Postoperative Appearance and Complications of the Urinary Tract Following Surgery: A Comprehensive Review

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Postoperative Appearance and Complications of the Urinary Tract Following Surgery: A Comprehensive Review Poster No.: C-2137 Congress: ECR 2018 Type: Authors: Keywords: DOI: Educational Exhibit N. Kinger 1, P. Mittal 2 ; 1 Atlanta, Georgia/US, 2 Atlanta/US Urinary Tract / Bladder, Anatomy, CT, Fluoroscopy, MR, Complications, Neoplasia, Retroperitoneum 10.1594/ecr2018/C-2137 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 20

Learning objectives To demonstrate the appearance of the urinary tract, including the kidneys, ureters, and bladder, after surgery. To illustrate a variety of postsurgical changes of the urinary tract including nephrectomies and urinary diversions. To demonstrate postoperative complications of the urinary tract. Images for this section: Table 3: Learning Objectives Page 2 of 20

Emory University School of Medicine - Atlanta/US Page 3 of 20

Background A variety of pathologies including malignancy, trauma, infection, and congenital abnormality result in the surgical intervention of the urinary tract. These interventions include resections or even creating a new type of urinary system. As a result, the resulting postsurgical changes of the urinary tract are of importance to clinicians in evaluating urinary system function. Complications of surgical intervention of the urinary system include both acute and chronic pathologies, including urinary leak, stone formation, and stricture. Images for this section: Table 4: Background Emory University School of Medicine - Atlanta/US Page 4 of 20

Findings and procedure details 1. Kidneys and Ureters 1.1 Partial Nephrectomy Partial nephrectomy is a treatment strategy for small renal cancers that decreases the severity of morbidity associated with complete nephrectomies, such as chronic kidney disease and cardiovascular disease Involves removal of a portion of kidney containing tumor (Fig. 1-2) Alternatives include total nephrectomy or radiofrequency ablation Common complications of partial nephrectomy include hematoma, urine leak, abscess, recurrence, iatrogenic arterial pseudoaneurysm, etc. Fig. 1: Left renal partial nephrectomy with clips. Fig. 2: Left renal partial nephrectomy. 1.2 Nephrostomy A nephrostomy is a form of urinary diversion This is often done percutaneously by radiologists Indications include urinary tract obstruction often secondary to renal stones or malignancy, need for urinary diversion, need for treatment, or diagnostic testing (Fig. 3-4) A drain is placed into the renal pelvis and allowed to communicate with the skin surface (Fig. 5) Fig. 3: Right sided percutaneous nephrostomy done for distal urinary obstruction secondary to renal stones. Residual left sided renal stones (yellow arrow). Fig. 4: Right sided percutaneous nephrostomy with gas in right renal pelvis from recent procedure (yellow arrow). Page 5 of 20

Fig. 5: Percutaneous nephrostomy tubes going to skin surface (yellow arrow). 1.3 Ureteroneocystostomy with Psoas Hitch Psoas hitch is done when the ureteral reimplantation/ureteroneocystostomy is not possible due to ureteral resection or stricture preventing distal ureteral reimplantation (Fig. 6). Involves pulling up the bladder and attaching/hitching to the psoas muscle (Fig. 7). The ureter can then be reimplanted Fig. 6: Shortened right ureter (yellow arrow). Normal length left ureter (white arrow). Fig. 7: Patient with history of testicular cancer status post partial cystectomy with psoas hitch and right ureteral reimplantation. Bladder is brought up and attached to psoas muscle (yellow arrow). 1.4 Boari Flap The Boari flap can be done as an alternative to the psoas hitch to reduce distance between the ureter and the bladder Involves detubularizing a flap of bladder and then bringing it up to the ureter where they are attache (Fig. 8) Can be used for long segment ureteral abnormalities (Fig. 9) Fig. 8: Shortened right ureter (yellow arrow). Detubularized bladder flap (white arrow). Bladder (blue arrow). Fig. 9: Right sided Boari flap in female with history of congenital right megaureter and infection. Page 6 of 20

1.5 Suprapubic Cystostomy These are known as a suprapubic catheter This type of procedure involves making a tract from bladder to skin surface, generally for use with a catheter (Fig. 10-11) Can be used for distal obstruction such as by prostate or neurogenic bladder Fig. 10: Decompressed bladder with catheter balloon (yellow arrow) in a patient with prostate cancer Fig. 11: Catheter tract to surface 2. Urinary Diversion Following renal, ureteral, or bladder intervention it is often necessary to create another way for urine to exit the body. Often this is done through a urinary diversion. There are two types of urinary diversions: 1. Continent - In continent urinary diversion the patient has control over function either using his/her own urethra or self catheterizing. 2. Incontinent - In incontinent urinary diversions, the patient is not able to have control over urinary function and the urine can exit the bladder in a variety of ways Table 5: Urinary Diversions 2.1 Indiana Pouch Most common form of continent urinary diversion Formation: 1. It is made from extracting the terminal ileum, cecum and a length of the ascending colon (Fig. 12) 2. An incision is made in the circular intestinal wall to reduce peristaltic activity Page 7 of 20

3. The ileum is then mobilized to form the stoma (Fig. 13) This diversion includes the ileo-cecal valve which helps prevent involuntary loss of urine Fig. 12: Mobilized proximal colon in the right lower quadrant (yellow arrow) Fig. 13: Terminal ileum is used as the ostomy (yellow arrow). The ileo-cecal valve is preserved in the diversion. 2.2 Mitrofanoff appendicovesicostomy Continent cutaneous diversion Appendix is used as reservoir between bladder and skin surface usually with exit at the umbilicus (Fig. 14-15) Allows for self catheterization and hence often used in patients requiring frequent self catheterization Fig. 14: Appendix (yellow arrow) as conduit to surface Fig. 15: Appendicovesicular junction (yellow arrow) 2.3 Studer Bladder Most common form of neobladder Formation: 1. It is made from extracting the ileum upstream from the ileocecal valve 2. The proximal portion is incised and used to create a pouch while the distal portion maintains its small bowel characteristics (Fig. 16) 3. The ureters are placed into the distal portion while the newly created pouch is anastomosed to the urethra (Fig. 17) The use of the patient's own urethra helps prevent involuntary loss of urine Page 8 of 20

Fig. 16: Ileal pouch (yellow arrow) Fig. 17: The newly formed ileal pouch is anastomosed to the native urethra (yellow arrow) 2.4 Hautmann Pouch W shaped form of neobladder Formation 1. It is made from extracting the ileum upstream from the ileocecal valve 2. The loop of bowel is then incised to reduce peristaltic activity and folded into a W shape. A small portion of ileum is allowed to maintain its normal shape. The urethra will be attached to this U segment (Fig. 18) 3. The ureters and urethra are placed into the neobladder and the limbs are sown together. The use of the patient's own urethra helps prevent involuntary loss of urine (Fig. 19) Fig. 18: Both ureters are placed into a W shaped reservoir (yellow arrow) Fig. 19: The native urethra is still used. In this case the native urethra contains a catheter (yellow arrow) 2.5 Ileal Conduit Most common form of urinary diversion Formation 1. It is made from extracting a short segment of ileum and using this portion as an ileal conduit. The ureters are implanted into the ileal segment/neobladder 2. The end towards which peristalsis is directed is made into an ostomy at the right lower quadrant abdominal wall (Fig. 20-21) Page 9 of 20

3. The terminal ileum is not used and the ileocecal valve is preserved within the gastrointestinal tract. Fig. 20: The peristalsing end of the ileum is made into a cutaneous ostomy Fig. 21: Isolated ileal segment acts as the urine conduit 2.6 Cutaneous Ureterostomies The ureters are brought directly to the skin surface (Fig. 22-23). One or both of the ureters may be used. Fig. 22: Scout imaging shows both ureteral stents (yellow arrows) being brought to the skin surface Fig. 23: Cutaneous ureterostomies (yellow arrow) 3 Complications Acute 1. Urine leak/urinoma 2. Bowel injury 3. Infection/abscess 4. Hematoma/seroma 5. Lymphocele Late 1. Stricture 2. Stones 3. Bowel Obstruction 3.1 Urine Leak Page 10 of 20

Urine leaks can occur anywhere along the course of the urinary system. Most common cause is trauma but can also be caused by anatomic problems, malignancy, and importantly surgery (Fig. 24)Leakage of contrast Renal leaks: often can resolve spontaneously, but may require percutaneous drainage Ureter leaks: require diversion or stenting Bladder leaks: Require surgical repair and close management (Fig. 25). Fig. 24: Pelvic hematoma (yellow arrow) after hysterectomy Fig. 25: Leakage of contrast (yellow arrow) demonstrating urine leak 3.2 Calculi Within Urinary Diversion A common complication or result after both continent and incontinent urinary diversion. Incidence ranges from 3 to 43% Some studies have demonstrated differences in type of diversion with Kock pouch showing greater stone formation than Indiana pouch Stones are often either metabolic or infectious Management depends on location: Kidney: PCNL for large stones and ESWL for smaller stones Ureter: Retrograde and/or anterograde access (Fig. 26) Reservoir (Fig. 27): 1. Cutaneous: Trans stomal, percutaneous, or ESWL 2. Orthotopic: Retrograde/transurethral, percutaneous, or ESWL Often there is stone recurrence Fig. 26: Cecal reservoir/indiana pouch stone (yellow arrow) Fig. 27: Ureteral stone (yellow stone) 3.3 Ureteral Stricture (Fig. 28-30) Page 11 of 20

Complication of urinary diversion/cystectomy, which can lead to renal failure One study demonstrated this to occur in 13% of patients with most asymptomatic Management includes stenting, dilating, or creating a new anastomosis. Fig. 28: Reservoir (white arrow). Normal right ureter with contrast (yellow arrow). Strictured left ureter with surrounding stranding and lack of contrast (blue arrow). Fig. 29: Narrowing of left ureter compatible with stricture (yellow arrow) Fig. 30: Narrowing of left ureter compatible with stricture (yellow arrow) 3.4 Ileal Conduit with Bowel Obstruction Can be secondary to adhesions or due to ileal-ileal anastomosis edema or stricture (Fig. 31-32). Fig. 31: Ileal conduit (yellow arrow). Dilated loops of small bowel (blue arrow). Fig. 32: Right lower quadrant transition point felt to be due to adhesions (yellow arrow) 3.5 Ileal Conduit with Pyelonephritis Infection is a common complication of urinary diversion. One study showed that 25% of patients with urinary diversion had pyelonephritis within 5 years (Fig. 33-35). Incontinent urinary diversions are felt to have higher risk than continent due to lack of antireflux mechanisms. Nonorthotopic urinary diversions are felt to be at increased risk due to need for frequent self catheterizations Symptomatic patients should be treated Page 12 of 20

Prophylactic antibiotics are suggested in patients with incontinent urinary diversions and recurrent pyelonephritis Prophylactic treatment is suggested for patients with bacteriuria growing urease positive organisms to prevent stone formation Fig. 33: Right sided perinephric stranding (yellow arrow). Right sided peri-ureteral stranding (blue arrow). Fig. 34: Right sided perinephric stranding (yellow arrow), which is asymmetric. Bilateral hydronephrosis. Fig. 35: Stone within the right lower quadrant ileal conduit (yellow arrow) causing the upstream obstruction. 3.6 Urinoma Urine leak is estimated to occur in 2-10% of patients with ileal conduit formation Leakage of urine can result in fibrosis and stricture Delayed phase imaging is important to show contrast extravasating or filling a urinoma (Fig. 36-38) A urinoma may be secondary to urine leak It is important to differentiate a urinoma from other types of fluid collections such as abscesses A urinoma will often have high levels of creatinine as demonstrated by fluid sampling These may become superinfected (Fig. 39) Fig. 36: Small amount of fluid adjacent to right lower quadrant neobladder (yellow arrow) Fig. 37: Gradual leakage of contrast on delayed phase imaging (yellow arrow) Page 13 of 20

Fig. 38: Contrast filling extraluminal collection (yellow arrow) Fig. 39: Partial filling of a fluid collection with air at the ileo-ureteral anastomosis on delayed phase imaging (yellow arrow). Adjacent abscess (blue arrow). 3.7 Fat Infarct Surgery can cause inflammatory changes within the peritoneum These changes can include necrosis of the mesenteric fat (Fig. 40) This should be differentiated from other causes of inflammation such as abscess Fig. 40: Well defined area of spherical inflammatory stranding (yellow arrow) adjacent to the Indiana pouch 3.8 Neobladder Perforation Rare but feared complication of urinary diversion (Fig. 41) Often presents with abdominal pain and fever Requires surgical treatment Spontaneous rupture can occur secondary to blunt trauma, adhesions or even over distension of the bladder Fig. 41: Extravasation of contrast material from the neobladder (yellow arrow). Debris within the neobladder (blue arrow). 3.9 Lymphocele Uniform fluid collection with thin walls (Fig. 42) It is located near areas of lymph node dissection (Fig. 43) Lymphoceles can resolve by themselves Large lymphoceles may require drainage Important to differentiate from abscess, hematoma, or urinoma (Fig. 44). Page 14 of 20

Fig. 42: Ileal conduit (blue arrow). Thinned walled fluid collection (yellow arrow) with homogenous internal density. Fig. 43: Fluid collection near surgical clips (yellow arrow) Fig. 44: Does not fill or have peripheral enhancement on delayed images Conclusion The urinary tract can take on many different forms following surgery. As a result, it is important for the radiologist to understand the anatomy of the postsurgical urinary system. Understanding postoperative anatomy can help the radiologist identify acute and late complications of surgery. Accurate diagnosis of urinary tract surgery complications is important for timely treatment. Images for this section: Page 15 of 20

Table 6: Conclusion Emory University School of Medicine - Atlanta/US Page 16 of 20

Personal information Images for this section: Table 7: Contact Emory University School of Medicine - Atlanta/US Page 17 of 20

References 1. Catala, Violeta, Marta Sola, Jaime Samaniego, Teresa Marta, Jorge Huguet, Juan Palou, and Pablo De La Torre. "CT Findings in Urinary Diversion after Radical Cystectomy: Postsurgical Anatomy and Complications." RadioGraphics 29.2 (2009): 461-76. Web. 2. Falagas, Matthew E., and Paschalis I. Vergidis. "Urinary Tract Infections in Patients With Urinary Diversion." American Journal of Kidney Diseases 46.6 (2005): 1030-037. Web. 3. Gakis, Georgios, and Arnulf Stenzl. "Ileal Neobladder and Its Variants." European Urology Supplements 9.10 (2010): 745-53. Web. 4. Gill, J. D., J. E. I. Cast, P. J. Thomas, and M. S. Simms. "Orthotopic Neobladder Perforation: An Unusual Presentation of Small Bowel Obstruction." Journal of Surgical Case Reports 2013.7 (2013): n. pag. Web. 5. Kearney, Gary E., Steven G. Docimo, Christopher J. Doyle, and Edward M. Mahoney. "Cutaneous Ureterostomy in Adults." Urology 40.1 (1992): 1-6. Web. 6. Lockhart, Alexandre, Jeff King, Lucas Wiegand, Rafael Carrion, Raul Ordorica, Jorge Lockhart, and Alejandro R. Rodriguez. "Cutaneous Ureterostomy Technique for Adults and Effects of Ureteral Stenting: An Alternative to the Ileal Conduit." The Journal of Urology 186.5 (2011): 1939-943. Web. 7. Moomjian, Lauren N., Laura R. Carucci, Georgi Guruli, and Adam P. Klausner. "Follow the Stream: Imaging of Urinary Diversions." RadioGraphics 36.3 (2016): 688-709. Web. 8. Philip, Joe, Ramaswamy Manikandan, Suresh Venugopal, John Desouza, and Pradip M. Javla. "Orthotopic Neobladder versus Ileal Conduit Urinary Diversion after Cystectomy # A Quality-of-Life Based Comparison." The Annals of The Royal College of Surgeons of England 91.7 (2009): 565-69. Web. Images for this section: Page 18 of 20

Table 8: References Emory University School of Medicine - Atlanta/US Page 19 of 20

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