Kobkun Muangsomboon MD. Diagnostic Radiology

Department of Radiology Faculty of Medicine, Siriraj Hospital

Interpretation of plain film abdomen

Objective

•  techniques : what and when •  interpretation : how •  limitation of plain film abdomen

Strategies

•  detection •  description •  differential diagnosis •  decision

Radiologic abdominal Survey.

- PA or AP erect chest radiograpy -  Supine radiograph of the abdomen

including the pelvic floor -  Upright radiograph of the abdomen -  Lateral decubitus radiograph -  Prone radiograph -  Lateral radiograph of the abdomen (cross

table )

-  organ identification : tissue fat interface, organ enlargement

-  abdominal calcifications -  bowel gas pattern : dilatation, distribution ,

air - fluid level -  extraluminal air : free air / abnormal gas

collection -  soft tissue mass

Interpretation

Organ Identification

Organ  identification

Abnormal Calcifications

chronic pancreatitis

staghorn stone

stippled calcifications

calcified myoma uteri

tooth-like calcification

dermoid tumor

retroperitoneal teratoma

retroperitoneal teratoma

Limitation

•  non-opaque stone •  obscured small stone

What is it?

Bowel Gas Pattern

Bowel characteristic Small bowel

•  circumferential fold •  diameter 3-5 cm •  many number of loops •  central distribution of

loops •  no feces content

Large bowel •  haustra •  diameter > 5 cm •  few number of loops •  Peripheral distribution

of loops •  feces content

Intestinal obstruction

•  distended bowel loops -  disproportion of bowel loops diameter gas -

fluid levels at different height in the same loop

-  string of pearl appearance

SBO small bowel obstruction: stepladder pattern

SBO small bowel obstruction

closed loops obstruction mid gut volvulus

coffee bean sign: sigmoid volvulus

Ileus

•  temporary arrest of intestinal peristalsis •  symptoms: nausea, vomiting

abdominal discomfort •  causes:

intra-abdominal infection metabolic disturbance drugs

Ileus

Localized ileus

•  acute pancreatitis •  acute appendicitis single loop dilatation sentinel loop dilatation

Goal of imagings

•  to differentiate obstruction or ileus •  to determined level of obstruction •  to determine cause of obstruction •  to look for complication •  to plan management

Limitation

acute colonic pseudo-obstruction

fluid filled bowel loops

Extraluminal air

-  Pneumoperitoneum : ulcer perforation neoplasm perforation iatrogenic perforation diverticulitis

Extraluminal air

-  radiolucency at right upper abdomen -  air beneath dome of diaphragm (upright

position) / subdiaphragmatic free air -  cupola sign -  double wall sign (Rigler sign) -  triangular sign -  falciform ligament sign

Pneumoperitoneum

Pneumoperitoneum

Pneumoperitoneum

Pneumoperitoneum

-  intestinal wall gas: pneumatosis intestinalis ischemic bowel disease obstruction collagen vascular disease

-  gas in portal vein: ischemic bowel disease -  aerobilia : post sphincterotomy, infection, fistula -  intraabdominal abscess with gas formation

Extraluminal air

Pneumatosis intestinalis

small bowel obstruction: dilated small bowel loops, string of pearls and aerobilia

Gallstone Ileus

•  plain film : Rigler triad 1. partial / complete small bowel obstruction 86% 2. aerobilia 69% 3. ectopic calcified gallstone (common >2.5 cm

in diameter) 25%

aerobilia

Air in Portal Vein air in portal vein

CXR-upright Lt.lateral decubitus

subdiaphragmatic abscess

Limitation

Limitation

•  sensitivity / specificity •  timing / late manifestation •  difficult to determine cause of abnormality

Pseudopneumo peritoneum

-  Interposition of bowel -  Distended bowel loops of stomach -  Subphrenic abscess -  Subpulmonic pneumothorax -  Intramural gas

Abnormal soft tissue mass

Limitation •  mass characterization •  extension

Abnormal density foreign body

coin

lipiodol staining from TACE

TEST

small bowel obstruction

colonic obstruction

Conclusion

•  advantage •  limitation •  clinical information •  further investigation / follow up film

Reference

1.  Baker SR. The abdominal plain what will be its role in the future? Radiol clin North Am 1993; 31: 1335-44

2.  Eisenberg RL. Gastrointestinal Radiology. 3rd ed. Philadelphia: Lippicott-Raven, 1996

3.  Maniatis V, Chryssikopoulos H, Roussakis A, Kalamara C, Kavadias S, Papadopoulos A, et al. Perforation of the alimentary tract: evaluation with computed tomography, Abdom Imaging. 2000;25: 373 – 79

4.  Marincek B. Nontraumatic abdominal emergencies: acute abdominal pain: diagnostic strategies. Eur Radiol. 2002;12 : 2136-50

5.  Taourel P, Kessler N, Lesnik A, Blayac PM, Morcos L, Bruel LM. Nontraumatic abdominal emergencies: imaging of acute intestinal obstruction. Eur Radiol. 2002; 12 : 2151-60

Thank you for attention