G. Pozzi

Conceptual Modeling of Temporal Clinical Workflows

The diffusion of clinical guidelines to describe the proper way to deal with patients situations is spreading out and opens new issues in the context of modeling and managing (temporal) information about medical activities. Guidelines can be seen as processes describing the sequence of activities to be executed, and thus approaches proposed in the business context can be used to model them. In this paper, we propose a general conceptual workflow model, considering both activities and their temporal properties, and focus on the representation of clinical guidelines by the proposed model.

A Peano-Hilbert derived algorithm for compression of angiocardiographic images

The authors implemented some irreversible compression techniques on single images coming from angiocardiographic films. They used two different types of threshold on the brightness difference between corresponding pixels of the original image and the reconstructed one. The two methods were brightness error limitation (BEL) and pseudo-gradient adaptive BEL (PABEL). The results of irreversible compression were coded by a reversible compression method based on Lempel-Ziv algorithms. To take advantage of local properties of angiographic images a scan path based on Peano-Hilbert plane-filling curve was implemented. Applying the compression techniques to some 80 different images the authors obtained a mean compression of more than 6:1. A cardiologist did not identify significative diagnostic differences between original images and reconstructed ones.<<ETX>>

Temporal clinical data modeling and implementation for PTCA patients in an OODBMS environment

Often clinical information carries along temporal aspects; the management of temporal clinical data must allow queries about temporal relations between clinical events. Object-oriented techniques applied to database management systems allow the definition of suitable data structures: some facilities allow the use of predefined structures when defining new ones. This approach seems to be useful in designing and implementing systems to manage complex clinical data, such as the temporal data. The authors defined and implemented a temporal clinical data model, to manage temporal data specified at different levels of granularity. This paper describes a temporally oriented medical record, based on the temporal clinical data model, managing data from patients subjected to percutaneous transluminal coronary artery angioplasty (PTCA). The authors developed it on a Sun workstation with Unix operating system and ONTOS as object-oriented DBMS. The user-interface runs on Open Windows.<<ETX>>

Effective data compression of angiocardiographic static images with PABCEL method

The authors applied a new compression method, called the pseudogradient adaptive brightness and contrast error limitation (PABCEL) method, on single images coming from angiocardiographic films. The PABCEL algorithm aims at limiting the maximum difference of brightness between corresponding pixels of the original image and the reconstructed images on the Peano-Hilbert scan path. The authors applied the compression method to 168 images coming from 14 different angiocardiographic examinations. With the lowest threshold values a mean compression ratio of about 8:1 was obtained. Cardiologists did not identify significant differences between original images and reconstructed images. A qualitative and quantitative evaluation of the results has been carried out.<<ETX>>

Continuing education of physicians and nurses in the DBMS Area

High evolution rates of instrumentation used in clinical cardiology departments make difficult demands on personnel continuing education, both for physicians and for nurses. New instruments, providing advanced and locally-upgradable performances, call for specific skills to be acquired via appropriate training. More wide-spectrum instrumentation, typically based on personal computers and DBMS oriented, may call for different and deeper educational approaches as much as they allow the local clinical user to design the set of performances he really needs and may effectively use. We describe experiences we had in our department. In both specific training and wide-spectrum deeper education, including DBMS, we took full advantage of the full-time presence of young graduates in biomedical engineering and computer science.

MS*2/cardio-an implementation of a multiservice medical software

A medical record with multiservice performance is described. The package runs on MS-DOS and can be set up to share data via a local area network. The package is made of three units. A time-oriented medical record stores information about the patients and analyzes collected data. A drug-to-drug interaction program warns if prescribed drugs trigger any adverse interaction. A drug doser program helps to find out the posology of drugs. The three units are completely integrated. They can share information and each of them can be easily activated from the others. In some cases activation is automatic. The package is specialized for cardiac patients.<<ETX>>