Improving the imaging of calcifications in CT by histogram-based selective deblurring

摘要: ABSTRACT Imaging of small high-density structures, such as calcifications, with computed tomography (CT) is limited by the spatial resolution system. Blur causes calcifications to be imaged lower contrast and overestimated volume, thereby hampering analysis vessels. The aim this work reduce blur applying three-dimensional (3D) deconvolution. Unfortuna tely, high-frequency amplification deconvolution produces edge-related ring artifacts enhances noise original artifacts, which degrades imaging low-density structures. A method, referred Histogram-based Selective Deblurring (HiSD), was implemented avoid these negative effects. HiSD uses histogram information generate a restored image in low-intensity voxel observed combined high -intensity th e deconvolved image. To evaluate we scanned four in-vitro atherosclerotic plaques carotid arteries multislice spiral CT microfocus (P CT), used reference. Restored images were generated from images, qua litatively quantitatively compared their corresponding P images. Transverse views maximum-intensity projections show decrease 3D. Measurements areas 27 total volumes calcification 4 that overestimation smaller for (mean-error: 90% area; 92% vol ume) than (14 3%; 213%, respectively). qualitative quantitative analyses can impr oved considerably .Key words: tomography, calcification, decon volution, deblurring, PSF, resolution, CT, quantification.