Objective:To explore the application of three-level storage pattern(on-line,near-line,off-line)to picture archiving and communication system(PACS),and to find a solution to the long-term storage of medical imaging data in PACS of the basic unites.Methods:To realize the on-line storage of medical imaging data by the redundant array of independent disk(RAID)of host-server;To realize the near-line storage of medical imaging data by the network attached storage(NAS);To realize the off-line storage of medical imaging data by the tape-drive.Results:The long-term storage of medical imaging data in PACS has been available in our hospital for one year since the three-level storage pattern used in PACS.It not only realizes the on-line access of enormous amount of medical imaging data,but also protects the imaging data's integrity when the on-line data damaged by human's activities or fire,etc.Conclusion:The application of three-level storage pattern in PACS,which is characterized as low expense,dependable performance,simple maintenance,can become perfect pattern in the basic Level hospital.

Objective To investigate the use of the minimizing picture archiving and communication system (mini PACS) in practical work and to realize the advent of filmless radiology Methods A PC based ethernet was set up The medical imaging equipments including CT, MR, digital fluoroscopy, DSA, and a laser camera were combined with the ethernet, and the digital imaging network (DIN) was integrated with the medical diagnostic imaging system (MDIS) In this way, the radiology information system (RIS) was established Through one of the PC workstations with a double network card, this RIS was connected to the hospital information system (HIS) Results The mini PACS has been repeatedly used for more than 2 years The system in Radiology department has been established and improved With the present digital imaging system, such functions as the acquiring, storing, transmitting, printing, and browsing of digital images have been put into practice, all in accordance with the manners of the digital imaging communication in medicine 3 0 (DICOM 3 0) Digital imaging and diagnostic reports were managed through Microsoft Access database Images may be kept on line in different kinds of equipment for 3-6 months All images have been recorded on CD R disks, so as to be kept off line permanently So far, over 32 700 reports have been stored in the database From mini PACS HIS terminals images and diagnostic information may be acquired on a limited scale Conclusion mini PACS needs only a low cost of investment and operation Its maintenance is simple and its performance is efficient The main functions of the PACS can mostly be achieved There lies a bright prospect for its use in small and medium hospitals