CT During Arterial Portography Research Articles

Prognostic Significance of Concurrent Hypovascular and Hypervascular Nodules in Patients with Hepatocellular Carcinoma.

BackgroundHypovascular nodules often occur together with hypervascular hepatocellular carcinoma (HCC). However, it remains controversial whether hypovascular nodules associated with hypervascular HCC have any prognostic value. This study evaluated the prognostic impact of hypovascular nodules co-existing with hypervascular HCC as diagnosed by computed tomography during arterial portography (CTAP) and computed tomography during hepatic arteriography (CTHA), which can sensitively capture the dynamic changes in blood flow through the portal vein and hepatic artery in patients with early stage HCC.MethodsA total of 152 patients with hypervascular HCC (≤ 30 mm, ≤ 3 nodules), who underwent initial local ablation, were analyzed retrospectively. All patients received CTAP and CTHA prior to treatment. Overall survival (OS) was compared among group A (hypervascular HCC only, 107 patients) and group B (hypovascular nodules and hypervascular HCC, 45 patients).ResultsAmong all hypovascular nodules, 81% (46 of 57) developed hypervascularization within the follow-up period. The 1- and 2-year hypervascularization rates were 17% and 51%, respectively. OS was significantly longer for group A than for group B (P < 0.001). A Cox proportional-hazards model identified the presence of hypovascular nodules concurrent with hypervascular HCC as an independent poor prognostic factor.ConclusionThe prognosis of hypervascular HCC patients with hypovascular nodules detected during CTAP and CTHA is poor. Clinical HCC categories seem to be dissimilar between patients with and without hypovascular nodules.

Genistein Produces Hepatoprotection through Modulating EGFR Expression and Phosphorylation in Experimental Fibrosis

Objectives: We observed the time-course changes of blood flow in non-hypervascular hepatocellular nodules that showed hypointensity in the hepatobiliary phase on Gd-EOB-DTPA-enhanced magnetic resonance imaging (EOB-MRI), and evaluated the relationship between hypervascular change and the status of blood supply in the nodules. Methods: The study included 69 hepatocellular nodules in 33 patients demonstrating hypointensity in the hepatobiliary phase on EOB-MRI and showing non-hypervascular features on CT during hepatic arteriography (CTHA) performed during the same period. Results: In relation to blood flow on CTHA/ CT during arterial portography (CTAP), the cumulative rate of hypervascular change at 52 weeks was 0.0% for iso/iso, 29.7% for hypo/iso, 61.5% for iso/hypo, and 55.0% for hypo/hypo. Multivariate analysis using COX proportional hazards regression showed that CTAP findings (hypodensity) and CTHA findings (hypo-density) were significant variables for hypervascular change. Conclusions: In cases of non-hypervascular hepatocellular tumors, nodules with decreased arterial or portal blood flow that show hypointensity in the hepatobiliary phase on EOB-MRI are likely to develop into typical hepatocellular carcinoma in a shorter time.

Change in Imaging Findings on Angiography-Assisted CT During Balloon-Occluded Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma.

To evaluate changes in imaging findings on CT during hepatic arteriography (CTHA) and CT during arterial portography (CTAP) by balloon occlusion of the treated artery and their relationship with iodized oil accumulation in the tumor during balloon-occluded transcatheter arterial chemoembolization (B-TACE). Both B-TACE and angiography-assisted CT were performed for 27 hepatocellular carcinomas. Tumor enhancement on selective CTHA with/without balloon occlusion and iodized oil accumulation after B-TACE were evaluated. Tumorous portal perfusion defect size on CTAP was compared with/without balloon occlusion. Factors influencing discrepancies between selective CTHA with/without balloon occlusion and the degree of iodized oil accumulation were investigated. Among 27 tumors, tumor enhancement on selective CTHA changed after balloon occlusion in 14 (decreased, 11; increased, 3). In 18 tumors, there was a discrepancy between tumor enhancement on selective CTHA with balloon occlusion and the degree of accumulated iodized oil, which was higher than the tumor enhancement grade in all 18. The tumorous portal perfusion defect on CTAP significantly decreased after balloon occlusion in 18 of 20 tumors (mean decrease from 21.9 to 19.1mm in diameter; p=0.0001). No significant factors influenced discrepancies between selective CTHA with/without balloon occlusion. Central area tumor location, poor tumor enhancement on selective CTHA with balloon occlusion, and no decrease in the tumorous portal perfusion defect area on CTAP after balloon occlusion significantly influenced poor iodized oil accumulation in the tumor. Tumor enhancement on selective CTHA frequently changed after balloon occlusion, which did not correspond to accumulated iodized oil in most cases.

Prospective diagnostic test accuracy comparison of computed tomography during arterial portography and Primovist magnetic resonance imaging in the pre-operative assessment of colorectal cancer liver metastases

ObjectivesTo assess and compare the accuracy and inter-observer agreement for the detection of liver lesions using Primovist magnetic resonance imaging (pMRI) and computed tomography during arterial portography (CTAP). MethodsPatients evaluated at St George Hospital Liver Unit for colorectal liver metastases (CRCLM) underwent CTAP as part of standard staging. pMRI was added to the pre-operative assessment. Two radiologists reported CTAP and two reported pMRI. The sensitivity and specificity of CTAP and pMRI were calculated using histopathology as the gold standard. ResultsComplete data were available for 62 patients corresponding to 219 lesions confirmed on histopathology. Agreement on the detection of lesions between the two radiologists that reported pMRI was higher than for CTAP (Kappa = 0.80 versus 0.74). Specificity of lesion detection for pMRI was 0.88 and 0.83 for CTAP (P = 0.112). Sensitivity for pMRI was 0.83 and 0.81 for CTAP. For patients who had chemotherapy before evaluation, pMRI had a significantly higher specificity than CTAP (0.79 versus 0.63, P = 0.011). ConclusionspMRI is less invasive, has a good inter-observer agreement, has comparable sensitivity and specificity to CTAP in the pre-chemotherapy population and demonstrates better specificity in patients assessed post-chemotherapy. pMRI is a valid alternative to CTAP in the assessment of CRCLM.

Hepatic pseudolymphoma: imaging–pathologic correlation with special reference to hemodynamic analysis

To clarify radiological findings and hemodynamic characteristics of hepatic pseudolymphoma, as compared with the histopathological findings. Radiological findings of ten histopathologically confirmed hepatic pseudolymphomas in seven patients were examined using US, CT, and MRI. Six patients also underwent angiography-assisted CT, including CT during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) to analyze hemodynamics. The nodules were depicted as hypoechoic on US, hypodense on precontrast CT, hypointense on T1-weighted images, and hyperintense on T2-weighted images. On contrast-enhanced CT/MRI, they showed various degrees of enhancement, and sometimes, perinodular enhancement was observed at the arterial dominant and/or equilibrium phase. On CTAP, the nodules showed portal perfusion defects, including some in the perinodular liver parenchyma. On CTHA, irregular bordered enhancement was observed in perinodular liver parenchyma on early phase, and continued until delayed phase. Some nodules had preserved intra-tumoral portal tracts. Histopathologically, the nodules consisted of marked lymphoid cells. In perinodular liver parenchyma, stenosis or disappearance of portal venules, caused by lymphoid cell infiltration in the portal tracts, was observed. Hepatic pseudolymphoma showed some characteristic radiological findings including hemodynamics on CT, MRI, and angiography-assisted CT. These findings are useful in the differentiation from hepatocellular carcinoma and other tumors.

Risk of hypervascularization in small hypovascular hepatic nodules showing hypointense in the hepatobiliary phase of gadoxetic acid-enhanced MRI in patients with chronic liver disease

The purpose of this study was to elucidate the incidence and risk factors for the progression of hypointense nodules observed in the hepatobiliary phase of gadoxetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-enhanced MRI) of hypervascular hepatocellular carcinoma (HCC). Hypovascular nodules (112) showing hypointensity in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were examined in 54 patients. All patients underwent computed tomography during hepatic arteriography and computed tomography during arterial portography (CTAP) within a month after Gd-EOB-DTPA-enhanced MRI. According to the tumor size, 112 nodules were divided into two groups: those >10 mm in diameter (group A, n = 39) and those ≤10 mm in diameter (group B, n = 73). The incidence of progression to hypervascular HCC was calculated using the Kaplan-Meier method. The incidence of hypervascularization was significantly higher in group A nodules than in group B nodules (p < 0.0001). Tumor size (p < 0.0001) and hypoattenuation in CTAP (p = 0.0004) showed significant correlation with hypervascularization. Hypointense nodules observed in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI with diameters of >10 mm had a high probability of hypervascularization.

Imaging Study of Early Hepatocellular Carcinoma: Usefulness of Gadoxetic Acid–enhanced MR Imaging

To describe imaging findings of early hepatocellular carcinoma (HCC) at gadoxetic acid-enhanced magnetic resonance (MR) imaging, dynamic contrast material-enhanced computed tomography (CT), CT during arterial portography (CTAP), and CT during hepatic arteriography (CTHA) and to compare the diagnostic performance of each modality for small (≤ 2 cm) HCC. The institute ethics committee deemed study approval unnecessary. One hundred eight resected small lesions in 64 patients were diagnosed as a dysplastic nodule (DN) (n = 12), progressed HCC (n = 66), or early HCC (n = 30). All but two patients underwent all imaging examinations. The imaging characteristics of the lesions with each modality were determined. To evaluate the diagnostic performance of the modalities, two radiologists graded the presence of HCC with use of a five-point confidence scale. The area under the receiver operating characteristic curve (A(z)), sensitivity, and specificity of each modality were compared. The imaging features that are statistically significant for differentiating an early HCC from a DN include fat-containing lesions at dual-echo T1-weighted MR imaging (seen in 16 of the 30 early HCCs and none of the DNs), low attenuation at unenhanced CT (seen in 13 of the 30 early HCCs and none of the DNs), low attenuation at CTAP (seen in 11 of the 30 early HCCs and none of the DNs), and low signal intensity at hepatocyte phase gadoxetic acid-enhanced MR imaging (seen in 29 of the 30 early HCCs and none of the DNs). The diagnostic performance of gadoxetic acid-enhanced MR imaging (A(z), 0.98 and 0.99) was significantly greater than that of contrast-enhanced CT (A(z), 0.87) and CTHA-CTAP (A(z), 0.85 and 0.86) owing to its significantly higher sensitivity (P < .001). Gadoxetic acid-enhanced MR imaging is the most useful imaging technique for evaluating small HCC, including early HCC.

Portal blood supply to locally progressed hepatocellular carcinoma after transcatheter arterial chemoembolization: Observation on CT during arterial portography

To analyze the clinical features of locally progressed hepatocellular carcinoma (HCC) supplied by portal blood (PB) after transcatheter arterial chemoembolization (TACE). This cohort included 12 tumors (mean diameter ± SD, 1.8 ± 0.8 cm) in 10 patients. PB supply to tumors was judged by CT during arterial portography (CTAP). Imaging data and the clinical course were retrospectively evaluated. Six tumors initially had a small tumor portion supplied by PB. In four tumors, TACE was incomplete because of technical problems. PB supply to recurrent tumors was demonstrated 7.3 ± 3.7 months after TACE. On follow-up arteriography, all embolized branches were occluded or severely attenuated. Four tumors showing a partial stain were treated by additional TACE (n = 3) or TACE plus radiofrequency (RF) ablation (n = 1), one without staining was treated by RF ablation, and seven were followed-up. All tumors progressed except for one treated by RF ablation. On serial CTAP images, relatively large-diameter portal veins directly entered 11 tumors (91.7%) and connected with intratumoral vessels in nine (75%). During follow-up, partial arterial supply was demonstrated in two tumors and additional TACE was performed. Nine patients died after 31.4 ± 16.2 months due to tumor progression (n = 8), or hepatic failure (n = 1). One patient has survived for 53 months despite multiple tumors. PB supply to locally progressed tumor after TACE became apparent on CTAP. Arterial damage by TACE, incomplete TACE, and preexisting tumor tissues supplied by PB may be the main causes.

An Imaging Study of a Ramification Pattern of Right Posterior Portal Vein Branch

Background: Our aim was to study the ramification pattern of the Right posterior portal vein branch and to compare our findings to Couinaud classification of the liver. Study design: The study protocol was approved by the institutional review board and written informed consent was obtained from all patients before procedures were performed. Our study includes 104 patients, all were Chinese who underwent helical Computed Tomography during Arterial Portography (CTAP). Subsequently, 3 dimensional portograms were reconstructed to verify the ramification patterns of the portal vein. Portal branching patterns of the right hemiliver were assessed. Results: In all 104 patients examined, three distinct types of anatomical branching patterns of the Right posterior portal vein branch were observed: • Type I: In 52 patients out of 104 (50%), the Right posterior portal branch represents a single trunk forming an arch like pattern and sending multiple branches to segment 6 and segment 7, see Figure 1 and Figure 2. • Type II: In 9 out of 104 patients (9%), the Right posterior portal vein branch showed trifurcation into posterosuperior, posteroinferior, and intermediate branches. The intermediate branch occupied the segmental border between segments S6 and S7, see Figure 3 and Figure 4. • Type III: In 43 out of 104 patients (41%), the Right posterior portal branch bifurcates into Posterosuperior P7 and Posteroinferior P6 third order portal branches as described by C. Couinaud in his homonymous segmental liver classification, see Figure 5 and Figure 6. Conclusions: According to Couinaud classification, the Right posterior portal branch bifurcates into third order Postero superior P7 and Posteroiferior P6 portal branches to supply segments S7 and S6. Our findings showed however, that it happened only in 41% of the cases. In 50% of the findings, the right posterior portal branch represented a single trunk forming an arch like pattern sending multiple branches. The smallest group of 9% showed trifurcation into posterosuperior, posteroinferior, and intermediate branches. Therefore we conclude that there is a discrepancy between the Atlas model of liver segmentation and our imaging findings. Based on these findings we can consider a right lateral sector as a unique segment in 50% of cases.

Outcome of small liver nodules detected by computed tomographic angiography in patients with hepatocellular carcinoma

Hepatic lesions identified by computed tomography (CT) during arterial portography (CTAP) or CT hepatic arteriography (CTHA) in hepatocellular carcinoma (HCC) patients are sometimes too small to be diagnosed as HCC. We undertook this cohort study to assess whether these small lesions are actually HCC, and to clarify the effectiveness of these imaging examinations in a clinical setting. We assessed the characteristics of 74 tiny lesions detected by CTAP and/or CTHA, but not by CT in 67 patients. Seven out of 10 nodules were histologically confirmed as HCC and 18 out of 64 lesions increased in size and showed typical findings of HCC during the follow-up period. Multivariate analysis revealed that the size of the main tumor (>30mm in diameter) was associated with the presence of tiny additional HCC lesions (P=0.002). These findings indicate that CTAP and CTHA are recommended for determining the stage of HCC, especially when the HCC nodule is larger than 30mm in diameter.

Detection of liver metastases secondary to pancreatic cancer: utility of combined helical computed tomography during arterial portography with biphasic computed tomography-assisted hepatic arteriography

This study was designed to define the diagnostic advantage of computed tomography during arterial portography (CTAP) combined with computed tomography-assisted hepatic arteriography (CTHA) for the preoperative detection of liver metastases secondary to pancreatic cancer compared with that of multidetector computed tomography (MDCT). From January 2002 to December 2007, we retrospectively studied 197 consecutive patients with pancreatic cancer. MDCT was performed on 192 patients prior to preoperative visceral angiography; 153 patients underwent CTAP + CTHA at the time of preoperative angiography. Liver metastases were identified in 39 patients by means of MDCT. Of the 153 patients who had no evidence of liver metastases on MDCT, 129 patients underwent CTAP + CTHA, and 53 of these 129 patients (41.1%) were diagnosed as having liver metastases that could not be detected by MDCT. These tumors missed by MDCT ranged from 3 to 15 mm in size. On CTAP + CTHA, a solitary nodule in the liver was detected in 11 patients, 2 nodules were detected in 6 patients, 3 lesions were detected in 2 patients, and ≧4 lesions were detected in 34 patients. The sensitivity and specificity of CTAP + CTHA versus MDCT were 94.2 versus 48.4% and 82.7 versus 97.9%, respectively. The combination of CTAP and CTHA is useful to confirm liver metastases and can potentially offer more accurate staging of pancreatic cancer compared with MDCT.

Triple-phase computed tomography during arterial portography with bolus tracking for hepatic tumors

The purpose of this study was to assess the usefulness of triple-phase computed tomography during arterial portography (CTAP) using a bolus-tracking technique. The subjects were 60 patients with hepatic tumors: 20 patients with metastatic liver tumors with a normal liver and 40 with hypervascular hepatocellular carcinoma (HCC) with liver cirrhosis. The region of interest was set in the portal vein, and CTAP was automatically started after the triggering threshold (180 HU) was reached. Three scans were performed: early phase (E), hepatic parenchymal phase (HP), and late phase (L). The scan start time of E-CTAP was measured. The detection rates of the HCC nodules were evaluated during each CTAP phase. CTAP was performed by bolus tracking without failure in any of the patients. The mean scan start times in the normal liver group and liver cirrhosis group were 14.3 +/- 1.34 s and 18.5 +/- 2.46 s, respectively, which were significantly different from each other. The detection rates of HCC nodules for E-CTAP, HP-CTAP, and L-CTAP were 29.6%, 100%, and 83.3%, respectively. The bolus-tracking technique enabled us to perform CTAP with optimal timing regardless of the portal blood flow dynamics.

Hepatocarcinogenesis: Multistep Changes of Drainage Vessels at CT during Arterial Portography and Hepatic Arteriography—Radiologic-Pathologic Correlation

To clarify the changes that occur in drainage vessels of dysplastic nodules and hepatocellular carcinoma (HCC) during hepatocarcinogenesis by using computed tomography (CT) during arterial portography (CTAP) and CT during hepatic arteriography (CTHA), with histologic findings as the reference standard. Institutional ethics committee approval and informed consent were obtained. According to the findings at CTAP and CTHA, 46 surgically resected hepatocellular nodules were classified into three types: type A (n = 18) (equivalent or decreased portal perfusion compared with background liver at CTAP, decreased arterial perfusion, and no corona enhancement [perinodular contrast material drainage] at CTHA), type B (n = 13) (no portal perfusion, increased arterial perfusion, and thin (< or = 2-mm) corona enhancement), or type C (n = 15) (no portal perfusion, increased arterial perfusion, and thick (> 2-mm) corona enhancement). We compared the histopathologic features and microangioarchitecture between the types. Type A nodules histologically consisted of dysplastic nodules and well-differentiated HCC; type B and C nodules were moderately differentiated HCC. Replacing growth was commonly observed in type A nodules, whereas compressing growth was more frequently seen in types B and C. Sixty percent of type C nodules had a fibrous capsule. There were significantly fewer intranodular hepatic veins in types B and C. Serial pathologic slices demonstrated continuity from intranodular capillarized sinusoids to hepatic veins in type A nodules and to surrounding hepatic sinusoids in type B nodules. In type C nodules, intranodular capillarized sinusoids were connected to extranodular portal veins either directly or through portal venules within the fibrous capsule. Drainage vessels of HCC change from hepatic veins to hepatic sinusoids and then to portal veins during multistep hepatocarcinogenesis.

Efficacy of double arterial phase dynamic magnetic resonance imaging with the sensitivity encoding technique versus dynamic multidetector-row helical computed tomography for detecting hypervascular hepatocellular carcinoma

The aim of this study was to evaluate the efficacy of double arterial phase dynamic magnetic resonance imaging (MRI) with the sensitivity encoding technique (SENSE dynamic MRI) for detection of hypervascular hepatocellular carcinoma (HCC) in comparison with double arterial phase dynamic multidetector-row helical computed tomography (dynamic MDCT). A total of 28 patients with 66 hypervascular HCCs underwent both double arterial SENSE dynamic MRI and dynamic MDCT. The diagnosis of HCC was based on surgical resection (n = 7), biopsy (n = 10), or a combination of CT during arterial portography (CTAP), CT during hepatic arteriography (CTA), and/or the 6-month follow-up CT (n = 49). Based on alternative-free response receiving operating characteristic (ROC) analysis, the diagnostic performance for detecting HCC was compared between double arterial phase SENSE dynamic MRI and double arterial phase dynamic MDCT. The mean sensitivity, positive predictive value, and mean Az values for hypervascular HCCs were 72%, 80%, and 0.79, respectively, for SENSE dynamic MRI and 66%, 92%, and 0.78, respectively, for dynamic MDCT. The mean sensitivity for double arterial phase SENSE dynamic MRI was higher than that for double arterial phase dynamic MDCT, but the difference was not statistically significant. Double arterial phase SENSE dynamic MRI is as valuable as double arterial phase dynamic MDCT for detecting hypervascular HCCs.

Multistep human hepatocarcinogenesis: correlation of imaging with pathology

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. The majority of HCCs develop in cirrhotic livers, and the early detection and characterization of this entity is very important. Pathologically, human HCC develops in a multistep fashion in the following sequence: from low-grade dysplastic nodule (LGDN), to high-grade dysplastic nodule (HGDN), early HCC, well-differentiated HCC, nodule-in-nodule HCC, and, finally, to moderately differentiated HCC. Differentiation between early HCC and DN is the most important issue in the clinical setting. CT during hepatic angiography (CTHA) and CT during arterial portography (CTAP) are the most sensitive tools in the differentiation of premalignant/borderline lesions (LGDN and HGDN) and early HCC. Recent progress in imaging modality, especially Sonazoidenhanced US and Gd-EOB-DTPA MRI, is starting to play a very important role in the imaging of multistep hepatocarcinogenesis, resulting in changing the therapeutic strategy of these nodular lesions associated with liver cirrhosis.

Detection of hepatocellular carcinoma by CT during arterial portography using a cone-beam CT technology: comparison with conventional CTAP

To evaluate the detectability of hepatocellular carcinoma (HCC) by computed tomography during arterial portography (CTAP) using cone-beam CT technology (CBCTAP) by comparing it with conventional CTAP. Forty-four HCC lesions (mean diameter 1.9 +/- 1.1 cm) of 24 patients who sequentially underwent conventional CTAP and CBCTAP during the same angiography session were evaluated. CBCTAP findings of each tumor were classed into three grades as compared to conventional CTAP: optimal; suboptimal; and nondiagnostic. All CBCTAP images had image artifacts from the catheter placed in the superior mesenteric artery and enhanced portal veins. Additionally, the contrast between HCC lesion and surrounding liver parenchyma of CBCTAP images was less than that of CTAP images. Of the 44 tumors, findings of 31 nodules (mean 2.2 +/- 1.2 cm) (70.5%) were classed as optimal. Eight nodules (mean 1.4 +/- 0.8 cm) (18.2%) were classed as suboptimal. Five nodules (mean 1.0 +/- 0.1 cm) (11.4%) including two located in the outside of field of view were classed as nondiagnostic. CBCTAP had sufficient image quality to detect almost all small HCC lesions compared to conventional CTAP and could depict approximately 89% of HCC nodules, including eight suboptimal lesions.

Superiority of CT Arterioportal Angiography to Contrast-Enhanced CT and MRI in the Diagnosis of Hepatocellular Carcinoma in Nodules Smaller than 2 cm

To evaluate the effectiveness of computed tomography (CT) arterioportal angiography in the diagnosis of hepatocellular carcinoma (HCC) in nodules smaller than 2 cm, we compared the findings of CT during arteriography (CTA) and CT during arterial portography (CTAP) with those of enhanced CT and enhanced magnetic resonance imaging (MRI). Sixty-eight nodules smaller than 2 cm in 53 patients with liver cirrhosis were classified into three groups of CTA and CTAP: (group 1) hyperattenuation on CTA, and hypoattenuation on CTAP (56 nodules, 41 patients); (group 2) hypoattenuation on CTA, and hypoattenuation on CTAP (10 nodules, 10 patients); (group 3) hypoattenuation on CTA, and hyperattenuation on CTAP (2 nodules, 2 patients). Histologically, 96% (54/56), 80% (8/10), and 100% (2/2) of the nodules in groups 1, 2 and 3, respectively, were diagnosed as HCC. In group 1, enhanced CT or enhanced MRI confirmed hypervascularity in only 77% (30/39) and venous washout in 21% (8/39). In groups 2 and 3, enhanced CT or enhanced MRI on 7 and 2 nodules, respectively, revealed no hypervascularity (0%). The results suggested that CT arterioportal angiography is superior to enhanced CT and MRI in nodules smaller than 2 cm for diagnosing HCC (p < 0.01 group 1, p < 0.01 group 2).

Combination of CT during arterial portography and double-phase CT hepatic arteriography with multi-detector row helical CT for evaluation of hypervascular hepatocellular carcinoma

To evaluate the diagnostic accuracy of the combination of computed tomography (CT) during arterial portography (CTAP) and double-phase CT hepatic arteriography (CTHA) with multidetector-row CT (MDCT) for the evaluation of hepatocellular carcinomas (HCCs) in patients with cirrhosis. The combination of CTAP and double-phase CTHA was performed on 46 patients with 54 nodular HCCs. Three readers reviewed the images obtained with CTAP alone, first-phase CTHA alone, double-phase CTHA, and the combination of CTAP and double-phase CTHA. The review of the images was conducted on a segment-by-segment basis, with 368 hepatic segments, including 50 segments with 54 HCCs, reviewed for detection of HCCs with the aid of a five-point confidence scale. Diagnostic accuracy was evaluated by comparing the receiver-operating characteristic (ROC) analysis results. The sensitivity for detecting HCCs was significantly higher with either double-phase CTHA or the combination of CTAP and double-phase CTHA than with first-phase CTHA alone (90 and 93 versus 85%, respectively, p<0.01). The specificity for detecting HCCs was significantly higher with the combination of CTAP and double-phase CTHA than with CTAP alone (97 and 94%, respectively, p<0.01). The positive predictive values for detecting HCCs were significantly higher with double-phase CTHA than with first-phase CTHA alone (86 and 82%, respectively, p<0.05). The area under the ROC curve (Az) values were significantly higher with the combination of CTAP and double-phase CTHA (0.983) than with first-phase CTHA alone (0.959; p<0.05). The combination of CTAP and double-phase CTHA with MDCT significantly enhances the detection of HCC.

Hypervascular hepatocellular carcinoma: Combined dynamic MDCT and SPIO‐enhanced MRI versus combined CTHA and CTAP

Recently, many diagnostic modalities have been developed for the detection of hepatocellular carcinoma (HCC). Of these, a less invasive and more accurate diagnostic procedure is desirable. This study was undertaken to compare combined dynamic multidetector row helical computerized tomography (MDCT) and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) with combined CT hepatic arteriography (CTHA) and CT during arterial portography (CTAP) for the detection of hypervascular HCC. Forty-eight patients with 56 pathologically proved hypervascular HCCs (less than 5.0 cm in diameter) underwent dynamic MDCT and SPIO-enhanced MRI, as well as CTHA and CTAP. The images were reviewed by four independent and blinded readers on a tumor-by-tumor basis. The mean areas under alternative-free response receiver operating characteristic curve (Az) for combined dynamic MDCT and SPIO-enhanced MRI (IV set) and combinedCTHA and CTAP (IA set) were comparable (0.948 and 0.969, respectively, P > 0.05), although the Az value of the IV set was significantly lower than that of the IA set in HCCs smaller than or equal to 1.5 cm (0.867 and 0.937, respectively, P = 0.033). The mean sensitivity and positive predictive value of the IV set were similar to those of the IA set. Combined dynamic MDCT and SPIO-enhanced MRI showed a diagnostic accuracy comparable to intra-arterial contrast-enhanced CT (CTHA and CTAP) for hypervascular HCC, and may be a useful diagnostic option prior to curative treatments of hypervascular HCC, although a limitation exists in detecting HCCs smaller than or equal to 1.5 cm.

Imaging diagnosis of hepatic metastases of pancreatic carcinomas: significance of transient wedge-shaped contrast enhancement mimicking arterioportal shunt

We aimed to evaluate the imaging findings of hepatic metastases from pancreatic cancers, especially wedge-shaped enhancement and its etiology. Dynamic CT and MR images were performed in 87 patients with liver metastases from pancreatic carcinomas, and CT during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) in 51 patients. Liver metastases were multiple in 84 patients (97%) and solitary in only three (3%). In 44 of 87 patients (51%), all liver metastases showed ring-like enhancement compatible with metastatic adenocarcinomas on dynamic CT and/or dynamic MR imaging. In 37 patients, more than one metastatic lesion showed wedge-shaped contrast enhancement on dynamic CT, dynamic MRI and CTHA, and wedge-shaped perfusion defect on CTAP adjacent to metastatic tumors. Six patients showed multiple wedge-shaped enhancements, which were initially diagnosed as multiple arterioportal shunts (AP shunts). However, metastatic tumors appeared within the area of wedge-shaped enhancement and increased in size on follow-up CT and/or MR images. After all, 43 of 87 patients (49%) had AP shunt like contrast enhancement adjacent to liver metastases. Liver metastases from pancreatic carcinomas frequently show transient wedge-shaped enhancement, and should not be misdiagnosed as nontumorous arterioportal shunts.