ANALYSIS OF CORTICAL PATTERNS

Analysis of cortical structure is complicated by the complex geometry of the gyral patterns. Image analysis methods are one approach to the problem, and the anatomical detail provided in MR images is ideally suited to these methods. Disruption of normal gyral patterns, alteration of cortical ribbon volumes and simplification of the normal pattern of white matter digitations are features of many pathologies responsible for epilepsy. Many image analysis techniques used in the physical sciences are applicable to these problems. One developing technique is the physical implementation of mathematical morphology (Serra, 1982), which attempts to define images in terms of their shape content. An image is probed with a sequence of filter shapes of different but related sizes, and the response can be represented graphically and numerically. These shape descriptors can define size and shape of features as well as their spatial relationships. Fractal analysis of the gyral patterns is another method, which we have applied to a small group of patients in an attempt to define subtle simplification of gyral patterns.