ABSTRACT
INTRODUCTION: Transient hepatic attenuation differences (THAD) are areas of high parenchymal enhancement observed during the hepatic arterial phase on computed tomography (CT). THAD in the left lobe of the liver can lead to surgical complications. METHODS: A retrospective study was conducted on patients who underwent multislice computed tomography (MSCT) examination of the upper abdomen to understand the morphology, distribution, and causes of THAD and their correlation with hepatic artery variation. RESULTS: Among 179 cases, 65 and 114 belonged to diseased and normal groups, respectively. THAD as observed in MSCT demonstrated various shapes: lobe/segment (127 cases; 70.9%), irregular sheet (31; 17.3%), strip shape (9; 5.02%), arc/semicircle (7; 3.9%), and segment + flaky (5; 2.79%). THAD were found to be caused by liver tumor (32.3%), hepatic inflammatory lesions (6.15%), biliary tract diseases (13.8%), perihepatic disease compression (9.23%), portal vein obstructive disease (1.53%), and lesion in left hepatic lobe with hepatic artery variation (29.2%). THAD exhibited variation in distribution in the left lobe of the liver. Among 114 cases, THAD in 18 (15.7%) cases were observed in the S2 segment, six (5.26%) in the S3 segment, and 90 (78.9%) in multiple segments of the liver, that is, 50 cases in S2 and S3 segments and 40 cases in S2, S3, and S4 segments. The hepatic artery of 179 cases was of various types based on Hiatt classification: 57 cases of Hiatt I (31%), 65 cases of Hiatt II (37%), 11 cases of Hiatt III (6%), 17 cases of Hiatt IV (10%), 7 cases of Hiatt V (4%), 12 cases of large left hepatic artery (7%), 6 cases of right hepatic artery originating from the celiac trunk (3%), and 4 cases (2%) of superior mesenteric artery originating from the celiac trunk. CONCLUSION: THAD can occur as a result of specific pathological causes and hence should be considered as a diagnostic sign in liver pathologies.
Subject(s)
Hepatic Artery/cytology , Hepatic Artery/diagnostic imaging , Liver Diseases/diagnostic imaging , Liver Diseases/diagnosis , Liver Diseases/physiopathology , Multidetector Computed Tomography/methods , Adult , Aged , Aged, 80 and over , China , Female , Humans , Male , Middle Aged , Retrospective Studies , Young AdultABSTRACT
In 2001, the European Association for the Study of the Liver (EASL) endorsed the possibility of achieving a non-invasive diagnosis of Hepatocellular Carcinoma (HCC) for the first time. Since then, various refinements of the criteria and techniques capable of achieving this diagnosis and the role of plasma and tissue oncomarkers have been reported in the literature and have been accepted to different extents in various geographical areas. Such tools can also potentially imply prognostic significance. The present article critically discusses some of the most relevant and debated challenges which have emerged in this field, including the role of contrast-enhanced ultrasound, and of hepatocyte-specific magnetic resonance contrast agents, the pitfall of transient hepatic attenuation differences, the reliability of biopsy and the status of biomarkers.
Subject(s)
Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Ultrasonography , Algorithms , Biopsy , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/diagnostic imaging , Contrast Media/administration & dosage , Critical Pathways , Diagnosis, Differential , Humans , Liver Neoplasms/blood , Liver Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/standards , Practice Guidelines as Topic , Predictive Value of Tests , Prognosis , Reproducibility of Results , Tomography, X-Ray Computed/standards , Tumor Burden , Ultrasonography/standardsABSTRACT
OBJECTIVE: To describe the appearance of transient hepatic attenuation differences (THADs) of extrahepatic origin. MATERIALS AND METHODS: Five cases of THADs produced by compression of the extrahepatic portal vein at its confluence with the splenic vein were identified prospectively over a four-month period. Two additional cases of peripheral THADs resulting from main portal vein thrombosis were identified from retrospective review of a departmental database. RESULTS: Streamlining of portal venous flow resulted primarily in left lobar THADs when the portal vein is compressed at its confluence with the splenic vein. THADs were seen in the periphery of the liver in the two cases of main portal vein thrombosis. CONCLUSION: Lobar and/or peripheral THADs can be produced by compromise of splenic and extrahepatic portal venous flow. Radiologists should be familiar with the "central pseudotumor" created by the peripheral THAD that can result from portal vein thrombosis.
ABSTRACT
Objective To study CT and MRI appearance of transient hepatic attenuation difference (THAI)) .to reveal the cause of THAD),and to avoid false positive and misdiagnosis.Methods 10 cases appearing THAD in CT and 5 cases appearing THAI) in MRI were reviewed and all were processed with plain scan and dy- namic contrast with CT or MRI.Results 7 cases appeared transienl hypertransfusion of CT,4 cases appeared tran- sient hypertransfusion of MRI;3 cases appeared transient Hypoperfusion of CT,1 case appeared transient hypoperfu- sion of MRI.Conclusion The appearance of THAD in CT and MRI,was related to the quick-scan with CT and MRI only sufficient comprehension of the characteristics of blood supply in normal physiology and pathology of liver, combined with plain scan,could make correct decision possible in the final diagnosis when it occurred regional perfu- sion difference in liver.
