Joji Urata

Percutaneous microwave coagulation therapy in liver tumors

Purpose: Percutaneous microwave coagulation therapy (PMCT) is an interventional alternative for inoperable malignant liver tumors. in this paper, we report the results of our 3-year experience of PMCT in order to establish suitable indications for this treatmentMaterial and Methods: We studied a total of 27 inoperable liver tumors in 24 patients. Histology of the tumors showed 20 hepatocellular carcinomas (HCCs) (13 well differentiated, 4 moderately differentiated, and 3 poorly differentiated) and 7 metastases. These tumors were treated by PMCT and were followed for 4–40 months (average 18 months). Under US guidance, the tumors were coagulated by microwaves emitted from an electrode. the changes of tumor size after PMCT were evaluated by CT. When the tumors disappeared or were reduced in size after treatment, PMCT was regarded as effective. Complications from PMCT were also evaluated. the patient survival rate was obtained by means of the Kaplan-Meier methodResults: in tumors of 30 mm or less, treatment r...

Prognostic factors in the treatment of hepatocellular carcinoma with transcatheter arterial embolization and arterial infusion

From January 1986 to December 1988, a prospective trial of transcatheter arterial treatment was carried out for hepatocellular carcinoma (HCC). Two hundred seventy‐five patients were included. Okudas staging system was employed. Patients with Stage I and II HCC were treated by transcatheter arterial embolization (TAE) with a gelatin sponge containing an anti‐cancer agent (protocol 1a); a gelatin sponge and iodized oil mixed with an anti‐cancer agent (protocol 1b); or iodized oil mixed with an anti‐cancer agent (protocol 2). Patients with Stage III HCC were treated with iodized oil with anti‐cancer agent (protocol 2). As an exception, patients with an unsuccessful superselective catheterization into the proper hepatic artery by Seldinger technique or obstruction of the main trunk of the portal vein were treated with percutaneous transcatheter arterial infusion into the common hepatic artery regardless of stage (protocol 3). Tumor type and extension, area of tumor involvement, portal vein involvement, method of treatment, and presence of ascites and icterus were found to be the significant factors for an initial response to therapy. Treatment method was the most important factor. Respective survival rates at 1 and 2 years were 70.9% and 55.3% for protocol 1a; 62.3% and 43.8% for protocol 1b; 37.8% and 18.3% for protocol 2; and 16.5% and 0% for protocol 3. Many factors proved to significantly influenced prognosis; however, tumor type had the most important prognostic significance followed by AFP value, ascites, treatment protocol, and area of tumor involvement.

Percutaneous microwave coagulation therapy in liver tumors: A 3-year experience

Purpose: Percutaneous microwave coagulation therapy (PMCT) is an interventional alternative for inoperable malignant liver tumors. in this paper, we report the results of our 3-year experience of PMCT in order to establish suitable indications for this treatment. Material and Methods: We studied a total of 27 inoperable liver tumors in 24 patients. Histology of the tumors showed 20 hepatocellular carcinomas (HCCs) (13 well differentiated, 4 moderately differentiated, and 3 poorly differentiated) and 7 metastases. These tumors were treated by PMCT and were followed for 4–40 months (average 18 months). Under US guidance, the tumors were coagulated by microwaves emitted from an electrode. the changes of tumor size after PMCT were evaluated by CT. When the tumors disappeared or were reduced in size after treatment, PMCT was regarded as effective. Complications from PMCT were also evaluated. the patient survival rate was obtained by means of the Kaplan-Meier method. Results: in tumors of 30 mm or less, treatment response was obtained in 70% of cases, while 55% of tumors larger than 30 mm responded. the tumor became smaller or disappeared in 85% of the well differentiated HCCs, and in 25% of the moderately differentiated HCCs, but none of the poorly differentiated HCCs responded. in metastatic tumors, PMCT was effective in 57% of cases, Slight pain (24%), fever (20%) and subcutaneous hematoma (8%) were experienced immediately after PMCT. in 2 poorly differentiated HCCs, needle tract seeding was observed. No case of liver dysfunction was seen after PMCT. the overall survival rate was 83.1% at 1 year and 68.7% at 2 years. Conclusion: Good therapeutic results were achieved with PMCT in lesions of 30 mm or less, and in well differentiated HCCs.

The effects of transjugular intrahepatic portosystemic shunt on portal hypertensive gastropathy

In addition to variceal bleeding, haematemesis may occur due to haemorrhagic gastritis in patients with portal hypertension. This has been known as portal hypertensive gastropathy (PHG). We have evaluated the effects of the transjugular intrahepatic portosystemic shunt (TIPS) on portal venous pressure (PVP) and endoscopic gastric mucosal changes observed in patients with portal hypertension. We performed TIPS in 12 patients with complications due to portal hypertension as follows: variceal bleeding in nine patients (bleeding from oesophageal varices in seven and gastric varices in two), refractory ascites in three and haemorrhage from severe PHG in one. Endoscopic examinations were performed before and after TIPS for all patients. Changes of PVP and gastric mucosal findings on endoscopy were analysed. Before TIPS, PHG was seen in 10 patients. Portal venous pressure decreased from an average of 25.1 ± 8.8 to 17.1 ± 6.2 mmHg after TIPS (P < 0.005). On endoscopy, PHG improved in nine of 10 patients. Oesophagogastric varices improved in eight of 11 patients. In one patient with massive haematemesis, haemorrhage from severe PHG completely stopped after TIPS. Because TIPS effectively reduced PVP, this procedure appeared to be effective for the treatment of uncontrollable PHG.

Clinical evaluation of aortic diseases using nonenhanced MRA with ECG-triggered 3D half-Fourier FSE.

The efficacy of the nonenhanced magnetic resonance angiography (MRA) technique known as fresh‐blood imaging (FBI), using electrocardiograph (ECG)‐triggered 3D half‐Fourier fast spin‐echo (FSE), was evaluated for the detection and characterization of aortic diseases. Seventy‐five consecutive patients with aortic disease underwent the FBI examination on a 1.5‐T clinical imager. The results showed that the FBI technique permits clear visualization of aortic diseases, and the vessel branches and their relationship, which provides valuable information. Therefore, the nonenhanced FBI technique is appropriate to use for screening purposes. J. Magn. Reson. Imaging 2001;14:113–120.

Cardiac 16-MDCT for anatomic and functional analysis: Assessment of a biphasic contrast injection protocol

OBJECTIVE The purpose of this study was to determine the optimal contrast injection protocol for clear delineation of the endocardial and epicardial contours and coronary vessels in anatomic and functional imaging with cardiac 16-MDCT. SUBJECTS AND METHODS Thirty-eight patients were allocated to three groups according to contrast injection protocol: a long-duration biphasic protocol in which diluted contrast material was used in the latter phase (protocol A, 13 patients); a uniphasic protocol with saline flush (protocol B, 12 patients); a uniphasic protocol without a flush (protocol C, 13 patients). Six regions of interest were drawn within the left ventricle (LV), right ventricle (RV), and interventricular septum along the z-axis. Mean ventricular attenuation, mean difference between maximum and minimum ventricular attenuation, and ventricular-myocardial contrast-to-noise ratio (CNR) were calculated. Attenuation and visualization of the coronary vessels also were compared. RESULTS The difference between maximum and minimum RV attenuation was significantly smaller in group A (58.1 H) than in groups B (179.5 H) and C (157.0 H). RV-myocardial CNR was significantly higher in group A (9.0) than in group B (5.5). The mean LV attenuation, difference between maximum and minimum LV attenuation, and LV-myocardial CNR were not significantly different among three groups. In protocol A, both endocardial and epicardial contours were clearly delineated, and cardiac functional analysis was feasible in all cases. Average attenuation and visualization of the coronary vessels were not significantly different among groups. The diagnostic accuracies in detection of coronary stenosis were 92%, 93%, and 91%, respectively, for protocols A, B, and C. CONCLUSION The long-duration contrast injection protocol with diluted contrast material is optimal for assessing the coronary vessels and cardiac function.

16-MDCT aortography with a low-dose contrast material protocol.

OBJECTIVE The objective of our study was to evaluate whether a low-dose contrast material (CM) protocol with a saline flush might provide sufficient contrast enhancement in aortoiliac 16-MDCT angiography. SUBJECTS AND METHODS Forty-five patients were divided into two groups on the basis of the CM (300 mg I/mL) administration protocol: group 1 (23 patients) received 100 mL of CM at 3.0 mL/sec; and group 2 (22 patients), 50 mL of CM at 3.0 mL/sec followed by a 20-mL saline flush at 3.0 mL/sec. All patients underwent 16-MDCT angiography of the entire aortoiliac region. Seven regions of interest (ROIs) were drawn from the ascending aorta (ROI 1) to the external iliac artery (ROI 7). Quantitative analysis was performed by calculating the mean aortoiliac attenuation and the mean difference between the maximum and minimum attenuation values. Vascular enhancement of the renal arteries was visually assessed using 2D and 3D postprocessing techniques. RESULTS The mean aortoiliac attenuation in group 1 was 314.3 +/- 45.9 H and that in group 2 was 306.1 +/- 35.0 H. The difference was not statistically significant. Adequate mean aortoiliac attenuation was achieved in 95.7% (22/23) and 95.5% (21/22) of patients in groups 1 and 2, respectively. The difference was not statistically significant. The mean difference between the maximum and minimum attenuation values was significantly smaller in group 1 (41.3 +/- 16.8 H) than in group 2 (57.2 +/- 25.3 H). The renal arteries were assessable in all patients in both groups. CONCLUSION This protocol of 50 mL of CM with a saline flush provides attenuation comparable to that obtained with the 100 mL of CM in aortoiliac 16-MDCT angiography.

Acute adrenal hemorrhage after blunt trauma

ObjectiveTo determine the appropriate management of adrenal hemorrhage in patients with severe chest and upper abdominal blunt trauma.Materials and MethodsWe reviewed 7 patients who suffered from severe traumatic adrenal hemorrhage after a traffic accident (n = 4) or fall (n = 3). Contrast-enhanced CT images were analyzed for multi-organ traumatic injury, hematoma size, extravasation, and pseudoaneurysm formation. We also report their management including transarterial embolization (TAE) and follow-up findings.ResultsAll 7 patients manifested multi-organ traumatic injury and hemothorax; 5 also had rib fractures, 5 had abdominal organ injuries (liver, n = 3; kidneys, n = 2; pancreas, n = 1); 2 had dorsal fractures, and 1 had a traumatic aortic aneurysm. On CT images, unilateral right adrenal hematomas ranging from 20 to 50 mm (mean 26 mm) in length and from 15 to 50 mm (mean 23 mm) in width were seen. In 6 patients these were localized, and they were followed without any intervention. The other patient had a massive hematoma with pseudoaneurysm and extravasation, who subsequently received TAE. At 3-month follow-up all patients were doing well.ConclusionInformation regarding the size of the hematoma and the presence of extravasation helps to select the appropriate management of patients with traumatic adrenal hemorrhage. TAE appears to be useful for treating patients with massive adrenal hemorrhage.

Prognostic factors in liver metastases after transcatheter arterial embolization or arterial infusion.

From January 1986 to December 1988, 85 patients (55 men and 30 women, mean age 59 years) with metastatic liver tumors were treated with hepatic artery embolization (TAE) or infusion (HAI). Sixty-eight patients with successful catheterization were treated with TAE using iodized oil (Lipiodol) mixed with anticancer agent (ACA). In 12 of 68 patients with hypervascular tumors gelatin sponge was added. Patients with unsuccessful catheterization were treated with hepatic artery infusion of ACA. Forty-three patients received oral chemotherapy following TAE or HAI. Overall, the 6-month, and 1- and 2-year survival rates were 69.5, 31.8 and 4.1 per cent, respectively (mean 233 days). A univariate analysis of prognostic factors showed that number of metastases, stage, treatment times and oral chemotherapy were all significant factors (p<0.05). Ascites, jaundice, percentage of hepatic replacement and treatment protocol also had some influence (p<0.1). Sex, age, primary site, elevation of tumor markers, other metastatic lesions, portal vein involvement and difference in anticancer agent had no prognostic significance. A multivariate analysis using Coxs proportional hazard model revealed that the number of treatments had the most important prognostic significance, followed by oral chemotherapy, stage and percentage of hepatic replacement.

Detection of flat colorectal polyps at screening CT colonography in comparison with conventional polypoid lesions

Background Although the screening of small, flat polyps is clinically important, the role of CT colonography (CTC) screening in their detection has not been thoroughly investigated. Purpose To evaluate the detection capability and usefulness of CTC in the screening of flat and polypoid lesions by comparing CTC with optic colonoscopy findings as the gold standard. Material and Methods We evaluated the CTC detection capability for flat colorectal polyps with a flat surface and a height not exceeding 3 mm (n = 42) by comparing to conventional polypoid lesions (n = 418) according to the polyp diameter. Four types of reconstruction images including multiplanar reconstruction, volume rendering, virtual gross pathology, and virtual endoscopic images were used for visual analysis. We compared the abilities of the four reconstructions for polyp visualization. Results Detection sensitivity for flat polyps was 31.3%, 44.4%, and 87.5% for lesions measuring 2–3 mm, 4–5 mm, and ≥6 mm, respectively; the corresponding sensitivity for polypoid lesions was 47.6%, 79.0%, and 91.7%. The overall sensitivity for flat lesions (47.6%) was significantly lower than polypoid lesions (64.1%). Virtual endoscopic imaging showed best visualization among the four reconstructions. Colon cancers were detected in eight patients by optic colonoscopy, and CTC detected colon cancers in all eight patients. Conclusion CTC using 64-row multidetector CT is useful for colon cancer screening to detect colorectal polyps while the detection of small, flat lesions is still challenging.