Keywords:
Image registration, Segmentation, Computer Applications-Detection, diagnosis, CT-Angiography, Catheter arteriography, CAD, Computer applications, Cardiovascular system, Arteries / Aorta
Authors:
X. Gao1, S. Boccalini2, P. Kitslaar1, R. P. J. Budde2, H. Reiber1; 1leiden/NL, 2Rotterdam/NL
Methods and Materials
Population and CT protocol
Contrast enhanced cardiac CT scans of 15 candidates for TAVI were acquired on a 320-row detector scanner (Aquilion ONE,
Toshiba Medical System,
Japan).
Reconstructed slice thickness was 0.5mm at 0.25mm intervals.
Diastolic reconstructions were used.
Automatic measurement of aortic annulus
The fully automatic annulus size measurement algorithm was based on a novel segmentation method combing image registration and deformable subdivision surface model fitting with results shown in Figure 1(3),
and the detection of the location of the annulus as shown in Figure 2 (4),
extraction of the contour and calculation of the area,
area-derived radius,
max and min diameters.
Reference standard
One observer (a radiologist with 5-year cardiovascular imaging experience) defined the location of the aortic annulus purely manually,
and corrected the automatically extracted contours semi-automatically.
The correlation of the area,
area-based radius,
max and min diameters between the automatic algorithm and the observer was computed and compared,
as well as the mean error and standard deviation.