A grid overlay framework for analysis of medical images and its application to the measurement of stroke lesions

作者：Armitage Paul A^*; Rivers C S; Karaszewski B; Thomas R G R; Lymer G K; Morris Z; Wardlaw J M

来源：European Radiology, 2012, 22(3): 625-632.

DOI：10.1007/s00330-011-2284-2

• Region-of-interest
• Grid overlay
• Volume measurement
• Tissue segmentation
• MRI

Objectives To create and evaluate an interactive software tool for measuring imaging data in situations where hand-drawn region-of-interest measurements are unfeasible, for example, when the structure of interest is patchy with ill-defined boundaries. %26lt;br%26gt;Methods An interactive grid overlay software tool was implemented that enabled coding of voxels dependent on their imaging appearance with a series of user-defined classes. The Grid Analysis Tool (GAT) was designed to automatically extract quantitative imaging data, grouping the results by tissue class. Inter- and intra-observer reproducibility was evaluated by six observers of various backgrounds in a study of acute stroke patients. %26lt;br%26gt;Results The software tool enabled a more detailed classification of the stroke lesion than would be possible with a region-of-interest approach. However, inter-observer coefficients of variation (CVs) were relatively high, reaching 70% in %26quot;possibly abnormal%26quot; tissue and around 15-20% in normal appearing tissues, while intra-observer CVs were no more than 13% in %26quot;possibly abnormal%26quot; tissue and generally less than 1% in normal-appearing tissues. %26lt;br%26gt;Conclusions The grid-overlay method overcomes some of the limitations of conventional Region Of Interest (ROI) approaches, providing a viable alternative for segmenting patchy lesions with ill-defined boundaries, but care is required to ensure acceptable reproducibility if the method is applied by multiple observers.

• 出版日期2012-3