Saturday, March 13, 2021

Ureteral Injury at Surgery Case File

Posted By: Medical Group - 3/13/2021 Post Author : Medical Group Post Date : Saturday, March 13, 2021 Post Time : 3/13/2021
Ureteral Injury at Surgery Case File
Eugene C. Toy, MD, Lawrence M. Ross, MD, PhD, Han Zhang, MD, Cristo Papasakelariou, MD, FACOG

CASE 32
A 45-year-old female underwent surgical removal of the uterus (total hysterectomy) for symptomatic endometriosis 2 days previously. She complains of right back and flank tenderness. On examination, her temperature is 102°F, heart rate is 100 beats/min, and blood pressure is 130/90 mmHg. The heart and lung examinations are normal. Her abdomen is slightly tender diffusely, but bowel sounds are normal. The surgical incision appears within normal limits. There is exquisite right costovertebral angle tenderness on palpation. Ultrasound of the kidneys shows marked dilation of the right renal collecting system and dilation of the right ureter.

 What is the most likely diagnosis?
 What is the anatomical explanation for this condition?


ANSWER TO CASE 32:

Ureteral Injury at Surgery
Summary: A 45-year-old female who underwent total abdominal hysterectomy for symptomatic endometriosis 2 days previously has fever of 102°F and exquisite right flank tenderness at the costovertebral angle. The surgical incision appears normal.

• Most likely diagnosis: Injury to the right ureter

• Anatomical explanation for this condition: Probable ligation of the right ureter as it passes inferiorly to the uterine artery within the transverse cervical (cardinal) ligament of the uterus


CLINICAL CORRELATION
Approximately one-half the length of the ureter is located in the pelvis. It is at risk for injury at three pelvic sites during a hysterectomy. If the patient’s ovaries are also removed (oophorectomy) at the time of the hysterectomy, the ureter is at risk where it crosses the common or external iliac vessels to enter the pelvis just medial to the ovarian vessels. The ureter is especially at risk deeper in the pelvis as it courses toward the urinary bladder inferior to the uterine vessels. Lateral extension of uterine pathology into the transverse cervical ligament increases the risk. The third site at which the ureter is at risk is as it passes laterally to the uterine cervix before its entrance into the urinary bladder. Hydronephrosis and/or hydroureter results from ureteral injury, and cystoscopic stent passage is often attempted first to relieve the obstruction, if possible.


APPROACH TO:
The Ureters

OBJECTIVES
1. Be able to draw the abdominal and pelvic courses of the ureter
2. Be able to describe the sites at which the ureter is anatomically narrowed and
at risk during surgery
3. Be able to describe the blood supply to the ureter

DEFINITIONS
HYSTERECTOMY: Surgical removal of the uterus.

URETERAL INJURY: Ligation, laceration, or denuding the ureter leading to ischemia. Ureteral obstruction can also occur from “kinking” of the ureter.

INTRAVENOUS PYELOGRAM: Intravenous dye is injected, and a series of radiographs are taken that incorporate the kidneys, ureter, and bladder. This procedure allows delineation of the anatomical structures and the function of the kidneys.


DISCUSSION
Each ureter is an inferior continuation of the renal pelvis, and the ureteropelvic junction is at the inferior margin of the hilum of the kidney. One-half the total length of the ureter is abdominal, and the remaining half is located in the pelvis. The abdominal ureter descends retroperitoneally on the anterior surface of the psoas muscle, and at about its midpoint it is crossed anteriorly by the gonadal arteries (testicular/ovarian). The left ureter lies at the apex of the mesosigmoid. It enters the pelvis by crossing anterior to the external iliac artery (it may cross the common iliac bifurcation somewhat medially). In females, the ovarian vessels lie just lateral to the ureters as they enter the pelvis. After entering the pelvis, each ureter passes inferoposteriorly, anterior to the internal iliac vessels, to above the ischial spines. The ureters then course anteromedially to the posterior bladder wall. In this course in a female, the ureters pass inferior to the uterine vessels, reaching the uterus from the lateral pelvic wall (mnemonic: “water under the bridge”), and lie approximately 1 cm lateral to the uterine cervix. Externally, the ureters enter the bladder approximately 5 cm apart but course obliquely through the bladder wall such that their internal openings are only 2.5 cm apart (Figure 32-1).

[Each ureter is anatomically narrowed in three locations: the uteropelvic junction (renal pelvis), where the ureters cross the external iliac vessels (pelvic brim), and as the ureters obliquely traverse the bladder wall (ureterovessical junction). Renal stones may lodge at these narrowed points.] Calculi can form anywhere along the trajectory of each ureter: within the kidney (as renal stones), within the ureter proper (ureterolithiasis), or within the narrowest segment of the ureter, inside the bladder (as gallstones). The pelvic portion of the ureters is at surgical risk, especially

Course of the ureter anatomy

Figure 32-1. Course of the ureter. (Reproduced, with permission, from Tanagh EA, McAninch JW, eds. Smith’s General Urology, 12th ed. East Norwalk, CT: Appleton & Lange, 1988.)

in females during hysterectomy procedures. If an oophorectomy is performed with the hysterectomy, the ovarian vessels must be ligated, and each ureter lies just medial to these vessels within the suspensory ligament of the ovary. They may be inadvertently clamped, ligated, or divided at this site. The ureters are at risk as they pass inferiorly to the uterine vessels, in or adjacent to the transverse cervical (cardinal) ligament, where they may also be inadvertently clamped, ligated, or divided. The ureters are at risk in a vaginal hysterectomy as they course just laterally to the uterine cervix.

The arterial blood supply of the ureters is likely to originate from any nearby artery, and its chief supply is derived from ureteral branches from the aorta and the renal, gonadal, common and internal iliac, vesical and uterine arteries. Ureteric branches reach the ureters from their medial side and divide into ascending and descending branches.


COMPREHENSION QUESTIONS

32.1 A 39-year-old woman complains of hematuria and significant flank tenderness. She has a history of kidney stones. A CT scan depicts the abdominal portion of the ureter lying anterior to a muscle. Which of the following is most likely to be the name of this muscle?
A. Psoas
B. Serratus anterior muscle
C. Obturator muscle
D. Rectus muscle
E. External oblique muscle

32.2 A dissection of the ureter is accomplished to excavate a large retroperitoneal mass. In isolating the ureter, the surgeon is attempting to ensure that the blood supply to the ureter is not disrupted. Which of the following best describes the arterial supply to the ureter?
A. Ureteral artery arising from the abdominal aorta
B. Ureteral artery arising from the external iliac artery
C. Ureteral artery arising from the internal iliac artery
D. No specific artery, but rather small branches from the nearby arteries

32.3 A 30-year-old woman is noted to have an absent kidney. Which of the following findings is she also likely to have?
A. Absent unilateral ovary
B. Unicornuate uterus
C. Imperforate hymen
D. Inguinal hernia


ANSWERS
32.1 A. The abdominal ureter lies anterior to the psoas muscle. 
32.2 D. The ureter does not have any specific artery supplying it but rather has small branches from the nearby arteries such as the aorta and renal, gonadal, common and internal iliac, vesical and uterine arteries.
32.3 B. The urinary and paramesonephric ducts are in close proximity anatomically and functionally during embryologic development. Thus, a congenital abnormality in the kidney or ureter often is associated with an abnormality of the ipsilateral tube, uterine horn, or cervix. A unicornuate uterus is a condition in which one mullerian duct does not form or descend normally in embryonic development, leaving only one uterine “horn.” The distal vagina, vulva, and ovary are of different embryonic origin.


ANATOMY PEARL
 The ureters are retroperitoneal along their entire length.
 The ureters are narrowed at three sites: ureteropelvic junction, the crossing of the external iliac artery, and the location where they pass through the bladder wall.
 The ureters are at risk at three pelvic sites: where the ovarian vessels lie just lateral, where they pass inferior to the uterine vessels, and just lateral to the uterine cervix.
 Ureteral arterial branches reach the ureter from their medial side.

References

Gilroy AM, MacPherson BR, Ross LM. Atlas of Anatomy, 2nd ed. New York, NY: Thieme Medical Publishers; 2012:236−237. 

Moore KL, Dalley AF, Agur AMR. Clinically Oriented Anatomy, 7th ed. Baltimore, MD: Lippincott Williams & Wilkins, 2014:292−294, 363−364, 373. 

Netter FH. Atlas of Human Anatomy, 6th ed. Philadelphia, PA: Saunders; 2014: plates 313−314, 316−318.

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