ABSTRACT
KHOSPAD is a project aiming at improving the quality of the process of patient care concerning general practitioner-patient-hospital relationships, using current information and networking technologies. The studied application field is a cardiology division, with hemodynamic laboratory and the population of PTCA patients. Data related to PTCA patients are managed by ARCADIA, an object-oriented database management system developed for the considered clinical setting. We defined a remotely accessible view of ARCADIA medical record, suitable for general practitioners (GPs) caring patients after PTCA, during the follow-up period. Using a PC, a modem and Internet, an authorized GP can consult remotely the medical records of his PTCA patients. Main features of the application are related to the management and display of complex data, specifically characterized by multimedia and temporal features, based on an object-oriented temporal data model.
Subject(s)
Databases as Topic , Internet , Medical Records Systems, Computerized , Angioplasty, Balloon, Coronary , Cardiology Service, Hospital , Computer Security , Confidentiality , Data Display , Database Management Systems , Family Practice , Follow-Up Studies , Hemodynamics , Hospital-Patient Relations , Hospital-Physician Relations , Humans , Information Storage and Retrieval , Laboratories, Hospital , Microcomputers , Multimedia , Physician-Patient Relations , Telecommunications , User-Computer InterfaceABSTRACT
We defined, implemented and tested two new methods for irreversible compression of angiocardiographic still images: brightness error limitation (BEL) and pseudo-gradient adaptive brightness and contrast error limitation (PABCEL). The scan path used to compress the digital images is based on the Peano-Hilbert plane-filling curve. The compression methods limit, for each pixel, the brightness errors introduced when approximating the original image (i.e. the difference between the values of corresponding pixels as grey levels). Additional limitations are imposed to the contrast error observed when considering along the scan path consecutive pixels of both the original and the reconstructed image. After previous testing on angiocardiographic images selected as clinically significant from 35 mm films, we enlarged our experiment to a set of 38 coronary angiograms digitally acquired. BEL and PABCEL methods were experimented according to several values of the implied thresholds. Up to a compression ratio of 9:1 for the BEL method and 10:1 for the PABCEL method, no deterioration of the reconstructed images were detected by human observers. After a visual evaluation, we performed a quantitative evaluation. The visualization of pseudo-colour difference images showed the capability of BEL and PABCEL for preserving the most significant clinical details of the original images. For comparison, we applied the JPEG (joint photographic experts group) image-compression standard to the same set of images. In this case, pseudo-colour difference images showed a homogeneous distribution of errors on the image surface. Quantitative compression results obtained by testing the different methods are comparable, but, unlike JPEG, BEL and PABCEL methods allow the user to keep under his direct control the maximum error allowed at each single pixel of the original image. These different behaviors are confirmed by the values obtained for the considered numerical quality quantifiers.
Subject(s)
Angiocardiography , Algorithms , Coronary Disease/diagnostic imaging , Humans , Software DesignABSTRACT
HyperCare is a prototype of a decision support system for essential hypertension care management. The medical knowledge implemented in HyperCare derives from the guidelines for the management of mild hypertension of the World Health Organization/International Society of Hypertension, and from the recommendations of the United States Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure. HyperCare has been implemented using Chimera, an active database language developed at the Politecnico di Milano. HyperCare proves the possibility to use active database systems in developing a medical data-intensive application where inferential elaboration of moderate complexity is required.
Subject(s)
Decision Making, Computer-Assisted , Guideline Adherence , Hypertension/therapy , Practice Guidelines as Topic , Databases as Topic , Humans , Programming LanguagesABSTRACT
We defined and implemented three new irreversible compression techniques for digital angiocardiographic static images: brightness error limitation (BEL), pseudo-gradient adaptive brightness error limitation (PABEL), pseudo-gradient adaptive brightness and contrast error limitation (PABCEL). To scan digital images we implemented an algorithm based on the Peano-Hilbert plane filling curve. We applied our compression techniques to 168 static images selected from angiocardiographic 35-mm films. We achieved best compression results applying the PABCEL method, obtaining a mean compression ratio of about 8:1. Consulted cardiologists did not find significant diagnostic differences between original images and reconstructed ones.