Radiographic Imaging in Inflammatory Bowel Disease.

Dr/ ABD ALLAH NAZEER. MD.

The etiology of ulcerative colitis is unknown, though studies demonstrating a more frequent occurrence within members of the same family .

Ulcerative colitis.

Ulcerative ColitisImaging Modalities

Colon:Plain abdominal X-rayColonoscopyBarium enema(CT)

Abdominal radiographs obtained 2 days apart show mucosal edma and worsening of the distention in the transverse colon.

Ulcerative Colitis with multiple ulcer.

Ulcerative Colitis with lead pipe colon.

Ulcerative Colitis with loss of haustral pattern and lead pipe appearance.

Ulcerative Colitis with thickened sigmoid colon and stranding of the adjacent mesenteric fat.

Ulcerative Colitis with active disease and mural wall enhancement.

Ulcerative Colitis with thickened wall and narrow lumen.

Ulcerative Colitis with pseudo-polyp.

Ulcerative Colitis with multiple stricture segments.

Contracted colon with widespread pseudopolyp formation. There is also a stricture at the hepatic flexure, which was inflammatory.

MRC technique shows wall-thickening patterns in patient with ulcerative colitis, left, and another patient with Crohn's disease, right. Images courtesy of Dr. Pasquale Paolantonio.

UC complications affecting the colon include:Severe bleedingColon perforation (a hole or tear)Toxic megacolon—rapid and dangerous swelling of the colonInflammation from UC may also lead to complications outside the colon, which include:Kidney stonesOsteoporosisArthritisSevere dehydrationInflammation of eyes, skin, and/or joints(Rarely) liver disease.

Crohn,s disease is a chronic granulomatous inflammatory disease of the gastrointestinal tract with a tendency toward remission and relapse. Crohn disease can affect any part of the gastrointestinal tract from the mouth to the anus, often involving multiple discontinuous sites. The small intestine is involved in 80% of cases, most commonly at the terminal ileum. The colon is affected either with (50% of cases) or without (15%–20%) involvement of the small intestine (1). The cause of Crohn disease is not known; however, several factors are believed to be involved, including infections; intestinal mucosal immune system abnormalities; genetic, mesenteric, or vascular alterations; diet and ingested materials; and psychogenic factors (2). Crohn disease is common in northern Europe, North America, and Japan and is becoming more prevalent, with both genders equally affected and peak involvement in persons between 15 and 25 years of age Radiologic findings at this (early) stage include subtle elevations and aphthoid ulcers. As the disease progresses, it extends transmurally to the serosa (transmural stage) and beyond to the mesentery and adjacent organs (extramural stage). Aphthoid ulcers develop into linear ulcers and fissures to produce an ulceronodular or “cobblestone” appearance. The bowel wall is thickened by a combination of fibrosis and inflammatory infiltrates. Bowel obstruction, strictures, abscesses or phlegmon, fistulas, and sinus tracts are common complications of advanced disease.

Mesenteric border ulceration and ileoileal fistula. Image from an air double-contrast enteroclysis study demonstrates typical straightening of the mesenteric border, a finding that indicates linear ulceration or ulcer scar. A relatively long segment of the bowel is affected at several sites, and multiple stenoses are also identified. A fistula (arrow) extends from the ileum to the adjacent ileal loop.

Crohn’s Disease with stricture segment (Sting sign of Kantor) and wide separation between loops.

Magnetic Resonance Imaging (MRI).

Due to differential water content, MRI can differentiate active inflammation from fibrosisThus MRI can distinguish between inflammatory and fibrostenotic lesions in IBDNo radiation exposure is associated with the use of MRI

Traditionally has been used in investigating perianal abscesses and fistulas Role is being expanded as the sensitivity of MRI enteroclysis in the detection of small bowel stenoses in patients with CD rivals that of the SBFT.

Conventional enteroclysis and CT shows Crohn's disease with mural wall enhancement.

Crohn disease demonstrates three concentric circles (red circle) representing hyperemic mucosa and muscularis/serosa as inner and outer high density rings and submucosal edema in the central, low density ring.

Active Crohn lesions at the distal ileum with contiguous involvement from the ascending colon to the sigmoid colon. (a) Coronal reformatted CT scan from 1-mm-thick axial source images clearly shows bowel wall thickening at the distal ileum (arrowheads) and colon (arrows). The thickened wall has a stratified appearance. Increased mesenteric vascularity (“comb sign”) is noted around the involved segment. These findings are suggestive of active lesions from Crohn disease. (b) Gadolinium-enhanced spoiled gradient-echo MR image shows markedly increased enhancement of the involved bowel wall segment and an increased number of mesenteric vessels around the segment (arrows).

Imaging with a gadolinium-enhanced spoiled gradient-echo sequence. (a) Non-fat-suppressed single-shot fast spin-echo MR image shows a Crohn lesion with prominent wall thickening at the distal ileum (arrows). (b, c) On unenhanced (b) and contrast-enhanced (c) spoiled gradient-echo MR images, the involved ileal segment shows intense wall enhancement compared with normal bowel segments, a finding that indicates an inflammatory active lesion.

Pelvic MRI in patient with CD.A: abscess.F: Fistula.

High-grade small bowel obstruction at the distal ileum caused by Crohn disease. Contrast-enhanced axial (a, b) and coronal reformatted (c) CT scans demonstrate luminal narrowing at the distal ileum in a relatively long bowel segment (straight arrows) associated with prominent dilated proximal loops (curved arrow in c). The wall of the involved segment has a stratified appearance associated with an increased number of adjacent mesenteric vessels (comb sign) (arrowheads in a and c).

Prominent wall thickeningComb signMural stratification

Contrast-enhanced CT scan of the lower abdomen shows a proliferation of fat tissue around the ascending colon.

Abscess in the small bowel mesentery.

Iliopsoas muscle and peri-anal abscess.

Mural wall thickening.

Doppler study show increased vascularity.

Endoscopic Ultrasound.

Major disadvantage is that sensitivity is again operator dependent.

Key to figure at right.1: probe.2: dilated balloon.3: Internal Anal Sphincter.4: External Anal Sphincter.5: Intersphincteric Abscess.

Thank You.