This report describes an in-stent restenosis of the infrarenal aorta in a patient with Takayasu's arteritis in a nonactive state. A 10-mm-diameter Wallstent had been deployed 42 months previously. The stented restenosed segment was replaced by a surgical graft. Histopathological examination of the excised aortic segment showed a thin layer of fibrocellular neointima and massive organized and calcified thrombus. To our knowledge, this is the first histopathological report of a late in-stent restenosis of the abdominal aorta in Takayasu's arteritis.

Adult↗

PubMedDate not supplied

A system for computer-assisted design of stent-grafts for aortic aneurysms using 3-D morphological models.

A three-dimensional model was constructed from helical CT images for abdominal aortic aneurysm (AAA) and thoracic aortic aneurysm (TAA). A stent-graft was designed and positioned endoluminally on the computer. One hundred and nine stent-grafts for 101 patients were designed by this method and deployed well in all patients. The design time was reduced from 4 to 0.5 hr.

Adult↗

PubMedDate not supplied

Activation of CCK-B receptors elevates cytosolic Ca2+ levels in a pituitary cell line.

Cytosolic Ca2+ levels ([Ca2+]i) in GH3 cells, a rat anterior pituitary tumor cell line, were monitored with fura-2 by fluorescence measurements. Cholecystokinin octapeptide (CCK-8) produced a transient elevation of [Ca2+]i. The elevation of [Ca2+]i by CCK-8 was inhibited by L-365,260, but not by devazepide. It was still observed when extracellular Ca2+ was eliminated, indicating that CCK-8 mobilizes Ca2+ from intracellular storage sites after interaction with CCK-B receptors. Cholecystokinin octapeptide increased the turnover of phosphatidylinositol, but it did not affect cyclic AMP levels. A possible involvement of phosphatidylinositol breakdown and calcium mobilization in the transduction system of CCK-B receptors in GH3 cells is suggested.

Animals↗

PubMedDate not supplied

GH3 cells, an anterior pituitary cell line, express CCK-B receptors.

We found that GH3 cells, a rat anterior pituitary tumor cell line, expressed a single class of high-affinity binding sites for radiolabeled cholecystokinin octapeptide (CCK-8) with a Kd of 48 pM. The binding sites had high affinity for CCK-8, CCK-4, gastrin I, and L-365,260 (CCK-B antagonist), and had low affinity for devazepide (CCK-A antagonist), indicating that the binding sites are CCK-B receptors. GTP and its stable analogues inhibited radiolabeled CCK-8 binding to GH3 cell membranes, suggesting a coupling of CCK-B receptors to a G-protein.

Animals↗

PubMedDate not supplied

A pitfall in ultrafast CT scanning for the detection of left atrial thrombi.

We studied 41 patients with mitral stenosis by ultrafast CT (UFCT) and transesophageal echocardiography to detect left atrial thrombi. Cardiac UFCT was performed twice after contrast medium injection to obtain early (during injection lasting 40-60 s) and late (approximately 5 min after beginning injection) phase images. There were 10 patients (24%) in whom a filling defect detected in the early phase disappeared in the late phase. The site of filling defects was the left atrial appendage in nine patients and the left atrium in one patient. All of the filling defects were in the ventral side of the left atrium. Furthermore, all of those patients had chronic atrial fibrillation. Transesophageal echocardiography revealed no thrombus in the area of the filling defect in the early phase. We believe that blood stasis existed in those patients. This finding leads to a false-positive result when only early phase images are obtained. The diagnosis of thrombi should be made only when a filling defect is observed in both phases. Late phase scanning is necessary in the diagnosis of left atrial thrombi.

Adult↗

PubMedDate not supplied

Quantitative evaluation of mitral regurgitation with ultrafast CT.

OBJECTIVE: To quantify cardiac valvular regurgitation, ultrafast CT was performed in 44 patients (including 27 patients with mitral regurgitation). MATERIALS AND METHODS: Stroke volume of the left ventricle was calculated by modified Simpson's rule with cine mode scanning of ultrafast CT, and ventricular output was measured as the product of stroke volume and heart rate. Cardiac output was calculated in the ascending aorta by the formula of the indicator dilution method with flow mode scanning of ultrafast CT. The difference between the left ventricular output and cardiac output was defined as "mitral regurgitant volume." Left ventriculography was also performed at the same time, to estimate the degree of mitral regurgitation according to Sellers' classification. RESULTS: There was significant correlation between regurgitant fraction, standardized regurgitant volume, and grade of mitral regurgitation estimated by left ventriculography. CONCLUSION: CT can measure mitral regurgitant volume by the combination of volumetry and indicator dilution method.

Adolescent↗

PubMedDate not supplied

Myocardial damage in patients with dilated cardiomyopathy: CT evaluation.

OBJECTIVE: The purpose of this study was to evaluate myocardial damage in patients with dilated cardiomyopathy (DCM) by ultrafast CT (UFCT) and estimate the improvement of DCM. MATERIALS AND METHODS: Seventeen patients with DCM were examined with UFCT, cardiac catheterization, left ventriculography (LVG) with manometry, and thallium myocardial scintigraphy (SCINTI). The findings of each examination were compared with each other. Especially, UFCT findings were compared with LV function. RESULTS: Late enhancement, focal wall thinning, and fatty component were detected by UFCT as focal abnormal findings. Left ventricular segments with these findings on UFCT correlated well with asynergy on LVG (p < 0.01) and perfusion defects on SCINTI (p < 0.05). Patients with these findings on UFCT showed significantly lower LV ejection fractions (p < 0.05), higher LV end-diastolic pressure (p < 0.05), and a higher incidence of ventricular tachycardia (p < 0.05). CONCLUSION: The focal myocardial abnormalities in DCM patients were well depicted with UFCT. Ultrafast CT was useful in estimating the severity of DCM and classifying the DCM patients.

Adolescent↗

PubMedDate not supplied

Popliteal artery entrapment syndrome: aberrant origin of gastrocnemius muscle shown by 3D CT.

PURPOSE: The purpose of this report is to evaluate the usefulness of 3D CT in the diagnosis of popliteal artery entrapment (PAE) syndrome. METHOD: Three patients (three men, 22-70 years old) with suspected PAE syndrome were examined using helical CT. 3D images were reconstructed to evaluate the relationship between the popliteal artery and the gastrocnemius muscle. 3D arteriograms were simultaneously reconstructed. RESULTS: One patient had unilateral type 3 PAE syndrome. Bilateral PAE syndrome was seen in the other two cases: One had bilateral type 2 anomalies and the other had type 3 on the left and type 2 on the right. In all three cases the anomalous origin of the medial head of the gastrocnemius muscle and its relationship to popliteal artery were clearly visualized by 3D CT. In addition, CT arteriography could detect occlusion, deviation, or stenosis of the popliteal arteries. CONCLUSION: 3D CT is useful in the diagnosis and management of PAE syndrome.

Adult↗

PubMedDate not supplied

Coronary artery anomalies with a shunt: evaluation with electron-beam CT.

PURPOSE: Our goal was to evaluate the role of electron-beam CT (EBT) in the diagnosis of patients with coronary artery anomalies with a shunt. METHOD: We performed EBT in seven patients with coronary artery anomalies with a shunt. Four cases were coronary artery fistula (CAF) and three were an anomalous origin of the left coronary artery from the pulmonary artery (ALCA from PA). Serial single volume mode scanning was performed at end-diastole to evaluate the anatomical course of the anomalous coronary arteries. Cine mode scanning was done in all but one to examine the ventricular wall motion and volumetrics. RESULTS: EBT could detect the course and drainage sites of all CAFs and ALCAs from PA. Cine mode scanning revealed reduced wall motion in one case with CAF and two cases with ALCA from PA. CONCLUSION: EBT serves a useful role in the assessment of coronary artery anomalies with a shunt.

Adult↗

PubMedDate not supplied

MRA of the Adamkiewicz artery: a preoperative study for thoracic aortic aneurysm.

PURPOSE: The purpose of this work was to investigate the ability of MR angiography (MRA) to visualize the Adamkiewicz artery (AKA) as a preoperative study of thoracic aortic aneurysm to prevent ischemic injury of the spinal cord. METHOD: Twenty-six patients scheduled for surgical or endovascular stent-graft repair of thoracic aortic aneurysm were studied with a three-dimensional contrast MRA. Data acquisition was repeated two times following injection of Gd-DTPA. Source images were processed with multiplanar reconstruction and maximum intensity projection. RESULTS: The AKA was identified in 69% (18/26). In three patients, selective angiography of the intercostal artery confirmed the AKA at the same level and side predicted by MRA. The anterior spinal artery and the anterior medullary vein were observed in 50% (13/26) and 65% (17/26), respectively. CONCLUSION: Contrast MRA is a promising technique to visualize the AKA noninvasively as a preoperative evaluation of thoracic aortic aneurysms.

Adult↗

PubMedDate not supplied

Effect of chronic middle cerebral artery stenosis on the local cerebral hemodynamics.

In 36 patients with angiographically proven middle cerebral artery (MCA) stenosis, local cerebral hemodynamics were studied employing angiography, 133Xe inhalation regional cerebral blood flow (rCBF) measurements and CT scans. They had transient ischemic attacks in 8 and completed stroke in 28. The patients with less than 50% stenosis (n = 16) had no hemodynamic abnormality in angiographical and rCBF examinations. The infarction in this group was small and located in the basal ganglia area. The patients with 50 to 74% stenosis (n = 9) often revealed a delayed filling of MCA branches in the angiography, however, they showed no significant rCBF reduction. The infarction in this group was also small and located in the basal ganglia area. The patients with 75 to 99% stenosis (n = 11) exhibited a significant flow depression both in angiographical and rCBF examinations. Three of them had large cerebral infarction in the watershed zone or the cerebral cortex. The results of the present study suggest that the hemodynamic effect of MCA stenosis begins to manifest at 50% in grade and becomes apparent at 75%. The danger of hemodynamic crisis as well as the risk of large cerebral infarction may increase when MCA stenosis exceeds 75% in grade.

Adult↗

PubMedDate not supplied

Three-dimensional CT imaging of aneurysm of aberrant right subclavian artery.

We report a case of an aneurysm originating from an aberrant right subclavian artery, which was incidentally found as a compression deformity of the upper esophagus on a barium study in a 46-year-old man. Computed tomography (CT) clearly demonstrated the aneurysm of the aberrant right subclavian artery. In particular, reconstructed three-dimensional CT (3D-CT) was valuable in evaluating the positional relationships between the anomalous vessel with aneurysm and other structures.

Aneurysm↗