A cardiac contouring atlas enabled reproducible delineation of 15 cardiac segments, with mean DICE similarity of 0.60-0.73 for left ventricular segments and <1 Gy dose variation for most regimens.
Does a cardiac contouring atlas enable reproducible contouring of left ventricular and coronary arterial segments on radiotherapy CT-planning scans?
A cardiac contouring atlas provides a reproducible method for delineating left ventricular and coronary arterial segments on radiotherapy CT scans, which is critical for assessing cardiac radiation doses.
Background and purposeThe heart is a complex anatomical organ and contouring the cardiac substructures is challenging. This study presents a reproducible method for contouring left ventricular and coronary arterial segments on radiotherapy CT-planning scans.Material and methodsSegments were defined from cardiology models and agreed by two cardiologists. Reference atlas contours were delineated and written guidelines prepared. Six radiation oncologists tested the atlas. Spatial variation was assessed using the DICE similarity coefficient (DSC) and the directed Hausdorff average distance (d→H,avg). The effect of spatial variation on doses was assessed using six different breast cancer regimens.ResultsThe atlas enabled contouring of 15 cardiac segments. Inter-observer contour overlap (mean DSC) was 0.60–0.73 for five left ventricular segments and 0.10–0.53 for ten coronary arterial segments. Inter-observer contour separation (mean d→H,avg) was 1.5–2.2 mm for left ventricular segments and 1.3–5.1 mm for coronary artery segments. This spatial variation resulted in <1 Gy dose variation for most regimens and segments, but 1.2–21.8 Gy variation for segments close to a field edge.ConclusionsThis cardiac atlas enables reproducible contouring of segments of the left ventricle and main coronary arteries to facilitate future studies relating cardiac radiation doses to clinical outcomes.
Duane et al. (2017) studied Radiotherapy planning (n=6). Cardiac contouring atlas was evaluated on Spatial variation (DICE similarity coefficient and directed Hausdorff average distance). A cardiac contouring atlas enabled reproducible delineation of 15 cardiac segments, with mean DICE similarity of 0.60-0.73 for left ventricular segments and <1 Gy dose variation for most regimens.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: