Intrahepatic and portal venous gas detected by ultrasonography.

During a 3-year period, sonographic evidence of portal venous gas (PVG) was found in 11 patients. Of these, 10 patients were examined for clinically suspected necrotizing enterocolitis (NEC). In the 11th patient, suffering from nephroblastoma, PVG was detected by routine sonography. Radiographic examination, performed in nine of 11 patients did not show any PVG. Intestinal pneumatosis was radiographically identifiable in only four of these children, whereas eight of 11 patients with sonographically detectable PVG also had sonographic evidence of intramural gas. Follow-up examinations in five patients showed cessation of PVG soon after onset of adequate therapy, indicating that ultrasonography is also a reliable method for monitoring NEC. Sonographic evidence of PVG, however, may be limited to the time before onset of therapy.