Increased hepatic arterial blood flow after decreased portal supply to the liver parenchyma owing to intrahepatic portosystemic venous shunt: angiographic demonstration using helical CT

This study was conducted to investigate the haemodynamics of the liver parenchyma in the presence of intrahepatic portosystemic venous shunt. 3 patients with intrahepatic portosystemic venous shunts and 24 patients with normal intrahepatic haemodynamics underwent both CT arterial portography and CT during hepatic arteriography. Angiographic findings with helical CT were compared, and CT attenuated values were measured in both groups. The liver parenchyma on CT arterial portography had lower attenuation than on CT during hepatic arteriography in all patients with intrahepatic portosystemic venous shunts. Overall average CT attenuation was 92.2 +/- 7.7 Hounsfield units (HU) on CT arterial portography and 149.9 +/- 8.5 HU after CT during hepatic arteriography, with the opposite findings in all patients without intrahepatic portosystemic venous shunt: CT attenuation 142.0 +/- 25.7 HU on CT arterial portography and 100.7 +/- 16.4 HU after CT during hepatic arteriography. In conclusion, the portal venous supply to the liver parenchyma decreased due to intrahepatic portosystemic venous shunts, with a compensatory increase in hepatic arterial blood supply.     

Preoperative evaluation of hepatocellular carcinoma: combined use of CT with arterial portography and hepatic arteriography

OBJECTIVE: This study was undertaken to determine the usefulness of combined CT during arterial portography and CT hepatic arteriography in the preoperative evaluation of patients with known or suspected hepatocellular carcinoma and to describe the findings on CT during arterial portography and CT hepatic arteriography by which hepatocellular carcinomas may be differentiated from pseudolesions. SUBJECTS AND METHODS: This study included 137 patients who underwent combined CT during arterial portography and CT hepatic arteriography for the preoperative evaluation of known or suspected hepatocellular carcinoma. The images were prospectively evaluated to identify focal hepatic lesions and their differential diagnoses (hepatocellular carcinoma versus pseudolesion). We assessed the diagnostic accuracy of our prospective interpretation by comparing the interpretations with the results of histopathology or follow-up imaging. We also retrospectively analyzed imaging features seen on CT during arterial portography and CT hepatic arteriography-the size, shape, and location of the lesion within the liver; attenuation of the lesion; and opacification of the peripheral portal vein branches on CT hepatic arteriography. RESULTS: One hundred and forty-nine hepatocellular carcinomas (75 lesions confirmed at histopathology and 74 lesions on follow-up imaging) were found in 120 patients, and 104 pseudolesions (15 lesions confirmed at histopathology and 89 lesions on follow-up imaging) were found in 91 patients. The sensitivity of our prospective interpretations was 98.7%, and the specificity of our prospective interpretations was 90.4%. Our positive and negative predictive values were 93.6% and 97.9%, respectively. We found that hepatocellular carcinomas were larger, more frequently nodular, and more likely to be located intraparenchymally than were the pseudolesions (p < 0.01). Opacification of the peripheral portal vein branches on CT hepatic arteriography was detected in 36 pseudolesions (34.6%) but in none of the hepatocellular carcinomas (p < 0.01). CONCLUSION: Combining CT during arterial portography and CT hepatic arteriography is useful for the preoperative evaluation of patients with known or suspected hepatocellular carcinoma. Familiarity with the imaging features of hepatocellular carcinomas and pseudolesions can help in the accurate differentiation of hepatocellular carcinomas from pseudolesions.     

Effects of prostaglandin E(1) injection through the superior mesenteric artery on the hemodynamics of hepatocellular carcinoma.

OBJECTIVE: The purpose of our study was to assess the effects of portal blood flow on contrast enhancement in hepatocellular carcinoma lesions on CT hepatic arteriography. SUBJECTS AND METHODS: We examined 43 tumors in 39 patients who simultaneously underwent CT during arterial portography and CT hepatic arteriography for examination of liver tumors and then CT hepatic arteriography with prostaglandin E(1) injection via the superior mesenteric artery. All lesions pathologically confirmed to be hepatocellular carcinomas exhibited portal perfusion defects on CT during arterial portography. Changes in CT attenuation, size, and shape of liver tumors visualized on CT hepatic arteriography after intraarterial injection of prostaglandin E(1) were studied. In addition, changes in CT attenuation of the liver parenchyma surrounding the tumor were measured. RESULTS: The CT attenuation increased significantly after injection of prostaglandin E(1) in 91% (39/43) of the lesions (mean increase from 176.4 to 206.6 H; p = 0.0006, paired t test). The size and shape of the enhanced area generally did not change. The CT attenuation of the liver parenchyma surrounding each liver tumor significantly decreased in 58% (25/43) of the hepatocellular carcinoma lesions (mean decrease from 94.8 to 92.0 H; p = 0.0166, paired t test) and lesion conspicuity increased in 91% (39/43) of the tumors. CONCLUSION: Lesion conspicuity on CT hepatic arteriography between hepatocellular carcinoma and the surrounding liver parenchyma increased because of greater portal perfusion after the prostaglandin E(1) injection.     

Sequential hemodynamic change in hepatocellular carcinoma and dysplastic nodules: CT angiography and pathologic correlation

OBJECTIVE: The purpose of this study was to clarify the hemodynamic changes associated with hepatocarcinogenesis using CT angiography. MATERIALS AND METHODS: Eighty-six hepatocellular lesions were confirmed at pathology in 49 patients who underwent CT with both hepatic arteriography and arterioportography. These images were compared with lesion-to-liver vascular ratios of cumulative arteries, preexisting hepatic arteries, and portal veins in resected specimens. Lesions were classified in five groups according to intranodular hemodynamics determined by CT hepatic arteriography and CT during arterioportography: group 1, isoattenuating on both procedures; group 2, hypoattenuating on CT hepatic arteriography and isoattenuating on CT during arterioportography; group 3, hypoattenuating on both procedures; group 4, isoattenuating on CT hepatic arteriography and hypoattenuating on CT during arterioportography; and group 5, hyperattenuating on CT hepatic arteriography and hypoattenuating on CT during arterioportography. RESULTS: Among 86 lesions, we identified seven low-grade dysplastic nodules, eight high-grade dysplastic nodules, 14 well-differentiated hepatocellular carcinomas, 45 moderately differentiated hepatocellular carcinomas, and 12 poorly differentiated hepatocellular carcinomas. The lesions were classified as group 1 (n = 5), group 2 (n = 13), group 3 (n = 6), group 4 (n = 2), or group 5 (n = 60). Intranodular hemodynamics was significantly correlated with pathologic grading (p < 0.001). For correlations between combinations of the groups and pathologic gradings, the order "groups 1-2-3-4-5" was the most significant (p < 0.001). CONCLUSION: During hepatocarcinogenesis, most hepatocellular nodules show deterioration of arterial blood flow before loss of portal blood flow. Vascular imaging of hepatic nodules may predict malignant abnormality via the early loss of hepatic arterial flow seen before portal flow changes.     

CT arteriography of hepatic tumors]

The liver has dual blood supply from the portal vein and hepatic artery. Computed tomographic findings of hepatic neoplasms are greatly influenced by hepatic blood flow, and abnormal portal and hepatic arterial blood flow needs to be examined separately by CT arteriography (CTA) and CT during arterial portography (CTAP). Both CTA and CTAP have advantages over conventional CT in that they can provide greater contrast enhancement of hepatic tumors by injecting contrast material directly into the hepatic or superior mesenteric arteries. The methods of CTA and CTAP are described. CTA and CTAP were useful in the detection of small hepatic lesions, evaluation of changes in hepatic parenchymal blood flow, and evaluation of portal flow in hepatocellular carcinoma, which contribute to the classification of HCC. In conclusion, CTA and CTAP were indispensable in selecting a therapeutic approach.     

Dynamic CT of hepatic abscesses: significance of transient segmental enhancement

OBJECTIVE: The purpose of this study was to evaluate dynamic CT findings of hepatic abscesses, especially segmental hepatic enhancement, and to clarify the cause. MATERIALS AND METHODS: Twenty-four abscesses in eight patients were examined by early (30 sec) and late phase (90 sec) dynamic CT. Patients underwent abscess drainage (n = 1), hepatic resection (n = 2), or antibiotic therapy (n = 5). CT during arterial portography and CT during hepatic arteriography were performed in one patient. We retrospectively observed the frequency and changes of segmental hepatic enhancement on dynamic CT and determined its cause using radiologic and pathologic correlation. RESULTS: Sixteen abscesses (67%) showed transient segmental hepatic enhancement and three abscesses showed only segmental hepatic enhancement in the early phase. Four abscesses in one patient who underwent CT during arterial portography and CT during hepatic arteriography showed a segmental perfusion defect on CT during arterial portography and segmental enhancement on CT during hepatic arteriography. On follow-up dynamic CT performed 10-17 days after the initial CT, segmental hepatic enhancement surrounding hepatic abscesses decreased or disappeared in all abscesses. Pathologic examination of two patients showed marked inflammatory cell infiltration with stenosis of portal venules within the portal tracts surrounding hepatic abscesses without definite inflammation in the liver parenchyma. CONCLUSION: Segmental hepatic enhancement on dynamic CT is frequently associated with hepatic abscesses and may be caused by decreased portal flow resulting from inflammation of the portal tracts.     

Transcatheter CT Arterial Portography and CT Hepatic Arteriography for Liver Tumor Visualization during Percutaneous Ablation

PurposeTo evaluate the feasibility of combining transcatheter computed tomography (CT) arterial portography or transcatheter CT hepatic arteriography with percutaneous liver ablation for optimized and repeated tumor exposure.Materials and MethodsStudy participants were 20 patients (13 men and 7 women; mean age, 59.4 y; range, 40–76 y) with unresectable liver-only malignancies—14 with colorectal liver metastases (29 lesions), 5 with hepatocellular carcinoma (7 lesions), and 1 with intrahepatic cholangiocarcinoma (2 lesions)—that were obscure on nonenhanced CT. A catheter was placed within the superior mesenteric artery (CT arterial portography) or in the hepatic artery (CT hepatic arteriography). CT arterial portography or CT hepatic arteriography was repeatedly performed after injecting 30–60 mL 1:2 diluted contrast material to plan, guide, and evaluate ablation. The operator confidence levels and the liver-to-lesion attenuation differences were assessed as well as needle-to-target mismatch distance, technical success, and technique effectiveness after 3 months.ResultsTechnical success rate was 100%; there were no major complications. Compared with conventional unenhanced CT, operator confidence increased significantly for CT arterial portography or CT hepatic arteriography cases (P < .001). The liver-to-lesion attenuation differences between unenhanced CT, contrast-enhanced CT, and CT arterial portography or CT hepatic arteriography were statistically significant (mean attenuation difference, 5 HU vs 28 HU vs 70 HU; P < .001). Mean needle-to-target mismatch distance was 2.4 mm ± 1.2 (range, 0–12.0 mm). Primary technique effectiveness at 3 months was 87% (33 of 38 lesions).ConclusionsIn patients with technically unresectable liver-only malignancies, single-session CT arterial portography–guided or CT hepatic arteriography–guided percutaneous tumor ablation enables repeated contrast-enhanced imaging and real-time contrast-enhanced CT fluoroscopy and improves lesion conspicuity.     

The aetiology of non-tumorous enhancement in the hepatic hilum shown on CT hepatic arteriography

The causes of non-tumorous abnormalities in the hepatic hilum seen on CT hepatic arteriography were investigated. 13 patients with non-tumorous defects of portal perfusion in the hepatic hilum on CT arterial portography underwent both CT hepatic arteriography from the common hepatic artery and CT obtained during proper hepatic arteriography. The findings of non-tumorous portal defects on these two angiographic studies using helical CT were compared. In the 13 patients, 14 non-tumorous defects of portal perfusion in the hepatic hilum on CT arterial portography were detected as enhanced areas in 10 regions (dorsum of segment IV, 7/10; dorsum of the lateral segment, 3/4) on CT hepatic arteriography via the common hepatic artery, but none were enhanced on CT obtained during proper hepatic arteriography. In conclusion, the main cause of non-tumorous enhancement in the hepatic hilum seen on CT hepatic arteriography is non-portal direct inflow via the parabiliary venous system.     

Preoperative detection of hepatocellular carcinoma: ferumoxides-enhanced mr imaging versus combined helical CT during arterial portography and CT hepatic arteriography

OBJECTIVE: The purpose of this study was to compare ferumoxides-enhanced MR imaging with combined helical CT during arterial portography and CT hepatic arteriography for preoperative detection of hepatocellular carcinomas. SUBJECTS AND METHODS: Twenty patients with 30 hepatocellular carcinomas underwent ferumoxides-enhanced MR imaging and combined helical CT during arterial portography and CT hepatic arteriography. The diagnosis was established by pathologic examination after surgical resection in 18 patients and by biopsy in two. The MR protocol included fast spin-echo with two echo times, T2(*)-weighted fast multiplanar gradient-recalled acquisition in the steady state, proton density-weighted fast multiplanar spoiled gradient-recalled echo, and T1-weighted fast multiplanar spoiled gradient-recalled echo images. The MR images of all sequences and the paired CT during arterial portography and CT hepatic arteriography images were independently evaluated by three radiologists on a segment-by-segment basis. Diagnostic accuracy was assessed with receiver operating characteristic analysis. RESULTS: The accuracies (A(z) values) of ferumoxides-enhanced MR imaging and combined CT during arterial portography and CT hepatic arteriography for all observers were 0.964 and 0.948, respectively. The mean sensitivities of MR imaging and CT were 93% and 91%, respectively. The differences were not statistically significant. The mean specificity of MR imaging (99%) was significantly higher than that of combined CT during arterial portography and CT hepatic arteriography (94%). CONCLUSION: Ferumoxides-enhanced MR imaging can be used successfully in place of combined CT during arterial portography and CT hepatic arteriography for the preoperative evaluation of patients with hepatocellular carcinomas.     

Hepatic arterioportal shunts not directly related to hepatocellular carcinoma: findings on CT during hepatic arteriography, CT arterial portography and dual phase spiral CT

AIM: To evaluate findings of arterioportal shunts not directly related to hepatocellular carcinoma (HCC) which were seen within third-order portal branches on computed tomography (CT) during hepatic arteriography (CTHA), arterial portography (CTAP), and dual phase spiral CT.MATERIALS AND METHODS: At CTHA in 112 patients, we examined third-order portal vein branches to find arterioportal shunts not directly related to HCC. Six cases were found. We evaluated the findings of these shunts on CTHA and investigated whether CTAP (n = 6) and dual phase spiral CT (n = 5) showed perfusion defects in the corresponding areas on arterioportal shunts. RESULTS: Five of six cases showed abrupt visualization of portal branches without visualization of the proximal portion of CTHA. Five of six cases showed no perfusion defect on CTAP and no hyperattenuating area on CTHA. Four of five cases showed no hyperattenuating area on hepatic arterial phase spiral CT. CONCLUSION: Arterioportal shunts not directly related to HCC and occuring within third-order portal branches mainly showed abrupt visualization of portal branches on CTHA. These occurred frequently without perfusion defects on CTAP and without a hyperattenuating area on CTHA and hepatic arterial phase spiral CT.Park, C. M. (2000). Clinical Radiology55, 465-470.     

Revealing hepatic metastases from colorectal cancer: value of combined helical CT during arterial portography and CT hepatic arteriography with a unified CT and angiography system

OBJECTIVE: The purpose of our study was to evaluate the use of combined helical CT during arterial portography and CT hepatic arteriography in the preoperative assessment of hepatic metastases from colorectal cancer using a unified CT and angiography system. MATERIALS AND METHODS: Fifty-four patients with hepatic metastases from colorectal cancer preoperatively underwent combined CT during arterial portography and CT hepatic arteriography using the unified CT and angiography system. Three radiologists independently and retrospectively reviewed the images of CT during arterial portography alone, CT hepatic arteriography alone, and combined CT during arterial portography and CT hepatic arteriography. Image review was conducted on a segment-by-segment basis; a total of 432 hepatic segments with (n = 103) 118 metastatic tumors ranging in size from 2 to 160 mm (mean, 25.8 mm) and without (n = 329) tumor were reviewed. RESULTS: Relative sensitivity of combined CT during arterial portography and CT hepatic arteriography (87%) was higher than that of CT during arterial portography alone (80%, p < 0.0005) and CT hepatic arteriography alone (83%, p < 0.005). Relative specificity of CT hepatic arteriography alone (95%, p < 0.0005) and combined CT during arterial portography and CT hepatic arteriography (96%, p < 0.0001) was higher than that of CT during arterial portography alone (91%). Diagnostic accuracy, determined by a receiver operating characteristic curve analysis, was greater with combined CT during arterial portography and CT hepatic arteriography than with CT during arterial portography alone (p < 0.05) or CT hepatic arteriography alone (p < 0.01). CONCLUSION: Using a unified CT and angiography system, we found that combined CT during arterial portography and CT hepatic arteriography significantly raised the detectability of hepatic metastases from colorectal cancer.     

Pseudolesions of the liver possibly caused by focal rib compression: analysis based on hemodynamic change

OBJECTIVE: The purpose of this study is to show and analyze the CT appearance of pseudolesions of the liver caused by rib compression and to discuss the possible mechanism on the basis of findings of incremental dynamic CT, CT during arterial portography, and CT hepatic arteriography. CONCLUSION: Focal compression of the liver caused by curved ribs can cause transient focal diminishment of portal venous perfusion without significantly altering hepatic arterial perfusion. Such diminishment may be observed as low-density areas on the early phase of incremental dynamic CT.     

中晚期肝癌动脉早期MSCT血管造影

目的 :探讨多层螺旋CT肝脏动脉早期扫描CT血管造影 (MSCTA)在中晚期肝癌的临床应用价值。方法 :63例临床确诊的中晚期肝癌病例 ,用TriggerBolus对比剂示踪软件行自动触发全肝动脉早、晚期 (一次屏气完成 )和门脉期扫描 ,动脉早期图像数据经后处理获得肝脏CT血管造影图像。分析肝脏及癌肿血供系统MSCTA表现 ,以及静脉癌栓、动静脉瘘的MSCTA表现。结果 :动脉早期扫描MSCTA能完整显示中晚期肝癌肝脏及癌肿供血动脉起源、形态、数目 ,显示动静脉瘘征象优于标准肝脏双期扫描。结论 :动脉早期扫描MSCTA在中晚期肝癌具有良好的临床应用前景 ,可作为中晚期肝癌治疗前进行综合评估的影像学检查方法     

CT during hepatic arteriography and portography: an illustrative review.

The combination of computed tomography (CT) during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) has been used for evaluation of hepatic neoplasms before partial hepatic resection. Focal hepatic lesions that can be demonstrated with CTAP and CTHA include regenerative nodules, dysplastic nodules, dysplastic nodules with malignant foci, hepatocellular carcinoma, cholangiocarcinoma, hemangioma, and metastases. CTAP is considered the most sensitive modality for detection of small hepatic lesions, particularly small hepatic tumors such as hepatocellular carcinoma and metastatic tumors. CTHA can demonstrate not only hypervascular tumors but also hypovascular tumors and can help differentiate malignant from benign lesions. However, various types of nontumorous hemodynamic changes are frequently encountered at CTAP or CTHA and appear as focal lesions that mimic true hepatic lesions. Such hemodynamic changes include several types of arterioportal shunts, liver cirrhosis, Budd-Chiari syndrome, inflammatory changes, pseudolesions due to an aberrant blood supply, and laminar flow in the portal vein. Familiarity with the CTAP and CTHA appearances of various hepatic lesions and nontumorous hemodynamic changes allows the radiologist to improve the diagnostic accuracy.     

Adenomatous hyperplasia with unusual imaging findings at combined helical CT hepatic arteriography and CT during arterial portography

We examined a patient with a hepatocellular carcinoma and multiple adenomatous hyperplasias in the cirrhotic liver. Helical CT hepatic arteriography (CTA) showed the adenomatous hyperplasias as areas of discrete hypoattenuation, and the combined CT during arterial portography (CTAP) showed corresponding areas of subtle hyperattenuation. Such imaging findings at combined CTA and CTAP were seen in only one patient in a series of more than 80 patients in whom we performed angiographically-assisted CT. We demonstrate these unusual imaging findings of adenomatous hyperplasia in the report.     

Value of intraarterial prostaglandin E(1) injection during CT hepatic arteriography.

OBJECTIVE: The purpose of our investigation was to determine if injection of prostaglandin E(1) during CT hepatic arteriography could help physicians to distinguish tumors from nonportal venous flow-related pseudolesions in the region of the gallbladder fossa. SUBJECTS AND METHODS: In 34 patients who underwent CT during arterial portography to detect liver tumors, CT hepatic arteriography was performed before and after prostaglandin E(1) injection via the superior mesenteric artery. Between each study, an interval of 10 minutes was set. On CT hepatic arteriogram obtained 15 to 20 sec after prostaglandin E(1) injection, we distinguished changes in the size and shape of pseudolesions in the liver around the gallbladder as well as those of 42 tumorous lesions. In addition, we measured the change in CT attenuation of pseudolesions. RESULTS: The size of the enhanced area of pseudolesions visible on CT hepatic arteriography decreased in 69% (25/36) of the pseudolesions after intraarterial prostaglandin E(1) injection, with the mean diameter diminishing from 14.1 mm to 8.8 mm. Notably, in 11 pseudolesions, the enhanced area disappeared. In 86% (31/36), the CT attenuation decreased with the mean attenuation, diminishing from 211.3 H to 163.8 H. However, the size and shape of the enhanced area of tumorous lesions did not change. CONCLUSION: The hemodynamic features of pseudolesions on angiographically assisted helical CT scans caused by cholecystic venous inflow are easily influenced by increased portal venous flow. Consequently, pseudolesions around the gallbladder usually can be distinguished from tumorous lesions by adding prostaglandin E(1) injection via the superior mesenteric artery during CT hepatic arteriography.     

Opacification of the intrahepatic portal veins during CT hepatic arteriography

PURPOSE: The purpose of this study was to ascertain the cause of opacification of the portal veins during CT hepatic arteriography (CTHA). METHOD: A total of 155 consecutive patients with hepatocellular carcinoma were evaluated with CTHA as preoperative staging. The opacification of the portal veins during CTHA was categorized as opacification of the main portal vein, right or left branches of the main portal vein (generalized), and segmental or subsegmental portal veins (localized). Hepatic angiography was compared and possible causes were evaluated. RESULTS: One hundred eight (70%) of 155 patients showed intrahepatic portal vein opacification at CTHA: generalized in 60 patients (39%) and localized in 48 patients (31%). Intrahepatic causes were arterioportal shunts due to hepatocellular carcinoma in 20 (19% of 108 patients), previous liver biopsy in 9 (8%), and portal vein thrombosis in 4 (4%). Extrahepatic cause was counted in 57 cases (53%) and was due to inflow of contrast material via nonmesenteric portal circulation through the gastric antrum, duodenum, and/or pancreas. CONCLUSION: Intrahepatic portal veins are frequently opacified during CTHA, and the causes were arterioportal shunts through hepatocellular carcinoma, postbiopsy shunt, portal vein thrombosis, and inflow of contrast material via the nonmesenteric portal circulation.     

Portal flow into the liver through veins at the site of biliary-enteric anastomosis

The aim of this study was to establish the role played by jejunal veins in hepatopetal flow after biliary-enteric anastomosis and to evaluate the helical CT features of hepatopetal flow through the anastomosis. We retrospectively analyzed helical CT images of the liver in 31 patients with biliary-enteric anastomosis who underwent hepatic angiography with (n=13) or without (n=18) CT arterial portography within 2 weeks of the CT examination during the last 4 years. Arterial portography showed hepatopetal flow through small vessels located (communicating veins) between the elevated jejunal veins and the intrahepatic portal branches in two (9%) of 22 patients with a normal portal system. Helical CT showed focal parenchymal enhancement around the anastomosis in these two patients. All nine patients with extrahepatic portal vein occlusion (100%) had hepatopetal flow through the anastomosis, and four of the nine had decreased portal flow. CT revealed small communicating veins in two of these four patients. In five patients with normal portal perfusion despite extrahepatic portal vein occlusion, CT detected dilated communicating veins and elevated jejunal veins. The presence of communicating veins and/or focal parenchymal enhancement around the anastomosis indicates hepatopetal flow through the elevated jejunal veins.     

Regenerative nodules in liver cirrhosis: findings at CT during arterial portography and CT hepatic arteriography with histopathologic correlation

PURPOSE: To determine the appearance of regenerative nodules in patients with liver cirrhosis at computed tomography (CT) during arterial portography (CTAP) and CT hepatic arteriography (CTHA). MATERIALS AND METHODS: CTAP and CTHA of the liver were performed in 28 consecutive patients with hepatocellular carcinoma (HCC) who were scheduled to undergo partial resection of the liver. Helical CTAP was performed after contrast material injection into the superior mesenteric artery followed by helical CTHA after contrast material injection into the hepatic artery. CT scans were analyzed for the presence of identifiable nodules and their size; results were correlated with gross and microscopic findings. RESULTS: Resected livers showed cirrhosis in 20 patients, chronic hepatitis in four, and normal liver in four. Among the 20 patients with cirrhosis, regenerative nodules were demonstrated as enhancing 3-10 mm nodules surrounded by lower attenuation fibrous septa 0.8-1.5 mm thick at CTAP in seven patients and nonenhancing nodules of the same size surrounded by enhancing fibrous septa at CTHA in 15 patients. The degree of fibrosis determined the conspicuity of nodules. CONCLUSION: Regenerative nodules in cirrhotic liver are visualized as enhancing nodules surrounded by lower attenuation thin septa at CTAP and nonenhancing nodules surrounded by enhancing fibrous septa at CTHA. CTHA is more sensitive than CTAP in depicting regenerative nodules (P < .005).     

Correlation of a defect of portal perfusion in the dorsal part of segment IV of the liver on CT arterial portography with inflow of the aberrant pancreaticoduodenal vein

The correlation between an aberrant pancreaticoduodenal vein and a portal perfusion defect in the dorsal part of segment IV as demonstrated on CT arterial portography (CTAP) was investigated. 14 patients with non-tumorous defects of portal perfusion in the dorsal part of segment IV of the liver parenchyma, shown on CTAP underwent CT during pancreaticoduodenal arteriography. The defect on CTAP was shown as an enhanced area resulting from non-portal venous inflow in eight (57%) of 14 patients on CT during pancreaticoduodenal arteriography. In conclusion, the non-portal venous supply via an aberrant pancreaticoduodenal vein occasionally causes a defect of portal perfusion in the dorsal part of segment IV on CT arterial portography.