Possible complications of ureteroscopy in modern endourological era: two-point or "scabbard" avulsion

Management of urinary stones: state of the art and future perspectives by experts in stone disease

AIM

To present state of the art on the management of urinary stones from a panel of globally recognized urolithiasis experts who met during the Experts in Stone Disease Congress in Valencia in January 2024. Options of treatment: The surgical treatment modalities of renal and ureteral stones are well defined by the guidelines of international societies, although for some index cases more alternative options are possible. For 1.5 cm renal stones, both m-PCNL and RIRS have proven to be valid treatment alternatives with comparable stone-free rates. The m-PCNL has proven to be more cost effective and requires a shorter operative time, while the RIRS has demonstrated lower morbidity in terms of blood loss and shorter recovery times. SWL has proven to be less effective at least for lower calyceal stones but has the highest safety profile. For a 6mm obstructing stone of the pelviureteric junction (PUJ) stone, SWL should be the first choice for a stone less than 1 cm, due to less invasiveness and lower risk of complications although it has a lower stone free-rate. RIRS has advantages in certain conditions such as anticoagulant treatment, obesity, or body deformity. Technical issues of the surgical procedures for stone removal: In patients receiving antithrombotic therapy, SWL, PCN and open surgery are at elevated risk of hemorrhage or perinephric hematoma. URS, is associated with less morbidity in these cases. An individualized combined evaluation of risks of bleeding and thromboembolism should determine the perioperative thromboprophylactic strategy. Pre-interventional urine culture and antibiotic therapy are mandatory although UTI treatment is becoming more challenging due to increasing resistance to routinely applied antibiotics. The use of an intrarenal urine culture and stone culture is recommended to adapt antibiotic therapy in case of postoperative infectious complications. Measurements of temperature and pressure during RIRS are vital for ensuring patient safety and optimizing surgical outcomes although techniques of measurements and methods for data analysis are still to be refined. Ureteral stents were improved by the development of new biomaterials, new coatings, and new stent designs. Topics of current research are the development of drug eluting and bioresorbable stents. Complications of endoscopic treatment: PCNL is considered the most invasive surgical option. Fever and sepsis were observed in 11 and 0.5% and need for transfusion and embolization for bleeding in 7 and 0.4%. Major complications, as colonic, splenic, liver, gall bladder and bowel injuries are quite rare but are associated with significant morbidity. Ureteroscopy causes less complications, although some of them can be severe. They depend on high pressure in the urinary tract (sepsis or renal bleeding) or application of excessive force to the urinary tract (ureteral avulsion or stricture). Diagnostic work up:  Genetic testing consents the diagnosis of monogenetic conditions causing stones. It should be carried out in children and in selected adults. In adults, monogenetic diseases can be diagnosed by systematic genetic testing in no more than 4%, when cystinuria, APRT deficiency, and xanthinuria are excluded. A reliable stone analysis by infrared spectroscopy or X-ray diffraction is mandatory and should be associated to examination of the stone under a stereomicroscope. The analysis of digital images of stones by deep convolutional neural networks in dry laboratory or during endoscopic examination could allow the classification of stones based on their color and texture. Scanning electron microscopy (SEM) in association with energy dispersive spectrometry (EDS) is another fundamental research tool for the study of kidney stones. The combination of metagenomic analysis using Next Generation Sequencing (NGS) techniques and the enhanced quantitative urine culture (EQUC) protocol can be used to evaluate the urobiome of renal stone formers. Twenty-four hour urine analysis has a place during patient evaluation together with repeated measurements of urinary pH with a digital pH meter. Urinary supersaturation is the most comprehensive physicochemical risk factor employed in urolithiasis research. Urinary macromolecules can act as both promoters or inhibitors of stone formation depending on the chemical composition of urine in which they are operating. At the moment, there are no clinical applications of macromolecules in stone management or prophylaxis. Patients should be evaluated for the association with systemic pathologies.

PROPHYLAXIS

Personalized medicine and public health interventions are complementary to prevent stone recurrence. Personalized medicine addresses a small part of stone patients with a high risk of recurrence and systemic complications requiring specific dietary and pharmacological treatment to prevent stone recurrence and complications of associated systemic diseases. The more numerous subjects who form one or a few stones during their entire lifespan should be treated by modifications of diet and lifestyle. Primary prevention by public health interventions is advisable to reduce prevalence of stones in the general population. Renal stone formers at "high-risk" for recurrence need early diagnosis to start specific treatment. Stone analysis allows the identification of most "high-risk" patients forming non-calcium stones: infection stones (struvite), uric acid and urates, cystine and other rare stones (dihydroxyadenine, xanthine). Patients at "high-risk" forming calcium stones require a more difficult diagnosis by clinical and laboratory evaluation. Particularly, patients with cystinuria and primary hyperoxaluria should be actively searched.

FUTURE RESEARCH

Application of Artificial Intelligence are promising for automated identification of ureteral stones on CT imaging, prediction of stone composition and 24-hour urinary risk factors by demographics and clinical parameters, assessment of stone composition by evaluation of endoscopic images and prediction of outcomes of stone treatments. The synergy between urologists, nephrologists, and scientists in basic kidney stone research will enhance the depth and breadth of investigations, leading to a more comprehensive understanding of kidney stone formation.

Long-term results of extended Boari flap technique for management of complete ureteral avulsion: A case report

BACKGROUND

Ureteroscopy is well-established as a primary treatment modality for urolithiasis. Ureteral avulsion, particularly complete or full-length avulsion with a resultant long segment of the ureter left attached to the ureteroscope, is a rare but devastating complication of the procedure. Management of this complication is challenging. Moreover, general consensus regarding the optimal management is undetermined. We report our experience of managing a complete ureteral avulsion case via an extended Boari flap technique with long-term results.

CASE SUMMARY

A 41-year-old female patient subjected to complete ureteral avulsion caused by ureteroscopy was referred to our hospital. A modified, extended Boari flap technique was successfully performed to repair the full-length ureteral defect. Maximal mobilization of the bladder and affected kidney followed by psoas hitch and downward nephropexy maximized the probability of a tension-free anastomosis. Meticulous blood supply preservation to the flap also contributed to the success. During the 4-year study period, no complications except for a mild urinary frequency and a slightly lower maximum urinary flow rate were reported. The patient was satisfied with the surgical outcomes.

CONCLUSION

The extended Boari flap procedure is a feasible and preferred technique to manage complete ureteral avulsion, particularly in emergencies.

Inverted mucosa and avulsion ureteral injury in ureteroscopic procedure: A very rare complication of a common procedure in urology

An avulsion is very rare and the most serious complication that may occur during ureteroscopy in 0.06-0.45% of patients during the ureteral stone procedure. A sixty years-old female with a small stone in the upper third of the right ureter with high-grade hydronephrosis and underwent a ureteroscopy procedure. During withdrawal of the scope, the ureter was brought out in urethral meatus, with inverted fashion, nearly the whole length of the ureter was avulsed out. A nephrectomy of the right kidney was then performed. Knowledge about signs of the ureteral avulsion, pitfalls when to stop, and treatments is really important.

Ureteral Avulsion during Semirigid Ureteroscopy: A Single-Centre Experience

Aims

The aim of the study is to present our experience with the management of ureteral avulsions following semirigid ureteroscopy for ureteral stones. This is one of the largest series reported so far.

Methods and Materials

It is a retrospective and observational study done at Sri Ramachandra Institute of Higher Education and Research over the last 18 years.

Results

There were seven cases of ureteral avulsion following semirigid ureteroscopy. All patients were males with a mean age of 35.7 years. All had impacted stones, with proximal ureteric location in 6 patients and distal ureteric location in 1 patient. Five cases had two-point avulsions with loss of entire ureter. Two cases had one-point avulsion: one distal ureteric and the other mid-ureteric. Of the five cases with whole length ureteral avulsion, four were managed by classical ileal replacement of ureter and the the fifth case was managed by ileal replacement of ureter by the Yang–Monti technique. Of the two cases with one-point avulsion, one was managed by uretero-neocystostomy and the other by uretero-ureterostomy. All the patients had successful outcome.

Conclusions

Even though rare, ureteral avulsion can potentially happen especially when dealing with impacted ureteric stones. Being conscious of the possible occurrence of this serious complication during any difficult ureteroscopy and exercising utmost care during the procedure are important preventive measures. However, this catastrophe can be successfully managed by either immediate definitive repair or in a staged manner.

Immediate successful renal autotransplantation after proximal ureteral avulsion fallowing ureteroscopy: a case report

The patient was a 51-year-old lady with left flank colicky pain accompanied with nausea and vomiting for a month. Transurethral lithotripsy and ureteral stent placement was considered for the patient. The patient had a narrow ureteral lumen and while bringing the ureteroscope out, ureteral avulsion occurred at a distance approximately 4 cm from ureteropelvic junction. After bringing the uretroscope out, the avulsed ureter was observed hanging at the tip of the ureteroscope. Anastomosis of the ureter to the bladder was accomplished with Lich-Gregoir technique. A drainage tube was inserted at the site of incision and the surgical wound closed. The patient was discharged with acceptable general condition after 3 days and the drainage tube removed. The ureteral stent was removed 4 weeks later by cystoscopy. An ultrasound imaging study of the genitourinary system 8 months into the patients follow up showed normal size, echo and cortical thickness in the operated kidney after renal autotransplantation.