15 - Testure Analysis in Three Dimensions as a Cue to Medical Diagnosis

Abstract

There has been a proliferation of sensors that create three-dimensional (3D) data, particularly in medicine. These sensors either operate in the plane, creating multiple slices that can be treated as volume data if they are dense enough, or operate in 3D space directly, such as new positron emission tomography (PET) techniques that reconstruct volume data by considering out-of-plane coincident events. Generally, volume data are analyzed and viewed as a set of two-dimensional (2D) images. However, even when sufficient volume data is available, analysis and visualization of volume data are typically guided by the limited abilities of human perception, which is not suited well to process volume data. As a result, a large part of the information content of the data may be ignored. Computerized analysis offers the exciting option of escaping from the anthropocentric description of images, and go beyond the limitations of the human visual and cognitive system. This chapter presents some techniques appropriate for the texture analysis of volume data in the context of medical applications and also demonstrates two different approaches for analyzing 3D textures. The microstructural features that can be calculated this way offer a totally new perspective to the clinician, and the exciting possibility of identifying new descriptions and new indicators that may prove valuable in the diagnosis and prognosis of various conditions. This method effectively projects all gradients on all directions and adds their square magnitudes. This chapter also presents the potential that 3D texture measures have for diagnosing pathology, quantifying its severity, and quantifying its change with time.