Spiral CT of the thoracic aorta with 3-D volume rendering: A pictorial review of current applications

Three-dimensional volume rendering of multidetector-row CT data: applicable for emergency radiology

Multidetector-row computed tomography (MD-CT) not only creates new opportunities but also challenges for medical imaging. Isotropic imaging allows in-depth views into anatomy and disease but the concomitant dramatic increase of image data requires new approaches to visualize, analyze and store CT data. The common diagnostic reviewing process slice by slice becomes more and more time consuming as the number of slice increases, while on the other hand CT volume data sets could be used for three-dimensional visualization. These techniques allow for comprehensive interpretation of extent of fracture, amount of dislocation and fragmentation in a three-dimensional highly detailed setting. Further more, using minimal invasive techniques like CT angiography, new opportunities for fast emergency room patient's work up arise. But the most common application is still trauma of the musculoskeletal system as well as face and head. The following is a brief review of recent literature on volume rendering technique and some exemplary applications for the emergency room.

Multiplanar and three-dimensional imaging of the thorax

Although axial images are sufficient for diagnosis in most instances, knowledge of multiplanar imaging techniques is essential to apply them in appropriate circumstances. In particular, appropriately applied multiplanar imaging adds confidence to interpretations and assists surgeons and bronchoscopists in planning procedures. The need for multiplanar imaging must be assessed before performing any study so that the image acquisition parameters allow for suitable reformations.

Parameters affecting bolus geometry in CTA: a review

CT angiography (CTA) is based on acquisition of data during the arterial phase of contrast material passage. CTA needs timing of the contrast bolus, which should be based on accurate knowledge of bolus geometry. Experimental and human studies on bolus geometry and bolus timing in CTA were reviewed. Important parameters of bolus geometry and methods of bolus timing (test bolus and bolus tracking) are described. Recommendations are given for an optimal CTA protocol.

Multidimensional imaging of the thorax: practical applications

Over the past decade, faster CT scan times, thinner collimation, and the development of multirow detectors, coupled with the increasing capability of computers to process large amounts of data in short periods of time, have lead to an expansion in the ability to create diagnostically useful two-dimensional (2D) and three-dimensional (3D) images within the thorax. Applications within the thorax include, but are not limited to, evaluation of pulmonary and systemic vasculature, evaluation of the tracheobronchial tree, and delineation of diffuse lung disease. Pulmonary nodule volume and growth can be more accurately predicted, and represents an improvement in the evaluation of the solitary pulmonary nodule. Multiplanar images increase our understanding of thoracic anatomy and can help to guide bronchoscopic procedures. Because there are strengths and weaknesses to all the reconstruction algorithms, the utility of any given technique is dependent on the clinical question to be answered. For instance, although maximum intensity projection imaging (MIP) is helpful in the evaluation of micronodular lung disease, it is of little value in the diagnosis of aortic dissection. As the ability to generate faster and more precise multidimensional images grow, the demand for such imaging is likely to increase. In this review, the authors discuss the various reconstruction techniques available, followed by a discussion of the clinical applications.

Multi-detector row CT of thoracic disease with emphasis on 3D volume rendering and CT angiography

Multi-detector row computed tomography (CT) with three-dimensional (3D) volume rendering provides a unique perspective on thoracic anatomy and disease. Multi-detector row CT allows shorter acquisition times, greater coverage, and superior image resolution. Three-dimensional volume rendering now permits real-time, interactive modification of relative pixel attenuation in an infinite number of planes and projections. In vascular imaging, this technique provides image quality that equals or surpasses that of conventional angiography. Its use has expanded to aid in diagnosis and surgical planning, often obviating conventional or digital angiography and reducing costs. It is reliable in depicting clot and the pulmonary vasculature and may also be used to evaluate thoracic venous anomalies (eg, pulmonary arteriovenous malformations) and to plan therapy. Airway imaging with multi-detector row CT with 3D volume rendering is particularly useful in the planning and follow-up of stent placement. In diffuse lung disease, this technique can increase nodule detection and help differentiate between small nodules and vessels. It is also helpful in imaging the musculoskeletal system and the thoracic cage. Multi-detector row CT with 3D volume rendering has enhanced the conventional roles of thoracic CT and challenged the supremacy of other imaging modalities. It will likely play a leading role in future radiologic research and practice.