ACUTE ABDOMEN

Inflammation Versus ObstructionOrgan Lesion

Stomach Gastric UlcerDuodenal Ulcer

Biliary Tract

Acute chol’y +/-choledocholithiasis

Pancreas Acute, recurrent, or chronic pancreatitis

Small Intestine

Crohn’s diseaseMeckel’s diverticulum

Large Intestine

AppendicitisDiverticulitis

Location Lesion

Small Bowel Obstruction

AdhesionsBulgesCancerCrohn’s diseaseGallstone ileusIntussusceptionVolvulus

Large BowelObstruction

MalignancyVolvulus: cecal or sigmoidDiverticulitis

Causes by Systems

System Disease System DiseaseCardiac Myocardial infarction

Acute pericarditisEndocrine Diabetic ketoacidosis

Addisonian crisis

Pulmonary PneumoniaPulmonary infarctionPE

Metabolic Acute porphyriaMediterranean feverHyperlipidemia

GI Acute pancreatitisGastroenteritisAcute hepatitis

Musculo- skeletal

Rectus muscle hematoma

GU Pyelonephritis CNSPNS

Tabes dorsalis (syph)Nerve root compression

Vascular Aortic dissection Heme Sickle cell crisis

Diagnosis

PNEUMOPERITONEUM

CAUSES:Bowel perforationInsufflation of gas (CO2 or

air) during laparoscopy.

Abdominal X-rayAlthough the erect chest X-ray is a much

more sensitive investigation for pneumoperitoneum, there are several signs that may be useful in detecting free gas on an abdominal X-ray.

Rigler's/double wall signRigler's sign (also known as the double wall

sign) is the appearance of lucency (gas) on both sides of the bowel wall.

Football sign - example2 radiographs were required to completely cover the abdomen in this large patientA large volume of free gas has risen to the front of the peritoneal cavity resulting in a large round black area - 'football sign'The double wall sign (Rigler's) is also visible (arrowhead)

The cupola sign is seen on a supine chest or abdominal radiograph .It refers to dependant air that rises within the abdominal cavity of the supine patient to accumulate underneath the central tendon of the diaphragm in the midline. The superior border is well defined, but the inferior margin is not. Hence, it appears like an inverted cup, hence the name.

cupola sign

Decubitus Abdomen Sign

There is evidence of free air between the abdominal wall and the liver (white arrow). There is also evidence of free fluid in the peritoneum (black arrow).

 Contrast-enhanced axial CT scan through the liver shows a

collection of air anterior to the liver. Also note the air surrounding the gallbladder.

SMALL BOWEL OBSTRUCTION

CausesAdhesionsBulgesCancerCrohn’s diseaseGallstone ileusIntussusceptionVolvulus

Fluid Filled Small Bowel Air Filled Small Bowel

String-of-Pearls Sign: Erect

ILEUSHypomotility of the gastrointestinal tract in the

absence of mechanical bowel obstruction.

• Appearance are similar to those of Mechanical obstruction

• There are multiple loops of gas filled bowels centrally over abdomen

• This patient had prolonged non colicky abdominal pain following a cesarean section

Sentinel LoopA localized loop of small bowel is dilated with acute pancreatitis

LARGE BOWEL OBSTRUCTION

CAUSES

Colo-rectal carcinoma Diverticular strictures Hernias Volvulus

Adhesions do not commonly cause large bowel obstruction.

Large bowel obstructionHere the colon is dilated down to the level of the distal descending colon. There is the impression of soft tissue density at the level of obstruction (X). No gas is seen within the sigmoid colon.Obstruction is not absolute in this patient as a small volume of gas has reached the rectum (arrow).An obstructing colon carcinoma was confirmed on CT and at surgery.

VOLVULUS

Twisting of the bowel The two commonest types of

bowel twisting are sigmoid volvulus and caecal volvulus.

SIGMOID Volvulus

The sigmoid colon is more prone to twisting than other segments of the large bowel because it is 'mobile' on its own mesentery, which arises from a fixed point in the left iliac fossa (LIF).

CAECAL VOLVULUS

Caecum is most frequently a retroperitoneal structure, and therefore not susceptible to twisting. However, in up to 20% of individuals there is congenital incomplete peritoneal covering of the caecum.

The massively dilated caecum no longer lies in the right iliac fossa (RIF).

ACUTE APPENDICITIS

Causes Stones, food,

mucus adhesions Tumors lymphoid

hyperplasia

Findings on plain film Normal Focal ileus Appendicolith Mass Free air is very rare

Normal appendix; Barium enema radiographic examination.

Normal appendix; Computed tomography (CT) scan

a normal appendix. A and B, longitudinal (A) and transverse (B) sonogram, showing the appendix (arrowheads) with a diameter less than the 6 mm cut-off point, surrounded by normal no inflamed fat.

Longitudinal and transverse sonogram show an enlarged appendix (arrows) surrounded by hyper echoic inflamed fat (arrowheads).

ACUTE PANCREATITISCauses

GallstonesAlcohol abuse, usually chronicERCP-inducedTrauma, more often penetratingDrug-inducedInfectious, especially post-viral in

childrenVasculitisIdiopathic

Normal Pancreas

Acute Pancreatitis

The pancreas is enlarged (blue arrow) with indistinct and shaggy margins.There is peripancreatic fluid (red arrow) and extensive peripancreatic infiltration of thesurrounding fat (black arrow). 

ACUTE CHOLECYSTITIS

Transverse ultrasound image (with color flow) thickening of the gallbladder wall (two-head arrow), distended gallbladder.

 Coronal CT image performed ,reveals gas (arrow) in the gallbladder lumen, marked thickening of the gallbladder wall (double-head arrow), distention of gallbladder, enhancement of gallbladder wall (arrowheads). Conglomerate mass in the gallbladder wall represents sludge. Findings are consistent with emphysematous cholecystitis.