Tips and Tricks for Performing a Retrograde Pylogram The technique for performing a retrograde pylogram has varied little since the early 20th century. It was performed to opacify the ureters and intrarenal collecting system by the retrograde injection of contrast material. It has the unique ability to document the normalcy of the ureter distal to the level of obstruction and to better define ureteral abnormalities. The intrarenal collecting system includes the renal calyces, minor and major, and the renal pelvis. Each ureter exits the renal pelvis at approximately L2 to L3 and parallels the spine overlying the transverse processes. One of the first anatomic landmarks is the ureteropelvic junction, UPJ. The ureter then courses anterior to the psoas muscles in the retroperitoneum. The proximal ureter refers to the segment from the UPJ to the superior margin of the sacrum. The mid-ureter is the segment that overlies the sacrum. The distal ureter is the short segment between the inferior margin of the sacrum and the ureteral orifice. The ureter then enters the bladder at the ureterovesical junction, UVJ, or the short segment of ureter that courses through the muscular bladder wall. Indications for a retrograde pylogram include identification of iatrogenic ureteral injuries, evaluation for ureteral obstruction, identification of filling defects secondary to stones or tumors, assistance for stent placement and ureteroscopy, and evaluation of traumatic injuries. There are no absolute contraindications. However, there are a few relative contraindications. Retrograde pylograms should be performed with caution in patients with bacteriuria and avoided if possible. Fluoroscopy may be performed in pregnant patients if the benefits of the procedure outweigh the risks. Usually, patients with a known allergy to contrast material do not have complications as the contrast is rarely absorbed into the bloodstream. Equipment required to perform a retrograde pylogram includes a cystoscope comprised of three components, the telescope with a 30 degree lens, bridge with an endoscopic seal, and most commonly a 22 French rigid sheet. Additionally, a four or five French ureteral catheter is used. Non-obstructing ureteral catheters include open-ended catheters like the one pictured here. Obstructing catheters include cone or wedge tip catheters like the one pictured here. A guide wire may be required depending on surgeon preference. Common contrast agents include Isovu or Omnipaque. You may consider dilating up to 50% with normal saline. This is dependent on surgeon preference. After the patient is placed under general anesthesia, the patient is properly positioned in the dorsal lithotomy position. A C-arm is required and it is important to position the C-arm prior to the procedure. Ensure that there is room under the bed to accommodate the C-arm. A cystoscopy is performed using the rigid cystoscope. The ureteral catheter may be placed through the endoscopic seal at this time. Using the rigid cystoscope, the correct ureteral orifice is identified. An open-ended or cone tip catheter is used to cannulate the ureteral orifice and then advanced into the ureter with its tip positioned in the distal ureter. A guide wire may also be used for assistance. Prior to cannulating the ureteral orifice, the ureteral catheter is flushed to ensure that there are no air bubbles within the lumen that could be falsely mistaken for stones or tumors. Water-soluble contrast is then instilled slowly to gently distend the upper collecting system. Approximately 5 to 8 cc's of contrast is usually needed to pacify the ureter and renal collecting system. Spot images are then obtained from the distal to proximal collecting system in a stepwise fashion. Backflow occurs during retrograde pylography when contrast is injected under pressure and escapes the collecting system. There are various types of backflow dependent on which route the contrast takes. We will now review abnormal findings that may be seen when performing a retrograde pylogram for the following indications. First we will review iatrogenic ureteral injuries. Case 1 is a 43-year-old G3P3 female with a uterine rupture requiring an emergent cesarean section. Patient was transferred after there was an intraoperative concern for ureteral injury and no efflux was noted from the left ureteral orifice during cystoscopy. On retrograde pylogram, a 2-3 cm defect was noted in the distal left ureter. Exploratory laparotomy revealed a left ureteral injury distal to the ovarian pedicle with a monofilament suture transecting the injured portion of the ureter and surrounding tissue changes consistent with thermal injury. A left ureteral neocystostomy was performed. Case 2 is a 33-year-old female with stage 3 pelvic organ prolapse who underwent a total vaginal hysterectomy and uterosacral ligament suspension. After placement of the uterosacral ligament suspension sutures, there was noted to be no efflux from the right ureter with tension on the sutures and after removal of the sutures, brisk clear ureteral efflux was seen. A retrograde pylogram was then performed and extravasation was noted in the distal ureter. Case 3 is a 58-year-old female with a history of rectal cancer and prior chemoradiation and a low anterior resection with complete proctectomy and posterior vaginal wall reconstruction. She presented with the chief complaint of leakage of urine per vagina. Retrograde pylogram showed a ureterovaginal fistula with contrast opacifying the vagina. Now we will review cases involving ureteral obstruction. Case number 4 is a 40-year-old female who presented 3 weeks after a laparoscopic sigmoid colon resection with the chief complaint of left flank pain. A retrograde pylogram was performed of the left kidney demonstrating no contrast passage at the level of the mid-left ureter. An anterograde nephrostogram was then performed which demonstrated moderate hydronephrosis and loss of contrast distal to the mid-ureter. Findings were indicative of a left mid-ureteral injury. Given time since operation, a nephrostomy tube was placed with eventual plan for definitive ureteral reconstruction. Case number 5 is a 42-year-old female with a history of a pelvic exteneration and radiation. She presented with findings of pylonephritis and worsening chronic kidney disease. Patient had a retrograde pylogram and an anterograde nephrostogram performed showing bilateral ureteral stricture disease. This image shows a left proximal ureteral stricture. Retrograde pylograms also show filling defects which can be helpful in identifying stones or tumors. Case number 6 is a 32-year-old male with a chief complaint of left flank pain. CT scan revealed a soft tissue mass in the left ureter. A large irregular filling defect was seen at the level of the mid-ureter. Biopsy showed low-grade transitional cell carcinoma. Additionally, retrograde pylograms are used to help during stent placement and ureteroscopy. Case number 7 is a 53-year-old female with a history of ovarian cancer and distal right ureteral obstruction. A retrograde pylogram was performed to assist in stent placement. A good curl was noted within the left lower moiety and subsequently in the upper pulmoiety. Retrograde pylograms are also beneficial in the evaluation of traumatic ureteral injuries. Case number 8 is a 24-year-old male with a motor vehicle collision who sustained a right grade IV renal injury. Retrograde pylogram revealed an intact ureter with normal caliber. However, extravasation was noted from the mid and upper pulcalices. A ureteral stent was placed. Case number 9 is a 14-year-old male status post gunshot wound to the abdomen requiring small and large bowel resection. He was transferred after developing a tense abdomen and gross hematuria. He was taken to the OR for a retrograde pylogram with extravasation of contrast noted above the pelvic rim. There was no contrast seen proximal to the injury. A right nephrostomy tube was placed. The tips and tricks reviewed here are designed to facilitate successful performance of a retrograde pylogram. Retrograde pylograms can be performed for various indications and are useful in the daily practice of the urologist and urogynecologist.

retrograde pylogram

procedure

ureters

anatomy

abnormal findings