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Jerold S Shinbane

Publications and source records attributed to Jerold S Shinbane.

10 recordsLinked to original sources

MR in patients with pacemakers and ICDs: Defining the issues.

There has been great controversy related to performance of magnetic resonance imaging in patients with pacemakers and implantable cardiac defibrillators. Recent questions have been raised regarding whether contraindications are absolute or relative. Although there are theoretical as well as documented issues relating to device malfunction, data suggest that scanning patients with devices may be feasible when important clinical questions need to be addressed by following strict guidelines. Advanced knowledge and understanding of electrophysiologic as well as magnetic resonance imaging-related issues, and a multidisciplinary, collaborative approach is required to further define the role of MR in patients with pacemakers and implantable cardiac defibrillators.

Artifacts↗

Multiphase contrast medium injection for optimization of computed tomographic coronary angiography.

RATIONALE AND OBJECTIVES: Electron beam angiography is a minimally invasive imaging technique. Adequate vascular opacification throughout the study remains a critical issue for image quality. We hypothesized that vascular image opacification and uniformity of vascular enhancement between slices can be improved using multiphase contrast medium injection protocols. MATERIALS AND METHODS: We enrolled 244 consecutive patients who were randomized to three different injection protocols: single-phase contrast medium injection (Group 1), dual-phase contrast medium injection with each phase at a different injection rate (Group 2), and a three-phase injection with two phases of contrast medium injection followed by a saline injection phase (Group 3). Parameters measured were aortic opacification based on Hounsfield units and uniformity of aortic enhancement at predetermined slices (locations from top [level 1] to base [level 60]). RESULTS: In Group 1, contrast opacification differed across seven predetermined locations (scan levels: 1st versus 60th, P < .05), demonstrating significant nonuniformity. In Group 2, there was more uniform vascular enhancement, with no significant differences between the first 50 slices (P > .05). In Group 3, there was greater uniformity of vascular enhancement and higher mean Hounsfield units value across all 60 images, from the aortic root to the base of the heart (P < .05). CONCLUSIONS: The three-phase injection protocol improved vascular opacification at the base of the heart, as well as uniformity of arterial enhancement throughout the study.

Adult↗

Detection of small vessels with electron beam computed tomographic angiography using 1.5 and 3 mm collimator protocols.

OBJECTIVES: To evaluate the effect of scanner collimation on the ability to detect small cardiac vessels using electron beam CT coronary angiography (EBA). MATERIALS AND METHODS: EBA scans from 40 patients who underwent study on two separate occasions with 3 mm (initial scan) and 1.5 mm (follow-up scan) collimation protocols were analyzed. Vessels of <2 mm in diameter were identified. RESULTS: The 1.5 mm collimation allowed 3-D visualization of 129 vessels<2 mm in diameter, while 3 mm collimation only allowed visualization of 89 vessels (p<0.001). The right coronary artery branches and distal LAD segments though were not displayed satisfactorily in almost half of the 3-D studies with either protocol. CONCLUSIONS: There was significant improvement in detection of small cardiac vessels with a 1.5 mm collimation EBA protocol compared to a 3 mm protocol. Both protocols though were insufficient for reliable visualization of the right coronary artery branches and distal LAD segments.

Coronary Angiography↗

Comparison of coronary artery calcium screening image quality between C-150 and e-Speed electron beam scanners.

RATIONALE AND OBJECTIVE: The newest generation of electron beam tomographic scanner (e-Speed) has increased spatial and temporal resolution compared with the C-150 XP scanner. The aim of this study was to evaluate coronary artery calcium screening image quality between the e-Speed and C-150 scanners (GE Imatron, San Francisco, CA). MATERIALS AND METHODS: Studies from 41 patients (14 women and 27 men) who underwent serial coronary artery calcium screening with the C-150 (first study) and the e-Speed (second study) were analyzed. Individual computed tomography (CT) slices were assessed for coronary artery motion artifacts, and CT Hounsfield units (HU) and noise values (CT HU standard deviation) at 16 discrete cardiac sites were measured and averaged. RESULTS: With the e-Speed scanner, there were significant decreases in right coronary artery motion artifacts compared with the C-150 scanner (0.3% versus 1.8%, P < .001) as well as decreased noise values (24.3 versus 32.0 HU, P < .001). CONCLUSION: Image quality is significantly improved with use of the e-Speed scanner, due to its improved temporal and spatial resolution, compared with the C-150 scanner.

Artifacts↗

Coronary venous imaging with electron beam computed tomographic angiography: three-dimensional mapping and relationship with coronary arteries.

BACKGROUND: The coronary venous system can provide vascular access for diagnostic and therapeutic procedures. Visualization of the coronary veins and their relationship to other cardiac structures may play an important role in facilitating these procedures. We sought to assess the ability of electron beam computed tomographic angiography (EBCTA) to characterize 3-dimensional (3-D) coronary venous anatomy. METHODS: Two hundred thirty-one consecutive EBCTA coronary studies were analyzed. The coronary venous system was mapped and analyzed using 2- and 3-D images with definition of diameter and angulations of branch vessels and distance from CS os. RESULTS: The coronary sinus (CS), great cardiac, middle cardiac, left ventricular (LV) anterior interventricular, LV marginal, LV posterior, left atrial, and right atrial veins were visualized in 100%, 100%, 100%, 100%, 78%, 81%, 6%, and 8% of the studies, respectively, with definition of diameter and angulations of branch vessels and distance from CS os. There was a significant linear correlation between CS diameter and right atrial end systolic volume (R = 0.244, n = 81, P < .05). No significant correlation existed between CS os diameter and other cardiac size or function parameters. The 3-D spatial arrangements between the coronary veins and the coronary arteries in relation to the epicardium were able to be defined, on the basis of the vessel closer to the epicardium in overlapping segments. CONCLUSIONS: EBCTA can provide 3-D visualization of most components of the coronary venous system and definition of the spatial relationships with coronary arteries. EBCTA may potentially serve as a useful noninvasive tool for coronary venous imaging for procedures involving coronary veins, such as resynchronization therapy.

Adult↗

Computed tomographic cardiovascular imaging.

The chapter presents the Cardiac CT for the assessment of cardiovascular pathology with an emphasis on the detection of coronary atherosclerosis. Cardiac CT is a robust technology for the non-invasive assessment for a spectrum of cardiovascular disease processes. This imaging modality can provide assessment of atherosclerotic plaque burden and coronary artery disease risk through coronary calcium scoring. Advances in spatial and temporal resolution, electrocardiographic triggering methodology, and image reconstruction software have helped in the evaluation of coronary artery anatomy and vessel patency, providing the ability to noninvasively diagnose or rule out significant epicardial coronary artery disease. This technique also allows the 3-Dimensional simultaneous imaging of additional cardiac structures including coronary veins, pulmonary veins, atria, ventricles, aorta and thoracic arterial and venous structures, with definition of their spatial relationships for the comprehensive assessment of a variety of cardiovascular disease processes.

Coronary Angiography↗

Methodology for improved detection of coronary stenoses with computed tomographic angiography.

BACKGROUND: Noninvasive angiography is a promising technique for visualization of the coronary lumen; however, current methodologies lead to limited accuracy. We assessed the accuracy of electron beam computed tomographic angiography (EBA) for detection of coronary stenoses, using improved triggering techniques and thinner slice collimation. METHODS: Eighty-six patients with suspected coronary disease were studied with EBA and conventional invasive coronary angiography. Electrocardiographic triggering was performed at a fixed time in end systole to reduce cardiac motion. Thin (1.5 mm) slices were obtained with 1.5 mm table incrementation. In axial (2-dimensional) EBA images and 3-dimensional reconstructions, all coronary arteries and side branches with a diameter of >or=1.5 mm were assessed for the presence of stenoses with >50% diameter reduction. Both EBA and invasive angiographic images were assessed in a blinded manner. RESULTS: In comparison to invasive coronary angiography, EBA correctly classified 49 of 53 patients (92%) as having at least 1 coronary stenosis. Overall, 103 stenoses with >50% diameter reduction were present, and 93 of these lesions were correctly detected by EBA (sensitivity 90%, specificity 93%, positive predictive value 84%, and negative predictive value 96%). Only 5% of vessels could not be assessed, predominantly due to significant calcification. CONCLUSIONS: Thinner slice collimation and end-systolic electrocardiographic triggering improves accuracy and assessment of coronary EBA for the detection of obstructive coronary artery disease, making this study clinically useful in the evaluation of obstructive coronary artery disease.

Coronary Angiography↗

Thebesian valve imaging with electron beam CT angiography: implications for resynchronization therapy.

We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.

Aged↗

Thebesian valve imaging with electron beam CT angiography: implications for resynchronization therapy.

We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.

Aged↗