Download Free Medical Inflammatory bowel disease imaging PowerPoint Presentation

Inflammatory bowel disease imaging PowerPoint Presentation

DOWNLOAD MEDICAL POWERPOINT PRESENTATION

About This Presentation

Description : Check out this medical presentation on Radiology and Imaging, which is titled "Inflammatory bowel disease imaging", to know about inflammatory bowel disease imaging.

Tags : Radiology, Imaging, Inflammatory bowel disease

Published on : Jul 28, 2021 | Views : 1450 | Downloads : 8

Shareable Url :

Embed Code :

Comment

Transcript

Slide 1-

Inflammatory bowel disease imaging Dr Karam Manzalawi
Slide 2-

Inflammatory bowel disease (IBD)  is a chronic idiopathic disease affecting the gastrointestinal (GI) tract.  Crohn’s disease (CD) and ulcerative colitis (UC).  ? an exaggerated and inappropriate immune response to gut luminal microbes.  peak age of onset between 15-30 years of age .  up to 20% of people with IBD are diagnosed during childhood.
Slide 3-

Classification  Crohn's disease and ulcerative colitis (UC).  other forms of IBD  Microscopic colitis subdivided into collagenous colitis and lymphocytic colitis  Diversion colitis  Behçet's disease  Indeterminate colitis
Slide 4-

IBD clinical manifestations and treatment strategies  Symptoms of IBD often wax and wane, defining periods of “flare” and “remission”, respectively.  Clinical manifestations of UC include diarrhea, with or without blood, abdominal pain, tenesmus, and fecal Urgency.  manifestations of CD are more variable depending on the extent and location of the GI inflammation. CD with predominantly colonic involvement often presents in similar fashion to UC  whereas in small bowel CD, diarrhea and rectal bleeding are seen less frequently and symptoms such as fever,fatigue and weight loss are common.
Slide 5-

Extraintestinal manifestations  Extraintestinal manifestations, such as arthritis/arthralgias, skin and ocular involvement and hepatobiliary conditions like primary sclerosing cholangitis, occur in more than 1/3 of IBD patients  Linear growth attenuation and pubertal delay are common among children with IBD. Up to 30% of children with CD.  Laboratory abnormalities such as anemia, hypoalbuminemia and elevation in erythrocyte sedimentation rate and C-reactive protein (CRP) can be supportive but are not specific for IBD and are normal in up to 50% of IBD patients at the time of diagnosis
Slide 6-

 The diagnosis of IBD =clinical features +findings on endoscopy and histopathology.  There is no medical cure for CD or UC, but medical therapy is effective in many cases, both at reducing symptoms and at reducing intestinal inflammation.  The classes of medications most commonly used to treat IBD include corticosteroids, antibiotics, anti-inflammatory agents (5-aminosalicylates), immunomodulators (6-mercaptopurine, azathioprine and methotrexate) and newer biologic therapies.
Slide 7-

ppt slide no 7 content not found
Slide 8-

Surgery  Surgery in IBD is typically reserved for medically refractory cases.  In UC, total colectomy with ileal pouch-anal anastomosis is often performed for medically refractory cases or for patients with IBD-associated dysplasia or colorectal cancer but is associated with complications including pouchitis and pouch malfunction/dysfunction.  Intestinal resections in CD are also frequently performed in medically refractory cases but disease recurrence is common if not nearly universal.
Slide 9-

treatment  While treatment goals in practice have traditionally focused on an improvement in clinical symptoms, this improvement alone may not predict underlying disease activity. In CD in particular, the discrepancy between clinical symptoms and active inflammation can potentially lead to unnecessary treatments for patients whose symptoms are not due to active inflammation and to asymptomatic progression of disease and disease-related complications in patients who are without clinical symptoms despite active inflammation.  This discordance has led to a search for additional targets that can be used in combination with clinical symptoms to help guide treatment decisions.
Slide 10-

 Candidate targets include CRP, fecal calprotectin, intestinal appearance on cross-sectional imaging modalities like CT enterography (CTE) and MRE, and mucosal healing based on endoscopic findings, which is becoming a preferred objective measure of disease activity as it correlates well with improved clinical outcomes
Slide 11-

ppt slide no 11 content not found
Slide 12-

Current role of imaging in IBD evaluation  (1) at the time of initial diagnosis to distinguish UC from CD;  (2) to assess and track progression of extraintestinal IBD manifestations;  (3) to visualize penetrating complications of disease that extend outside the bowel wall;  (4) to assess disease activity in patients with known IBD during symptomatic recurrence,
Slide 13-

ppt slide no 13 content not found
Slide 14-

Crohn disease vs ulcerative colitis
Slide 15-

bowel involved  CD: small bowel 70-80%, only 15-20% have only colonic involvement  UC: rectal involvement 95%, with terminal ileum only involved in pancolitis (backwash ileitis)
Slide 16-

Distribution  CD: skip lesions typical.  UC: continuous disease from rectum up.
Slide 17-

ppt slide no 17 content not found
Slide 18-

Gender  CD: no gender preference  UC: male predilection
Slide 19-

colonic wall  fat halo sign seen in 61% of chronic UC cases, but only in 8% of CD  bowel wall is thicker in CD than in UC (when colon involved)  serosal surface smooth in UC (95%), irregular in CD (80%)
Slide 20-

perianal involvement  UC: although rectal involvement is very common, perianal complications are not as frequently seen  CD: common, seen in 82% of patients  stranding of ischiorectal fossa/perirectal fat (73%)  fistulas/sinus tracts (22%)
Slide 21-

mesenteric creeping fat  CD: common in chronic cases.  UC: not seen, as small bowel not involved.
Slide 22-

abscess formation  CD: common, eventually seen in 15-20% of patients  UC: uncommon
Slide 23-

extraintestinal complications  gallstones: seen in 30-50% of CD patients  primary sclerosing cholangitis: more common in UC  hepatic abscess: seen in CD  pancreatitis: more common in CD
Slide 24-

ppt slide no 24 content not found
Slide 25-

ppt slide no 25 content not found
Slide 26-

ppt slide no 26 content not found
Slide 27-

Crohn disease" regional enteritis"  Epidemiology  Clinical presentation
Slide 28-

Radiographic features  The characteristic of Crohn disease is the presence of skip lesions and presence of discrete ulcers
Slide 29-

ppt slide no 29 content not found
Slide 30-

ULTRASOUND limited role, it has been evaluated as an initial screening tool Typically examination is limited to the small bowel and wall thickness assessed: Bowel wall thickness should be <3 mm, normally thickness < 3 mm helps exclude the disease in a low risk patient. thickness > 4 mm helps establish the diagnosis in a high risk patient. Ultrasound in the assessment of extraintestinal manifestations.
Slide 31-

features on ultrasound:  non-compressible, rigid, fixed bowel wall  perienteric fluid  creeping fat - echogenic area (representing proliferation of adipose tissue that extends around active inflammation) separating bowel loops  gut signature - lost or preserved  strictures - fibrotic (maintains gut signature) or inflammatory (loss of gut signature)  abscess  fistula
Slide 32-

ppt slide no 32 content not found
Slide 33-

US image - stricture in a patient with active Crohn's disease
Slide 34-

Advanced Intestinal Mucosal Manifestations of Crohn’s Disease  coarsened and granular appearance of the mucosa  nodular thickening of the valvulae conniventes.  Aphthous mucosal lesions  dilution and/or flocculation of the intraluminal contrast column.
Slide 35-

 Aphthous lesions. 34-year-old woman with diarrhea.  Double contrast barium enema demonstrates diffuse aphthae throughout the colon ( arrowheads ) manifesting as shallow erosions surrounded by a zone of edema
Slide 36-

Advanced Intestinal Mucosal Manifestations of Crohn’s Disease  the ulcers take on a linear conformation, typically only 1–2 mm wide and extending up to 15 cm in length. (along the mesenteric margin)  because it maintains its pliability, the antimesenteric side may appear sacculated when compared to the contracted and rigid mesenteric side
Slide 37-

 Crohn’s disease of the duodenum, with sacculations. 30-year-old woman with diarrhea.  Upper GI study demonstrates  a diffusely diseased duodenum with areas of focal dilation ( arrows ) consistent with sacculations.  Additionally, there are several ulcers ( arrowheads ) and discontinuous segments offocal narrowing
Slide 38-

 deep longitudinal, oblique, and transverse linear ulcers intersect  islands of edematous mucosa, commonly referred to as “pseudopolyps,” may mimic the appearance of nodules protruding beyond the mucosal surface
Slide 39-

ppt slide no 39 content not found
Slide 40-

 Pseudopolyps should be distinguished from true inflammatory polyps, which occur when focal inflammatory cellular infiltrate and edema cause the involved mucosa to project above the level of the neighboring mucosa.  On contrast fluoroscopy, inflammatory polyps will appear as multiple small, rounded luminal filling defects
Slide 41-

 The coexistence of regional mucosal denudation and pseudopolyps gives rise to the characteristic “cobblestone” appearance of advanced Crohn’s disease.  cobblestoning appears as large and irregular regions of mucosal ulceration with interspersed pseudopolyps of variable size and shape. The involved segment of bowel may demonstrate reduced pliability and luminal narrowing
Slide 42-

 Crohn’s ileitis with cobblestone confi guration.  23-year-old woman with chronic diarrhea, malnourishment, and evidence of enteric blood loss. Small bowel follow- through shows loop separation due to severe mural edema as well as transverse ( arrowhead ) and linear ( arrow ) ulcerations involving the distal ileum. The coexistence of pseudopolyps produces the characteristic cobblestone appearance
Slide 43-

 Frayed string appearance. 22-year-old woman with chronic diarrhea diagnosed with Crohn’s disease.  Small bowel follow-through shows contrast traversing a diffusely narrowed segment of distal ileum, resembling the appearance of a frayed string ( arrow ). Note the eccentric involvement of the bowel wall, with sacculations along the antimesenteric margin ( arrowheads )
Slide 44-

Fibroinflammatory Stenosis in Advanced Crohn’s Disease  Intestinal pliability may be compromised in advanced Crohn’s disease by any combination of fibrosis, inflammatory infiltration, and spasm.  Because inflammatory stenosis and spasm may be amenable to medical therapy, whereas fibrous stricture generally requires surgical repair, the radiologist is often called upon to help distinguish between these entities.
Slide 45-

 On contrast fluoroscopy, both inflammatory stenosis and fibrous stricture will appear as luminal narrowing; the classic “string sign” describes a thin column of intraluminal barium within the narrowed segment of bowel that resembles a frayed string.  The key to differentiating stricture :monitoring of luminal distensibility  in fibrous stricture, luminal distensibility is lost ,  in spasm, dispensability is preserved;  in inflammatory stenosis,distensibility should remain at least partially intact
Slide 46-

ppt slide no 46 content not found
Slide 47-

Mesenteric Involvement and Perforating Disease  “creeping fat” may be suspected when bowel loops appear abnormally separated.  fibrosis in the mesentery may result in kinking and fixation of the neighboring small bowel loops.  fistulae and/or sinus tracts :extension of contrast agent beyond the expected boundaries of the intestinal Lumen.  “internal” fistula.  “external” fistula.  Sinus tracts
Slide 48-

 Colovesical internal fistula. 52-year- old woman with diffuse Crohn’s disease status post multiple prior small bowel resections resulting in short bowel syndrome.  This image from a single contrast barium retrograde rectal enema demonstrates a narrowed and irregular rectosigmoid colon, with a fistula communicating from the inferior aspect of the sigmoid colon to the bladder ( arrow )
Slide 49-

 Terminal ileal deep ulcers and abscess formation.  This 25-year-old woman with Crohn’s ileocolitis underwent ileocecal resection 4 years prior to this study.  The patient presented with a non-resolving right lower quadrant mass for over a year. Small bowel followthrough shows active infl ammation involving the distal ileum just proximal to the ileocolic anastomosis. There  are deep ulcers ( arrowheads ) with medial perforation into an abscess demonstrated by irregular collections of contrast material ( arrow )
Slide 50-

 Fistulogram. 20 mL of water-soluble iodinated contrast was injected through a percutaneous tube into a fistulous tract. It demonstrates ramifying fi stulae, communicating with the distal ileum ( arrows ) and the rectosigmoid ( arrowheads )
Slide 51-

ppt slide no 51 content not found
Slide 52-

APTHOUS ULCERS First sign of chron’s disease on barium
Slide 53-

APHTHOUS ULCER
Slide 54-

APHTHOUS ULCER
Slide 55-

Cobblestone appearance: due to deep fissuring ulcers around inflammed mucosa
Slide 56-

Fissuring ulceration in Crohn'sdisease - graphically called `raspberrythorn' ulcers.
Slide 57-

COBBLESTONE- LONGITUDNAL & CIRCUMFERENTIAL FISSURES AND ULCERS SEPARATE ISLANDS OF MUCOSA, GIVING IT AN APPEARANCE REMINISCENT OF COBBLESTONES.
Slide 58-

A SMALL BOWEL ENEMA SHOWING EXTENSIVE JEJUNAL DISEASE CHARACTERIZED BY LOSS OF DISTENSIBILITY, (THE CAPABILITY OF BEING STRETCHED OR DISTENDED), THICKENING OF THE SMALL-BOWEL WALL AND GROSS DISRUPTION OF THE CIRCULAR HAUSTRAL FOLD PATTERN, WHICH IS LARGELY REPLACED BY A MARKED COBBLESTONE EFFECT. CD OF THE JEJUNUM
Slide 59-

COBBLESTONE CROHN DISEASE. THIS IS A MAGNIFIED IMAGE FROM THE RIGHT ILIAC FOSSA PERFORMED AS PART OF A SMALL BOWEL FOLLOW THROUGH. IT SHOWS THE CLASSIC APPEARANCE OF CROHN DISEASE IN THE TERMINAL ILEUM – SO-CALLED ‘COBBLESTONING’. THIS IS CAUSED BY EXTENSIVE FISSURES AND ULCERATION IN BETWEEN AREAS OF INTACT BUT OEDEMATOUS MUCOSA, RESEMBLING COBBLESTONES (ARROWS).
Slide 60-

ROSE THORN THE DEEP, LINEAR ULCERS (ARROWS) THAT HAVE FILLED WITH BARIUM IN THIS STENOSED TERMINAL ILEUM ARE KNOWN AS ‘ROSE-THORN ULCERS’ AND ARE TYPICAL OF CROHN DISEASE.
Slide 61-

String sign: spasm/fibrosis of bowelwall
Slide 62-

ILEOILEAL FISTULA: long standing chron’s
Slide 63-

 spatial and temporal with good luminal distention
Slide 64-

CT features of active Crohn disease  mucosal hyperenhancement(most sensitive indicator of active Crohn disease )  wall thickening (thickness > 3 mm)  mural stratification with a prominent vasa recta (comb sign)  mesenteric fat stranding,  reactive lymphadenopathy  complications such as fistulas and abscesses
Slide 65-

ppt slide no 65 content not found
Slide 66-

stratification  mural stratification denotes the visualization of bowel wall layers at CT  At CT enterography, the edematous bowel wall has a trilaminar appearance, with enhanced outer serosal and inner mucosal layers and an interposed submucosal layer of lower attenuation
Slide 67-

Findings in inactive Crohn disease  submucosal fat deposition  pseudosacculation  surrounding fibrofatty proliferation  fibrotic strictures.
Slide 68-

 pseudosacculation of the antimesenteric border, Involvement of the mesenteric border of the affected bowel segment in the inflammatory process, with associated asymmetric fibrosis.  Fibrofatty proliferation in the surrounding mesentery is thought to play a role in sustaining the inflammatory process related to the production of tumor necrosis factor a .  bowel strictures occurring as a complication.  Submucosal fat deposition is commonly associated with longstanding disease
Slide 69-

Reversible vs irreversible stricture  Reversible strictures produced by active disease demonstrate  mucosal hyperenhancement,  mural stratification,  fat stranding,  engorgement of the vasa recta  lack of enhancement and loss of stratification might be seen in the presence of transmural fibrosis  Is It important to differentiate?
Slide 70-

ppt slide no 70 content not found
Slide 71-

 Submucosal fat deposition in longstanding Crohn disease. Axial CT enterographic section shows abnormally low attenuation of the bowel wall (arrow-heads), a finding consistent with submucosal fat deposition. Submucosal fat deposition in longstanding Crohn disease. Axial CT enterographic section shows abnormally low attenuation of the bowel wall (arrow-heads), a finding consistent with submucosal fat deposition.
Slide 72-

Recurrent Crohn disease after bowel resection.
Slide 73-

 Large bowel involvement in Crohn disease. Axial CT enterographic sections obtained in three different patients show luminal narrowing and dilatation in a segment of the ascending colon (arrow in a), a perianal abscess (arrow in b), rectosigmoid involvement (black arrowhead in c), and a comb sign (white arrowheads in c).
Slide 74-

 Capsule impaction in bowel stricture due to Crohn disease. Anteroposterior radiograph (a) and axial CT enterographic section (b) demonstrate the impaction of an endoscopic capsule (black arrow) within the lumen of a thick-walled diseased ileal segment (white arrow in b).
Slide 75-

 Fistula formation in Crohn disease. Coronal volume-rendered CT enterographic sections obtained in two patients depict ileo-ileal fistulas (arrowheads in a) and an ileocolonic fistula (arrow in b).
Slide 76-

 Abscess formation in Crohn disease. Axial (a) and coronal volume- rendered (b) CT enterographic sections show a large fluid collection (arrows) with attenuation similar to that of enteric contrast material. Lack of communication between the collection and the bowel, as well as the marked difference in caliber between the two, helps confirm an extraluminal location of the collection. Note the evidence of active Crohn disease (* in a) in the terminal ileum
Slide 77-

Fat halo sign in chron’s disease Transverse CTscan shows the central fatty submucosal layer of low attenuation (*) surrounded by higher-attenuation inner (long arrow) and outer(short arrow) layers grossly corresponding to the mucosa and muscularis propria and serosa of the descending colon, respectively.
Slide 78-

COMB SIGN:Hypervascular appearance of the mesentery in active Crohn's disease. Fibrofatty proliferation and perivascular inflammatory infiltration outline the distended intestinal arcades. This forms linear densities on the mesenteric side of the affected segments of small bowel, which give the appearance of the teeth of a comb.
Slide 79-

ppt slide no 79 content not found
Slide 80-

CECTimage, coronalsection, venous phase - enterocecal fistula with secondary traction of the cecum and right psoas muscleabscess
Slide 81-

Bowel distention  There are two techniques to acquire distension of the small bowel:  MR enterography: oral administration of contrast.  MR enteroclysis: administration of contrast via a nasojejunal tube.  We routinely perform MR enterography as it suffices in the large majority of patients while being less burdensome and more time efficient.
Slide 82-

Oral contrast  For oral contrast several options are available. Mannitol in water solution (2%), which provides good contrast between lumen and bowel wall on both T1 and T2 sequences and is well accepted by patients. There is one precaution: no colonoscopy with electrocoagulation should be performed directly after the MRI because of methane resulting from Mannitol breakdown.
Slide 83-

MRI sequences  Balanced FFE (axial and/or coronal) in breath-hold  T2 with fat sat (axial) in breath-hold  T1 pre- and post-contrast (axial/coronal) in breath-hold Optional sequences:  T2-FSE without fat sat for additional overview and comparison with T2 with fat sat.  Diffusion Imaging (DWI).  Balanced FFE cine-study for motility.
Slide 84-

MRI signs of Crohn’s disease.
Slide 85-

Bowel wall thickness  With adequate distension the normal bowel wall has a thickness of 1-3 mm.  A common categorization is 3-5 mm for mild thickening, 5- 7 mm for moderate thickening and > 7 mm for marked thickening of the bowel wall.  T1 weighted post-contrast images or non fatsat T2 weighted images (if available) are preferable for measurement of bowel wall thickness.
Slide 86-

 The image is a coronal post-contrast T1 weighted image showing disease activity in the transverse colon with marked wall thickening of more than 7 mm and deep ulceration (arrow).
Slide 87-

 Increased bowel wall thickness is one of the most common signs of inflammatory activity, but not specific for Crohn's disease.  Bowel wall thickness correlates well with the severity of the disease activity.  Measurements are best performed on the sequence with good luminal distension.  Black border artifacts on balanced FFE sequences can distort thickness measurements.
Slide 88-

 Balanced FFE image shows marked bowel wall thickening and luminal narrowing of the terminal ileum. Measurement on the balanced FFE sequence can be less accurate due to the black border artifact (arrows).dc
Slide 89-

Enhancement  Abnormal bowel wall enhancement after administration of gadolinium is the result of increased vascular permeability and angiogenesis.  It is seen both in active disease and fibrosis.  Enhancement can be graded by comparing to the precontrast images, to normal bowel loops and nearby vascular structures.  No abnormal enhancement Equivalent to normal bowel wall Minor increased enhancement More than normal bowel wall, but significantly less than nearby vascular structures  Moderate enhancement Somewhat less than nearby vascular structures  Marked enhancement Equal or more intense than nearby vascular structures
Slide 90-

 Thickened terminal ileum segment with marked enhancement on axial post-contrast T1W image with fatsat.
Slide 91-

 The latter two enhancement patterns can only be appreciated when the wall is thickened.  There is some discussion about the value of the enhancement pattern.
Slide 92-

Homogeneous enhancement  Strong homogeneous enhancement is seen in active inflammation.  The image shows a terminal ileum with a homogeneous enhancement pattern with moderate (green arrow) and marked (red arrow) enhancement on an axial post- contrast T1 image.
Slide 93-

Mucosal enhancement  This is seen as bowel wall thickening with increased enhancement of the mucosal layer relative to the outer layers.  The image is a post-contrast T1 image with a mucosal enhancement pattern in the terminal ileum (arrow).  There is relatively low enhancement of the middle and outer layers
Slide 94-

Layered enhancement pattern  This pattern suggests severe disease activity or longstanding chronic disease.  The three-layered appearance is caused by strong enhancement of the mucosa and the serosa with no enhancement of the middle layer, which is the submucosa and the muscular layer.  This middle layer can consist of fat, edema or fibrotic tissue.  This can be distinguished using a fat sat T2 sequence.
Slide 95-

 Layered enhancement pattern of the rectum with some surrounding fat stranding on an axial post-contrast T1 image (arrow). Continued inflammation with a homogeneous enhancement pattern can be seen in the sigmoid colon (green arrow). Also, a right- sided adnexal cyst is present with enhancing rim (arrowheads).
Slide 96-

T2 mural signal intensity  Increased mural signal intensity on fat-saturated T2 images indicates the presence of mural edema, suggesting active disease.  Presence of bowel wall thickening with a low mural T2 signal intensity is more suggestive of fibrotic disease.  The psoas muscle can be used as a reference when assessing mural T2 signal.  Fat suppression is routinely used to differentiate between mural fat depositions and mural edema. Fat depositions are the result of chronic bowel inflammation and therefore quite common in Crohn's disease.  However, its presence does not indicate active disease.  Perimural edema or fluid can be identified as well and is associated with active disease .
Slide 97-

T2 mural signal intensity can be graded as follows using a T2 sequence with fat sat:  No increase normal bowel wall  Minor increase bowel wall appears dark gray  Moderate increase bowel wall appears light gray  Marked increase bowel wall contains areas of white high signal approaching that of luminal content.
Slide 98-

 Actively inflamed terminal ileum with marked thickening and moderate mural signal intensity (mural edema) on an axial T2 with fat sat.
Slide 99-

 inflamed small bowel showing wall thickening and mild mural T2 signal (arrow) on an axial T2 with fat sat. Prestenotic dilatation can be seen proximally of the diseased segment.
Slide 100-

 Fat suppression is routinely used to differentiate between mural fat depositions and mural edema.  Fat depositions are a result of chronic bowel inflammation, but not typical of active disease.  These fat depositions can be diffuse but can also present as a layered pattern.  The CT equivalent for this pattern is the 'fat-halo sign'.
Slide 101-

 Wall thickening of the terminal ileum in a 67-year-old male with Crohn's disease since 11 years. Layered enhancement is seen on an axial post-contrast T1 image with fat sat (left). T2 with fat sat (middle) shows the same pattern with a middle layer of low intensity. T2 without fat sat shows an increased signal in the middle layer, suggesting fat depositions. Endoscopy showed only superficial disease
Slide 102-

Ulceration  Moderate to deep ulceration can be seen on T1 and T2 images, but small ulcerations can be difficult to distinguish from mucosal folds depending on the degree of luminal distension.  Ulcerations are active spots of inflammation and usually there is increased enhancement on the post-contrast T1 images.
Slide 103-

 Coronal post-contrast T1 and T2 fat sat images show multiple small ulcerations in the terminal ileum.
Slide 104-

Loss of haustration  When the colon is involved in Crohn's disease a decrease of haustral folds can be seen.  A complete loss of haustration results in a smooth surface.  This is also a common finding in ulcerative colitis and known as 'lead pipe' colon.  The coronal post-contrast T1 image shows loss of haustral folds throughout the colon in a patient with chronic Crohn's disease.
Slide 105-

Comb sign  Increased vascularity of the mesentery is seen in active inflammation.  The engorged vessels have a linear appearance, resembling the teeth of a hair comb (comb sign).
Slide 106-

Creeping fat  Creeping fat, also called fibrofatty proliferation or fat wrapping, are different names for hypertrophy of the subserosal fat.  It is a common finding in longstanding Crohn's disease.  The image shows creeping fat surrounding the descending colon. It isolates the colon from surrounding bowel loops.
Slide 107-

ppt slide no 107 content not found
Slide 108-

Skip lesions  Skip lesions and patchy inflammation are a typical finding in Crohn's disease, in contrast to the continuous inflammation, which is seen in ulcerative colitis.  Skip lesions refers to the interspersed inflammation "skipping" parts of the bowel, which are left unaffected (green arrows).
Slide 109-

 The coronal T1 post- contrast image (left) and the T2 image (right) show skip lesions in the terminal ileum. The affected lesions show increased enhancement with a layered pattern (yellow arrows), while another part is unaffected or skipped (green arrows).
Slide 110-

Stenosis  Stenosis can present as bowel wall thickening combined with lumen narrowing. The presence of a prestenotic dilatation increases the likelihood of a stenosis  Abnormal contrast enhancement of the affected bowel segment is usually present.  In the grading system, only severe stenosis is included as a complication, which is defined as a stenosis with prestenotic dilatation and a moderate-to- marked increase in mural T2 signal.
Slide 111-

 Coronal post-contrast T1 image with a stenosis at the ileocecal junction (left). No obvious pre- stenotic dilatation is seen. The stenosis was non-passable using endoscopy (right).
Slide 112-

Infiltrate  Infiltrate can be seen as creeping fat between bowel loops with replacement of the fat signal intensity and tethering and kinking of bowel loops.  Obstructive symptoms due to adhesions, inflammatory narrowing or fibrosis are common.  Fistulas and abscesses are often present. Due to the complex structure, the exact path of a fistula can be difficult to define.
Slide 113-

ppt slide no 113 content not found
Slide 114-

Fistula  Sinus tracts and fistulas are common complications in patients with Crohn's disease. Both show marked enhancement on T1 images after administration of gadolinium. A fistulous track can present with a layered 'tram track' configuration or as a linear enhancing structure.  It can be seen going from one bowel loop to another bowel loop, to another hollow organ or to the skin.
Slide 115-

ppt slide no 115 content not found
Slide 116-

ppt slide no 116 content not found
Slide 117-

Abscess  Abscesses are often seen in patients with severe active Crohn's disease.  Abscesses are characterized by rim enhancement on post-contrast T1 images and central high signal intensity on T2 images.  The abscess is frequently surrounded by fat stranding.
Slide 118-

ppt slide no 118 content not found
Slide 119-

ppt slide no 119 content not found
Slide 120-

ppt slide no 120 content not found
Slide 121-

ppt slide no 121 content not found
Slide 122-

ppt slide no 122 content not found
Slide 123-

ppt slide no 123 content not found
Slide 124-

ppt slide no 124 content not found
Slide 125-

ppt slide no 125 content not found
Slide 126-

Causes superficial ulceration of colon and rectum. It starts from rectum and retrogradely involves whole colon  continuously. In total colitis- back wash ileitis. More common in DR2 relatedgenes. More female predilection, age group 30-40 yrs. Clinical symtoms- diarrhoea, tenesmus, bleeding per rectum, passage ofmucus, crampy abdominal pain. ULCERATIVECOLITIS
Slide 127-

MILD DISEASE: fine granularity MODERATE: marked erythema, coarse granularity, contactbleeding and no ulceration. SEVERE:spontaneous bleeding,edematous and ulcerated Long standing cases epithelialregeneration- pseudopolyps, pre cancerous condition Eventually shortening and narrowing of colon FULMINANT DISEASE: toxic colitis/megacolon PATHOGENESIS
Slide 128-

Acute UC – descending colon has irregular outline. No fecal residue in colon S/O total colitis
Slide 129-

Mucosal inflammation-granular appearance to the surface of the bowel. Mucosal ulcers are undermined -button-shapedulcers Islands of mucosa remain giving it a pseudo-polyp appearance In chronic cases the bowel becomes featureless with loss of normal haustral markings, luminal narrowing and bowel shortening- lead pipe sign BARIUM ENEMA
Slide 130-

FINE MUCOSAL GRANULARITY- FIRSTSIGN NARROWING OFLUMEN
Slide 131-

COLLAR BUTTON ULCERS
Slide 132-

ppt slide no 132 content not found
Slide 133-

LEAD PIPECOLON
Slide 134-

Back wash ileitis : patulous ICvalve and dilated granular terminal ileum
Slide 135-

COLLAR BUTTON ULCERS- CLASSICALLY SEEN IN THE COLON ASSOCIATED WITH ACTIVE UC. THE COLLAR BUTTON APPEARANCE IS FORMED BY MUCOSAL ULCERATION WITH ASSOCIATED UNDERMINING OF THE EDGE BY LATERAL SUBMUCOSAL EXTENSION.
Slide 136-

LEAD PIPE COLON DOUBLE CONTRAST BARIUM ENEMA IN LONG STANDING ULCERATIVE COLITIS CASE SHOWS CLASSIC ‘LEAD PIPE’ SIGN. THE IMAGE DEMONSTRATES DESCENDING COLON AND SIGMOID COLON TO BE FEATURELESS WITH LACK OF HAUSTRA AND NARROWING.
Slide 137-

PSEUDOPOLYPS THIS DOUBLE CONTRAST BARIUM ENEMA REVEALS AN IRREGULAR MUCOSA AND NUMEROUS SMALL FILLED NODULES OR POLYPOIDS THROUGHOUT THE ENTIRE COLON REPRESENTATIVE OF INFLAMMATORY PSEUDOPOLYPS IN LONG STANDING ULCERATIVE COLITIS. ALSO VISIBLE ARE SMALL WORM LIKE STRUCTURES THAT ARE SMALL GROUPS OF RESIDUAL MUCOSA CALLED FILIFORM POLYPS.
Slide 138-

CTFINDINGS Inflammatory pseudopolyps Inflamed and thickened bowel - target appearance, due concentric rings of varying attenuation- mural stratification In chronic cases, submucosal fat deposition is seen particularly in the rectum fathalo sign Extramural deposition of fat, leads to thickening of the perirectal fat, widening of the presacral space Marked muscularis mucosa hypertrophy-lead pipe sign.
Slide 139-

INFLAMMATORY PSEUDOPOLYPS
Slide 140-

ppt slide no 140 content not found
Slide 141-

ppt slide no 141 content not found
Slide 142-

Wall Thickening- median wall thickeness of colon ranges from 4.7 to 9.8 mm, more severe the disease more thicken the wall Increased Enhancement- enhancement of themucosa with no or less enhancement of the submucosa Loss of haustralmarkings MRI
Slide 143-

Mri image reveals thickening of colon with loss of haustral markings
Slide 144-

 thanks