Precision of syndesmophyte volume measurement for ankylosing spondylitis: a phantom study using high resolution CT.

Abstract

Ankylosing Spondylitis is a disease characterized by abnormal bone structures (syndesmophytes) growing at intervertebral disk spaces (IDS). The growth of syndesmophytes is typically monitored by visual inspection of radiographs. The limitations inherent to the modality (2D projection of a 3D object) and rater (qualitative human judgment) entail a possibly important loss in sensitivity. We previously presented a method designed to overcome both limitations: a computer algorithm that quantitatively measures syndesmophytes in the 3D space of a high-resolution computed tomography scan. To establish the method's usefulness for longitudinal studies, it is necessary to assess its precision (repeatability) which can be affected by the limitations of both the algorithm itself and the imaging modality. To this end, an anthropomorphic vertebral phantom with syndesmophytes in 4 IDSs was manufactured. It was scanned 22 times with varying positions and resolutions. The syndesmophyte volumes extracted by our algorithm have an average coefficient of variation of 1.6% per IDS and 0.85% for the total.

DOI: 10.1109/IEMBS.2009.5335439

Cite this paper

@article{Tan2009PrecisionOS, title={Precision of syndesmophyte volume measurement for ankylosing spondylitis: a phantom study using high resolution CT.}, author={Sovira Tan and Jianhua Yao and Lawrence Yao and Michael M. Ward}, journal={Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference}, year={2009}, volume={2009}, pages={3577-80} }