CT During Hepatic Arteriography Research Articles

Visualization of blood drainage area from hypervascular hepatocellular carcinoma on ultrasonographic images during hepatic arteriogram: Comparison with depiction of drainage area on contrast‐enhanced ultrasound

Corona enhancement is the visualized drainage area from a hypervascular tumor observed on single-level dynamic computed tomography during hepatic arteriography (CTHA) and is thought to be a high-risk area for micrometastases. However, because it cannot be visualized with ordinary ultrasonography (US), we aimed to visualize corona enhancement on US by means of arterial injection of the contrast material and to measure its thickness. Forty-one hypervascular hepatocellular carcinoma (HCC) cases were prospectively investigated. US during hepatic arteriography (USHA) was executed by means of selective injection of the contrast material perfluorobutane (Sonazoid) from the hepatic artery. Ordinary contrast-enhanced US with venous administration of contrast material and single-level dynamic CTHA were also performed. Corona enhancement was observed in 36 cases (88%) on USHA and in 25 cases (61%) on single-level dynamic CTHA. The thickness of corona enhancement of 36 cases visualized with USHA ranged 3.1-18.4 mm and the mean thickness ± standard deviation was 6.0 ± 3.0 mm. Thickness of corona enhancement was less than 10.0 mm in 34 cases (94%). Corona enhancement could be visualized even on US images, and the average thickness of them was 6 mm.

Assessment of arterial hypervascularity of hepatocellular carcinoma: comparison of contrast-enhanced US and gadoxetate disodium-enhanced MR imaging

To compare contrast-enhanced (CE) ultrasound with gadoxetate disodium-enhanced magnetic resonance (MR) imaging in the assessment of arterial hypervascularity of hepatocellular carcinoma (HCC) and dysplastic nodule (DN), with CT during hepatic arteriography (CTHA) as the reference standard. This study included 54 consecutively diagnosed patients, with 57 histologically confirmed HCCs and 3 DNs (high-grade). All patients underwent CE ultrasound, gadoxetate disodium-enhanced MR imaging and CTHA. Two trained diagnostic radiologists interpreted the CTHA images and rated the degree of intratumoral arterial vascularity by consensus using a five-point confidence scale as the reference standard. In the observer study, the degrees of vascularity on CE ultrasound and gadoxetate disodium-enhanced MR images were qualitatively analysed by four independent readers using a five-point confidence scale. Diagnostic accuracy was analysed by receiver-operating characteristic (ROC) analysis. The diagnostic accuracies of the average area under the ROC curve (AUC) were significantly greater with CE ultrasound (average AUC: 0.94; 95% confidence interval [CI]: 0.88-1.00) than with gadoxetate disodium-enhanced MR imaging (average AUC 0.84, 95% CI 0.74-0.93, P = 0.0014). Contrast-enhanced ultrasound yields a significantly higher AUC value than gadoxetate disodium-enhanced MR imaging in the assessment of arterial hypervascularity of HCC and DN. • Arterial hypervascularity is an important feature determining treatment options in hepatocellular carcinoma. • It can be assessed by contrast-enhanced (CE) ultrasound or magnetic resonance (MR) imaging. • CE ultrasound was more accurate than Gd-EOB-DTPA MRI in assessing intratumoral vascularity. • Hypovascular hepatic nodules should be further investigated using CE ultrasound.

Well-differentiated Hepatocellular Carcinoma Detected as Hypovascularity by Only CT during Hepatic Arteriography

We describe a well-differentiated hepatocellular carcinoma (HCC) with alcohol-related liver cirrhosis in a 69-year-old man. Ultrasonography (US) disclosed a 10 mm hypoechoic nodule in segment 4; Sonazoid contrast-enhanced US and gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) revealed no defect in either the Kupffer phase or the hepatobiliary phase. Computed tomography during hepatic arteriography (CTHA), however, revealed a hypovascular nodule, but CT during arterial portography showed no perfusion defect. Histological analysis indicated a well-differentiated HCC. Thus, our detection of well-differentiated HCC disclosed by only CTHA attested to the efficiency of this modality, suggesting that it is more sensitive than Gd-EOB-GTPA-enhanced MRI.

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.

Detection of small hypervascular hepatocellular carcinomas by EASL criteria: Comparison with double-phase CT during hepatic arteriography

To compare the detectability of small hypervascular hepatocellular carcinoma (HCC) between double-phase CT during hepatic arteriography (CTHA) criteria (hypervascular on the early-phase of CTHA and corona enhancement on the late-phase of CTHA) widely introduced in Japan and EASL criteria (hypervascular on the arterial dominant phase and wash out on the equilibrium phase of dynamic CT and/or MRI). 116 hypervascular HCC lesions (≤2 cm) of 38 patients were evaluated. CTHA was performed in every patient, both dynamic CT and dynamic MRI in 22 patients, only dynamic CT in 8, and only dynamic MRI in 8. Among them, the detectability of HCC lesions was statistically analyzed with χ2 test. Double-phase CTHA detected all HCCs. Dynamic CT revealed 38 (40%) of 95 small HCCs; during dynamic MRI 38 (40%) of 95 small HCCs were detected. The difference between dynamic CT or dynamic MRI and CTHA was statistically significant (p<0.05). The detectability of small hypervascular HCC on dynamic CT and dynamic MRI was almost the same and significantly lower as compared to that of CTHA. When comparing differences in the results of HCC treatment, differences in the diagnostic criteria applied should always be kept in mind.

Diagnostic Value of SPIO-mediated Breath-hold, Black-blood, Fluid-attenuated, Inversion Recovery (BH-BB-FLAIR) Imaging in Patients with Hepatocellular Carcinomas

We assessed the value of adding a breath-hold, black-blood, fluid-attenuated, inversion recovery (BH-BB-FLAIR) sequence with a small motion-probing gradient (b=10 s/mm(2)) using superparamagnetic iron oxide (SPIO) to our present studies that utilize SPIO to detect hepatocellular carcinoma (HCC). We used inversion recovery (IR) in a FLAIR sequence to suppress signals from cysts and a low b-value to suppress vessel signals and provide higher signal to noise than that using high b-value diffusion-weighted imaging. Use of SPIO is expected to reduce the signal in both normal liver parenchyma and in most benign lesions. In 19 patients, we reviewed 38 HCC nodules diagnosed by CT arterioportography (CTAP) and CT during hepatic arteriography (CTHA). We divided SPIO-mediated images into sets, those obtained with and without BH-BB-FLAIR. Six radiologists individually interpreted the 2 image sets and sorted them by their confidence levels for the presence of HCC, and we calculated the area under the receiver operating characteristic (ROC) curve (Az) for each image set. On images obtained with BH-BB-FLAIR after SPIO administration, 33 of the 38 HCC nodules appeared as areas of high signal and cyst signal was extinguished. The ROC analysis showed significantly higher Az values in the set with BH-BB-FLAIR (0.89) than in the set without (0.83). Adding BH-BB-FLAIR to existing SPIO-mediated imaging protocols improved detection of HCC nodules and added only 24 s to the scan time.

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.

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Diagnosis by CTHA (CT during hepatic arteriography) and CTAP (CT during arterio-portography) is indispensable in the treatment of hepatocellular carcinoma (HCC). An IVR-CT system makes it possible to perform accurate diagnosis and treatment of HCC in a short period of time. In recent years, attention has been drawn to cone-beam CT (CBCT) using a flat panel detector (FPD) angio-system, and the application of CBCT for CTAP and CTHA has been reported. However, it is well known that CBCT easily generates artifacts on the images, so it is necessary to use CBCT according to the intended purpose. The purpose of this study was to evaluate 3-D images reconstructed by MDCT or CBCT, image noise, and low-contrast resolution in a phantom with a tumor mimic model. From our results, CBCT images showed distortion and blurring, and it was difficult to visualize a tumor model of 7 mm or less. In addition CBCT can create only a small area of 3-D vascular mapping. In conclusion, it is considered that CBCT cannot be used in place of conventional CTHA or CTA for the treatment of HCC.

コロナ様濃染を認めた限局性結節性過形成(FNH)の1症例

A hepatic nodule was detected in segment 5/6 on abdominal US study in a 28 year-old male. The nodule was 7cm in diameter and the early phase of contrasted US, CT and MRI images showed spoke-wheel like vessels radiating from the center. No defect images were observed on postvascular phase contrasted US and SPIO MRI, which indicated the presence of Kupffer cells in the nodule. The nodule was diagnosed as a focal nodular hyperplasia (FNH) based on histological findings. The late phase of single level dynamic CT during hepatic arteriography (CTHA) showed corona enhancement of the nodule, which is considered to be characteristic of hypervascular metastatic liver tumors, hyperplastic nodules and HCCs. In our case, the drainage flow from the nodule may have been visualized as corona enhancement via the pathway from the sinusoid in the nodular periphery to the one in the adjacent and contiguous parenchyma.

Detection of hypervascular malignant foci in borderline lesions of hepatocellular carcinoma: comparison of dynamic multi-detector row CT, dynamic MR imaging and superparamagnetic iron oxide-enhanced MR imaging

The study object was to retrospectively compare the detection rate of hypervascular foci visualized by CT during hepatic arteriography (CTHA) in borderline nodules, which was observed upon cirrhotic livers, on dynamic MDCT, dynamic gadolinium-enhanced MR (dynamic MR), and SPIO-enhanced MR imaging. Eighty-five nodules in 49 patients with cirrhosis were evaluated. When a part of the nodule showed hyperdensity relative to the surrounding areas of the nodule on CTHA, it was defined as "hypervascular focus." The relationships between the dynamic MDCT and dynamic MR and SPIO-enhanced MR imaging findings of these foci were analyzed using X(2) test. Hypervascular foci were detected in 17 (53%) of 32 on the arterial dominant phase of dynamic MDCT, in 19 (37%) of 51 on the arterial dominant phase of dynamic MR and in 6 (26%) of 23 on SPIO-enhanced MR imaging. Arterial dominant phase of dynamic MDCT demonstrated a significantly higher detection rate of hypervascular foci less than 5 mm in diameter than did dynamic and SPIO MR imaging (p<0.05). Hypervascular foci in borderline nodules could be better visualized by dynamic MDCT than by gadolinium- and SPIO-enhanced MR imaging. Dynamic MDCT is recommended for the follow-up examination of hypovascular borderline lesions.

Iodized Oil Accumulation in Hypervascular Hepatocellular Carcinoma after Transcatheter Arterial Chemoembolization: Comparison of Imaging Findings with CT during Hepatic Arteriography

To compare the degree of tumor enhancement seen on computed tomography (CT) during hepatic arteriography (CT/HA) performed before transcatheter arterial chemoembolization (TACE) versus that determined based on the accumulation of iodized oil seen on CT images obtained after TACE in patients with hypervascular hepatocellular carcinoma (HCC) and evaluate the discrepancy in findings between the two imaging modalities (more or less oil accumulation after TACE compared with enhancement on CT/HA). CT/HA, TACE, and iodized oil CT after TACE were performed in 69 patients with 83 hypervascular HCCs with use of an interventional CT system. The degree of contrast enhancement of the lesion on CT/HA and the iodized oil accumulation on unenhanced CT after TACE were compared. Among 83 HCCs, the degree of enhancement on CT/HA before TACE corresponded to the iodized oil accumulation on CT in 56 (67.5%). Fifteen of 83 HCCs (18%) showed incomplete or poor accumulation of iodized oil despite good enhancement on CT/HA images. Twelve of 83 HCCs (14.5%) showed moderate or complete accumulation of iodized oil despite poor or no enhancement on CT/HA images. In particular, in two patients with occluded portal veins, iodized oil did not accumulate in the tumor despite good visualization on CT/HA. Although iodized oil accumulation in hypervascular HCCs correlates with the degree of lesion enhancement on CT/HA in most cases, a discrepancy may occur in a substantial number of cases, which likely affects the prediction of therapeutic effects in hypervascular HCCs.

Repeated radiofrequency ablation for the distant recurrence in the liver in patients with chronic hepatitis C virus infection achieving long‐term survival

Recurrence of hepatocellular carcinoma (HCC) is frequently observed in patients with hepatitis C virus (HCV) infection and the incidence of HCC recurrence is as high as 20% in these patients even after a complete curative treatment is given for the HCC nodules. We report a 57-year-old female who was referred to our hospital for the treatment of a HCC nodule of 1.8 cm diameter in S5 and having liver cirrhosis of Child-Pugh A classification with HCV infection in April 1999. The HCC nodule showed hypervascularity by computed tomography during hepatic arteriography (CTHA) and was coagulated by microwave under peritoneoscopy. Complete necrosis was confirmed by enhanced-CT scan after microwave coagulation. Thereafter, interferon alfa-2b (3MU, twice weekly) was given but HCV RNA continued to be positive. Thereafter, recurrence of HCC was noted five times in S1, S2, S6; treatment by radiofrequency ablation was given four times; and transarterial chemoembolization was carried out once. Since January 2004, peg-interferon alfa-2a (90 microm/week) has been administered, and no recurrence has been detected until August 2005. She is currently 63 years old, and quite well. Five-year-survival rate in HCC patients treated by radiofrequency ablation is 62.7% in our hospital, however, the recurrence rate is as high as 26.4% per year in the patients with chronic HCV infection. It is a point of controversy when liver transplantation should be recommended in HCC patients with liver cirrhosis of Child-Pugh A classification having chronic HCV infection because of the high incidence of recurrence.

Multiple necrotic nodules of the liver simulating liver metastasis

A 70-year-old man was referred to our hospital due to anemia and elevated serum tumor marker levels. He had advanced colon cancer, and hepatic lesions were found incidentally. On ultrasonography (US) and computed tomography (CT), the hepatic lesions had a maximum diameter of 20 mm and were located in Couinaud's segments V, VI, VII, and VIII, which suggested liver metastasis. On early- and late-phase CT during hepatic arteriography (CTHA), all of the lesions had rim enhancement. On early-phase CT during arterioportography (CTAP), all of the lesions were seen as nodules with an irregular perfusion defect, and on late-phase CTAP, all the lesions gradually became iso-dense, and their shape and size changed. Based on the CTAP findings, these lesions were thought to be fibrotic tumors. Partial resection of the liver (including the lesions in Couinaud's segments V and VIII) was done. Histological examination revealed that the lesions were necrotic nodules. Thus, CT angiography (CTHA and CTAP) was useful for identifying necrotic nodules, because their appearance on this modality is different from that of liver metastases.

Hemodynamics of small sclerosing hepatocellular carcinoma without fibrous capsule: evaluation with single-level dynamic CT during hepatic arteriography

The tumor drainage pathway of a hypervascular liver tumor without fibrous capsule was evaluated histologically and using single-level dynamic CT during hepatic arteriography (CTHA) in a case of sclerosing type of hepatocellular carcinoma. This tumor had a thin corona on CTHA, which represented drainage from the tumor sinusoids to the surrounding liver sinusoids. Additionally, the corona of the hypervascular tumor was thinner without than with the fibrous capsule.

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.

Multidetector helical CT plus superparamagnetic iron oxide-enhanced MR imaging for focal hepatic lesions in cirrhotic liver: A comparison with multi-phase CT during hepatic arteriography

The aim of this study was to evaluate multidetector helical computed tomography (MDCT), superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging, and CT arterial portography (CTAP) and CT during hepatic arteriography (CTHA) for the detection and diagnosis of hepatocellular carcinomas (HCC). This included visual correlations of MDCT and SPIO-MR imaging in the detection of HCC using receiver operating characteristic (ROC) analysis. Twenty-five patients with 57 nodular HCCs were retrospectively analyzed. A total of 200 segments, including 49 segments with 57 HCCs, were reviewed independently by three observers. Each observer read four sets of images (set 1, MDCT; set 2, unenhanced and SPIO-enhanced MR images; set 3, combined MDCT and SPIO-enhanced MR images; set 4, combined CTAP and CTHA). The mean Az values representing the diagnostic accuracy for HCCs of sets 1, 2, 3, and 4 were 0.777, 0.814, 0.849, and 0.911, respectively, and there was no significant difference between sets 3 and 4. The sensitivity of set 4 was significantly higher than those of set 3 for all the lesions and for lesions 10 mm or smaller ( p < 0.05); however, for lesions larger than 10 mm, the sensitivities of the two sets were similar. No significant difference in positive predictive value and specificity was observed between set 3 and set 4. Combined MDCT and SPIO-enhanced MR imaging may obviate the need for more invasive CTAP and CTHA for the pre-therapeutic evaluation of patients with HCC more than 10 mm.

Cirrhotic Nodules: Association between MR Imaging Signal Intensity and Intranodular Blood Supply

To retrospectively determine whether there is a relationship between the intranodular blood supply evaluated at computed tomography (CT) during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) and the magnetic resonance (MR) imaging signal intensity of nodules associated with cirrhosis. Neither institutional review board approval nor informed consent was required for retrospective reviews of medical records and images. One hundred fourteen hepatocellular nodules 10 mm or greater in largest diameter in 58 patients (39 men, 19 women; mean age, 61 years) with cirrhosis were evaluated at CTAP, CTHA, and MR imaging. The CTAP and CTHA nodule findings were divided into three main types: Type A nodules were isoattenuating at CTAP and hypoattenuating at CTHA; type B nodules, slightly hypoattenuating at CTAP and hypoattenuating at CTHA; and type C nodules, strongly hypoattenuating at CTAP and hyperattenuating at CTHA. The relationships between the CTAP and CTHA findings and the MR imaging signal intensity among these nodules were analyzed by using the chi(2) test. On T1-weighted MR images, 27 (63%) of 43 type A nodules were hyperintense, nine (39%) of 23 type B nodules were isointense, and 19 (48%) of 40 type C nodules were hypointense; differences were not significant. On T2-weighted MR images, 31 (72%) of 43 type A nodules were hypointense (P < .05), 12 (52%) of 23 type B nodules were isointense, and 34 (85%) of 40 type C nodules were hyperintense (P < .05). There was a significant association between intranodular blood supply and nodule signal intensity on T2-weighted MR images. However, study findings did not show whether the blood itself (ie, blood volume or blood flow amount) directly influenced the signal intensity.

Communicating Arcade between the Right and Left Hepatic Arteries: Evaluation with CT and Angiography during Temporary Balloon Occlusion of the Right or Left Hepatic Artery

To evaluate prospectively the relationship between the arterial collateral system at the hepatic hilum and the blood supply to the hilar bile duct by using computed tomography (CT) and angiography during temporary balloon occlusion of the right or left hepatic artery. Institutional review board approval and informed consent were obtained. The study included 13 patients with no lesions at the hepatic hilum (eight men and five women; age range, 41-78 years; mean, 65.8 years). After serial angiographic studies were performed for preoperative evaluation or transcatheter arterial chemoembolization, a 5.5-F catheter with an occlusion balloon was positioned in the right or left hepatic artery. Eleven patients underwent angiography of the left hepatic artery with temporary occlusion of the right hepatic artery, and two patients underwent angiography of the right hepatic artery with temporary occlusion of the left hepatic artery. In addition, 11 patients underwent single-level dynamic CT during hepatic arteriography (CTHA) with temporary occlusion of the right or left hepatic artery. The images from angiography and CTHA were interpreted by two authors who assessed the existence of the arterial communication and its branching points, location, and relationship to the hilar bile duct and caudate lobe. During temporary occlusion of the right or left hepatic artery, the communicating arcade (CA) between the right and left hepatic arteries was immediately evident in all patients. On the left side, the CA originated from the segment IV artery in eight patients (62%) and from the left hepatic artery in five (38%). On the right side, the CA originated from the right anterior hepatic artery in six patients (46%), the right hepatic artery in two (15%), and both arteries in five (38%). The CA was extrahepatically located close to the hilar bile duct and forked into a few branches to the caudate lobe. The CA may play an important role not only in the interlobar arterial collateral system but also in the blood supplies to the caudate lobe and hilar bile duct.

Superparamagnetic iron oxide-enhanced MR imaging for focal hepatic lesions: a comparison with CT during arterioportography plus CT during hepatic arteriography

We aimed to evaluate the efficacy of a breath-hold superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging protocol for the detection of focal hepatic lesions, in comparison with a non-breath-hold SPIO-enhanced imaging protocol and computed tomography during arterioportography (CTAP) plus CT during hepatic arteriography (CTHA). Findings of SPIO-enhanced MR imaging and CTAP/CTHA for 24 hepatic metastases in 17 patients and 29 HCCs in 21 patients were analyzed. All patients underwent breath-hold SPIO-enhanced MR imaging (1.5 tesla), breath-hold plus non-breath-hold SPIO-enhanced MR imaging, and CTAP plus CTHA prior to partial hepatectomy or laparoscopic ablation therapy. Histopathology for lesion characterization and intraoperative ultrasound for lesion detection were available for all patient. Breath-hold SPIO-enhanced MR imaging consisted of T2-weighted single-short fast spin echo (FSE), T2-weighted (T2W) FSE, T2*-weighted gradient echo (GRE), and T1-weighted GRE. For the non-breath-hold imaging protocol, respiratory-triggered, fat-suppressed T2W-FSE was added to the breath-hold MR imaging protocol. Double phase CTAP plus CTHA was performed on an angio-CT system. To compare the three imaging protocols, three radiologists performed blind film reading, and all data, on a hepatic segment-to-segment basis, were entered for alternative free-response receiver-operating characteristic (AFROC) analysis. ROC analysis showed that there was no significant difference in the area under the AFROC curve (A1) value for metastases and HCCs among the three protocols; the breath-hold SPIO-enhanced MR imaging protocol, non-breath-hold MR imaging protocol, and CTAP plus CTHA. The breath-hold SPIO-enhanced MR imaging protocol showed a sensitivity, specificity, and accuracy equivalent to the non-breath-hold MR imaging protocol and CTAP plus CTHA. As a preoperative test, SPIO-enhanced MR imaging could have the potential to replace CTAP plus CTHA in a certain clinical setting.