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ENDOLUMINAL CONTR AST FOR ABDOMEN AND PELVIS MRI: WHEN, WHERE, AND HOW?
Mohit Gupta, MD; Gaurav Khatri, MD; April Bailey, MD; Daniella F. Pinho, MD; and Ivan Pedrosa, MD
Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
PURPOSE
Scleroderma
Figure 2. Coronal 2D thick
slab heavily T2-weighted
SSFSE image obtained after
oral administration of 900
mL of barium-based oral
contrast (Volumen®) followed
by 450 mL of water depicts
diffuse smooth bowel wall
dilation and “stack of coin”
appearance of the proximal
bowel folds, consistent with
the patient’s suspected
diagnosis of scleroderma
(i.e. patient had skin lesions
consistent with this diagnosis).
••Describe the various endoluminal contrast agents available
for magnetic resonance (MR) imaging in the abdomen and
pelvis.
••Highlight specific clinical scenarios where endoluminal
contrast agents may help delineate anatomy and identify
pathology.
••Illustrate incorporation of endoluminal contrast agents
into clinical protocols and workflow for MR imaging of the
abdomen and pelvis.
Type of Agent
Positive Enteric
Examples
Signal IntensityT1W images
Signal Intensity T2W images
Dilute gadolinium, high-fat
milk, ferric ammonium
citrate, iron phytate,
manganese chloride
Negative Enteric
Superparamagnetic Iron
Oxide (ferumoxsil),
blueberry/pineapple juice
Biphasic Enteric
Water, Polyethylene Glcycol
(PEG), Barium sulfate,
mannitol/sorbitol solutions
Endorectal
Ultrasound Gel
Active Colitis With Intramural Sinus Tract Formation
Ultrasound Gel
Intravesical
Water
Table 1: Endoluminal Contrast Agents
ORAL CONTRAST
POSITIVE ENTERIC AGENTS
Limited use due to artifact on T1-weighted images and poor
identification of intraluminal pathology and subtle mucosal/
wall enhancement.
NEGATIVE ENTERIC AGENTS
Limited use due to availability, cost, and patient tolerance.
Oral ferumoxsil used to reduce the signal from surrounding
bowel on MRCP (not currently available in the US).
BIPHASIC ENTERIC AGENTS
Most commonly used due to good delineation of both
luminal and wall pathology.
■■ Water, Polyethylene Glycol (PEG), low-concentration
barium sulfate (Volumen®, E-Z-EM, Westbury, NY).
Potential applications
■■ Intraluminal and extraluminal manifestations of
inflammatory bowel disease (wall thickening,
mucosal abnormalities, strictures, fistulae, leaks).
■■ Delineate bowel neoplasms and autoimmune
diseases.
Technique
■■ Ingest 900cc of barium sulfate solution over
45minutes followed by 450cc of water prior to start
of exam.
••
••
A
B
C
B
Figure 11. Rectovaginal fistula in a 67-year old female with stage IV rectal
carcinoma and history of pelvic radiation. Sagittal 2D T2-weighted FSE
image after administration of 60 mL of endoluminal vaginal ultrasound
gel depicts a 5 mm wide rectovaginal fistula (arrow) approximately 4.5 cm
from the anal verge. Ultrasound gel instilled in the vagina is seen extending
into the rectum.
Peutz-Jegher’s Syndrome
••
••
Intraluminal And Extraluminal Manifestations of
Crohn’s Disease
A
B
Figure 4A and 4B. 26 year-old female with Peutz-Jegher’s Syndrome.
Coronal bSSFP image performed after ingestion of 900 mL of bariumbased oral contrast and 450 mL of water depicts polypoid filling
defect in a lower abdominal bowel loop (A). Coronal post contrast fat
suppressed T1-weighted 3D SPGR image after administration of 5 mL
gadolinium confirms an enhancing 3cm polyp in the small bowel (B).
1 mg of glucagon was administered for anti-peristaltic effect prior to
acquisition of these images.
ENDORECTAL CONTRAST
ULTRASOUND GEL
Shown to improve performance of MR defecography.
Although controversial, may be valuable in rectal cancer
patients with small tumors, polypoid tumors, and history of
prior treatment.
May falsely decrease distance between rectal tumor and
mesorectal fascia (circumferential resection margin) – not
recommended for low tumors.
Technique – Patient is placed in left lateral decubitus position;
60-120 mL of warm ultrasound gel instilled via catheter-tip
syringe.
GADOLINIUM ENEMA
Detection of intraluminal manifestations or small occult sinus
tracts/fistulae in inflammatory conditions not apparent on
traditional CT or MRI.
Technique – 1:100 concentration; 5 mL of gadolinium in 500 mL
of saline via rubber Foley catheter which is placed to gravity.
••
••
••
B
Figure 1A and 1B. Coronal 2D thick slab heavily T2-weighted
single shot fast spin echo (SSFSE) image obtained after oral
administration of 900 mL of barium-based oral contrast (Volumen®)
followed by 450 mL of water in a patient with active Crohn’s
disease depicts luminal narrowing in the terminal ileum (blue
arrows) due to severe wall thickening/inflammation, demonstrated
in other sequences (not shown). Similar T2-weighted SSFE
acquisition in a second patient with Crohn’s disease after ingestion
of oral contrast preparation demonstrates an enterocolic fistula
(red arrow) in the right lower quadrant.
••
••
••
D
Figure 5A-D. 62 year-old male with active colitis. Axial contrast enhanced
CT (A) demonstrates moderate bowel wall thickening of the sigmoid colon
with pericolonic inflammation. Axial T2-weighted (T2W) Fast Spine Echo
(FSE) image (B) demonstrates similar findings to CT with wall thickening
and heterogeneous signal intensity in the wall. Maximum intensity
projection (MIP) reconstructions of T1-weighted 3D SPGR acquisitions after
rectal administration of diluted gadolinium shows severe irregularity of
the sigmoid (arrows in C) and a “double-track” sign due to intramural sinus
tract formation (arrows in D) which was not readily apparent on CT exam or
on the T2-weighted FSE image.
Figure 3. Contrast-enhanced axial CT (A) performed in a male with
acute abdominal pain shows a possible nodular hyperdense area of
wall thickening (red arrow in A) along the greater curvature of the
stomach (not shown) surrounded by hyperdense fluid, consistent with
hemoperitoneum (yellow arrows). Sagittal balanced steady-state freeprecession (bSSFP) MRI performed a few weeks later using water as oral
contrast agent provided adequate distension and increased intraluminal
signal intensity to confirm the existence of a submucosal nodule (arrow
in B) in the gastric wall. Gadolinium-enhanced sagittal fat suppressed
T1-weighted 3D spoiled gradient echo (SPGR) image confirmed avid
enhancement in the nodule (arrow in C). A gastrointestinal stromal
tumor was confirmed at histopathology after surgery.
••
A
A
C
Gadolinium
C
D
INTRAVESICAL CONTRAST
GADOLINIUM (MR CYSTOGRAM)
••Bladder tumor detection.
••Complications of tumor, radiation, trauma such as leak,
fistulae, or sinus tract formation.
••May be utilized in patients that have contraindication to CT
examination or iodine.
Pelvic Organ Prolapse
E
••Technique – Precontrast imaging, followed by instillation of
F
Figure 8A-F. Coronal (A-D) and axial (E and F) 2D T2-weighted FSE
obtained after endoluminal vaginal administration of 60 mL of ultrasound
gel in a 30 year-old female with a suspected septate uterus. MRI confirms
the septate uterus configuration (A) and continuation of the septum
through the external os of the cervix (B). A thick septum is also seen in the
vagina (C, D) with a small anterior (E) and a larger posterior (F) component.
A
Rectovaginal Fistula Secondary to Pelvic Radiation
for Rectal Carcinoma
B
Gastrointestinal Stromal Tumor (GIST)
Gadolinium Enema
Endovaginal
A
Complete Septate Uterus With Vaginal Septum
B
C
1:100 concentration of gadolinium (5 mL in 500mL of saline)
via rubber Foley catheter which is placed to gravity.
SALINE (MR CYSTOGRAM)
••For patients with contrast allergies. Good distention
although saline cannot be distinguished from urine.
Transverse Vaginal Septum
Vesicovaginal Fistula Secondary to Pelvic Radiation
for Cervical Cancer
Figure 6A-C. 70 year-old female with suspected cystocele, enterocele,
possible rectocele. bSSFP image in the mid-sagittal plane without rectal
ultrasound gel during maximal strain (A) demonstrates a small enterocele
(red arrow). After instillation of rectal ultrasound gel, bSSFP image in the
mid-saggital plane during early defecation (B) demonstrates a moderate
rectocele (black arrow). bSSFP image in the mid-sagittal plane during
late defecation (C) demonstrates not only a large enterocele (long red
arrow), but also rectal intussusception (green arrow) and a small cystocele
(yellow arrow). Pubococcygeal line is shown for reference in all three
images (blue line).
Figure 12. Fat
suppressed sagittal
T1-weighted 3D SPGR
image after instillation
of diluted gadolinium
(1:100 concentration) via
a Foley catheter depicts
a vesicovaginal fistula in
a 68 year-old female with
cervical cancer statuspost radiation.
ENDOVAGINAL CONTRAST
ULTRASOUND GEL
Provides stable expansion of the vagina.
Improves delineation of the vaginal fornices and cervix.
Potential applications:
■■ Congenital anomalies – septate uterus and vaginal
septum.
■■ Pelvic malignancy – staging and recurrence.
■■ Deep endometriosis – identify posterior implants
difficult to otherwise diagnose due to tight anatomic
space.
■■ Fistula delineation – potential complication of pelvic
radiation, trauma, infection and inflammation.
♦♦ Fistula may be too small to depict significant
amount of signal intensity on T2-weighted
imaging without luminal contrast.
Technique – Instill approximately 30-60 mL of sterile
ultrasound gel via a catheter-tip syringe into the vagina.
••
••
••
A
B
Figure 9A and 9B. 33 year-old female with transverse vaginal septum.
Sagittal 2D T2-weighted FSE image (A) and coronal reconstruction of a
sagittal 3D T2-weighted FSE acquisition (B) demonstrates focal stenosis
of the vaginal lumen due to transverse vaginal septum without complete
obstruction. Instilled contrast traverses the focal areas of stenosis via a tiny
defect (arrows) confirming incomplete septum.
Stage 1 Cervical Cancer W/O Extension Into Vaginal Fornices
CONCLUSION
••Various options and opportunities for use of intraluminal
contrast in MR imaging.
••In certain examinations (MR enterography, MR
defecography), the use of intraluminal contrast is imperative.
••In other cases, may help with the detection of subtle
pathology in the abdomen and pelvis.
••
••Proper use requires knowledge of appropriate indications,
patient preparation, and selection of a proper imaging
protocol.
Deep Endometriosis
Figure 7. Sagittal 2D T2-weighted
FSE image obtained after
endovaginal administration
of 60 mL of ultrasound gel
demonstrates thickening of the
posterior vaginal fornix with
hypointense signal intensity. In
this patient with recurrent pelvic
pain, findings are in keeping with
deep pelvic endometriosis (red
arrow). Additional endometriosis
plaque is seen in the retrouterine
space (yellow arrow).
REFERENCES
Figure 10. Cervical cancer in a 33-year old female. Sagittal 2D T2-weighted
FSE image obtained after administration of 60 mL of endoluminal vaginal
ultrasound. There is expansion of the vagina with good delineation of the
vaginal fornices (yellow arrows). The cervical tumor (red arrow) does not
extend into the fornices. Accurate assessment of degree of vaginal wall
invasion without vaginal distention is very challenging in large cervical
tumor.
1.
Brant WE, Lambert DL. Gastrointestinal Tract, Peritoneal Cavity, and Spleen MR Imaging. In
“Essentials of Body MRI”. Eds. Brant WE, de Lange E. Oxford University Press New York 2012.
2.
Pannu HK, Scatarige JC, Eng J. Comparison of Supine Magnetic Resonance Imaging With and
Without Rectal Contrast to Fluoroscopic Cystocolpoproctography for the Diagnosis of Pelvic Organ
Prolapse. Journal of Computer Assisted Tomography. 2009;33:125-30.
3.
Fiaschetti V, Crusco S, Meschini A, et al. Deeply infiltrating endometriosis: evaluation of retro-cervical
space on MRI after vaginal opacification. European Journal of Radiology 2012. 81: 3638-3645
4.
Kaur H, Choi H, You Y, et al. MR imaging for preoperative evaluation of primary rectal cancer:
practical considerations. Radiographics 2012; 32: 389-409
5.
Olpin J, Hellbrun M. Imaging of Mullerian duct anomalies. Clin Obstet Gynecol 2009; 52 (1): 40-56.
6.
Romero M, Buxbaum J, and Palmer S. Magnetic resonance imaging of the gut: a primer for the
luminal gastroenterologist. Am J Gastroenterol 2014; 109: 497-509.