Today I investigated how subdivision occurs near the pulmonary artery and pulmonary vein intersections. Intersections are caused by partial volume effects. I managed to analyse two datasets. In both datasets I have determined that the subdivision process is fairly random (although I still believe that to some extent it depends on the shape, but then again the shape is quite random near PV+PA intersections). The above image is a slice through the MRI showing the different subdivsions (color coded, i.e. a different color for each subdivision). The marked region within the image shows a pulmonary vein what is part of the left atrium but becomes part of the pulmonary artery due to the way that region was subdivided.
Ideally I would have liked the region marked to be a separate subdivision so that it could be merged in with the subdivisions at the atrium. This creates a massive problem where these subdivsions no longer make sense. Previously I have been under the impression that the left atrium would be uniformly subdivided. Thoughts on which directions to proceed: 1. Use a different neighborhood for picking local maximums (currently we use a 26-neighborhood).
Ideally I would have liked the region marked to be a separate subdivision so that it could be merged in with the subdivisions at the atrium. This creates a massive problem where these subdivsions no longer make sense. Previously I have been under the impression that the left atrium would be uniformly subdivided. Thoughts on which directions to proceed: 1. Use a different neighborhood for picking local maximums (currently we use a 26-neighborhood).
No comments:
Post a Comment