Topics

Topic

design image
Ureters

The ureters are paired muscular tubes, each measuring about 25–30 cm in length, that transport urine from the renal pelvis of the kidneys to the urinary bladder. They originate at the ureteropelvic junction (UPJ), descend retroperitoneally along the posterior abdominal wall, cross over the pelvic brim near the bifurcation of the common iliac vessels, and enter the bladder at the ureterovesical junction (UVJ).

Anatomically, each ureter has three classic sites of narrowing, which are of high clinical importance because they are common sites for urinary stones (urolithiasis):

  1. Ureteropelvic junction (UPJ)

  2. Crossing over the iliac vessels (pelvic brim)

  3. Ureterovesical junction (UVJ)

The ureteral wall consists of three layers: mucosa (transitional epithelium), muscularis (smooth muscle responsible for peristalsis), and an adventitial connective tissue covering. Peristaltic contractions actively propel urine toward the bladder, even against gravity.

Clinically, ureters are important in urinary obstruction, reflux, strictures, urolithiasis, congenital anomalies, and tumors. Their close anatomical relationship to pelvic structures makes them vulnerable to iatrogenic injury during gynecologic, colorectal, and urologic surgeries.

Synonyms

  • Ureteral ducts

Function

  • Transport urine from the renal pelvis to the bladder via peristaltic contractions

  • Prevent urine reflux with a functional oblique entry at the bladder wall

  • Serve as clinical landmarks in stone disease and surgical procedures

MRI Appearance

T1-weighted images:

  • Normal ureteral lumen appears as hypointense or signal void, surrounded by intermediate-signal soft tissue

  • Distended ureter with urine may appear slightly higher signal

T2-weighted images:

  • Fluid-filled lumen is bright hyperintense

  • Thickened wall or obstruction (stones, tumors) is seen as hypointense defects within lumen

STIR:

  • Suppresses fat signal, enhancing visualization of ureteral wall and perivascular edema

  • Highlights inflammation, periureteric fibrosis, or infection

T1 Fat-Saturated (Pre-contrast):

  • Ureteral wall shows intermediate signal, standing out against suppressed fat

  • Lumen is usually hypointense unless filled with proteinaceous or hemorrhagic material

T1 Fat-Saturated Post-Contrast (Gadolinium):

  • Ureteral wall enhances thinly and uniformly in normal cases

  • Pathological enhancement occurs in ureteritis, tumors, or periureteric inflammation

  • Filling defects may indicate stones, tumors, or clots

MRI Non-Contrast 3D Imaging (MR Urography):

  • Provides 3D visualization of ureteral course and lumen

  • Demonstrates hydronephrosis, strictures, and congenital anomalies without contrast

CT Appearance

CT Pre-Contrast (Non-contrast CT KUB):

  • Gold standard for detecting urinary calculi (appear hyperdense)

  • Ureters appear as soft tissue structures coursing retroperitoneally

  • Hydroureteronephrosis can be identified without contrast

CT Post-Contrast (Excretory Phase):

  • Enhances ureteral lumen as contrast is excreted into urine

  • Detects strictures, filling defects, or ureteral wall thickening

  • Demonstrates relationship to adjacent pelvic organs

CT Urography (CTV):

  • Provides optimal evaluation of entire urinary tract

  • Multiplanar reconstructions show ureteral anatomy, strictures, stones, tumors, or post-surgical changes

  • Essential for urothelial carcinoma staging and congenital anomalies

MRI images

ureters MRI coronal image anatomy image -img-00000-00000

MRI images

ureters MRI sag image anatomy image -img-00000-00000_00001

CT image

ureters CT axial image

CT image

ureters CT coronal image

CT image

Ureter MRI pelvis axial anatomy image-img-00000-00000

CT image

Ureter MRI pelvis axial anatomy image-img-00000-00000_00001

CT image

Ureter ct pelvis image