Cardiac Computed Tomography Angiography for Left Atrial Appendage Closure.

Atrial fibrillation is prevalent and percutaneous left atrial appendage (LAA) closure is increasingly performed worldwide. This procedure is technically challenging and the success and procedural complexities depend on anatomy of the LAA and surrounding structures. These are readily depicted on cardiac computed tomography angiography (CCTA), which offers unique imaging planes. CCTA allows not only preplanning anatomic LAA assessment, but can also be used to evaluate for pre-existing LAA thrombus, and done postprocedure for surveillance for device-related thrombus, residual leak, and complications. In this article, we review the practical utility of CCTA for LAA closure.

Coronary anomalies encountered in the acute setting: an imaging review.

A broad spectrum of congenital coronary anomalies may be discovered on imaging and sometimes in the emergency setting on computed tomography (CT). Most coronary artery anomalies are of academic interest; however, a minority can cause morbidity and mortality and symptoms such as angina, myocardial infarction, or arrhythmias. These anomalies are usually discovered as an incidental finding on CT examinations as part of the diagnostic workup for other pathology or on dedicated coronary computed tomography angiography (CCTA) as part of the evaluation for a coronary cause of chest pain. The purpose of this pictorial review is to demonstrate the types of coronary anomalies and to enhance the clinicians' understanding of the imaging classifications and clinical implications.

Trauma sonography for use in microgravity.

Sonography is the only medical imaging modality aboard the ISS, and is likely to remain the leading imaging modality in future human spaceflight programs. While trauma sonography (TS) has been well recognized for terrestrial trauma settings, the technique had to be evaluated for suitability in spaceflight prior to adopting it as an operational capability. The authors found the following four-phased evaluative approach applicable to this task: 1) identifying standard or novel terrestrial techniques for potential use in space medicine; 2) developing and testing these techniques with suggested modifications on the ground (1 G) either in clinical settings or in animal models, as appropriate; 3) evaluating and refining the techniques in parabolic flight (0 G); and 4) validating and implementing for clinical use in space. In Phase I of the TS project, expert opinion and literature review suggested TS to be a potential screening tool for trauma in space. In Phase II, animal models were developed and tested in ground studies, and clinical studies were carried out in collaborating trauma centers. In Phase III, animal models were flight-tested in the NASA KC-135 Reduced Gravity Laboratory. Preliminary results of the first three phases demonstrated the potential clinical utility of TS in microgravity. Phase IV studies have begun to address crew training issues, onboard imaging protocols, and data transfer procedures necessary to offer the modified TS technique for space use.