GOOD AFTERNOON!

PERITONEAL CAVITY

Peritoneal cavity

fluid filled GAP b/n the wall of the abdomen and the organs contained w/in the abdomen

Contains small amount of fluid that serves as a lubricant & has anti- inflammatory properties

Males:

completely closed

Females:

communicates with exterior of body via uterine tubes, uterus and vagina

PERITONEUM

➲ Serosal membrane➲ Single layer of flat

mesothelial cells supported by submesothelial CT

➲ 2 layersa.visceralb.parietal

VISCERAL/ PARIETAL PERITONEUM

➲ Inner layer of the membrane which wraps around the internal organs

➲ Outer layer attached to the abdominal wall

INTRAPERITONEAL ORGANS• Nearly totally covered by

visceral peritoneum• Projects into the peritoneal

cavity• Attached to body wall by

mesenteries and ligaments• LIVER, SPLEEN, STOMACH,

1ST PART OF DUODENUM, JEJUNUM, ILEUM, TRANSVERSE & SIGMOID COLON, SUPERIOR RECTUM

RETROPERITONEAL ORGANSA. PRIMARY: KIDNEYS

-develop & remain beneath the parietal peritoneum

B. SECONDARY: ADRENAL GLANDS, PANCREAS, 2ND-

4TH PART OF DUODENUM, ASC & DESC COLON-developed w/ short mesentery-fusion fascia

MESENTERIES

TRUE MESENTERIES: connect to the posterior peritoneal wall

➲ Small Bowel Mesentery➲ Transverse Mesocolon➲ Sigmoid Mesentery or

Mesosigmoid

SPECIALIZED MESENTERIES: do not connect to the posterior peritoneal wall

Greater Omentum Lesser Omentum Mesoappendix

OMENTUM

GREATER Double layer of peritoneum Hangs fr the greater curvature

of the stomach & descends infront of the abdominal viscera separating bowel fr the ant abdl wall

Encloses fat and a few BV Serves as s fertile ground for

implantation of peritoneal metastases and assists in loculation of inflammatory processes of the peritoneal cavity

LESSER Suspends the lesser curve of

the stomach & the duodenal bulb from the inferior surface of the liver

Separates the gastrohepatic recess of the left subphrenic space fr the lesser sac

Tansmits the coronary vein and contains LN

OMENTUM

GREATER OMENTUM

Gastrocolic LigamentGastrosplenic LigamentGastrophrenic

Ligament

LESSER OMENTUMGastrohepatic LigamentHepatoduodenal

Ligament

LIGAMENTA.LIVER

1. Falciform - liver-ant abdl wall2. Gastrohepatic - lesser curvature of the stomach-liver3. Hepatoduodenal - liver-1st part of duodenum

B. SPLEEN1. Gastrosplenic-stomach to hilum of spleen2. Splenorenal (lienorenal)-spleen-left kidney

C. STOMACH1. Gastrophrenic-stomach-

inf diaphragmatic surface2. Gastroplenic-stomach-

hilum of spleen3. Gastrocolic-stomach as

the greater omentum- transverse colon

D.PHRENICOCOLIC LIGAMENT/ SUSTENTACULUM LIENIS-left hepatic flexure-

transverse colon-diaphragm-supports the spleen

GASTROHEPATIC LIGAMENT ON UTZ

SUBDIVISIONS OF THE PERITONEAL CAVITY

GREATER SAC Main compartment

Extends from the diaphragm into the pelvis

A. Supramesocolic CompartmentB. Inframescolic Compartment

LESSER SAC/ OMENTAL BURSA Smaller

Lies behind the stomach

A. Superior RecessB. Inferior Recess

Foramen of winslow

3-cm potential opening anterior to the IVC and posterior to the hepatoduodenal ligament

communication between the lesser sac and the greater peritoneal cavity

Bowel may herniate through it

SUBPHRENIC SPACE

RIGHT:

ANT SUBHEPATIC

POST SUBHEPATIC/ MORISON POUCH/ RIGHT HEPATORENAL FOSSA

LEFT/PERISPLENIC:

LEFT SUBHEPATIC SPACE / GASTROHEPATIC RECESS

Space affected by disease of the duodenal bulb, lesser curvature of the stomach, GB, left lobe of the liver

PERITONEAL CIRCULATION

Watershed Regions:1. Ileocolic region2. Root of the Sigmoid Mesentery3. Pouch of Douglas

Clinical correlation

ASCITES

at least 500 mL to be present.Plain film findings of ascites

include: diffusely increased density of the

abdomen poor definition of the the soft

tissue shadows, such as the psoas muscles, liver and spleen

medial displacement of bowel and solid viscera (away from properitoneal fat stripe)

bulging of the flanks increased separation of small

bowel loops

ASCITES

UltrasoundMay detect smaller volumes

especially if its adjacent diaphragm or the anterior margin of the liver 3.

Assessment of fluid type:Simple ascites = anechoicExudative, haemorrhagic or

neoplastic ascites contains floating debris

Septations suggest inflammatory or neoplastic cause

ASCITES

Transudative ascites density (-10 to +10HU).

Exudative ascites density > 15 HU.

Haemoperitoneum density is higher still (~ 45HU).

PNEUMOPERITONEUM

1. Rigler’s or double wall sign visualization of serosal and mucosal surface of one or more dilated gaseous small bowel loops ( seen as thin white line ), but many of the times it would be misleading

2. Football sign or air dome sign Lot of free air in the parietal peritoneal cavity.

3. Cupola sign Free air under right diaphragm near midline in supine position

4. Falciform ligament sign Visualisation of falciform ligment due to air around it

PNEUMOPERITONEUM

5. Morrison’s pouch sign Air in hepato-renal pouch due to pneumoperitoneum

6. Telltale triangle or Triangular air sign

7. Right upper quadrant sign air below or around part ( sub or perihepatic ) of the liver surface

8. Umbilical inverted V sign9. Scrotal air sign ( in

children )

PNEUMOPERITONEUM

PNEUMOPERITONEUM

free (extraluminal) air between the Liver and the inner surface of the anterior abdominal wall on either side of the Falciform ligament.

SPLENIC TRAUMA

a subcapsular hematoma with a splenic laceration extending from the capsule to the hilum with an intraparenchymal hematoma (blue arrow).  Within the intraparenchymal and subcapsular hematomas are areas of hyperdensity that represent active extravasation (red arrow).

HERNIA THROUGH THE FORAMEN OF WINSLOW

Abscess formation on ultrasound and CT. (a) Ultrasound shows a heterogeneous fluid collection with dirty shadowing (arrows)

consistent with intraluminal gas, a thickened wall and multiple septations in a 13-year-old boy. (b) CT demonstrates a rim

enhancing, hypodense, and well-defined bilobed fluid collection in a 15-year-old boy.

SUB-PHRENIC ABSCESSStwo large abscesses (arrows) situated below the right side of the diaphragm. (CT image shows a cross-section through the

abdomen, looking from below). The abscesses have well-defined margins of connective tissue with semi-dense pus in the cavity. These abscesses are most likely secondary to gall

bladder perforation.

  Tumor seeding in the peritoneal cavity after RF ablation of a metastatic liver nodule. (a) Follow-up CT scan obtained 1 day after

RF ablation shows the ablated area with peritumoral hyperemia (arrow) in the left lateral segment of the liver. (b) Follow-up CT scan

obtained 6 months later shows multiple extrahepatic and intraperitoneal tumor nodules (arrows) just below the site of

ablation.

Sonographic features. Hepatocellular carcinoma in 59-year-old man. Unenhanced gray-scale sonogram shows peripheral halo sign

(arrow).

Spontaneous rupture of a hepatomaThe CT scan of the abdomen and pelvis at 2 levels reveals a heterogenous 4-cm mass within the dome of the right lobe of the liver (blue arrow), with active bleeding. High-density material around the liver and under the right

hemidiaphragm (yellow arrows) that extends down along the right pericolic gutter into the pelvis is consistent with blood based on

Hounsfield unit measurement. The liver has a shrunken, nodular contour suggestive of cirrhosis.

Incisional Hernia. A hernia through a surgical wound created during cholecystectomy is well visualized in a patient with ascites

(a). The ascites clearly defines the layer of parietal peritoneum (arrow) lining the peritoneal cavity. Omentum containing fluid

between its layers herniates (arrowheads) into the abdominal wall. Ascites fluid (f) has also dissected into the hernia sac. The size of

the hernia defect is measured by a cursor (+). Omentum is differentiated from bowel by absence of peristalsis and lack of

continuity with bowel in the peritoneal cavity.