The quick advancement of technology, improvement in instruments, new energy sources, better optic quality of devices and increased experience with ureteral calculi, ureter and kidney-related conditions in the last decades caused high success in endoscopic operations, and thus, ureteroscopy has become the first choice for ureteral calculi and ureter-related operations [8,9,10]. On the other hand, ureteroscopic operations may cause many complications such as residual calculi, mucosal injury, perforation, bleeding and edema [11]. Ureteral avulsion is a rare but extremely severe complication with a reported percentage of 0-3.75 [12]. The first avulsion case was reported by Hart and Hodge after manipulation with Dormia basket. Risk factors for avulsion are previous manipulations and high calculi load. Complication risk also increases with proximal ureteral calculi after extracorporeal shock wave lithotripsy (ESWL) treatment [13]. In addition to all these factors, basket use, inexperience, thick (> 9F) ureterorenoscope use and ureteral inflammation can also be stated as risk factors [14]. These conditions were stated in studies in the literature. In our cases, ureteral inflammation and > 9F ureterorenoscope use, especially, were prominent.
Predisposing factors are controversial for ureteral avulsion. But observance of intense inflammation in the ureter during ureteroscopy is among the important factors [15]. The presence of inflammatory tissue in proximal or distal ureter or the region where the stone was impacted forms a potential for ureteral wall rupture [16]. Added to this factor, the delicate tensile strength of the region was stated as 457.52–3374 N cm−2 in circumferential direction and as 902.43–122.08 N cm−2 in the longitudinal direction [16]. In our cases, the ureter, especially its distal end, was observed to be inflamed.
Treatment and management of ureteral avulsion are quite challenging. Traditionally, ureteral avulsion is surgically treated and the reconstructive technique changes according to the length and location of ureter. Ureteroneocyctostomy is the general treatment option for distal ureteral injuries. While psoas hitch or boari flap procedures can be preferred for central ureteral injuries, end-to-end anastomoses using D-J stent can be a treatment option for proximal ureteral injuries. Finally, ileal interposition or renal autotransplantation is generally required in large ureteral injuries with a significant amount of tissue loss [17]. If avulsion is noticed in the postoperative period, percutaneous nephrostomy can be located and definitive treatment can be given when the patient is stable [18]. Ureteral avulsion treatment and management are challenging and controversial. In the literature, nephrectomy was also reported as an option for extended ureteral injuries [19], while there are also limited options such as ileal interposition or renal autotransplantation and appendix interposition [20, 21]. But the number of publications on the approach to the ureter totally avulsed at both ends is still limited in the literature [22].
The management of major ureteral injury is always a challenge [23]. It depends on the location and extent of the injury. Renal autotransplantation is considered a suitable option for ureteral injuries, especially in cases with major ureteral length loss. Delayed recognition of injury requires treatment with extended procedures as well as high experience of the urologists. Repair of long-term defect of the ureter, especially of the proximal ureter, is a particularly difficult surgical challenge. No strict recommendations are available about the treatment of long ureteral lesions [24]. Early intervention was preferred in our cases. Transplantation was not considered since surgical experience is important.
Ordon et al. reported three cases they named as “the scabbard avulsion.” Nephrostomy was inserted postoperatively, and nephrectomy was performed in all patients [19]. Ge et al. presented four ureteral avulsion cases, two of which were total ureteral avulsions. One of the cases was treated with autotransplantation, and no problem was noticed in the follow-up. In the other case, pyeloureterostomy was performed and extended omentum was wrapped, but nephrectomy was performed after a 25-month follow-up [5]. Thai et al. reported a series of six ureteral avulsion cases. Five of them had avulsion in UPJ and UVJ. The authors reported that they refused to perform nephrectomy in one patient and performed boari flap in two patients, with ileal interposition and ureteral reimplantation in one patient each [25]. Unsal et al. reported four ureteral avulsion cases and performed boari flap in one half and ureteral reimplantation procedures in the other half of these cases. During the follow-up for ureteral reimplantation patients, one was normal while one had hydronephrosis [3]. Sevinç et al. reported three total ureteral avulsion cases treated with reimplantation and ileal interposition [22]. Grzegółkowski et al. [26] reported that extended length flap from the bladder was used instead of the entire ureter with modified boari flap technique in a total ureteral avulsion case and watertight, tension free anastomosis was performed, and they also reported extended boari flap modification as a possible alternative reconstructive treatment for total ureteral losses.
We also had three “total ureteral avulsion in both ends” cases and treated two of these with ureterocaliostomy + unc + omental flap wrapping and performed boari flap + renal pelvis y–v advancement on the other (Table 1). In our series, we observed that ureteral feeding was provided by wrapping the omentum around total avulsified ureter and we believe that the patient can perform normal ureteral functions and recover more easily as the intestinal system was not intervened. As one of our patients had an extra renal pelvis, we performed y–v advancement from the renal pelvis and a new ureter was formed by rotating boari flap on the bladder. We believe boari flap is a good option, especially in cases in which psoas hitch is not able to reach or a new tube is formed. In this series, we think that it is important to perform ureteral reimplantation, especially in the early period, and to wrap the omental flap all around to feed the re-implanted ureter.
The literature shows that it is suitable to completely wrap the ureter with omental flap in addition to pyeloureterostomy and ureterovesical anastomosis for all full-length ureteral avulsions and that omental flap feeds the avulsified ureter [5, 6]. In line with previous studies and case presentations, we believe that wrapping the avulsified ureter with omental flap and performing pyeloureterostomy and ureterovesical anastomosis would be a good solution for complete ureteral avulsions [27]. We observed that the ureter was relieved on retrograde pyelographies in postoperative patient follow-ups and there was no extravasation in CT urography. Normal ureteral mucosa and good feeding were observed when diagnostic URS was performed for the patient who had total ureteral reimplantation + omental flap in postoperative sixth month. But a functional decrease and partial scar areas were detected on scintigraphy.
In the literature, 55% [17] of 31 cases had avulsion of the right ureter and 45% [14] had it in left ureter. [3,4,5,6,7, 12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27] Two of our cases had right ureter avulsion, and one patient had left ureter avulsion which was in line with the literature.
As a result, ureteral avulsion is hard to manage and is a nightmare for urologists. But it is important to stay calm and to refer the patient to a center experienced in this field or the injury should be cured in a suitable way together with another urologist, and in case of reimplantation, wrapping the re-implanted ureter with omentum to help its nutrition is an important trick. If ureteral avulsion is well managed, the patients can continue their normal lives without needing nephrectomy, although there is an acceptable loss of renal functions.
