What is abdominal compartment syndrome (ACS), and what are its CT and MRI features?
ACS is a life-threatening condition characterized by increased intraabdominal pressure (>20 mm Hg) with dysfunction of at least one thoracoabdominal organ. (Normal intraabdominal pressure is ≈5 mm Hg.) Potential etiologies of ACS include trauma, abdominal surgery, pancreatitis, sepsis, massive fluid resuscitation, and abdominal malignancy. Treatment is generally with decompressive laparotomy along with supportive therapy.
On CT and MRI, a rounded configuration of the abdomen is typically seen, with an anteroposterior : transverse abdominal diameter ratio of >0.8 (“round belly” sign). Other imaging findings may include ascites or hemoperitoneum; presence of retroperitoneal disease; flattening of the inferior vena cava or renal veins; bowel wall thickening and hyperenhancement; heterogeneous hepatic enhancement; and elevation of the diaphragm.
