Three‐dimensional imaging is here and now: Time to prove its relevance

Abstract

I cannot help mocking all our unwavering certainties. It is, for example, great fun deliberately to confuse two and three dimensions, the plane and space. . . it is, for example, a pleasure knowingly to mix up two and three dimensionalities, flat and spatial, and to make fun of gravity. M.C. EscherHumankind has survived for millions of years by successfully interacting with a complex three-dimensional environment through three-dimensional vision. Although each eye sees a two-dimensional image, the eyes work in tandem and with more than 10 10 neurons in the visual cortex to reconstruct three-dimensional perception. Our three-dimensional spatial world moves, and we actually live in four dimensions, three of space and one of time.Medicine in general, and cardiology in specific, deals with complex three-dimensional anatomic structures moving in time. Yet despite our powerful three-dimensional visual capabilities, virtually all diagnostic technologies are constrained to two-dimensional images, usually compressing the third spatial dimension by techniques such as flat plate X-rays, requiring experience and expertise to make diagnoses through interpreting subtle shadows that indicate cardiovascular and intrathoracic pathology. Also, the catheterization laboratory relies on two-dimensional fluoroscopic projection images for making diagnoses, and performing intervention on complex coronary artery anatomy.At last these imaging limitations are yielding to exciting technologic developments permitting the cardiologist to interact with the heart and arteries in their full three-dimensionality. A revolution is underway in both interventional cardiac device research ( Fig. 1) and in clinical cardiac imaging (Fig. 2), made possible through immense computational image processing developed by the computer gaming industry.This article is important at several levels. It first implicitly questions whether coronary artery visualization in three dimensions is relevant. Although we can now perform three-dimensional imaging, evidence of relevance and utility is lacking. The author tested the relevance question and found a positive answer, concluding that three-dimensional visualization in stenting changed therapeutic decisions from what was planned based on traditional fluoroscopic data. This conclusion is not surprising given the complexity of coronary artery anatomy. It is thus an important, early article about the potential relevance for three-dimensional imaging in the catheterization laboratory. Other investigators have asked this question, and have concluded that threedimensional imaging has multiple benefits for understanding coronary anatomy including selecting optimal fluoroscopic visualization angles, and comprehending complex three-dimensional coronary arterial anatomy [1,2]. This cardiovascular imaging revolution requires new knowledge for the interventional cardiologist, including understanding tomographic anatomy, threedimensional reconstruction techniques, and familiarity with three-dimensional software.The article indirect...