CT-fluoroscopy in chest interventional radiology: sliding scale of imaging parameters based on radiation exposure dose and factors increasing radiation exposure dose.

AIM: To verify the usefulness of a sliding scale of imaging parameters to reduce radiation exposure during chest interventional radiology (IR), and to identify factors that increase radiation exposure in order to obtain acceptable computed tomography (CT)-fluoroscopy image quality. MATERIALS AND METHODS: The institutional review board approved this retrospective study, for which the need for informed consent was waived. Interventional radiologists determined the optimal CT-fluoroscopy imaging parameters using the sliding scale based on the radiation exposure dose. The imaging parameters were changed from those generating low radiation (120 kV/10 mA, 1.2 mGy/s) to others generating higher radiation exposure until acceptable image quality was obtained for each procedure. Validation of the imaging parameter sliding scale was done using regression analysis. Factors that increase radiation exposure were identified using multiple regression analysis. RESULTS: In 125 patients, 217 procedures were performed, of which 72 procedures (33.2%, 72/217) were performed with imaging parameters of minimum radiation exposure, but increased radiation exposure was necessary in 145 (66.8%, 145/217). Significant correlation was found between the radiation exposure dose and the percentage achievement of acceptable image quality (R(2) = 0.98). Multivariate regression analysis showed that high body weight (p < 0.0001), long device passage (p < 0.0001), and lesions above the aortic arch (p = 0.04) were significant independent factors increasing radiation exposure. CONCLUSION: Although increased radiation exposure dose might be necessary to obtain acceptable chest CT-fluoroscopy images depending on the patient, lesion, and procedure characteristics, a sliding scale of imaging parameters helps to reduce radiation exposure.

Intractable bronchopleural fistula caused by radiofrequency ablation: endoscopic bronchial occlusion with silicone embolic material.

A 58-year-old man with primary lung cancer underwent lung radiofrequency (RF) ablation. Pneumothorax developed 12 days after lung RF ablation. Despite chest drainage for 1 month, air leakage continued through a bronchopleural fistula. Bronchial occlusion was performed with a silicone embolus, causing cessation of the air leakage.

Case report: Radiofrequency ablation for the treatment of painful isolated wound recurrence after resection of gastric cancer.

A 75-year-old woman underwent radiofrequency (RF) ablation for the treatment of two painful disseminated tumours that appeared and rapidly became larger at the anterior abdominal wound 16 months after she had undergone surgery for gastric cancer. RF ablation was performed under CT-fluoroscopic guidance for both tumours, which measured 5 cm and 3 cm in maximum diameter. Pain was relieved immediately after RF ablation, and both tumours showed significant involution upon physical examination and CT studies. The patient is still alive 15 months after RF ablation, with no evidence of tumour recurrence.

Complications after lung radiofrequency ablation: risk factors for lung inflammation.

This retrospective study was conducted to review the complications of lung radiofrequency (RF) ablation and to clarify the effects of inflammation after lung RF ablation on mortality and morbidity. Complications were evaluated by reviewing medical records on an RF session basis. The C-reactive protein (CRP) value was used as an indicator of inflammation and was measured before and every 1-2 days during the hospital stay after RF ablation. The relationships between CRP values and patient baselines were evaluated to identify factors affecting lung inflammation. 130 patients who underwent 327 lung RF ablation sessions were enrolled in this study. The major complication rate was 18.3% (60/327). Inflammation-related complications such as interstitial pneumonia (n = 2) and aseptic pleuritis (n = 2) developed in four sessions (1.2%). Death occurred in two patients with interstitial pneumonia (0.6%). The mean CRP value increased significantly from 1.3+/-2.6 mg dl(-1) to 3.4+/-5.6 mg dl(-1) (p<0.01) after RF ablation. Large tumour size (>or=2 cm) and previous external-beam radiotherapy were significant factors associated with an increased CRP value in both univariate and multivariate analyses. In conclusion, although the incidence rate is low, fatal lung inflammation may develop after lung RF ablation. Large tumour size and previous external-beam radiotherapy are risk factors for severe lung inflammation.

Predictive factors for distant recurrence of HCV-related hepatocellular carcinoma after radiofrequency ablation combined with chemoembolization.

BACKGROUND: Radiofrequency ablation (RFA) therapy for hepatocellular carcinoma has enabled good local control to be possible. However, after successful local control, distant recurrences frequently occur in the remnant liver. AIM: To identify the predictive factors for distant recurrence after RFA. METHODS: A total of 117 patients with initial non-advanced hepatocellular carcinoma with HCV who underwent RFA in our hospital were selected for this study. After transcatheter chemoembolization, RFA was performed under real-time computed tomography-fluoroscopic guidance. We studied survival rates, local (adjacent to treated tumour) and distant (intrahepatic site distant from the treated tumours) recurrence rates, as well as predictive factors for distant recurrence. RESULTS: After RFA, survival rates were 98.2% and 64.7% at 1 and 5 years, respectively. Child B patients had a significantly worse survival than Child A. Recurrence rates were 2.4% at 5 years for local, and 17.1% and 76.9% at 1 and 5 years, respectively, for distant. The Kaplan-Meier method revealed significantly high recurrence rates in cases with low albumin levels (Alb < 3.5 g/dL), high aspartate aminotransferase levels (AST > 60 IU/L), high alanine aminotransferase levels (ALT > 60 IU/L), low platelet counts (Plt < 10 x 10(4)/microL), and high alpha-fetoprotein levels (AFP > 50 ng/mL). On multivariate analysis, low Alb levels and high AST levels were independent predictive factors for distant recurrence. CONCLUSIONS: Although RFA enables good local control for initial hepatocellular carcinoma, distant recurrence is observed at high rates in HCV patients. Low albumin and high AST levels are predictive factors for distant recurrence.

A long-term follow-up study of radiographically evident degenerative changes in the temporomandibular joint with different conditions of disk displacement.

The purpose of this retrospective study is to assess the relationship between an initial and persisting condition of disk displacement (DD) and the long-term course of radiographically evident degenerative changes of the temporomandibular joint (TMJ). Nineteen patients agreed to a radiographic follow-up examination of 29 joints and were included in this study. The joints were radiographically assessed at the first visit and at least 46 months after the first visit (mean 89.3 months). At the time of the follow-up, all subjects had a good clinical course after a favorable response to the treatments. There were significant relationships between the initial diagnosis of DD and the interval change in the morphology of the articular eminence. The articular eminence became flattened or deformed only in the joints with persistent DD without reduction. And there was a tendency that the condyle became smaller in the joints initially with permanent DD and in the joints which show a progression in the disk-condylar relationship. The results of this study suggested that, in the joints with persisting non-reducing disk displacement, flattening and deformation of the articular eminence and regression of the condylar size were likely to happen even after symptoms and signs of TMJ disorders were resolved or reduced.

A case of monoclonal immunoglobulin light- and heavy-chain deposition disease exhibiting atypical deposition with fibrillary structures, successfully treated with chemotherapy.

We report a case of light and heavy chain deposition disease (LHCDD), a rather rare monoclonal immunoglobulin deposition disease (MIDD) with successful therapeutic effect. A 58-year-old woman suffered from proteinuria and renal insufficiency (serum creatinine 1.0 mg/dl, creatinine clearance 49.2 ml/min) in February 2003. In serum and urine samples, monoclonal IgG-kappa was detected. A bone marrow aspiration showed a slightly hypocellular marrow and plasma cell population was increased to 7.0%. Renal histological findings revealed lobulated glomeruli with nodular lesions on light microscopy, characteristic findings of MIDD. Intense deposition of IgG heavy chains in the linear pattern in the glomerular and tubular basement membranes was observed. Immunohistochemistry revealed both kappa and lambda light chain depositions in glomeruli. Electron-microscopic examination revealed fine granular electron-dense deposits accompanied by microfibrils. Based on these findings, this patient was diagnosed as LHCDD. She received three courses of melphalan and prednisone chemotherapy, resulting in disappearance of proteinuria, prevention of renal functional deterioration and the decrease of monoclonal immunoglobulin. This case clearly demonstrates that the earlier and accurate diagnosis and initiation of chemotherapy at the early stage with serum creatinine level below 4.0 mg/dl are necessary to improve renal and patient outcome.

[Recurrent lung cancer with interstitial pneumonia treated with percutaneous radiofrequency ablation].

We performed computed tomography (CT)-guided percutaneous radiofrequency ablation (RFA) for postoperative recurrent pulmonary metastases developed in a 77-year-old man with interstitial pneumonia. He had received left upper segmentectomy with ND 2a nodal dissection. RFA was safely performed for pulmonary metastases in right S6 and left S6. There was no evidence to suggest any deterioration on interstitial pneumonia, including KL 6 and CT findings. Autopsy revealed residual cancer cells in peripheral lesion in 1 of 2 tumors treated by RFA. Although RFA is palliative, it is a promising treatment for local control of pulmonary malignancy in high-risk patients.

Relationship between alteration of horizontal size and bony morphological change in the mandibular condyle.

OBJECTIVE: To analyse the relationship between horizontal size and morphological changes on the articular surface and the lateral part of the mandibular condyle. METHODS: The study group comprised 139 joints in 88 women aged over 18 years. Horizontal condylar size was measured in the anteroposterior (AP) and mediolateral (ML) dimensions using axial MR images. Bony morphological change on the articular surface (sagittal change) was assessed on the sagittal MR image, and resorption of the lateral part of the condyle (RLC) was assessed on a plane radiograph in the AP projection. RESULTS: There was no significant relationship between horizontal condylar size and sagittal change. However, condyles with RLC were smaller than those without RLC in the ML dimension. CONCLUSIONS: The results of this study suggest a possible relationship between decreased horizontal condylar size and RLC. It is also suggested that sagittal bone changes do not influence the horizontal size of the condyle.

Clinical efficacy of brachytherapy combined with external-beam radiotherapy and repeated arterial infusion chemotherapy in patients with unresectable extrahepatic bile duct cancer.

The objective of this study was to evaluate the clinical efficacy of brachytherapy combined with external-beam radiotherapy and repeated arterial infusion chemotherapy in improving stent patency and prognosis in patients with unresectable bile duct cancer as compared with brachytherapy alone. Seventeen patients were treated. Five patients received brachytherapy alone before stent placement. Twelve patients received brachytherapy combined with external-beam radiotherapy (n=5), repeated hepatic arterial infusion chemotherapy using an implanted catheter and port (n=1), or both (n=6). Mean survival was significantly improved in the group that received combined therapy as compared with the group that received brachytherapy alone (16.2 months vs. 4.6 months, p<0.01). Although stent occlusion rates were similar in the two groups (42% vs. 40%), there was a trend towards longer stent patency in the combined therapy group than in the brachytherapy group (22 months vs. 3.6 months, p<0.2). Radiation gastritis necessitating gastrectomy developed in 1 patient who received external-beam radiotherapy at more than 50 Gy. Brachytherapy combined with external-beam radiotherapy and repeated hepatic arterial infusion chemotherapy increases survival compared with brachytherapy alone in patients with unresectable bile duct cancer.

Malignant portal venous obstructions treated by stent placement: significant factors affecting patency.

PURPOSE: To identify factors affecting stent occlusion after stent placement in the portal vein in patients with malignant portal vein invasion. MATERIALS AND METHODS: Forty patients were studied. Twenty-three patients had hepatocellular carcinoma, nine patients had pancreatic cancer, and eight patients had bile duct cancer. Stents were placed in the portal venous system across stenotic (n = 28) or obstructive (n = 12) lesions after percutaneous transhepatic portography. Bare stents were used in 33 patients and covered stents were used in seven patients. Twenty-two variables were analyzed with use of univariate and multivariate analyses to identify significant factors affecting stent occlusion. RESULTS: Stents remained patent during a mean follow-up period of 11.9 months (range, 2-61 mo) in 60% of the patients. Stent occlusion was found in 40% of the patients, with a mean period until occlusion of 3.7 months (range, 0.2-16 mo). In the univariate analysis, the following five factors were significantly associated with a higher probability of stent occlusion: (i) splanchnic vein involvement, (ii) Child-Pugh class C, (iii) obstruction of the portal venous system, (iv) pancreatic cancer, and (v) lack of anticancer treatment after stent placement. In the multivariate analysis, the first three factors were found to have independent value for stent occlusion. CONCLUSIONS: Splanchnic vein involvement, severe hepatic dysfunction, and obstruction of the portal venous system are the most important factors affecting stent occlusion in patients with malignant portal vein invasion.

[Advanced hepatocellular carcinoma--feasibility and clinical impact of high-dose-rate brachytherapy on the treatment of lesions growing into biliary trees, portal veins and the vena cava].

This study was performed to evaluate the feasibility and clinical impact of intraluminal and endovascular high-dose-rate iridium-192 brachytherapy on the treatment of HCC lesions growing into biliary trees, portal veins and the inferior vena cava. HCCs involving biliary trees in 2 patients, the main and/or first-order portal veins in 3 patients, and the inferior vena cava in 2 patients. Brachytherapy was percutaneously performed with a 5F applicator, which was placed adjacent to the lesions. A mean total dose of 23 Gy (range, 5-7 Gy/fr) was irradiated (at a 5 mm radius) to the biliary or the portal venous tumors. A total dose of 10 Gy (5 Gy/fr) was given to the caval tumors. External-beam radiotherapy was combined in 2 patients with caval lesions, stent placement in 2 patients with biliary lesions and hepatic arterial infusion chemotherapy in 5 patients. There was no major complication except hemobilia, which ceased after placing a PTCD tube in the bile duct in one patient. All tumors were significantly reduced in size and remained controlled during the period of patients' survival. Complete tumor necrosis was histologically proved in 2 autopsy cases having biliary lesions. The median survival was 13 months. Intraluminal and endovascular high-dose-rate brachytherapy appears to be a feasible, and effective procedure to treat advanced HCCs invading biliary trees, portal veins and the vena cava.

[Transarterial chemoembolization (TAE) with degradable starch microspheres (DSM) in advanced hepatocellular carcinoma].

This study was undertaken to evaluate the clinical utility of chemoembolization using degradable starch microspheres (DSM), which resolve in a short period in patients with advanced hepatocellular carcinoma (HCC). Twenty-one patients underwent DSM chemoembolization 24 times. After a mixture of iodized oil and epirubicin was injected into the hepatic arteries, the patients were embolized with DSM alone 16 times. In the other 8 times, embolization was done in one hepatic lobe with DSM and in the other hepatic lobe with gelatin sponge (GS). There was no major complication related to chemoembolization. Tumor response (complete, partial, and minor responses) was found in 46% of patients after TAE. Tumor recurrence was found in 64% of responders after a mean period of 2.0 months. The response rate was significantly higher when chemoembolization was performed using both DSM and GS than when it was done with DSM alone (63% vs 37%, p < 0.04). Although the response rate after DSM-TAE is low, its anticancer effect is reinforced when used as an adjuvant therapy of GS-TAE.

[Hepatic intra-arterial infusion chemotherapy using polymer-coated 2.9 Fr implantable catheter-port system--initial experience].

We developed a new 2.9 Fr implantable catheter-port system (reservoir) to perform arterial infusion chemotherapy in patients with unresectable liver tumors. This study was undertaken to evaluate the feasibility of placing this new reservoir system in patients in whom placement of a 5 Fr-reservoir system would seem to be difficult because of severe stricture, tortuosity or angulation of the hepatic artery. A new reservoir system was successfully implanted in 25 patients during 27 sessions. After a side hole was opened, a 2.9 Fr catheter was inserted in the distal hepatic artery or in the gastroduodenal artery in 24 sessions. The catheter tip was then fixed with coils to prevent catheter dislocation. In the other 3 sessions, a 2.9 Fr catheter was inserted without catheter fixation in the replaced right hepatic artery and a small sized collateral artery towards the liver. Arterial infusion chemotherapy was done without any trouble after 20 sessions. Catheter dislocation was found after 2 sessions in which the catheter tip was not fixed or inadequately fixed. Early arterial occlusion was found after placing a 2.9 Fr catheter in the replaced hepatic artery and the small sized-collateral artery after 4 sessions. In conclusion, although sequellae should be evaluated over a long-term period, implantation of a new 2.9 Fr reservoir system is technically feasible and useful in performing arterial infusion chemotherapy.

Fast 3D dynamic MR imaging of the liver with MR SmartPrep: comparison with helical CT in detecting hypervascular hepatocellular carcinoma.

Dynamic magnetic resonance (MR) imaging with SmartPrep was compared with dynamic enhanced helical computed tomography (CT) for the detection of hepatocellular carcinoma (HCC). Thirty patients with 49 HCCs were studied. Arterial-phase MR images using with SmartPrep were significantly superior to arterial-phase CT in detecting small lesions (< or = 2 cm) (85.3% vs. 67.6%, P < .05). In addition, in six recurrent tumors after arterial chemoembolization, dynamic MR imaging with MR SmartPrep technique was superior to helical CT in detecting of recurrent tumors.

Portal venous stent placement in patients with pancreatic and biliary neoplasms invading portal veins and causing portal hypertension: initial experience.

PURPOSE: To evaluate the clinical usefulness of portal venous stent placement in patients with pancreatic or biliary neoplasms invading portal veins and causing portal hypertension. MATERIALS AND METHODS: Thirteen patients underwent portal venous stent placement because of gastrointestinal bleeding (n = 8), risk of gastroesophageal varix rupture (n = 4), ascites (n = 4), thrombocytopenia (n = 3), and/or portal venous thrombosis (n = 3). The main portal vein or both the intrahepatic and main portal veins were invaded in six patients (group A). The main portal vein and splanchnic veins were involved in seven patients (group B). Stents were placed across the stenotic (n = 8) or occluded (n = 5) lesions after percutaneous transhepatic portography. Changes in portal venous pressure, stent patency, and survival were evaluated. RESULTS: Mean portal venous pressure decreased significantly immediately after stent placement, from 24.9 mm Hg +/- 5.9 (SD) to 15.8 mm Hg +/- 4.6 (P <.001). In group A, blood flow through the stent was maintained and the symptoms had subsided at follow-up (mean, 12.5 months). In group B, symptoms were improved in five patients, but the stents were occluded in all but one patient at a mean follow-up of 1.5 months. There was a significant difference in stent patency between the patients with (14%) and those without (100%) splanchnic venous involvement (P <.01). CONCLUSION: Stent placement helped to relieve portal hypertension symptoms. Splanchnic venous involvement was associated with worse stent patency.

Octreotide inhibits pancreatic exocrine secretion and prevents pancreatoenterostomy leakage.

The effects of octreotide, a synthetic somatostatin analogue, were examined in 43 Japanese patients with pylorus-preserving pancreatoduodenectomy. The 43 patients were divided into two groups: 13 patients to whom a daily dose of 100 microg of octreotide was administered continuously and subcutaneously for the first 10 postoperative days (octreotide group); and 30 patients to whom octreotide was not administered (control group). Within 10 postoperative days, pancreatoenterostomy leakage was evident in one (7.7%) of the 13 patients in the octreotide group, but in five (16.7%) of the 30 patients in the control group. The total amount of the pancreatic juice drained externally during the first 10 postoperative days was 848+/-200 ml in the octreotide group and 1152+/-180 ml in the control group. When limited to 20 patients who underwent pancreatoenterostomy with total tube drainage, the amount of pancreatic juice in 10 patients in the octreotide group examined was 796+/-232 ml, which was significantly lower than the 1690+/-334 ml in 10 patients in the control group examined (P < 0.05). Of the 10 patients in the octreotide group, the amount of pancreatic juice during postoperative days 6-10 when octreotide was given was reduced to 382+/-104 ml compared to 445+/-108 ml during postoperative days 11-15 when octreotide was not administered (P < 0.05). These findings suggest that subcutaneous injection of octreotide, 100 microg per day during the first 10 postoperative days, inhibits pancreatic exocrine secretion and decreases pancreatoenterostomy leakage.

Dissociation between the Ca(2+) signal and tube formation induced by vascular endothelial growth factor in bovine aortic endothelial cells.

The correlation between the intracellular Ca(2+) signal and the tube formation in collagen gels induced by vascular endothelial cell growth factor (VEGF) was investigated using cultured bovine aortic endothelial cells. The VEGF-induced sustained elevation of cytosolic Ca(2+) concentration ([Ca(2+)](i)) was similarly inhibited by 10 microM 1-¿beta-[3-(4-methoxyphenyl)propyl]-4-methoxyphenethyl¿-1H-imidazole hydrochloride (SKF 96365) and 10 microM troglitazone. However, 10 microM diltiazem had no effect. The basal tube formation obtained with 1% serum was augmented twofold by 100 ng/ml VEGF. SKF 96365 (0. 1-10 microM) inhibited the VEGF-induced and basal tube formation, while 10 microM troglitazone or 10 microM diltiazem had no effect. The proliferation of endothelial cells was markedly inhibited by SKF 96365 but only slightly by troglitazone and diltiazem. The inhibition of tube formation by three Ca(2+) entry blockers thus correlated with the inhibition of cell proliferation. The [Ca(2+)](i) elevation is thus not a prerequisite for VEGF to induce tube formation.

Characterization of ethylene biosynthesis associated with ripening in banana fruit.

We investigated the characteristics of ethylene biosynthesis associated with ripening in banana (Musa sp. [AAA group, Cavendish subgroup] cv Grand Nain) fruit. MA-ACS1 encoding 1-aminocyclopropane-1-carboxylic acid (ACC) synthase in banana fruit was the gene related to the ripening process and was inducible by exogenous ethylene. At the onset of the climacteric period in naturally ripened fruit, ethylene production increased greatly, with a sharp peak concomitant with an increase in the accumulation of MA-ACS1 mRNA, and then decreased rapidly. At the onset of ripening, the in vivo ACC oxidase activity was enhanced greatly, followed by an immediate and rapid decrease. Expression of the MA-ACO1 gene encoding banana ACC oxidase was detectable at the preclimacteric stage, increased when ripening commenced, and then remained high throughout the later ripening stage despite of a rapid reduction in the ACC oxidase activity. This discrepancy between enzyme activity and gene expression of ACC oxidase could be, at least in part, due to reduced contents of ascorbate and iron, cofactors for the enzyme, during ripening. Addition of these cofactors to the incubation medium greatly stimulated the in vivo ACC oxidase activity during late ripening stages. The results suggest that ethylene production in banana fruit is regulated by transcription of MA-ACS1 until climacteric rise and by reduction of ACC oxidase activity possibly through limited in situ availability of its cofactors once ripening has commenced, which in turn characterizes the sharp peak of ethylene production.