Detection of corona enhancement of hypervascular hepatocellular carcinoma by C-arm dual-phase cone-beam CT during hepatic arteriography.

The purpose of this study was to evaluate the detectability of corona enhancement around the hypervascular hepatocellular carcinoma (HCC) by dual-phase cone-beam computed tomography during hepatic arteriography (CBCTHA). Dual-phase CBCTHA was performed for 71 HCC lesions (mean ± SD 1.7 ± 0.9 cm), including seven presenting a nodule-in-nodule appearance and nine hypervascular pseudolesions. The first scan was performed during injection of 30-40 ml half-diluted contrast material at a rate of 1.5-2 ml/s through the hepatic artery. Scanning was initiated 7 s after the beginning of contrast material injection. The second scan was started 30 s after the end of the first scan. Detectability of corona enhancement on second-phase CBCTHA was evaluated. Thickness of corona enhancement was also analyzed as thin (≤2 mm) or thick (>2 mm). Corona enhancement was detected in 63 (88.7%) of 71 tumors (1.8 ± 0.9 cm), but it was not detected in eight tumors (1.0 ± 0.2 cm). Thin corona enhancement was seen in 18 tumors (1.2 ± 0.5 cm), and thick corona enhancement was seen in 45 tumors (2.0 ± 0.9 cm). There was a significant difference in tumor diameter between tumors with and those without corona enhancement (P = 0.0157) and between thin and thick corona enhancement (P = 0.001). In all seven early-stage tumors, corona enhancement was demonstrated around the hypervascular focus within the hypovascular tumor portion. None of the nine pseudolesions showed any corona enhancement. Dual-phase CBCTHA depicted corona enhancement in 88.7% of hypervascular HCC lesions. This technique may improve the diagnostic accuracy of HCC.

Hepatocellular carcinoma in the caudate lobe of the liver: variations of its feeding branches on arteriography.

There are usually multiple caudate arteries arising from the right, left, and middle hepatic arteries, and they are frequently connected to each other. Therefore, hepatocellular carcinoma (HCC) in the caudate lobe is frequently fed by multiple branches arising from different origins. HCC located in the Spiegel lobe is usually fed by the caudate arteries derived from the right and/or left hepatic artery. HCC in the paracaval portion is mainly fed by the caudate artery derived from the right hepatic artery; with low frequency, it is fed by the caudate artery derived from the left hepatic artery. HCC in the caudate process is usually fed by the caudate artery derived from the right hepatic artery. Because of the complexity and overlap of vascular territories, the tumor-feeding branch of a recurrent HCC lesion in the caudate lobe frequently changes on follow-up arteriograms. In addition, several extrahepatic collateral vessels supply the recurrent tumor. To perform effective transcatheter arterial chemoembolization (TACE) for HCC in the caudate lobe, radiologists should have sufficient knowledge of vascular anatomy supplying HCC in the caudate lobe.

Inferior phrenic arteries: angiographic anatomy, variations, and catheterization techniques for transcatheter arterial chemoembolization.

The inferior phrenic artery (IPA) is the most common extrahepatic collateral vessel to hepatocellular carcinoma (HCC); however, there are many anatomical variations in its origin and branches. In addition, the IPA is frequently reconstructed through several pathways, mainly through the retroperitoneal network, because of the occlusion of its orifice due to atherosclerosis or previous catheter manipulation. Infrequently, selective catheterization into the IPA is impossible even using a microcatheter, particularly in the IPA that originates from the proximal or distal portion of the celiac trunk or from the aorta with an acute angle. In this article, we describe anatomical variations of the IPA and catheterization techniques, such as a catheter with a large side hole and a catheter with a cleft, to facilitate catheterization into the IPA that is difficult using a conventional coaxial technique. Radiologists should have sufficient knowledge of such variations and catheterization techniques to perform transcatheter arterial chemoembolization for HCCs through the IPA effectively and safely.

Technical success rates and long-term patency of endovascular treatment for occluded native hemodialysis fistulas: comparison between thrombotic occlusion and nonthrombotic occlusion.

PURPOSE: This study evaluated the technical success and long-term patency of endovascular treatment for occluded native hemodialysis fistulas caused by thrombotic occlusion (TO) and nonthrombotic occlusion (NTO). MATERIALS AND METHODS: This cohort included 96 consecutive occlusions (70 TOs and 26 NTOs) at the forearm. Clinical success and patency rates of endovascular treatment were calculated and compared between the TO and NTO groups. RESULTS: Overall clinical success rate was 91.6%; and primary, assisted primary, and secondary patency rates at 1, 2, and 3 years were 49.6%, 30.7%, and 28.3%, respectively; 73.8%, 48.3%, and 48.3%, respectively; and 80.7%, 72.3%, and 66.2%, respectively. Clinical success rates of the TO and NTO groups were 91.4% and 92.3%, respectively. The 1-, 2-, and 3-year primary, assisted primary, and secondary patency rates of the TO group were 54.4%, 29.3%, and 25.6%, respectively; 70.7%, 49.4%, and 49.4%, respectively, and 78%, 68.8%, and 64,2%, respectively. Those of the NTO group were 38.9%, 32.4%, and 32.4%, respectively; 81.2%, 47.3%, and 40.6%, respectively; and 87%, 80.3%, and 70.2%, respectively. There were no significant differences between the clinical success and patency rates of the two groups. CONCLUSION: Occluded native hemodialysis fistulas were restored with high frequency, without significant differences between clinical success and patency in the TO and NTO groups.

Chemoembolization for the treatment of large hepatocellular carcinoma.

PURPOSE: To retrospectively evaluate the efficacy of chemoembolization for inoperable hepatocellular carcinoma (HCC) tumors larger than 5 cm in diameter. MATERIALS AND METHODS: Chemoembolization was performed in 30 patients with HCCs with a largest diameter of more than 5 cm with three or fewer lesions and no portal vein tumor thrombus. The mean maximum tumor diameter was 7.7 cm +/- 2.4. When the tumor was extremely large and had multiple feeding arteries, stepwise chemoembolization sessions at intervals of 3-10 weeks were performed. In addition, extrahepatic collateral supply was identified and embolized. Local therapeutic effects, survival rates, and complications were analyzed. RESULTS: The mean follow-up period was 33.8 months +/- 24.1. One to 13 chemoembolization sessions (mean, 4.0 sessions +/- 3.0) were performed in each patient. Additionally, 62 collateral vessels were embolized in 21 patients, including 22 vessels in 14 patients at the initial procedure. Early tumor response rate 2-3 months after treatment was 43.3% by Response Evaluation Criteria In Solid Tumors. Complete radiologic response was achieved in 19 patients. Eleven patients died between 4 and 61 months after treatment (mean, 27.2 months +/- 21.8), including four deaths unrelated to hepatic causes. Nineteen patients have survived for 6-103 months (mean, 37.5 months +/- 25.2). Overall and progression free-survival rates at 1, 3, and 6 years were 82.3% and 66.0%, 73.9% and 57.6%, and 32.9% and 34.2%, respectively. Three infectious complications developed and were managed by interventions. CONCLUSIONS: Chemoembolization was effective for large HCCs, although there is a risk of infectious complications after the procedure.

Main bile duct stricture occurring after transcatheter arterial chemoembolization for hepatocellular carcinoma.

The purpose of this study was to evaluate the clinical course of main bile duct stricture at the hepatic hilum after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Among 446 consecutive patients with HCC treated by TACE, main bile duct stricture developed in 18 (4.0%). All imaging and laboratory data, treatment course, and outcomes were retrospectively analyzed. All patients had 1 to 2 tumors measuring 10 to 100 mm in diameter (mean ± SD 24.5 ± 5.4 mm) near the hepatic hilum fed by the caudate arterial branch (A1) and/or medial segmental artery (A4) of the liver. During the TACE procedure that caused bile duct injury, A1 was embolized in 8, A4 was embolized in 5, and both were embolized in 5 patients. Nine patients (50.0%) had a history of TACE in either A1 or A4. Iodized oil accumulation in the bile duct wall was seen in all patients on computed tomography obtained 1 week later. Bile duct dilatation caused by main bile duct stricture developed in both lobes (n = 9), in the right lobe (n = 3), in the left lobe (n = 4), in segment (S) 2 (n = 1), and in S3 (n = 1). Serum levels of alkaline phosphatase and γ-glutamyltranspeptidase increased in 13 patients. Biloma requiring drainage developed in 2 patients; jaundice developed in 4 patients; and metallic stents were placed in 3 patients. Complications after additional TACE sessions, including biloma (n = 3) and/or jaundice (n = 5), occurred in 7 patients and were treated by additional intervention, including metallic stent placement in 2 patients. After initial TACE of A1 and/or A4, 8 patients (44.4%), including 5 with uncontrollable jaundice or cholangitis, died at 37.9 ± 34.9 months after TACE, and 10 (55.6%) have survived for 38.4 ± 37.9 months. Selective TACE of A1 and/or A4 carries a risk of main bile duct stricture at the hepatic hilum. Biloma and jaundice are serious complications associated with bile duct strictures.

The march of extrahepatic collaterals: analysis of blood supply to hepatocellular carcinoma located in the bare area of the liver after chemoembolization.

The purpose of this study was to evaluate changes in vascular supply to hepatocellular carcinoma (HCC) located in the bare area of the liver in patients who were mainly treated with chemoembolization. Twenty-six patients with HCC showing a mean diameter of 3.1 +/- 1.4 cm (mean +/- standard deviation) were mainly treated with chemoembolization. All patients underwent 2.7 +/- 2.3 chemoembolization sessions over 40.1 +/- 25.2 months. Tumor feeding branches demonstrated in each chemoembolization session were retrospectively evaluated. Initially, 18 tumors (59.2%) were supplied by the hepatic artery (H) and 8 (30.8%) by both the hepatic and the extrahepatic arteries (H + C). Fourteen tumors (53.8%) recurred at the posterior aspect of the tumor and were supplied by H (n = 4), H + C (n = 5), and extrahepatic collaterals (C) (n = 5). Several tumors recurred despite repeated chemoembolization, and these were supplied by H (n = 1), H + C (n = 7), and C (n = 2) at the second recurrence, by H (n = 1), H + C (n = 2), and C (n = 3) at the third, by H + C (n = 2) and C (n = 2) at the fourth, by H + C (n = 2) and C (n = 2) at the fifth, and by H (n = 1) and C (n = 1) at the sixth. One tumor was supplied by H at the seventh and by H + C at the eighth recurrence. As the number of local recurrences increased, the feeding vessel shifted from H to C. Especially, the right inferior phrenic artery (IPA) and renal capsular artery (RCA) supplied the tumor early, while the small right RCAs, adrenal arteries, and intercostal and lumbar artery supplied late recurrences in turns. In conclusion, HCCs located in the bare area are frequently supplied by extrahepatic vessels initially, while recurrence after chemoembolization is mainly due to extrahepatic blood supply. The right IPA and RCA are common feeding vessels demonstrated early, while other extrahepatic collateral supply from the retroperitoneal circulation occurs in turns during the later course.

Sloughing of intraductal tumor thrombus of hepatocellular carcinoma after transcatheter arterial chemoembolization.

Transcatheter arterial chemoembolization (TACE) is effective for hepatocellular carcinoma (HCC) with intrabile duct thrombus. After TACE, intraductal tumor thrombi occasionally detach from the intrahepatic tumor and drop into the bottom of the common bile duct, causing clinical symptoms similar to the impaction of choledocholithiasis. The investigators describe three cases of sloughing of HCC intraductal tumor thrombi after selective TACE. In each of the three cases, the necrotic tumor cast was successfully removed endoscopically, and the patient's symptoms were dramatically improved. Two patients survived without recurrence of the intraductal tumor thrombus for 8 and 11 months after TACE, respectively.

Hepatocellular carcinoma supplied by the right lumbar artery.

This study evaluated the clinical features of hepatocellular carcinoma (HCC) supplied by the right lumbar artery. Eleven patients with HCC supplied by the right lumbar artery were treated with chemoembolization. The patients' medical records were retrospectively analyzed. All patients underwent 6.7 +/- 3.7 (mean +/- SD) chemoembolization sessions, and the hepatic arterial branches were noted as being attenuated. The right inferior phrenic artery (IPA) was also embolized in 10 patients. The interval between initial chemoembolization and chemoembolization of the lumbar artery supply was 53.2 +/- 26.9 months. Mean tumor diameter was 3.1 +/- 2.4 cm and was located at the surface of S7 and S6. The feeding-branch arose proximal to the bifurcation of the dorsal ramus and muscular branches (n = 8) or from the muscular branches (n = 3) of the right first (n = 10) or second lumbar artery (n = 1). The anterior spinal artery originated from the tumor-feeding lumbar artery in one patient. All feeders were selected, and embolization was performed after injection of iodized oil and anticancer drugs (n = 10) or gelatin sponge alone in a patient with anterior spinal artery branching (n = 1). Eight patients died from tumor progression 10.1 +/- 4.6 months later, and two patients survived 2 and 26 months, respectively. The remaining patient died of bone metastases after 32 months despite liver transplantation 10 months after chemoembolization. The right lumbar artery supplies HCC located in the bare area of the liver, especially in patients who undergo repeated chemoembolization, including chemoembolization by way of the right IPA. Chemoembolization by way of the right lumbar artery may be safe when the feeder is well selected.

Usefulness of cone-beam computed tomography during ultraselective transcatheter arterial chemoembolization for small hepatocellular carcinomas that cannot be demonstrated on angiography.

This study evaluated the usefulness of cone-beam computed tomography (CBCT) during ultraselective transcatheter arterial chemoembolization (TACE) for hepatocellular carcinomas (HCC) that could not be demonstrated on angiography. Twenty-eight patients with 33 angiographically occult tumors (mean diameter 1.3 +/- 0.3 cm) were enrolled in the study. The ability of CBCT during arterial portography (CBCTAP), during hepatic arteriography (CBCTHA), and after iodized oil injection (LipCBCT) to detect HCC lesions was retrospectively analyzed. The technical success of TACE was divided into three grades: complete (the embolized area included the entire tumor with at least a 5-mm wide margin), adequate (the embolized area included the entire tumor but without a 5-mm wide margin in parts), and incomplete (the embolized area did not include the entire tumor) according to computed axial tomographic (CAT) images obtained 1 week after TACE. Local tumor progression was also evaluated. CBCTAP, CBCTHA, and LipCBCT detected HCC lesions in 93.9% (31 of 33), 96.7% (29 of 30), and 100% (29 of 29) of patients, respectively. A single branch was embolized in 28 tumors, and 2 branches were embolized in five tumors. Twenty-seven tumors (81.8%) were classed as complete, and 6 (18.2%) were classed as adequate. None of the tumors were classed as incomplete. Twenty-five tumors (75.8%) had not recurred during 12.0 +/- 6.2 months. Eight tumors (24.2%), 5 (18.5%) of 27 complete success and 3 (50%) of 6 adequate success, recurred during 10.1 +/- 6.2 months. CBCT during TACE is useful in detecting and treating small HCC lesions that cannot not be demonstrated on angiography.

Influence of functional appliances on masticatory muscle activity.

The purpose of the present study was to investigate the influence of an activator appliance and a spring active appliance on masticatory muscle activity by means of electromyography (EMG). Twelve adult males with good general health were recruited as subjects. Three functional appliances were used in each subject for long-period EMG recording during daytime and sleep and short-time EMG recording during voluntary biting. Following findings were obtained. (1) The activity of all muscles was greater during biting than during daytime and sleep, (2) the muscle activities tended to increase in the digastric muscle and to decrease in the temporal muscle with activators under all conditions, and (3) the temporalis-masseter ratios became lower with the biting use of appliances. Therefore, this study suggests that functional appliances should be used during sleep and during the day in combination with voluntary biting to achieve adaptation and development of the masticatory muscles.