| Popis: |
The authors developed a bi-directional 1249/625 lines converter, able to store and to replay high resolution (1249 lines) video images, from Component Record Video (CRV) Optical Laser (Analogue) Videodisks. Image quality was evaluated four ways: (1) The authors evaluated Quantitative Coronary Angiography (QCA) on standard coronary test phantoms using enhanced CRV storage images digitally processed and also compared 78 arterial measurements ranging 0.65 to 4.85 mm both front the digital hard disc (D) and the CRV optical disc (CRV), using the same QCA analytical package. No systematic over or underestimation occurred, the mean variability was inferior to 0.1 mm and results were similar to the results obtained in the literature from digitally stored images. (2) Outside experts compared 593 static images stored on CRV discs to the same images stored in 1024/sup 2/ digital format blinded to source of image. The four experts found no visual or medical difference in 98% of evaluated images and minor differences in the remainder. (3) 90 representatives from 63 institutions compared images from both a digital hard drive and the enhanced CRV optical (analogue) storage. During the test they were blinded as to the source of the images. The representatives found no difference in image resolution, quality diagnostic accuracy, and medical relevance. (4) Two of the experts also compared the enhanced CRV optically stored image to the image obtained on simultaneously recorded 35 mm cine film, and found the enhanced CRV stored image to be superior or similar, but never inferior to the film image. It is concluded that High-Resolution CRV storage represents a cost effective solution for excellent image quality equivalent to digitally stored images, permitting permanent electronic archiving inside the cath-lab, and allowing digital image processing and digital DICOM network and CD-ROM based image communication. |
