Endourologic procedures are very common in daily urologic practice for treatment of benign prostatic obstruction, stone disease, urothelial tumors, or stenosis.
To characterize the complications following endoscopic procedures, to describe their management, and to gather information about their prevention in current urologic practice.
A review of the literature was conducted using PubMed/Medline database to include the most relevant articles on the topic. The search focused on endoscopic approaches for treatment of prostate, bladder, or upper urinary tract disease. Percutaneous approaches and noninvasive extracorporeal techniques were excluded. Complications of endourologic procedures were identified through level 1 evidence, systematic reviews of the literature, or original articles assessing complications as the primary end point. Data about management and prevention of each type of complication were retrieved in a second round using specific keywords.
Complications of endoscopic urologic procedures are specific to each surgical approach. Main complications after prostate surgery include transurethral resection of the prostate syndrome, bleeding and transfusion, acute urinary retention, urinary tract infection, clot retention, postoperative irritative symptoms, ejaculatory dysfunction, urinary incontinence, bladder neck contracture, and urethral stricture. Major complications after transurethral bladder tumor include severe bleeding, transfusion, bladder perforation, and urinary tract infection. The most frequent complications after ureteroscopy are fever and sepsis, bleeding, steinstrasse, and ureteral injury. Overall, the literature is very poor, with no systematic reporting of complications and underuse of classification systems. No clear protocols are available for management of complications, and most are based on studies with low levels of evidence. Good clinical practice recommendations and guidelines give useful support about technical issues, intraoperative safety, and prevention of urinary tract infection. The efficacy of these preventive measures remains poorly investigated.
Complications following endoscopic surgery are potentially numerous and vary with patient characteristics, surgical approach, and type of medical device. Improved standardization and quality of publications are warranted to improve knowledge of these issues, which are directly linked to the level of care.
We focused on the potential complications of each endoscopic approach used to treat urologic disease. We described the frequency of these complications and gathered information about how to manage them in the operating theater. We also noted caveats for the literature regarding standardization of reporting and classification systems.
Keywords: Endoscopy, Complications, Prostate, Bladder resection, Ureteroscopy.
Endoscopic procedures are widely used to treat a variety of urologic diseases. Endoscopy is usually considered a minimally invasive surgical approach because it allows surgical treatment without parietal incision, thus avoiding specific complications of surgical wounds and reducing postoperative pain. Endoscopic procedures have evolved rapidly in recent years thanks to a number of technical innovations  and are considered first-line options for the treatment of benign prostatic obstruction (BPO), stone disease, and non–muscle-invasive urothelial tumors , , and .
Although these approaches have been associated with favorable results and high efficacy, they are associated with specific complications that need to be properly assessed, managed, and prevented. This paper gathers the experience described in the literature regarding complications of all endoscopy procedures currently used in clinical practice.
2. Evidence acquisition
A literature search was conducted in September 2015 within the PubMed/Medline database to gather available information on all types and respective occurrences of complications following endoscopic procedures related to BPO relief, ureteroscopic management of stone disease, and transurethral resection (TUR) of the bladder. The search was conducted in two steps. First, all complications were listed based on level 1 evidence from the literature, including any systematic review or study specifically focused on complications of the above-mentioned procedures. This search used the keywords prostate OR ureteroscopy OR bladder tumor resection associated with the keywords complications AND randomized OR systematic review. A pooled analysis was done to approach the overall frequency of each complication. In a second round, a specific focus was placed on each complication with an additional search using the complication type and the procedure as a research term. The relevance of each paper retrieved was evaluated by all authors. Selection of the papers was based on the authors’ expertise. Only articles published after 1995 as full-text publications in the English or French language were considered. The present paper should not be considered a proper systematic review of complication epidemiology or classification but rather as a narrative review summarizing the data about management and prevention of each complication.
Because they are not strictly endoscopic procedures, nonablative techniques for BPO management, percutaneous surgery, extracorporeal shockwave lithotripsy, and laparoscopic or robotic approaches were considered to be beyond the scope of this review. Complications caused by preexisting conditions, related to anesthesia, or not directly related to surgery were also excluded.
3. Evidence synthesis
Reporting of complications following endoscopic procedures is far from optimal in the available studies, with a lack of standardization and overall low quality. As recently stated by the European Association of Urology (EAU) guidelines committee, there is an urgent need for more systematic, high-quality reporting of surgical procedures , and that is clearly lacking in the field. Furthermore, the main classification systems used in current clinical research do not necessarily fit the requirements for proper reporting of complications after surgical procedures , , and .
Another issue regarding surgical complications is the impact of the learning curve . Each specific intervention requires specific training, and lack of experience can partly explain technical failures or complications. Although beyond the scope of the current review, the authors emphasize the need for proper training as well as respect for the rules of good clinical practice to optimize complication rates.
3.1. Prostate surgery
Several systematic reviews and meta-analyses have been published that gathered the level 1 evidence available regarding endoscopic approaches to BPO relief , , , , and . Large cohort studies and reports specifically focused on complications were also included to detect less frequent complications.
Enough material was retrieved to describe the occurrence of each complication for various endoscopic surgical approaches, namely, monopolar TUR of the prostate (M-TURP), bipolar techniques (bipolar plasma vaporization of the prostate, bipolar plasma enucleation of the prostate [similar to plasmakinetic enucleation of the prostate]), bipolar TUR of the prostate (B-TURP), GreenLight (American Medical Systems, Minnetonka, MN, USA) photoselective vaporization of the prostate (PVP), holmium laser enucleation of the prostate (HoLEP), thulium enucleation of the prostate, and thulium vaporesection (ThuVARP) procedures. Given the number of procedures described (variants of enucleation, vaporization, resection, and combined techniques) and the growing number of devices tested (eg, different bipolar devices, successive generations of GreenLight laser), the rate of complications per technique could only be evaluated roughly. For some new emerging devices (eg, diode lasers), reliable data are sparse or do not exist to assess complication rates.
The respective occurrences of the most frequent specific complications for techniques currently used in clinical practice (level 1 validated), based on the current literature, are listed in Table 1 (perioperative complications) and Table 2 (late complications). In addition, several other complications have been described as possible but rare or exceptional. Those complications include large capsular perforation , rectal perforation , injury of ureteral orifices , severe urethral injury  and , intraperitoneal bladder rupture or explosion  and , migration of a device within the retroperitoneum , urethroperineal fistula , prostatosymphyseal fistula  and , incrusting cystitis, chronic pelvic pain, pubic osteomyelitis , vascular air embolism , acute abdominal compartment syndrome, and bone dissemination of prostate cancer after HoLEP . Mortality of transurethral procedures for BPO relief has been estimated at approximately 3 in 1000 patients in large M-TURP series  and are mainly due to massive perioperative bleeding, decompensation of a severe preexisting organ failure, or a complication of anesthesia.
|Acute urinary retention||3–9||0–6||1.3–7.7||1–5||3–16|
|Urinary tract infection||4–20||3–6||2–6||0–10||2–50|
|Dysuria/storage LUTS *||15||10||11||14||10|
* Definition of storage LUTS and dysuria was highly heterogeneous among trials. Pooled values of meta-analysis are presented but should be taken with caution.
BPVP = bipolar plasma vaporization of the prostate; B-TURP = bipolar resection of the prostate; HoLEP = holmium laser enucleation of the prostate; LUTS = lower urinary tract symptoms; M-TURP = monopolar transurethral resection of the prostate; PVP = photovaporization of the prostate; TURP = transurethral resection of the prostate.
Based on updated data from Cornu et al. . Data are shown in percentages.
|Urethral/bladder neck strictures||2–10||1–6||1.4–4||5–9||0–3|
BPVP = bipolar plasma vaporization of the prostate; B-TURP = bipolar resection of the prostate; HoLEP = holmium laser enucleation of the prostate; M-TURP = monopolar transurethral resection of the prostate; PVP = photovaporization of the prostate.
Data are shown in percentages.
It is noteworthy that in nearly all randomized controlled trials (RCTs), complications are not the primary outcome of the study and are simply described without any rigorous standardization. Furthermore, some complications were not adequately defined (eg, prostatic capsule perforation, ejaculatory dysfunction, urethral strictures, and postoperative storage symptoms). Data regarding the prevention and management of the most frequent complications of currently validated techniques are detailed in the following sections. Main complications by technique are presented in Figure 1 and Table 1 and Table 2.
3.1.1. Technical issues, surgical intervention, and points of technique
To begin, the use of a properly validated device must be considered. Although many new medical devices are launched on the market for BPO surgery, and given that the CE (Conformité Européene) mark is the only requirement for introduction in clinical practice in many European countries, it has to be stated that only validated devices with level 1 evidence can be used with dependable safety outside a research protocol .
Patient preparation and installation are similar regardless of the technique used (dorsal lithotomy position). Initially, the urethra and the bladder are explored comprehensively, and the locations of key anatomic structures (ureteral orifices, verumontanum, and urinary sphincter) and the shape of the prostatic lobes are determined. A two-way endoscope is usually used for continuous flow irrigation. Glycine or solutions of sorbite (ie, sorbitol) or mannite (ie, mannitol) are used for irrigation during M-TURP, whereas saline is used in endoscopic bipolar surgery. The surgery is usually conducted according to the initial description. Detailing every surgical technique goes beyond the scope of this review, but it must be mentioned that a basic description of each technique has been properly published and occasionally further modified by other experts , , , , , , and . The use of a well-standardized technique is recommended unless used within clinical research protocols. Regardless of the technique used, the two most common complications during intervention are bleeding and capsular perforation.
Bleeding is a common phenomenon that can happen regardless of the technique used. Because bleeding can obscure vision, it has to be managed rapidly, with proper focal contact coagulation when using electric energy . For laser applications, coagulation is performed according to the physical characteristic of the wavelength. For holmium lasers, defocusing of the beam (ie, activating laser energy at an appropriate distance) translates to coagulation; for thulium:yttrium–aluminum–garnet lasers, either defocusing or lowering the energy to 20–30 W leads to coagulation rather than vaporization; for lithium borate (LBO) or potassium titanyl phosphate (KTP) lasers (ie, PVP), lowering the energy is the choice. The distance to the tissue is not relevant because the laser energy of LBO and KTP is not absorbed in water, as hemoglobin is the chromophore , , and . A switch to monopolar energy can be used with a large electrode (eg, roller ball electrode). In case of B-TURP, a button or vaporization probe can facilitate firmer hemostasis. In case of massive bleeding, the procedure can be resumed with placement of a transurethral irrigation (Foley) urethral catheter. Reasonable traction can be applied. In addition to medical support (eg, transfusion), some authors have described success with prostatic embolization in cases necessitating immediate or delayed salvage procedures  and . Although there is no technical recommendation to avoid bleeding, two important aspects must be considered: (1) The use of laser devices has shown a clear advantage over M-TURP regarding perioperative blood loss , and (2) some patients are particularly at risk of bleeding because of coagulopathy, anticoagulation therapy, or anti–platelet aggregation therapy. It is recommended that patients at risk of bleeding receive laser therapy ; however, it should be emphasized that no valuable level 1 evidence has been provided for this category of patients . Furthermore, no consensus exists about the use of anticoagulation medications in a perioperative setting (eg, whether to stop, replace, or continue) .
Capsular perforation is another common concern during transurethral procedures for BPO relief . From a technical point of view, capsular perforations can be generated by deep resection or vaporization or by losing the correct plane during enucleation. Different types of capsular perforations have been described: (1) simple vision of periprostatic fat through periprostatic fibers, (2) visible periprostatic fat, (3) free hole admitting irrigation without periprostatic fat visible, and (4) complete perforation with bladder neck false passage . The latter is usually designated as undermining of the bladder neck and can lead to serious complications. The consequences of capsular perforation can be fluid extravasation and absorption, bleeding, or even injury of adjacent organs. Although benign and focal capsular perforations are usually compatible with the completion of the procedure, a major extravasation of irrigation fluid can lead to putting a urinary catheter properly in place and resuming the procedure. Although a “TUR syndrome” does not exist in saline irrigation, the fluid absorption must be estimated, especially in patients with cardiovascular morbidities, while continuing the surgery with major capsular perforations . Perforation can be shown by carefully identifying the limits of the resection or the enucleation plane, especially at the junction of the prostatic capsule and the bladder neck.
Morcellation is specific to the enucleation technique and can lead to bladder injury. This complication has been reported in nearly all large enucleation series and is due to contact between the morcellator tip and the vesical mucosa . In general, it must be kept in mind that morcellation has its own learning curve of about 20 procedures within the learning curve of transurethral enucleation .
Morcellators available on the market have different properties regarding suction, rapidity, shape, and vision , , and , and no firm recommendation can be made about the superiority of one morcellator over another. Basic recommendations for safe morcellation are good vision (ie, good hemostasis), good (double) irrigation with an inflated bladder, and continuous control of the tip of the device . There is no standard recommendation regarding the “upward” (conventional) and “downward” (alternative) techniques, the latter having been described recently as making the procedure safer .
3.1.2. Transurethral resection syndrome
TUR or TUR of the prostate (TURP) syndrome results from absorption of hypotonic solution (glycine or sorbitol/mannitol) into the prostatic venous sinuses that results in an impaired electrolyte balance and hyponatremia and fluid overload (ie, hypotonic hyperhydration)  and . Its frequency after M-TURP is estimated as approximately 1%. When symptomatic, hyponatremia can result in nausea, confusion, and blurred vision, and in rare cases, the condition is life threatening because of cerebral edema and fluid overload. Appropriate management of TURP syndrome includes interruption of the procedure, cardiopulmonary support, and adequate normalization of hyponatremia. TURP syndrome can be prevented by limiting the duration of M-TURP procedures and, indirectly, by selecting patients with prostate volume <80 ml.
TURP syndrome in itself cannot occur during endoscopic procedures with isotonic saline irrigation; however, it has been shown that absorption of fluid irrigation is common, even during laser procedures, and can result in significant fluid overload  and . Risk factors for fluid absorption include irrigation volume and extensive ablation near the prostatic capsule.
TUR syndrome does not exist in bipolar surgery of the prostate using saline irrigation, but volume uptake must be kept in mind .
3.1.3. Postoperative bleeding
Postoperative bleeding is considered an early postoperative complication of surgery when occurring within 1 mo after surgery. There is a correlation with prostate size  and . Immediate postoperative bleeding is usually prevented or treated by bladder irrigation and clot removal if necessary (manual extraction). In patients under anticoagulation or anti–platelet aggregation therapy, suspension of the treatment can be proposed but must be balanced with the risk of decompensation of associated conditions (especially cardiovascular). In the most severe cases, as stated above, surgical revision with endoscopic clot removal and targeted coagulation or even salvage embolization of the prostate can be proposed.
HoLEP and GreenLight PVP, ThuVARP, and bipolar resection and enucleation have shown clear reduction of early postoperative bleeding complications compared with M-TURP in a recent meta-analysis  and . However, a recent study that focused on postoperative clot retention found that M-TURP and B-TURP led to comparable rates of postoperative urinary retention .
Delayed postoperative bleeding is less accurately evaluated in RCTs. Some cohort studies have recently pointed out the high frequency of gross hematuria several weeks after PVP . Oral anticoagulation has been noted as a favorable factor. Oral anticoagulation has also been mentioned as potentially responsible for gross hematuria after HoLEP . There is no clear preventive measure to avoid delayed hematuria, and, as stated above, the ideal management of anticoagulation therapy before, during, or after BPO surgery remains unknown.
3.1.4. Postoperative retention
Postoperative urinary retention after BPO relief surgery has been described after all surgical approaches . Recatheterization is usually required and can diagnose clot retention. When no bleeding is seen, potential causes are persistent obstruction, residual chips of prostatic tissue obstructing the urethra, or underactive bladder. Usually a subsequent trial of voiding without a catheter is scheduled rapidly after recatheterization, and if it fails, the patient must be reevaluated by endoscopy and urodynamics, if necessary . Several hypotheses have attempted to explain prolonged failure to void after BPO surgery (eg, indwelling catheter before surgery, prolonged obstruction), but data for predictive factors are sparse. A very likely explanation could be the phenomenon of detrusor underactivity, which has finally gained attention . Another limitation is the lack of clear and systematic reporting of postoperative retention events; in most studies, clot retention, transient urinary retention, prolonged bladder drainage, and reintervention for persistent obstruction are not differentiated.
3.1.5. Postoperative storage symptoms and dysuria
Postoperative storage symptoms and pain while voiding are common features after endoscopic surgery for BPO but remain poorly evaluated and incompletely understood  and . Reporting of those symptoms is very heterogeneous without an adequate questionnaire. Indeed, the International Prostate Symptom Score is not validated in this situation, as it requires symptoms to be stable over 3 wk. Some authors have investigated pain while voiding  in an RCT comparing M-TURP and PVP 120 W and found no significant difference using a nonvalidated questionnaire. A more systematic evaluation of postoperative symptoms is warranted.
Similarly, no formal consensus has been reached concerning treatment of transient irritative symptoms after BPO surgery. Antimuscarinics, α-blockers, and nonsteroidal anti-inflammatory agents have been proposed, but no comparative study is available in this field. No obvious predictive factor has been established.
3.1.6. Urinary tract infections
Urinary tract infections (UTIs) are common after BPO surgery; however, there is no standardization for reporting of this complication, which is always considered a secondary outcome in RCTs. No details about symptoms, urine culture criteria, or treatment are available in these studies. Given the lack of evidence, postoperative UTIs should be treated according to the current clinical guidelines . Similarly, their prevention is based on preoperative administration of antibiotics considering the preoperative urine culture results, according to current clinical guidelines. Preoperative positive urine culture is usually treated with oral or intravenous antibiotics at least 48 h before surgery, and no control culture is done. The case of a patient under Clean Intermittent Self Catheterization (CISC) is less crucial because it is rare to do surgery on such patients; however, the same recommendations can be made.
Urge urinary incontinence after BPO surgery can be related to early postoperative irritative symptoms, as described above. When overactive bladder or bladder dysfunction is present before obstruction relief, it may persist after surgery in approximately 50% of cases. Predictive factors for persistent bladder dysfunction after BPO relief are not completely clear, but preoperative detrusor overactivity on urodynamics has been found to be associated with worse outcomes. Subsequent management of urge urinary incontinence is based on antimuscarinics or second-line therapies (eg, botulinum toxin intradetrusor injections, posterior tibial nerve stimulation, sacral neuromodulation) after a complete work-up including urodynamics . Mirabegron has not yet been investigated in this situation. Stress urinary incontinence (SUI) can occur after BPO surgery and is mostly transient. After resection or vaporization, SUI is rather uncommon (Table 1); when persistent during follow-up, it is usually related to injury of the external urinary sphincter. After enucleation, transient SUI has been described in up to 20% of cases, with most cases resolving within 1 yr. Predictive factors for urinary incontinence after HoLEP include learning curve  and technical issues (some modifications of the initial technique have been proposed ). Too few data are available to date to make a statement about alternative enucleation methods (thulium, diode, bipolar or GreenLight enucleation), but similar results can be anticipated.
The first treatment for management of postoperative SUI is pelvic floor muscle exercises (Kegel exercises), especially in the early postoperative period. If SUI symptoms persist after 1 yr, a surgical treatment can be proposed after a complete evaluation, as recommended . Currently available options are male slings, artificial urinary sphincter implantation, periurethral balloons, or bulking agents.
3.1.8. Bladder neck and urethral structures
Bladder neck and postoperative urethral strictures are long-term complications that have been reported after all currently used techniques for BPO relief in up to 10% of cases (Table 1). However, their frequency can only be estimated because both complications are often confounded in published reports . Urethral strictures are commonly considered consequences of stretching of the urethra by the resectoscope ; however, urethral injury can be a consequence of the electrical current within the external sheath of the endoscope  and . The treatment of these strictures can be done by dilatation or incision or by urethroplasty for complex cases.
Bladder neck contracture is seen in <10% of cases and is thought to result from ischemia and scar formation in the bladder neck after BPO relief procedures; cardiovascular risk factors seem to be implicated . Treatment of bladder neck contracture is based on endoscopic surgery by incision.
3.1.9. Sexual dysfunction
Sexual dysfunction after BPO relief is a complex, multifactorial topic that has been explored extensively in the literature but with several limitations  and . A limited number of studies with high levels of evidence show that currently used techniques have a limited impact on erectile function . In contrast, ejaculatory dysfunction has been clearly established, with >70% anejaculation after HoLEP, approximately 60% after TURP, and 35% after GreenLight PVP . These figures seem to be linked to the amount of prostatic tissue removed during the intervention, and that is greater with enucleation techniques.
Although ejaculatory dysfunction has long been considered a logical secondary effect of BPO surgery, some recent advances have been made toward a potential tradeoff between BPO relief and preservation of sexual function. Modified techniques of TURP and GreenLight PVP have been proposed as “ejaculation-sparing techniques” with promising results that compete with nonablative approaches, which have been shown to lower the risk of postoperative ejaculatory dysfunction  and . Long-term results, especially regarding efficacy of BPO relief, are awaited.
3.2. Bladder endoscopic surgery
The most common immediate complications after TUR for bladder tumor include perioperative severe bleeding (2–13%), transfusion (3–7%), bladder perforation (2.5–5% or less, intraperitoneal or extraperitoneal), and urinary tract infection (3%) , , and  (Fig. 2). Less frequent complications include injury and stenosis of the ureteral orifices or secondary urethral stenosis. Other exceptional complications such as postoperative fistula, bladder explosion, reabsorption syndrome, and false passage can also occur  and .
3.2.1. Bladder perforation
Bladder perforation can be the consequence of too deep a resection or an obturator nerve reflex. If bladder perforation is seen, it must be assessed to determine whether it is intraperitoneal or extraperitoneal (90% of cases). Cystography can be done in case of doubt. Some authors  argue that extravesical perforation is difficult to assess because mandatory resection of the muscle at the diagnosis phase may lead to visualization of perivesical fat. In the vast majority of cases, placement of an indwelling catheter and prolonged drainage can lead to bladder healing. In case of intra-abdominal perforation with massive extravasation of irrigation fluid or bleeding, the closure of the bladder by the abdominal approach (laparoscopic or open) is recommended. Significant bladder perforation has several implications including contraindication for immediate postoperative intravesical therapy  and theoretical risk of extravesical tumor seeding. The latter has been described in contemporary series , whereas other authors found that adequate management of bladder perforation was not associated with worse outcomes . Bladder perforation can be prevented by rigorous and careful surgical technique, the use of isotonic fluid, and avoidance of overdistension, especially at the dome or in the region of the obturator nerve. Alternative techniques have been presented to reduce the rate of bladder perforation (bipolar and laser techniques).
Significant intraoperative or immediate postoperative bleeding occurs in 2–13% of patients in the literature and is favored by anticoagulation therapy and specific tumor characteristics (eg, large size, muscle invasion) . Transfusion in used in 3–7% of cases in the literature, usually in the operating room or immediately after . Perioperative management of bleeding includes clot removal by catheter, proper irrigation, and reintervention if necessary. Because no specific prevention of bleeding can be done, some authors have introduced the use of laser devices.
3.2.3. Urinary tract infection
Urinary tract infection is not uncommon and is probably underreported in the literature. Endoscopic management of bladder tumor is not associated with a specific risk of UTI, and the actual rules of prevention specified in the EAU guidelines should be respected .
3.2.4. Alternatives to monopolar transurethral resection
Bipolar TUR has been proposed to replace monopolar TUR to improve safety (by lowering bleeding complications, obturator nerve reflex, and bladder perforation) and quality of the retrieved specimens. However, the results of currently available trials cannot firmly establish the superiority of this approach, as stated by the current EAU guidelines .
Laser resection has been evaluated through recent systematic reviews and meta-analyses  and . Although a small number of heterogeneous studies were gathered, results were in favor of reduced irrigation time, reduced catheterization time, and shorter hospital stay. The rate of bladder perforation was also reduced, as was the obturator nerve reflex during the procedure. As stated by Kramer et al. , however, the report of complications after laser TUR was not rigorous in the studies published to date, without any systematic description or classification. The role of laser resection must be further confirmed in long-term, well-designed studies; the technique is not yet considered as the gold standard but rather as an option for frail patients .
En bloc resection of bladder tumors (ERBT) has been proposed as an alternative to traditional TUR. It has been shown to be feasible using various sources of energy, including monopolar and bipolar devices as well as thulium and holmium laser . The rate of reintervention for immediate complications is reported to be approximately 2.7%, which is similar to series of TUR . Comparative studies seemed to favor the use of laser devices . The existing literature to date does not allow any recommendation yet with regard to ERBT, but early results are promising.
Retrograde ureteroscopy is widely used for stone disease management, minimally invasive treatment of upper tract urothelial carcinoma, and ureteral stenosis  and . Recent technological advances (miniaturization, improved mechanism, enhanced optical quality, disposable devices) have expanded the indications for ureteroscopy  and . The most frequent complications of ureteroscopy are fever (2–28%), sepsis (3–5%), bleeding (5%), steinstrasse (1%), and ureteral injury  (Fig. 3). Intraoperative failure can occur because of technical problems or intraoperative complications. Rare complications (<1%) include severe ureteral damage and avulsion, ureteral strictures, kidney damage, severe bleeding with transfusion, and fistulas . Mortality of the procedure is very low, with only a few cases reported to date .
3.3.1. Technical issues
Ureteral stones and tumors can be managed by rigid ureteroscopy or flexible ureteroscopy, whereas renal stones are treated only with flexible devices . The EAU recently published what constitutes the best clinical practice in endourology to avoid technical failure and complications during retrograde ureteroscopy .
The procedure is conducted under general anesthesia in most cases. The use of a safety guide wire is recommended, and fluoroscopic equipment must be available in the operating room . Ureteral access can be facilitated with dilatation of the ureteral orifice by plastic or balloon dilatators or by placing a rigid scope prior to a flexible endoscope. In case of technical difficulties, placement of a ureteral stent and rescheduling of retrograde endoscopy 1–2 wk later is also a safe and valuable alternative. In case of significant ureteral injury, bleeding, false passage, or any severe intraoperative complication, placement of a ureteral stent can be recommended and should be possible on the safety guide wire.
Ureteral access and retrograde ureteroscopy procedures can be facilitated by the use of a ureteral access sheath . The potential benefits of a ureteral access sheath include easier access to the kidney, improved vision, protection of the scope, and reduction of intrarenal pressure ; however, placement of a disposable hydrophilic coated ureteral sheath is not recommended in all cases and can lead to ureteral injuries  and . This risk seems lower in prestented ureters. No firm data are available in terms of long-term effects of potential ureteral damage due to access sheath use. Several types of sheaths are now available on the market. The size of the sheath should be chosen in relation to the size of the scope . The optimal length depends on the size and the sex of the patient to avoid having too much of the sheath outside.
Various types of ureteroscopes can be used, and the type of instrument does not seem to influence complication outcomes. The use of holmium laser for stone fragmentation has been shown to be safe and can be recommended for both rigid and flexible ureteroscopy procedures. Irrigation is led via an active pumping system that allows flushing of saline into the kidney regularly. Usual settings are 51–71 cm H2O.
The optimal duration of the procedure remains unknown. Because the upper tract is under pressure throughout the procedure, theoretically, there is a risk of renal fornix rupture and diffusion of irrigation fluid during intervention. In case of very large or numerous stones, resuming the procedure with placement of a ureteral stent and scheduling an additional procedure seem reasonable. The use of an access sheath, however, seems to reduce this risk by influencing the procedure .
Stone extraction should be done by forceps or nitinol baskets during rigid ureteroscopy procedures. Only flexible nitinol baskets can be used during flexible ureteroscopy. The extraction tool must be kept under visual control at all times, and the size of the fragments must be compatible with smooth extraction without injury to the bladder wall. If the fragment is blocked in the ureter, additional fragmentation is warranted to proceed with safe extraction. When stones are entrapped in the basket, one should never try to pull on the basket, possibly injuring the ureter. The basket can be opened, and the use of pressure flow can free the stone. If the stone is impacted or cannot move, a possible option is to cut the basket, leave it in place, and come back with a laser fiber to incise the arms of the basket.
Placement of a stent after ureteroscopy is not mandatory in all cases. EAU guidelines recommend stent placement in complex cases, ureteral trauma, residual fragments, bleeding, perforation, infection, or pregnancy. Some authors recommend the use of a ureteric catheter for 1 d in other cases .
3.3.2. Urinary tract infections
In case of proven UTI before intervention, several days of treatment are mandatory . In case of sterile urine culture preoperatively, the usual rules for prevention of infections should be respected .
Despite this, up to 20% of patients present postoperative UTIs . Proposed predictive factors for symptomatic postoperative UTI include preoperative infections, preoperative stenting, and longer operative time . The impact of prestenting can be explained by bacterial adherence to the stent. In the context of struvite stones, it could be useful to use antibiotics targeting the germs found in stone or urine culture from the renal pelvis, as midstream urine culture may not reflect the causative microorganism .
Minor bleeding is a common intraoperative complication, mostly due to minor trauma of the ureteral orifice or the mucosa during surgery, that could be adequately managed by continuous irrigation flow during the procedure . When bleeding obscures vision and does not stop spontaneously, the procedure can be resumed with placement of a ureteral catheter. According to the literature, significant bleeding occurs in ≤1%. Massive bleeding can be caused by a fistula between a vessel and the ureter, requiring radiologic diagnosis and subsequent embolization.
3.3.4. Ureteral injury
Ureteral injury or perforation is the most frequent serious intraoperative complication during ureteroscopy and depends on the stone location. Ureteral stones, especially midureter stones, pose particular risk. The use of small ureteroscopes and compliance with good clinical practice guidelines can reduce the potential rate of ureteral perforation .
Ureteral avulsion is a rare but serious complication that occurs in <0.5% of the procedures . The lumbar part of the ureter is most at risk because it is weaker. The use of a rigid cystoscope is associated with higher risk. Most of the time, the impacted stone is held by the basket. Management of ureteral avulsion depends on many parameters including age, preoperative condition, kidney function, contralateral kidney, patient preference, and surgeon experience. Acute management can be done by percutaneous drainage, especially if the condition was initially misdiagnosed. Definitive treatment options include nephrectomy, end-to end anastomosis for lumbar injuries, reimplantation for distal injuries, and psoas bladder and Boari flap for iliac ureter injury. Reconstructive urology options such as ileoplasty or autotransplantation are also possible .
Complications following endoscopic surgery are potentially numerous and vary with patient characteristics, surgical approach, medical device, and surgeon experience. The actual rate remains difficult to estimate because of the lack of standardization and the low quality of currently available reports. Each type of complication can be at least partly prevented by following the rules for good clinical practice.
Given the impact on patient care and the importance of assessment of new technologies, improved reporting and better standardized management of complications with the endoscopic approach would be highly beneficial.
Author contributions: Jean Nicolas Cornu had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: CORNU, MATLAGA.
Acquisition of data: CORNU, HERMANN.
Analysis and interpretation of data: CORNU, HERMANN, TRAXER, MATLAGA.
Drafting of the manuscript: CORNU.
Critical revision of the manuscript for important intellectual content: CORNU.
Statistical analysis: CORNU.
Obtaining funding: None.
Administrative, technical, or material support: None.
Supervision: MATLAGA, TRAXER.
Financial disclosures: Jean Nicolas Cornu certifies that all conflicts of interest, including specific financial interests and relationships and affiliations relevant to the subject matter or materials discussed in the manuscript (eg, employment/affiliation, grants or funding, consultancies, honoraria, stock ownership or options, expert testimony, royalties, or patents filed, received, or pending), are the following: Jean-Nicolas Cornu has received honoraria/travel grants/consultancies from Astellas, Pfizer, Coloplast, AMS, Mundipharma, Bard, GSK, BK Medical, Allergan, and EDAP-TMS. Thomas R. W. Herrmann is affiliated with Karl Storz GmBH (honoraria, financial support for attending symposia, financial support for educational programs, consultancy, advisory, royalties), Boston Scientific AG (honoraria, financial support for attending symposia, financial support for educational programs, consultancy, advisory board), LISA Laser OHG AG (honoraria, financial support for attending symposia, financial support for educational programs), and Ipsen Pharma (honoraria, financial support for attending symposia, advisory board). Olivier Traxer is a consultant for Coloplast, Boston Scientific, Rocamed, Olympus, and EMS. Brian Matlaga is a consultant for Boston Scientific.
Funding/Support and role of the sponsor: None.
-  T.R. Herrmann, E.N. Liatsikos, U. Nagele, O. Traxer, A.S. Merseburger. EAU Guidelines Panel on Lasers, Technologies. EAU guidelines on laser technologies. Eur Urol. 2012;61:783-795
-  M. Oelke, A. Bachmann, A. Descazeaud, et al. EAU guidelines on the treatment and follow-up of non-neurogenic male lower urinary tract symptoms including benign prostatic obstruction. Eur Urol. 2013;64:118-140
-  M. Babjuk, M. Burger, R. Zigeuner, et al. EAU guidelines on non-muscle-invasive urothelial carcinoma of the bladder: update 2013. Eur Urol. 2013;64:639-653
-  C. Türk, A. Petřík, K. Sarica, et al. EAU guidelines on interventional treatment for urolithiasis. Eur Urol. 2016;69:475-482
-  D. Mitropoulos, W. Artibani, M. Graefen, et al. Reporting and grading of complications after urologic surgical procedures: an ad hoc EAU guidelines panel assessment and recommendations. Eur Urol. 2012;61:341-349
-  C. Mamoulakis, I. Efthimiou, S. Kazoulis, I. Christoulakis, F. Sofras. The modified Clavien classification system: a standardized platform for reporting complications in transurethral resection of the prostate. World J Urol. 2011;29:205-210
-  O. Kwon, S. Park, M.Y. Jeong, S.Y. Cho, H. Son. Application of the modified Clavien classification system to 120W Greenlight high-performance system photoselective vaporization of the prostate for benign prostatic hyperplasia: is it useful for less-invasive procedures?. Korean J Urol. 2013;54:239-243
-  B. Peyronnet, B. Pradere, N. Brichart, et al. Complications associated with photoselective vaporization of the prostate: categorization by a panel of GreenLight users according to Clavien score and report of a single-center experience. Urology. 2014;84:657-664
-  H.N. Shah, A.P. Mahajan, S.S. Hegde, M.B. Bansal. Peri-operative complications of holmium laser enucleation of the prostate: experience in the first 280 patients, and a review of literature. BJU Int. 2007;100:94-101
-  J.N. Cornu, S. Ahyai, A. Bachmann, et al. A systematic review and meta-analysis of functional outcomes and complications following transurethral procedures for lower urinary tract symptoms resulting from benign prostatic obstruction: an update. Eur Urol. 2015;67:1066-1096
-  R.D. da Silva, L. Bidikov, W. Michaels, D. Gustafson, W.R. Molina, F.J. Kim. Bipolar energy in the treatment of benign prostatic hyperplasia: a current systematic review of the literature. Can J Urol. 2015;22:30-44
-  I. Kyriazis, P.P. Świniarski, S. Jutzi, et al. Transurethral anatomical enucleation of the prostate with Tm:YAG support (ThuLEP): review of the literature on a novel surgical approach in the management of benign prostatic enlargement. World J Urol. 2015;33:525-530
-  Y. Zhu, J. Zhuo, D. Xu, S. Xia, T.R. Herrmann. Thulium laser versus standard transurethral resection of the prostate for benign prostatic obstruction: a systematic review and meta-analysis. World J Urol. 2015;33:509-515
-  Lin Y, Wu X, Xu A, et al. Transurethral enucleation of the prostate versus transvesical open prostatectomy for large benign prostatic hyperplasia: a systematic review and meta-analysis of randomized controlled trials. World J Urol. In press.
-  C. Brunken, C. Seitz, H.H. Woo. A systematic review of experience of 180-W XPS GreenLight laser vaporisation of the prostate in 1640 men. BJU Int. 2015;116:531-537
-  T. Fardoun, R. Mathieu, S. Vincendeau, et al. Risk of rectal perforation during intention to treat laser photovaporization of prostate with transrectal ultrasound guidance: a report of 4 cases. Prog Urol. 2015;25:101-106
-  V. Misraï, N. Barry Delongchamps, S. Lebdai, et al. Serious and unexpected complications of benign prostatic obstruction surgery: results of the LUTS committee survey from urologists of the French Urological Association. Prog Urol. 2015;25:583-589
-  G. Robert, A. Descazeaud, N.B. Delongchamps, et al. Transurethral plasma vaporization of the prostate: 3-month functional outcome and complications. BJU Int. 2012;110:555-560
-  K.T. Adiyat, A. Shetty, T. Jayakrishnan. Laparoscopic repair of a rare case of bladder rupture due to intravesical explosion during transurethral resection of the prostate. Urol J. 2014;11:1692-1694
-  A. Sanchez, D. Rodríguez, J.S. Cheng, F.J. McGovern, S. Tabatabaei. Prostato-symphyseal fistula after photoselective vaporization of the prostate: case series and literature review of a rare complication. Urology. 2015;85:172-177
-  D.M. Kaplon, H. Iannotti. Prostatic capsular perforation with extravasation resulting in pubic osteomyelitis: a rare complication of KTP laser prostatectomy. J Endourol. 2008;22:2705-2706
-  T. Kato, M. Sugimoto, Y. Matsuoka, et al. Case of vascular air embolism during holmium laser enucleation of the prostate. Int J Urol. 2015;22:227-229
-  D. Koguchi, M. Nishi, T. Satoh, et al. Bone dissemination of prostate cancer after holmium laser enucleation of the prostate: a case report and a review of the literature. Int J Urol. 2014;21:215-217
-  O. Reich, C. Gratzke, A. Bachmann, et al. Morbidity, mortality and early outcome of transurethral resection of the prostate: a prospective multicenter evaluation of 10,654 patients. J Urol. 2008;180:246-249
-  M.R. Fraundorfer, P.J. Gilling. Holmium: YAG laser enucleation of the prostate combined with mechanical morcellation: preliminary results. Eur Urol. 1998;33:69-72
-  J. Rassweiler, D. Teber, R. Kuntz, R. Hofmann. Complications of transurethral resection of the prostate (TURP)--incidence, management, and prevention. Eur Urol. 2006;50:969-979
-  C. Tholomier, R. Valdivieso, P.A. Hueber, K.C. Zorn. Photoselective laser ablation of the prostate: a review of the current 2015 tissue ablation options. Can J Urol. 2015;22:45-52
-  T. Bach, C. Netsch, L. Pohlmann, T.R. Herrmann, A.J. Gross. Thulium: YAG vapoenucleation in large volume prostates. J Urol. 2011;186:2323-2327
-  K.C. Zorn, D. Liberman. GreenLight 180W XPS photovaporization of the prostate: how I do it. Can J Urol. 2011;18:5918-5926
-  F. Gomez Sancha, V.C. Rivera, G. Georgiev, A. Botsevski, J. Kotsev, T. Herrmann. Common trend: move to enucleation-is there a case for GreenLight enucleation? Development and description of the technique. World J Urol. 2015;33:539-547
-  A. Barbieri, M. Simonazzi, C. Marcato, et al. Massive hematuria after transurethral resection of the prostate: management by intra-arterial embolization. Urol Int. 2002;69:318-320
-  A. Delgal, J.P. Cercueil, N. Koutlidis, et al. Outcome of transcatheter arterial embolization for bladder and prostate hemorrhage. J Urol. 2010;183:1947-1953
-  A. Descazeaud, R. Mathieu. Oral anticoagulation therapy and laser surgery for benign prostatic hyperplasia: stop, replace, or continue?. Curr Opin Urol. 2016;26:35-41
-  M.S. Choo, H.E. Lee, J. Bae, S.Y. Cho, S.J. Oh. Transurethral surgical anatomy of the arterial bleeder in the enucleated capsular plane of enlarged prostates during holmium laser enucleation of the prostate. Int Neurourol J. 2014;18:138-144
-  H.N. Shah, V. Kausik, S. Hegde, J.N. Shah, M.B. Bansal. Evaluation of fluid absorption during holmium laser enucleation of prostate by breath ethanol technique. J Urol. 2006;175:537-540
-  A.J. Gross, C. Netsch, S. Knipper, J. Hölzel, T. Bach. Complications and early postoperative outcome in 1080 patients after thulium vapoenucleation of the prostate: results at a single institution. Eur Urol. 2013;63:859-867
-  J. Bae, S.J. Oh, J.S. Paick. The learning curve for holmium laser enucleation of the prostate: a single-center experience. Korean J Urol. 2010;51:688-693
-  M. Ritter, P. Krombach, C. Bolenz, A. Martinschek, T. Bach, A. Haecker. Standardized comparison of prostate morcellators using a new ex-vivo model. J Endourol. 2012;26:697-700
-  J.N. Cornu, J.B. Terrasa, B. Lukacs. Ex vivo comparison of available morcellation devices during holmium laser enucleation of the prostate through objective parameters. J Endourol. 2014;28:1237-1240
-  A.M. Elshal, R. Mekkawy, M. Laymon, A. El-Assmy, A.R. El-Nahas. Towards optimizing prostate tissue retrieval following holmium laser enucleation of the prostate (HoLEP): assessment of two morcellators and review of literature. Can Urol Assoc J. 2015;9:618-625
-  P. Gilling. Holmium laser enucleation of the prostate (HoLEP). BJU Int. 2008;101:131-142
-  S.H. Lee, J.I. Choi, K.Y. Moon, W. Na, J.B. Lee. Holmium laser enucleation of the prostate: modified morcellation technique and results. Korean J Urol. 2012;53:779-784
-  Y. Tang, J. Li, C. Pu, Y. Bai, H. Yuan, Q. Wei, P. Han. Bipolar transurethral resection versus monopolar transurethral resection for benign prostatic hypertrophy: a systematic review and meta-analysis. J Endourol. 2014;28:1107-1114
-  E.A. Elzayat, M.M. Elhilali. Holmium laser enucleation of the prostate (HoLEP): the endourologic alternative to open prostatectomy. Eur Urol. 2006;49:87-91
-  T. Hermanns, N.C. Grossmann, M.S. Wettstein, et al. Absorption of irrigation fluid occurs frequently during high power 532 nm laser vaporization of the prostate. J Urol. 2015;193:211-216
-  T. Hermanns, C.D. Fankhauser, L.J. Hefermehl, et al. Prospective evaluation of irrigation fluid absorption during pure transurethral bipolar plasma vaporisation of the prostate using expired-breath ethanol measurements. BJU Int. 2013;112:647-654
-  P. Stucki, L. Marini, A. Mattei, K. Xafis, M. Boldini, H. Danuser. Bipolar versus monopolar transurethral resection of the prostate: a prospective randomized trial focusing on bleeding complications. J Urol. 2015;193:1371-1375
-  R.E. Jackson, N.F. Casanova, L.P. Wallner, et al. Risk factors for delayed hematuria following photoselective vaporization of the prostate. J Urol. 2013;190:903-908
-  E. Elzayat, E. Habib, M. Elhilali. Holmium laser enucleation of the prostate in patients on anticoagulant therapy or with bleeding disorders. J Urol. 2006;175:1428-1432
-  E.K. Mayer, S.G. Kroeze, S. Chopra, A. Bottle, A. Patel. Examining the ‘gold standard’: a comparative critical analysis of three consecutive decades of monopolar transurethral resection of the prostate (TURP) outcomes. BJU Int. 2012;110:1595-1601
-  C.R. Chapple, N.I. Osman, L. Birder, et al. The underactive bladder: a new clinical concept?. Eur Urol. 2015;68:351-353
-  M. Audouin, S. Benbouzid, J.B. Terrasa, et al. Evaluation of postoperative symptoms after Greenlight™ photovaporization of the prostate through a dedicated questionnaire [in French]. Prog Urol. 2016;26:108-114
-  B. Lukacs, J. Loeffler, F. Bruyère, et al. Photoselective vaporization of the prostate with GreenLight 120-W laser compared with monopolar transurethral resection of the prostate: a multicenter randomized controlled trial. Eur Urol. 2012;61:1165-1173
-  Grabe M, Bartolletti R, Bjerlund TE, et al. EAU guidelines on urological infections. European Association of Urology Web site. http://uroweb.org/wp-content/uploads/EAU-Guidelines-Urological-Infections-v2.pdf.
-  M.G. Lucas, R.J. Bosch, F.C. Burkhard, et al. EAU guidelines on surgical treatment of urinary incontinence. Eur Urol. 2012;62:1118-1129
-  L.B. Lerner, M.D. Tyson, P.J. Mendoza. Stress incontinence during the learning curve of holmium laser enucleation of the prostate. J Endourol. 2010;24:1655-1658
-  F. Endo, Y. Shiga, S. Minagawa, et al. Anteroposterior dissection HoLEP: a modification to prevent transient stress urinary incontinence. Urology. 2010;76:1451-1455
-  A.E. Krambeck, S.E. Handa, J.E. Lingeman. Experience with more than 1,000 holmium laser prostate enucleations for benign prostatic hyperplasia. J Urol. 2010;183:1105-1109
-  H.M. Elmansy, A. Kotb, M.M. Elhilali. Is there a way to predict stress urinary incontinence after holmium laser enucleation of the prostate?. J Urol. 2011;186:1977-1981
-  D.C. Parker, J. Simhan. Management of complications after surgical outlet reduction for benign prostatic obstruction. Can J Urol. 2015;22:88-92
-  W. Zheng, G. Vilos, S. McCulloch, P. Borg, J.D. Denstedt. Electrical burn of urethra as cause of stricture after transurethral resection. J Endourol. 2000;14:225-228
-  M. Gacci, I. Eardley, F. Giuliano, et al. Critical analysis of the relationship between sexual dysfunctions and lower urinary tract symptoms due to benign prostatic hyperplasia. Eur Urol. 2011;60:809-825
-  A. Chung, H.H. Woo. Preservation of sexual function when relieving benign prostatic obstruction surgically: can a trade-off be considered?. Curr Opin Urol. 2016;26:42-48
-  J. Sønksen, N.J. Barber, M.J. Speakman, et al. Prospective, randomized, multinational study of prostatic urethral lift versus transurethral resection of the prostate: 12-month results from the BPH6 study. Eur Urol. 2015;68:643-652
-  A. Collado, G.E. Chéchile, J. Salvador, J. Vicente. Early complications of endoscopic treatment for superficial bladder tumors. J Urol. 2000;164:1529-1532
-  B.K. Hollenbeck, D.C. Miller, D. Taub, et al. Risk factors for adverse outcomes after transurethral resection of bladder tumors. Cancer. 2006;106:1527-1535
-  A.M. Nieder, D.S. Meinbach, S.S. Kim, M.S. Soloway. Transurethral bladder tumor resection: intraoperative and postoperative complications in a residency setting. J Urol. 2005;174:2307-2309
-  T.S. Feng, S. Rusnack, J. Kaminski, P. Fleshner. Appendicovesical fistula following transurethral resection of bladder tumor with mitomycin C. Urology. 2016;89:e1-e2
-  K.A. Richards, N.D. Smith, G.D. Steinberg. The importance of transurethral resection of bladder tumor in the management of nonmuscle invasive bladder cancer: a systematic review of novel technologies. J Urol. 2014;191:1655-1664
-  A. Skolarikos, M. Chrisofos, N. Ferakis, A. Papatsoris, A. Dellis, C. Deliveliotis. Does the management of bladder perforation during transurethral resection of superficial bladder tumors predispose to extravesical tumor recurrence?. J Urol. 2005;173:1908-1911
-  S. Golan, J. Baniel, D. Lask, P.M. Livne, O. Yossepowitch. Transurethral resection of bladder tumour complicated by perforation requiring open surgical repair - clinical characteristics and oncological outcomes. BJU Int. 2011;107:1065-1068
-  Y. Bai, L. Liu, H. Yuan, et al. Safety and efficacy of transurethral laser therapy for bladder cancer: a systematic review and meta-analysis. World J Surg Oncol. 2014;12:301
-  M.W. Kramer, M. Wolters, H. Cash, et al. Current evidence of transurethral Ho:YAG and Tm:YAG treatment of bladder cancer: update 2014. World J Urol. 2015;33:571-579
-  M.W. Kramer, J.J. Rassweiler, J. Klein, et al. En bloc resection of urothelium carcinoma of the bladder (EBRUC): a European multicenter study to compare safety, efficacy, and outcome of laser and electrical en bloc transurethral resection of bladder tumor. World J Urol. 2015;33:1937-1943
-  S.Y. Cho. Current status of flexible ureteroscopy in urology. Korean J Urol. 2015;56:680-688
-  E. Perez Castro, P.J. Osther, V. Jinga, et al., CROES Ureteroscopy Global Study Group. Differences in ureteroscopic stone treatment and outcomes for distal, mid-, proximal, or multiple ureteral locations: the Clinical Research Office of the Endourological Society ureteroscopy global study. Eur Urol. 2014;66:102-109
-  L. Cindolo, P. Castellan, C.M. Scoffone, et al. Mortality and flexible ureteroscopy: analysis of six cases. World J Urol. 2016;34:305-310
-  O. Traxer, G. Wendt-Nordahl, H. Sodha, et al. Differences in renal stone treatment and outcomes for patients treated either with or without the support of a ureteral access sheath: the Clinical Research Office of the Endourological Society Ureteroscopy Global Study. World J Urol. 2015;33:2137-2144
-  A. Breda, A. Territo, J.M. López-Martínez. Benefits and risks of ureteral access sheaths for retrograde renal access. Curr Opin Urol. 2016;26:70-75
-  O. Traxer, A. Thomas. Prospective evaluation and classification of ureteral wall injuries resulting from insertion of a ureteral access sheath during retrograde intrarenal surgery. J Urol. 2013;189:580-584
-  Mitsuzuka K, Nakano O, Takahashi N, Satoh M. Identification of factors associated with postoperative febrile urinary tract infection after ureteroscopy for urinary stones. Urolithiasis. In press.
-  Moses RA, Ghali FM, Pais VM Jr, Hyams ES. Unplanned hospital return for infection following ureteroscopy: can we identify modifiable risk factors? J Urol. In press. http://dx.doi.org/10.1016/j.juro.2015.09.074
-  R. Flannigan, W.H. Choy, B. Chew, D. Lange. Renal struvite stones–pathogenesis, microbiology, and management strategies. Nat Rev Urol. 2014;11:333-341
-  A. D’Addessi, P. Bassi. Ureterorenoscopy: avoiding and managing the complications. Urol Int. 2011;87:251-259
-  A. Unsal, U. Oguz, A. Tuncel, et al. How to manage total avulsion of the ureter from both ends: our experience and literature review. Int Urol Nephrol. 2013;45:1553-1560
a Department of Urology, Rouen University Hospital and University of Rouen, Rouen, France
b Department of Urology and Urological Oncology, Hanover Medical School, Hanover, Germany
c Department of Urology, Tenon Hospital, Pierre and Marie Curie University, Paris, France
d James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
Corresponding author. Department of Urology, Rouen University Hospital, 1 Rue de Germont, 76031 Rouen Cedex 1, France. Tel. +33 0 232880341; Fax: +33 0 232880441.
☆ Cornu, and Hermann did the literature search Cornu led the data analysis. Cornu drafted the manuscript Traxer and Matlaga reviewed the manuscript for critical intellectual content and supervised the work.
© 2016 European Association of Urology, Published by Elsevier B.V.