Role of simulation in kidney stone disease:A systematic review of literature trends in the 26 years

BACKGROUND Minimally invasive techniques for treatment of urinary stones requires expertise,experience and endoscopic skills.Simulators provide a low-stress and low-risk environment while providing a realistic set-up and training opportunities.AIM To report the publication trend of‘simulation in urolithiasis’over the last 26 years.METHODS Research of all published papers on“Simulation in Urolithiasis”was performed through PubMed database over the last 26 years,from January 1997 to December 2022.Papers were labelled and divided in three subgroups:(1)Training papers;(2)Clinical simulation application or surgical procedures;and(3)Diagnostic radiology simulation.Each subgroup was then divided into two 13-year time periods to compare and identify the contrast of different decades:period-1(1997-2009)and period-2(2010-2022).RESULTS A total of 168 articles published on the application of simulation in urolithiasis over the last 26 years(training:n=94,surgical procedures:n=66,and radiology:n=8).The overall number of papers published in simulation in urolithiasis was 35 in Period-1 and 129 in Period-2,an increase of+269%(P=0.0002).Each subgroup shows a growing trend of publications from Period-1 to Period-2:training papers+279%(P=0.001),surgical simulations+264%(P=0.0180)and radiological simulations+200%(P=0.2105).CONCLUSION In the last decades there has been a step up of papers regarding training protocols with the aid of various simulation devices,with simulators now a part of training programs.With the development of 3D-printed and high-fidelity models,simulation for surgical procedure planning and patients counseling is also a growing field and this trend will continue to rise in the next few years.

Appropriate kidney stone size for ureteroscopic lithotripsy:When to switch to a percutaneous approach

Flexible ureteroscopy(f URS) has become a more effective and safer treatment for whole upper urinary tract stones. Percutaneous nephrolithotomy(PNL) is currently the first-line recommended treatment for large kidney stones ≥ 20 mm and it has an excellent stone-free rate for large kidney stones. However, its invasiveness is not negligible considering its major complication rates. Staged f URS is a practical treatmentfor such large kidney stones because f URS has a minimal blood transfusion risk, short hospitalization and few restrictions on daily routines. However, as the stone size becomes larger, the stone-free rate decreases, and the number of operations required increases. Therefore, in our opinion, staged f URS is a practical option for kidney stones 20 to 40 mm. Miniaturized PNL combined with f URS should be considered to be a preferred option for stones larger than 40 mm. Moreover, URS is an effective treatment for multiple upper urinary tract stones. Especially for patients with a stone burden < 20 mm, URS is a favorable option that promises a high stone-free rate after a single session either unilaterally or bilaterally. However, for patients with a stone burden ≥ 20 mm, a staged operation should be considered to achieve stone-free status.

Bilateral hematoma after tubeless percutaneous nephrolithotomy for unilateral horseshoe kidney stones:A case report

BACKGROUND Bilateral perirenal hematoma is rarely reported in endoscopic management of horseshoe kidney stones,and there are few studies reporting the formation of bilateral hematoma following tubeless percutaneous nephrolithotomy(PCNL)for unilateral horseshoe kidney calculi.CASE SUMMARY A 32-year-old man was admitted to our hospital because of repeated intermittent hematuria for 10 years.Plain abdominal computed tomography(CT)scan revealed calculi in the horseshoe kidney;the largest being 2 cm in diameter.Tubeless PCNL was performed to remove the stones.Three days after the operation,the patient was discharged in a stable situation.Three days after discharge,the patient presented to our emergency department because of right low back pain and vomiting.Emergent CT scan revealed subcapsular and perirenal hematocele and exudates in both kidneys.Ultrasound-guided puncture and drainage of perirenal effusion were performed.After the temperature stabilized,the patient received low-pressure injection of urokinase 100000 U for 3 d.His routine blood indexes and the renal function returned to normal in 3 wk.CT re-examination 3 mo after lithotripsy showed that the subcapsular and perirenal hematoma and exudates in both kidneys were significantly absorbed as compared with those before.The patient was followed up for 1 year,during which no flank pain or hematuria recurred.CONCLUSION This is the first case report on the formation of bilateral hematoma following tubeless PCNL for unilateral horseshoe kidney calculi.

Education and training evolution in urolithiasis:A perspective from European School of Urology

Objective:With the worldwide increase in urolithiasis prevalence,the present study aimed to delineate and summarise recent evolutions in training for the management of urolithiasis.Methods:A PubMed search using the key words“simulation”,“training”,“ureteroscopy”,“RIRS”,“URS”,“percutaneous nephrolithotomy”,“PCNL”,“virtual reality”,“augmented reality”,“artificial intelligence”,“healthcare”,“curriculum”,and“assessment”was used to examine how education and training in urolithiasis have adapted over recent years.Focus was placed on the role of high-and low-fidelity simulation models,virtual reality and artificial intelligence,and standardised assessment and curriculum.Results:This review supports the necessity to incorporate technology,simulation,and other skill enhancement training modalities into surgical training.However,these cannot solely replace mentored training with an experienced professional supervisor.Whilst technological and simulation advancements are likely to prove increasingly important in urolithiasis training,it is just as important for stratification of robust curricula with validated assessment.We also propose a pathway for future training.Conclusion:Endourology subspeciality training programmes have successfully incorporated simulation model-based training for skill acquisition,refinement,and improving operative outcomes.Success is achieved by maintaining a delicate balance between machine and in person mentor-based training.A trainee-centred model that follows the proposed curriculum could aid this balance for the future generation of trainees.

Role of virtual reality in improving the spatial perception of the kidney during flexible ureteroscopy:A feasibility study using virtual reality simulators and 3D models

Background:The aims were to describe a software-based reconstruction of the patient-specific kidney cavity intraluminal appearance via a head-mounted device and to estimate its feasibility for training novices.Materials and methods:In total,15 novices were recruited.Each novice was shown a three-dimensional reconstruction of a patient's computed tomography scan,whose kidney was printed.They then joined the surgeon in the operating room and assisted them in detecting the stone during flexible ureteroscopy on the printed model.Then,each participant did a 7-day virtual reality(VR)study followed by virtual navigation of the printed kidney model and came to the operating room to help the surgeon with ureteroscope navigation.The length of the procedure and the number of attempts to find the targeted calyx were compared.Results:With VR training,the length of the procedure(p=0.0001)and the number of small calyces that were incorrectly identified as containing stones were significantly reduced(p=0.0001).All the novices become highly motivated to improve their endourological skills further.Participants noticed minimal values for nausea and for disorientation.However,oculomotor-related side effects were defined as significant.Five specialists noticed a good similarity between the VR kidney cavity representation and the real picture,strengthening the potential for the novice's education via VR training.Conclusions:Virtual reality simulation allowed for improved spatial orientation within the kidney cavity by the novices and could be a valuable option for future endourological training and curricula.

Indications and contraindications for shock wave lithotripsy and how to improve outcomes

For over 35 years shock wave lithotripsy has proven to be an effective,safe and truly minimally invasive option for the treatment of nephrolithiasis.Various technical factors as well as patient selection can impact the success of the procedure.We used published work focusing on outcomes of shock wave lithotripsy,risk of complications,and strategies for improving stone fragmentation to create this review.Multiple patient and technical factors have been found to impact success of treatment.Skin to stone distance,stone density and composition,size and location of the stone within the urinary system all influence stone free rates.A slower rate with a gradual increasing voltage,precise targeting,proper coupling will improve stone fragmentation and decrease risk of complications.The selection of appropriate patients through a shared decision making process and attention to the technical factors that improve stone free rates is key to providing an effective treatment and patient satisfaction.

Role of insulin resistance in uric acid nephrolithiasis

Metabolic syndrome has been implicated in the pathogenesis of uric acid stones.Although not completely understood,its role is supported by many studies demonstrating increased prevalence of uric acid stones in patients with metabolic syndrome and in particular insulin resistance,a major component of metabolic syndrome.This review presents epidemiologic studies demonstrating the association between metabolic syndrome and nephrolithiasis in general as well as the relationship between insulin resistance and uric acid stone formation,in particular.We also review studies that explore the pathophysiologic relationship between insulin resistance and uric acid nephrolithiasis.

Point Injection for Treating Nephritic Colic

Since 1994, the authors have treated 101 cases of nephritic colic by point injection therapy and achieved good curative results. Of them, 70 cases were diagnosed as having renal or ureteral calculi confirmed by abdominal X-ray and B-ultrasonic examination; and the others had the following symptoms: 1) sudden onset; 2) angina in unilateral lumbar and abdominal regions; 3) percussion-induced pain in the ipsilateral kidney region; and 4) erythrocytes or visible blood in urine found by laboratory test.

Advances in percutaneous stone surgery

Treatment of large renal stones has changed considerably in recent years.The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before,and this has been met with improvements in percutaneous stone surgery.In this review paper,we examine recent developments in percutaneous stone surgery,including advances in diagnosis and preoperative planning,renal access,patient position,tract dilation,nephroscopes,lithotripsy,exit strategies,and post-operative antibiotic prophylaxis.

Effects of lemon-tomato juice consumption on crystal formation in the urine of patients with calcium oxalate stones:A randomized crossover clinical trial

Background:Dietary supplementation with citrate-containing juices may serve as an effective alternative to potassium citrate therapy for preventing calcium oxalate stone recurrence.This study was performed to evaluate whether consumption of lemon-tomato juice can decrease the tendency for stone formation in the urine of calcium oxalate stone formers.Materials and methods:The study was conducted as a prospective interventional randomized crossover clinical trial with a repeated-measures design.Twenty-two patients with calcium oxalate stones and no metabolic abnormalities in the urine treated with lithotripsy at a tertiary care center from August 2017 to July 2018 were recruited.After a 14-hour overnight fasting,urine samples were collected after the patients consumed either milk only or milk and lemon-tomato juice.Their urine was tested for multiple parameters,including urine pH,specific gravity,calcium-creatinine ratio,and supersaturation with sodium oxalate,followed by optical density measurement via spectrophotometry.Results:There were no significant differences in the background characteristics between the 2 groups.The optical density of the urine samples obtained after consumption of milk only was significantly higher than that after consumption of milk and lemon-tomato juice(mean=0.131 for milk only vs.0.053 for milk and lemon-tomato juice,p<0.001).The urine calcium-creatinine ratio was similar between the groups(mean=0.141 for milk only vs.0.076 for milk and lemon-tomato juice,p=0.019).Conclusions:The addition of lemon-tomato juice as a source of citrate in the diet significantly decreases the established risk factors for calcium oxalate stone formation in patients.This study was prospectively registered at CTRI under number CTRI/2017/04/008312 on April 7,2017.

Splenic hamartoma: case report and review of literature

Splenic hamartoma is a benign malformation composed of an anomalous mixture of normal splenic elements.1 Approximately half of the patients with the tumor are asymptomatic and diagnosed accidentally by autopsy or splenectomy. The tumor-related renal hematological and dermatological abnormalities can be treated by removal of the tumor. Splenic hamartoma which is related to renal diseases including extramembranous glomerulonephritis, membranoproliferative glomerulonephritis and renal adenocarcinoma has been reported previously.

Acute toxicity study of Aspidopterys obcordata aqueous extract in Sprague-Dawley rats

OBJECTIVE: To examine the acute toxicity of an aqueous extract of Aspidopterys obcordata(A. obcordata) in Sprague Dawley rats.METHODS: The rats were orally administered a dose of 5000 mg/kg body weight and observed continuously for 6 h and then daily for 14 days. Control rats were administered distilled water. The effect of the extract on general behavior, body weight, and food and water intake were measured.After 14 days, the rats were sacrificed and their organs(liver, heart, spleen, lungs, kidney, adrenal glands, ovaries, and testes) were removed for macroscopic examination. The body and organ weights in addition to hematology(e.g., hemoglobin and white blood cell counts) and clinical blood biochemistry(e.g., albumin and bilirubin) were also examined.RESULTS: There were no deaths recorded, and the rats treated with A. obcordata showed no signs of toxicity. All measured parameters in rats treated with A. obcordata were unaffected when compared with those in control rats. The acute toxicity(LD_(50))was estimated to be > 5000 mg/kg body weight.CONCLUSION: Our results demonstrate the safety of an acute oral administration of an aqueous extract of A. obcordata in rats and indicate that future subacute and long-term toxicity testing of A. obcordata is warranted.

Clinical Study on the Treatment of Renal Colic by Body and Auricular Acupuncture

Objective： To evaluate the clinical effects of combined acupuncture and ear-puncture in treating renal colic. Methods： Sixty subjects were randomized into an acupuncture group and a medication group, 30 in each, to receive acupuncture and Western medicine respectively. The analgesic effects and pain relief time were measured in both groups. Results： Both of the two groups got pain relieved or reduced. The total effective rate was 89.7% in the acupuncture group, significantly superior to 77.4% in the medication group （P〈0.05）. Conclusion： Combined body and auricular acupuncture is efficient in relieving pain in treating renal colic, and its effective rate was higher compared with medication treatment.

Oxalate contents of commonly used Chinese medicinal herbs

OBJECTIVE:To assess the total and soluble oxalate contents of commonly used Chinese medicinal herbs.METHODS:Twenty-two Chinese medicinal herbs were extracted in both acid and water prior to determination of total and soluble oxalate,respectively.Oxalate was assayed in herbal extracts using a well-established enzymatic procedure.RESULTS:Among the 22 medicinal herbs,there was significant variation in oxalate content;Houttuynia cordata contained the highest amount of soluble oxalate(2146 mg/100 g) and Selaginella doederleinii contained the lowest amount(71 mg/100g).CONCLUSION:The results indicated that different Chinese medicinal herbs,even from the same family,contain significantly different amounts of oxalate.In susceptible individuals,the use of medicinal herbs with the highest oxalate contents could increase risk of kidney stone formation.

Survey on Acupuncture Treatment of Urinary Calculus and Renal Colic

Analyzed 74 articles relevant to urinary calculus and renal colic. The statistics found that the commonly used therapies were needling, acupuncture and moxibustion, electro-acupuncture, acupoint-injection, ear-point application, ear acupuncture, wrist-ankle acupuncture, scalp acupuncture, acupressure and combined acupuncture methods. The common acupoints that were used over 1,400 times in more than 12 articles were Shenshu (BL 23), Sanyinjiao (SP 6), Zusanli (ST 36), Zhongji (CV 3), and Jingmen (GB 25). Key Words Urinary Calculi - Kidney Calculi - Acupuncture-Moxibustion - Review Literature Author: HUANG Qin-feng (1952-), female, associate professorTranslator: XIAO Yuan-chun