles, closing the plastron and applying the epoxy glue for covering the cutting plastron. Antibiotic enrofloxacine 10% with dose 5 mg/kg BW combine with antiinflamatory tolfenamic acid 4% and vitamin B complex all are injected intramuscularly once a day for 5 consecutive days. The tortoise was hospitalized and monitoring daily. The tortoise recover in day 4 after surgery, start eating and healing to normal activities in day 7.

Bilateral same-session flexible ureteroscopy for renal stones: a feasible method.

A staged ureteroscopic procedure is generally preferred to treat bilateral renal stones. In this study, we evaluated the feasibility of bilateral same-session flexible ureteroscopy (BS-fURS) in renal stones. A total of 81 patients underwent bilateral BS-fURS between March 2014 and March 2021 for bilateral renal stones. The mean stone burden per patient was 17±4 (range 7–27 mm). The average stone density was 1240 HU (970 to 1510). We used 4 types of ureteroscopes: Olympus URF-V2 (34 cases), Storz Flex X2 (30 cases), single-use PUSEN PU 3022 (12 cases), and single-use PUSEN – PU 3033A (5 cases). We specifically set our Holmium laser for dusting, pop-corning, and fragmenting. We found 31 calcium oxalate monohydrate cases, 11 calcium oxalate dehydrate cases, 17 uric acid cases, and 22 magnesium ammonium phosphate cases. The mean operating time was 77 min. (range 52 to 85) for both renal units. The SFRs were evaluated between 1 and 3 months with computed tomography (fragments >3 mm were defined as residual). Double J stenting (6Fr.) was applied bilaterally in 8 cases (9.87%) and unilateral in 34 cases (41.97%). The overall SFRs after 1 and 2 procedures were 81.48% (66/81 cases) and 92.59% (75/81 cases), respectively. Postoperative complications after an overall 96 procedures were Clavien I-II (18.75%) and Clavien III (3.12%). Urinary tract infections were observed in 13 cases (16.04%) without any case of urosepsis. Our experience suggested some BS-fURS advantages as a single anesthetic session and potentially reduced cost associated with treatment. BS-fURS seem feasible, especially for medium-sized bilateral renal stones in high-volume centers.

Predicting ESWL success by determination of Hounsfield unit on non-contrast CT is clinically irrelevant in children.

The necessity of determining stone density by non-contrast computerized tomography (NCCT) before extracorporeal shock wave lithotripsy (ESWL) is a controversial topic due to the radiation exposure. We aimed to investigate whether stone density is helpful in predicting the success of ESWL in pediatric patients or not. In this retrospective study, database of a single center was used to identify 232 children aged between 2 and 16years. Patients with abnormal renal anatomy, distal obstruction, a known cystine stone disease, a previous history of an intervention regarding stone, and an insufficient follow-up period (< 3months) were excluded from the study. A total of 209 patients were included in the study (94 with NCCT, 115 without NCCT). Groups were compared in terms of stone size, stone location, and stone-free rate at 3months after a single ESWL session. The mean age was 6.17 ± 3.27years and 120 (57.4%) of the patients were male and 89 (42.6%) were female. Mean stone size was 11.7mm in NCCT group and 12.3mm in non-NCCT group (p 0.128). The complete stone clearance rate in NCCT and non-NCCT group at 3months after ESWL was 57.4% (54/94) and 54.7% (63/115), respectively, and there was no statistically significant difference (p 0.316). In conclusion, unnecessary NCCT use should be avoided before ESWL considering the similar success rates after ESWL and the risk of exposure to radiation.

Extracorporeal shock wave lithotripsy for the treatment of urinary lithiasis in children

Introduction: Extracorporeal shock wave lithotripsy (ESWL) is an option for the treatment of urinary lithiasis.&#x0D; Objective: To describe the outcomes of ESWL for the treatment of urinary lithiasis in children.&#x0D; Methods: A descriptive and retrospective study of 51 patients with urinary lithiasis that underwent ESWL from 2014 to 2019.&#x0D; Results: Males and 15–18-year-old patients prevailed; 27.4% had prior surgery; 10-20 mm lithiasis of renal location and density between 400-799 HU were the most common; a double J stent was the most utilized urinary derivation prior to lithotripsy treatment; 7.8% required retreatment; 13.7% additional interventions; the stone-free rate was 74.5% at one month and 92.2% at three months. The size of the lithiasis was associated with the success of the treatment (p&lt;0.023). The most frequent complication was steinstrasse; endourologic procedures were the most utilized, grade III b (Clavien-Dindo) prevailed and were associated to older patients (p=0.04), renal lithiasis localization (p=0.017), larger size (p=0.08), and density(p=0.036).&#x0D; Conclusions: ESWL is effective and safe for treating urinary lithiasis in children. Its success was significantly associated to smaller stone size and its complications to patients of older age, larger stone size, density and renal localization of the lithiasis.

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ДОБАВКИ АКТИВНОГО КРЕМНЕЗЕМА НА СВОЙСТВА ВЯЖУЩИХ ЩЕЛОЧНОЙ АКТИВАЦИИ

The world experience of implementation and the uniqueness of building alkaline composites prove the prospects and relevance of the development of clinker-free technology. The development of formulations of alkaline activation binders based on fine powders of aluminosilicate nature will allow obtaining new effective and high-quality products. The paper investigates the effect of active microsilica on the kinetics of strength gain, changes in density and pore space of cement stone, formulation and technological factors and hardening conditions. The chemical transformations of active silica under alkaline conditions, leading to changes in the pH value, have been substantiated. By electron microscopy, the foundations of the formation of the structure of a cement stone on a binding bond "aspiration dust (60%) - clinker dust (40%) - microsilica - Na2SiO3" amorphous substance, calcium sulfoaluminates, calcium hydroaluminates are developed. According to authors, the research results are important for the construction industry, since the proposed formulations of clinker-free cements can replace expensive and energy-intensive Portland cement, making it possible to create strong and durable concrete and reinforced concrete structures

Retrograde intrarenal surgery: laser showdown (Ho:YAG vs thulium fiber laser).

Retrograde intrarenal surgery (RIRS) has always been recommended for large stones > 20 mm, using the Ho:YAG laser. The introduction of a new technology in the urological market, the thulium fiber laser (TFL) has revolutionized the endourology world because of its characteristics and significantly shorter laser-on time (LOT) and operative time, without scarifying the champ vision. The aim of this review is to evaluate the most relevant findings of the last 2 years of each laser technology, confronting Ho:YAG vs TFL, analyzing who is more suitable for performing an efficient RIRS. Five full clinical trials using TFL for RIRS were found. Median LOT was between 2.8 and 34 min. All stones were similar in terms of stone volume, >500 mm3, and stone density, > 800 HU. Low complication rate, mostly Clavien-Dindo grade I and II and not related to the laser itself. One clinical trial only analyzed the efficacy of TFL for > 20 mm renal stones. Based on this review, TFL performs a more efficient RIRS than the Ho:YAG laser with similar safety.

The clinical efficiency and safety of 60W superpulse thulium fiber laser in retrograde intrarenal surgery.

ABSTRACTIntroduction:Our aim is to evaluate the clinical efficiency and safety of 60W Thulium fiber laser (TFL) during retrograde intrarenal surgery (RIRS). The performance of the TFL across different ranges of stone volumes and stone densities is assessed.Materials and Methods:Between October 2019 and August 2020, a prospective study was done on 135 patients with < 20 mm renal stones, who underwent RIRS using TFL. Stone parameters, total laser time, total energy delivered (kJ), and fiber burn-back were recorded. Laser efficacy (J/mm3) and ablation speed (mm3/s) were calculated.Results:Data of 126 of 135 patients included in the study were analyzed. The mean patient age was 45.04 ± 12.30 years. Mean stone size was 15.19 ± 4.52 mm, and mean stone volume was 1061.85 ± 806.81 mm3. Mean laser time was 19.78 ± 12.32 min. At higher stone volume (>1000 mm3), J/mm3 decreased significantly from 16.18 ± 5.90 to 10.92 ± 3.21 (P < 0.001) and the ablation speed increased significantly (0.77 ± 0.28–1.04 ± 0.28 mm3/s [P < 0.001]). Stone density did not have a significant influence on the laser efficacy [B = -0.31 (-2.45 to 1.82, p=0.771)] or on the ablation speed [B = -0.06 (-0.17 to 0.05, p=0.278)]. Overall SFR was 93.6%. The complication rate was 16.6% (21/126). Out of the 21, 12 patients had hematuria and 9 had fever, which were of Clavien grades 1–2.Conclusion:Superpulse TFL is efficient and safe. The work efficiency increases for larger volume stones. The work efficiency remains the same across different stone densities. No complication more than Clavien grade 2 was encountered.

Efficacy of extracorporeal shockwave lithotripsy, with modified position of the machine head in the treatment of lower calyceal stones in obese patients.

Context:Extracorporeal shock wave lithotripsy (ESWL) has inferior results in the lower calyceal stones, especially in obese patients.Aims:This study aimed at evaluating of the efficacy of extracorporeal shockwave lithotripsy, with modified position of the machine head in the treatment of single lower calyceal stones in obese patients.Settings and Design:This was a prospective study (phase IV trial).Subjects and Methods:We studied the anterior rotation of the shock wave machine head in obese patients for the treatment of lower calyx stones. From February 2015 to June 2019, 105 obese patients (body mass index [BMI] ≥35) having lower calyx stones (≤20 mm) underwent ESWL at our institute. The procedure was done in a supine position, and the head of the shock-wave machine was tilted anteriorly. ESWL was considered successful if the kidney was completely cleared of stones.Statistical Analysis Used:The statistical methods used were descriptive statistics, mean, standard deviation frequency analysis, Chi-square test, unpaired t-test test, and Pearson correlations (r).Results:The mean BMI of these patients was 39.71 ± 2.8 kg/m2, the mean stone size was 17.4 ± 2.1 mm, the mean stone density was 767.1 ± 193.4 Hounsfield unit, and the mean of skin to stone distance (SSD) was 145.4 ± 4.5 mm. ESWL was successful in 86 (81.9%) patients; 13 patients (12.4%) showed complete success after the first session, while 37 (35.2%), 25 (23.8%), and 11 (10.5%) patients showed success after the second, third, and fourth sessions, respectively. ESWL failed in 19 (19.1%) cases. The success rate decreased significantly with higher stone density and SSD (P < 0.001), with negative correlations (r values) of −0.871 and −0.811, respectively.Conclusions:Anterior rotation of the head of the shock wave machine is a suitable option for the treatment of lower calyceal stones in obese patients.

Can the Stone Scoring Systems Be Used to Predict Infective Complications of Retrograde Intrarenal Surgery?

Objective: We aimed to evaluate whether the retrograde intrarenal surgery (RIRS) scoring systems (Resorlu-Unsal Stone Score [RUSS], modified Seoul National University Renal Stone Complexity Score [modified S-ReCS], and R.I.R.S. score) can predict the infective complications after RIRS. Subject and Methods: A total of 581 patients who underwent RIRS for kidney stones were included in the study. All patients were evaluated for demographic data, medical history, radiological imaging methods before surgery, duration of surgery, and hospitalization time after surgery. Stone laterality, stone burden, stone size, stone density, the number of stones, stone localization, the presence of congenital kidney anomaly, and solitary kidney were evaluated preoperatively by computed tomography. The RUSS and modified S-ReCS and R.I.R.S. score of all patients were determined. Results: Infective complications were detected in 47 (8.1%) patients who underwent RIRS. Fever developed in 27 subjects (4.6%), urinary infection in 15 (2.5%), sepsis in 2 (0.3%), and septic shock in 3 (0.5%) patients. In multivariate logistic regression analysis, age (OR = 1.8; 95% CI = 1–3.4; p = 0.049), surgical duration of >60 min (OR = 1.9; 95% CI = 1.1–3.5; p = 0.027), and high R.I.R.S score (OR = 8.9; 95% CI = 1.9–42.4; p = 0.006) were shown to be independent risk factors for the infective complications after RIRS. A receiver operating characteristic curve analysis showed that the R.I.R.S. score can be used as a marker to predict infective complications (AUC = 0.619, CI = 0.55–0.69; p = 0.007). Conclusion: We suggest that the R.I.R.S. score can be used to predict infective complications in RIRS.

Predictive value of hounsfield unit in urinary system stones applied with eswl

This study claims to examine the relationship between the Housfield unit (HU) value and the success of Electro Shock Wave Lithotripsy (ESWL) treatment. Data of 142 patients were evaluated retrospectively in this cross-sectional observational study. The threshold value for stone density is calculated as 991.20 HU in the ROC analysis. The patients are seperated into two groups with respect to this value, and their demographic characteristics, stone characteristics and success rates after ESWL treatment are statistically compared. For the variables that are statistically crucial in the univariate analysis, logistic regression analysis are used as a multivariate analysis. The mean age of all patients were 45.25±11.72 years and the mean body mass index (BMI) is 28.42±3.98 kg/m2. While our stone-free rate was 66.2% in our study, the mean stone size was 11.25±3.83mm, the Hounsfield unit value was 1007.55±337.75 HU, and the stone-skin distance was 108.02±20.02mm, respectively. We observed a crucial difference in between the Housfield unit value and stone size in univariate and multivariate analyzes between the two groups, and the stone-free rate after ESWL. The Hounsfield unit value, measured by the non-contrast computed tomography method, is a parameter for the prediction in success of patients undergoing Electro Shock Wave Lithotripsy treatment. Also, stone density above 991.20 HU in patients having urinary system stone disease requires the evaluation of alternative treatments as a condition that reduces the success of the treatment.

Can Computerized Hounsfield Unit Estimation Be Used as Predictor for Ureteric Stone Localization by Fluoroscopy during Extra Corporal Shock Wave Lithotripsy and Ureteroscopy?

Current minimally invasive interventions for ureteric stones involve either ESWL or Ureteroscopy and stone localization is mandatory for successful treatment in both. Objectives: To avoid doing KUB radiograph before ESWL routinely by correlating the stone attenuation value on CT KUB with stone visualization at fluoroscopy. Methods: This is a prospective cross sectional hospital based, Multicentric study carried out on 1010 patients with ureteric stones in Sudan from August 2014 to March 2016. Results: Mean stone density in HU was 704.45 ± 300 (SD) ranging (81 - 1873) HU. All of the stones were localized using fluoroscopy and only 26.5% of them were not seen under fluoroscopy. I.V contrast was used mostly, and also mainly in the upper ureter. More than 80% of the application of contrast through the ureteric catheter was in the lower ureteric stones. 91.2% of patients with stone density ≤ 400 HU failed to appear at fluoroscopy and therefore 400 HU attenuation value can be used as a cut-off level to request doing KUB before ESWL and Ureteroscopy. Conclusion: the ureteric stones with density ≤400 HU the likelihood of being non-visualized at fluoroscopy is 91.2% therefore if the stone has ≤400 HU at CT KUB it is mandatory to do KUB before treatment above that it is most likely to be seen at fluoroscopy and no need to request KUB for them before ESWL or URS. 1) Inclusion Criteria: All patients diagnosed by CT scan to have ureteric stones for ESWL or Ureteroscopy. 2) Exclusion Criteria: Patients for whom treatment of ureteric stone by ESWL or ureteroscopy is not indicated like severe infection or poor kidney function where nephrectomy is needed.

Factors affecting use of flexible ureteroscope in large renal stones; stone size or stone composition.

After advances in flexible ureteroscopes' design, accessories, and lithotripters, flexible ureteroscope has been used widely for the treatment of large renal calculi >2 cm. The objective was to evaluate the role of flexible ureteroscopy with laser lithotripsy in the treatment of large renal calculi >2 cm and find out which factor can affect the results. Prospectively, we have studied 47 patients who have passed through flexible ureteroscopy with laser lithotripsy for renal calculi >2 cm. Preoperative, operative, and postoperative data were recorded. Results and complications were recorded, too. In 47 patients, the mean stone size is 26.2 ± 4.1 cm and the total stone-free rate (SFR) is 89.4%, while in stone size ≤3 cm, the SFR is 90.7%, and for stone size >3 cm, the SFR is 75%. Overall stone density is 1020 ± 286 HU. The SFR is 95.5% in stones ≤1000 HU and 84% in stones >1000 HU. The mean operative time is 99.2 ± 29.3 min. The intraoperative complications are 17%, while postoperative complications are 36% and all complications are mild. Flexible ureterorenoscopy (FURS) is safe and effective for the treatment of large renal calculi >2 cm. Stones >3 cm may have lower results even after staged therapy.

Экстракорпоральная ударно-волновая литорипсия: эволюция, показания, противопоказания и осложнения

Extracorporeal shockwave lithotripsy has proved to be an effective, safe and minimally invasive method oftreatment of urolithiasis for four decades. Despite the rapid improvement of endourological equipment, ESWLis still relevant today and is considered to be the main treatment method for urolithiasis in many guidelines.In search of more in-depth information about the history of this method, clinical application, limitations andpossible complications, we analyzed such foreign sources as PubMed, Embase, Medline, e-library. Accordingto the data obtained, it was found that numerous factors related to the patient and the technique influencethe success of treatment. The distance from the skin to the stone, stone density and composition, size andlocation of the stone in the urinary system all affect the frequency of “stone-free”. A slower speed with a gradualincrease in tension, precise pointing, and proper connection help to improve stone fragmentation and reducethe risk of complications.

The First 100 Cases of Endoscopic Combined Intrarenal Surgery in Korea: Matched Cohort Analyses versus Shock-Wave Lithotripsy.

PurposeThis study presents our initial experience with endoscopic combined intrarenal surgery (ECIRS) for large renal stones and compares the results of a propensity score-matched cohort of patients undergoing shock-wave lithotripsy (SWL).Materials and MethodsA total of 100 adults underwent ECIRS for renal stones between August 2017 and January 2019. For comparison, 2172 patients who underwent a first session of SWL between January 2005 and May 2018 were included in the SWL cohort. Propensity score matching was performed using maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) scores. Stone-free rate (SFR) and success rate were compared between ECIRS and SWL.ResultsIn the ECIRS group, the mean MSL, mean MSD, and mean SHI were 28.7±15.2 mm, 1013.9±360.0 Hounsfield units (HU), 209.4±104.0 HU, respectively. The SFR was 70%, and the success rate was 82.0% in this group. Although the ECIRS group had larger, harder, and more homogeneous stones than the SWL group, ECIRS showed a higher SFR and success rate than SWL. After propensity-score matching, SFR and success rate remained higher with ECIRS than with SWL (both, p<0.001). In multivariate logistic regression, smaller stone size [odds ratio (OR): 0.947, 95% confidence interval (CI): 0.913–0.979, p=0.002] and lower Seoul National University Renal Stone Complexity score (OR: 0.759, 95% CI: 0.610–0.935, p=0.011) were independent predictors of successful ECIRS.ConclusionECIRS showed a higher SFR and success rate than SWL for large renal stones. Smaller stone size and lower complexity of stones were associated with a higher likelihood of successful ECIRS.