Abstract: Objective To investigate the clinical and imaging features of hepatic portal vein pneumatosis (HPVG). Methods The clinical and imaging data of 23 patients with HPVG found by CT examination were retrospectively analyzed, and they were divided into mild, moderate and severe according to the distribution range of HPVG gas. Results The main causes of 23 patients with HPVG were intestinal ischemia / necrosis in 3 cases (13.0%), intestinal obstruction in 3 cases (13.0%), sepsis in 3 cases (13.0%), acute gastrointestinal bleeding in 2 cases (8.7%), acute severe pancreatitis in 2 cases (8.7%), diving decompression disease in 9 cases (39.1%), hydrogen peroxide poisoning in 1 case (4.3%). CT examination showed that the white blood cell count increased within 24 hours before / after HPVG (>10×10⁹/L). Among the 23 patients with HPVG, there were 3 cases (13.0%) of mild pneumatosis, 3 cases (13.0%) of moderate pneumatosis and 17 cases (73.9%) of severe pneumatosis. Severe HPVG was found in 1 patient with an interval of about 4 hours before and after CT examination. Another patient with severe HPVG was reexamined by CT about 4 hours later and showed that HPVG was basically absorbed. Eighteen patients (78.3%) survived and 5 patients (21.7%) died. All the 5 dead patients had disturbance of consciousness on admission, all of which were severe HPVG. Conclusion CT examination can show the range of gas distribution in patients with HPVG and assist in the diagnosis of etiology. Severe HPVG may be a sensitive sign of fatal results, but not a specific sign. Early diagnosis and intervention can significantly improve the prognosis of patients and reduce mortality.

Key words: Portal vein gas, Ischemic bowel disease, CT angiography, Image features