بسم هللا الرحمن الرحيم

Dr. Ahmed Abdallah Eisawy

MBBS M.Sc MD

THE ROLE OF COMPUTERIZED

TOMOGRAPHY(CT)

IN INVESTIGATION OF

COLONIC DIVERTICULUM DISEASE

Evaluation of colonic diverticulum and

its sequence like

(peridivcrticulitis,abscesses,

stricture,fistula) is piont of our study

• In recent years, CT scanning has been

assuming an increasing role. Most now

consider it the procedure of choice

• both for its ability to image

transmural/extraluminal disease and

adjacent structures, as well as its

therapeutic potential in the drainage of

abscesses

NORMAL APPEARANCES OF

COLON BY COMPUTERIZED

TOMOGRAPHY(CT)

CT CRITERIA OF COLONIC

WALL • Measurement of colonic wall at different levels in normal

individuals have shown thickness between 0.9 and 2.6 mm with a standard deviation of 0.4 mm.

• A slight increase in the wall thickness of collapsed colonic segments is often seen.

• It is safe to assume that when the colon is distended its wall thickness does not exceed 3 mm, while on a collapsed colon it is not greater than 5 mm .

• The pericolic fat, connective tissue, and mesentric attachments appear as homogenous structures, having a fat density and a few thin enhancing vascular channels (Mori et al., 1992).

caecum

• The caecum and

ascending colon can

be seen anterior to

the muscles of the

posterior abdominal

wall on the right side.

• Its average axial

length is about 6 cm.

hepatic flexure

• The hepatic flexure

can be seen lateral to

the second part of the

duodenum

ASCENDING COLON

• About 15 cm. long and is narrower than the caecum.

Relations:

• Anteriorly: Coils of Small Intestine, Greater Omentum, and Anterior abdominal wall.

• Posteriorly: Iliacus, Iliac crest, Quadratus Lumborum, Lower pole of right kidney

Iliohypogastric and Ilioinguinal nerves cross behind it. Snell, 1995)

splenic flexure

• The splenic flexure is

seen behind the

greater curvature of

the stomach and the

anterior splenic tip.

The Transverse Colon

• About 50 cm

• T axial view shows the transverse colon extending from the liver on the right, to the splenic tip on the left side crossing the duodenum and head of pancreas (Charnsangavej et af., 1993)

descending colon

• The descending colon

is seen on the

muscles of the

posterior abdominal

wall on the left side

• Is less than 30 cm.

long

SIGMIOD COLON

• Relations:

• Anteriorly: urinary

bladder in male; uterus

and vagina in female.

• Posteriorly: Rectum,

Sacrum and lower coils of

terminal part of ileum

.(Snell. 1995)

• It is usually less than 4.5 cm long

rectum

• The rectum measures approximately 12 to 15 cm. in length

• lower third is related to urinary bladder, vas deferens, seminal vesicles, and prostate

• The lower third is related to posterior surface of vagina.

• PATHOLOGY

AND IMAGING OF

COLONIC DIVERTICULUM

EPIDEMIOLOGY OF DIVERTICULAR DISEASE

• GEOGRAPHIC DISTRIBUTION

Epidemiologic studies indicate that

diverticular disease is essentially unheard

in Non-developed areas of Africa and

Asia(Joseph T.ferrrucci) Diverticulosis coli

is one of the most common disease seen

in western civilization than in Africa and

Asia

AGING EFFECTS

• 1%: before 30th year

• 3%:before 40"'year

• 5% from 40lh - 50th year

• 10%:in the 50-70 year

• >30%; older than 70 years

• Both sexes are affected with equal frequency.

• DISTRIBUTION OF DIVERTICULA IN THE COLON

• Most divcrticula are in

the sigmoid colon

(80-90%)

ETIOLOGICAL FACTORS

• DIETARY FACTORS

high dietary fiber content of native diets results in

large volume semisolid stools,

• LIFESTYLE

Defecation using standard western society toilets

generates much greater intracolonic pressures

than seen in the third world

• 3) COLLAGEN ALTERATION IN AN ANIMAL

MODEL OF COLONIC DIVERTICULOSIS

. PATHOGENESIS OF

DIVERTlCULAR DISEASE • 1)MUSCULAR CHANGES

Muscular Weakening. (simple massed diverticulitis)

Muscular Hypertrophy. (spastic colon diverticulosis).

• 2)1NCREASE IN INTRALUMINAL

PRESSURE.

• 3)LOCAL WEAKNESS

Diverticula arise at locations in the colonic wall where large branches of the vasa recta penetrate the muscle layer

PATHOLOGICAL

TERMS,SEOUANCE • DIVERTICULAR DISEASE

Diverticular disease is characterized by clinical symptoms, where by surgical specimens show the characteristic abnormal musculature usually with diverticula, which, however, can be absent or inflamed .

• DIVERTICULOSIS:

Multiple occurrence of pseudodiverticula or (rarely) true diverticula

• DIVERTICULITIS:

Acute or chronic inflammation of one or more diverticula, intermittent with remission and reactivation; mirco or macroperforations with peridiverticulitis.

SEQUENCE AND STAGING

• STAGE OF DIVERTICULITIS AND PERIDIVERTICULITIS are often classified in stages : (Neffand VanSonnenberg, 1989).

• STAGE 0

The inflammation remains beneath the serosa. Cellulitis of the sigmoid wall. Colonic wall phlegmon is also possible.

• STAGE I

Small abscess or phlegmon up to 3 cm in diamter, limited to the mesentery (pericolic abscess).Inflammatory infiltration of the pericolic fat.

• STAGE II

Perforation of pericolic abscess through the mesentery, limited by structures such as the greater omentum, small intestines, colon or fallopian tubes. Abscesses with a diameter of 5-15 cm.

• STAGE III Spread of abscess to the minor pelvis, to other regions of the abdominal

cavity, or to the retroperitonium.

• STAGE IV

Through a large perforation of a diverticulum, faeces enters the abdominal cavity acute peritonitis and sepsis

COMPLICATIONS OF

DIVERTICULAR DISEASE

• 1-DIVERTICULAR BLEEDING

• 2-FISTULA

• 3-OBSTRUCTION

• 4-INTRA-ABDOMINAl ABSCESS

• 5-PERFORATION AND PERITONITIS

C.T. CRITERIA OF DIVERTICULITIS

• MURAL SIGNS

1) Thickening of the bowel wall

(concentric,homogenous)

2)stricture formation

3) intramural air loculi

4) Diverticula

• EXTRAMURAL SIGNS

1) exophytic fat permeation

2) Pericolic inflammation

3) Pericolic abscesses

4) fistula

• CT scanning shows: CT scan demonstrate right-sided diverticulitis in association with obvious pericolic inflammatory changes consistent with acute diverticulitis (right sided diverticulitis) exophytic fat permeation stricture, wall thickening (concentric, heterogenous))

• Provisional diagnosis: right side diverticulitis

• CT scanning shows::

• diffuse inflammation of the

wall of the sigmoid colon

with no extraserosal fluid

• (sigmiod diverticulitis

stricture,wall thickening

(concentric,heterogenous)

exophytic fat permeation)

• Provisional diagnosis:

acute sigmioid diverticulitis

• CT scanning shows: CT. scan shows multiple air-filled sigmoid diverticulitis.a focal region of pericolic inflammatory reaction is seen adjacent to the anterior wall of the sigmoid colon (arrow).

• CT. findings are consistent with early perforation of a single diverticulum at this site mild sigmiod diverticulitis ,perforation, stricture,wall thickening (concentric heterogenous)exophytic fat permeation

• Provisional diagnosis: mild diverticulitis with perforation

• CT scan shows pericolic inflammation predominantly involving The medial all of the cecum as well as severeal small right-sided diverticula

• Provisional diagnosis:. cecal diverticulitis

• CT scanning shows: • moderate wall thickening in the

sigmoid colon (S) with adjacent inflammatory changes and stranding of the pericolic fat. Focal wall thickening is seen in the left posterior part of the bladder adjacent to the inflamed sigmoid(arrow)

• A moderate amount of air is also present in the bladder, a finding compatible with a colovesical fistula.

• Small collections of retained barium are identified within diverticula (colovesical fistula stricture,wall thickening

(concentric,heterogenous) exophytic fat permeation sigmoid diverticulitis)

• CT scanning shows:. Transverse contrast-enhanced CT scans in a case with pneumaturia and prior diverticulitis show air (arrowhead) in the bladder and the site of fistulous communication (arrow) between sigmoid colon and bladder. Note diverticulosis of the sigmoid colon (colovesical fistula, stricture, wall thickening, concentric, heterogenous)

• Provisional diagnosis: Colovesical fistula

• CT scanning shows: large pericolic abscess due to diverticulitis.a debris and air filled abscess(arrow) has a thick,contrast enhancing wall large pericolic abscess, stricture, wall thickening, concentric, heterogenous exophytic fat permeation

• Provisional diagnosis: sigmoid diverticulitis with abscess

• CT scanning shows: Peridiverticular Abscess in a. The sigmoid colon in this CT scan has a thickened wall (S). A small fluid collection (arrow) indicates an intramural abscess extending to a contained extraluminal perforation and an organized inflammatory reaction posteriorly. Multiple diverticula are present acute sigmoid diverticulitis (intramural abscess)stricture,wall thickening ,concentric,heterogenous exophytic fat permeation

• CT scanning shows: extensive diverticulosis of the sigmoid colon there is hypertrophy of the central muscularis propria,which often accompanies severe colonic diverticulosis ,stricture wall thickening, concentric, heterogenous

• Provisional diagnosis: sigmiod diverticulosis

• CT scanning shows: • (A) show asymmetric inflammatory wall

thickening diverticula, fat stranding, and fascial thickening Note contained perforation with formation of phlegmon and extraluminal air.No free intraperitoneal extravasation of colonic contrast material is seen

• (B) Axial CT scans show asymmetric inflammatory wall thickening superimposed on muscular wall hypertrophy diverticula, fat stranding, and fascial thickening Note contained perforation with formation of phlegmon and extraluminal air No free intraperitoneal extravasation of colonic contrast material is seen. acute sigmiod diverticulitis,stricture wall thickening (concentric,heterogenous) exophytic fat permeation, perforation

• Provisional diagnosis: . acute diverticulitis of sigmoid colon

•On sonography, inflamed diverticula appear as bright echogenic foci

with acoustic shadowing or a ring-down artifact within or beyond the

thickened gut wall.

56-year-old man with acute

sigmoid diverticulitis.

Transverse gray-scale

image through left lower

quadrant shows wall

thickening of sigmoid colon

(arrowheads) with

associated diverticulum

(calipers). Adjacent

mesenteric and omental fat

(F) is abnormally echogenic

and attenuating, obscuring

deeper structures.