MR angiography versus intra-arterial digital subtraction angiography of the lower extremities: activity-based cost analysis.

PURPOSE: The aim of this study was to analyse the costs pertaining to the radiology department of magnetic resonance angiography (MRA) and intra-arterial digital subtraction angiography (DSA) in the evaluation of arterial disease of the lower limbs. MATERIALS AND METHODS: The differential cost of the two procedures, i.e. the sum of equipment costs (amortisation and service contract), variable costs (supplies and related services) and personnel costs (radiologist, radiographer and nurse) was determined. The common cost (auxiliary personnel and indirect internal costs) was also calculated. Finally, the full cost of the two procedures was obtained (sum of differential and common costs). RESULTS: The differential cost of MRA was 186.14 euro (equipment costs: 50.80 euro, variable costs: 75.04 euro, personnel costs: 60.30 euro) while the differential cost of intra-arterial DSA was 238.18 euro (equipment costs: 57.60 euro, variable costs: 90.13 euro, staff costs: 90.45 euro). The estimated common cost was 5.62 euro. Therefore, the full cost of MRA was 191.76 euro and the full cost of intra-arterial DSA was 243.80 euro (27.1% higher). DISCUSSION AND CONCLUSIONS: Intra-arterial DSA costs more than MRA, mainly because of the higher costs of supplies used during the procedure and higher personnel costs (as a result of the longer duration of intra-arterial DSA). It should be noted that our evaluation considers costs pertaining to the radiology department only. It is evident that an economic analysis considering hospital costs as well would result in much higher costs for DSA if post-procedure hospitalisation is required. Our results cannot be simply exported to other radiology departments since they refer to the technology and organisation adopted in our department. However, our cost analysis model can be easily applied to other environments. MRA provides good diagnostic accuracy in the evaluation of arteries of the lower extremities, and its biological cost is far lower than that of intra-arterial DSA (MRA is noninvasive, it does not use ionising radiation, and the contrast medium is safe). Its lower cost is another argument in favour of the use of MRA instead of intra-arterial DSA in the evaluation of lower-extremity arterial disease.

[A PACS system in clinical reality: the Trieste project]. / Un sistema PACS nella realtà clinica: il progetto di Trieste.

The authors report on their experience gained during 5 years' use of a PACS Comm View (AT & T and Philips) in daily clinical practice. The system proved to be very effective in the preparation phase (retrieval of previous investigations), with major advantages over the conventional retrieval modality. The rate of unretrieved images is < 2% and their retrieval times are 10-210 seconds according to different archiving systems. The retrieval of previous images at the two workstations of our department took actually place 20 times a day--that is, much more than in past years. The reporting function was not implemented at the workstation due to its inherent limitations. Communicating the diagnoses (images and reports) to the hospital wards with PACS and RIS was highly appreciated by the referring physicians and a questionnaire distributed among them demonstrated that rapid data access: 1) avoids exam repetitions or unnecessary investigations (81.3% of answers); 2) avoids the request of previous medical records (80% of answers); 3) markedly shortens (two or more days) hospitalization time (100% of answers); 4) has a major impact on treatment choices (100% of answers) and 5) improves the efficiency of referring physicians (93.8% of answers). All the images acquired by the 5 connected modalities were entered in a juke-box with optical disks. Therefore, archive size is likely to reduce in the future. Slightly fewer films (about 14,000 USD/year) are now used.

[Modular project of the Picture Archiving and Communication System (PACS). Preliminary clinical experience. II]. / Sistema PACS a progetto modulare. Esperienza clinica preliminare. II Parte.

In the previous paper in this volume the PAC System installed in the Radiology Department of the University of Trieste has been described and its advantages and limitations have been analyzed, mainly from an operational point of view. This paper deals with the clinical evaluation of the system in ordinary operative conditions. A series of cases with specific characteristics was monitored in order to reveal different performances in both diagnostic process and conclusions using the PACS viewing console (DW) vs. conventional CRT film images on alternators. In a first test, 100 routine (not pre-selected) brain CT cases were independently analyzed by 4 radiologists, each of them giving 2 interpretations of the same case, one based on film and the other on PACS. The data were analyzed by conventional statistical methods, showing a substantial agreement of the results obtained with the 2 modalities. A second test concerned the evaluation of 100 lumbar intervertebral disks by CT, with the same procedure as above. Four radiologists were again asked to decide on film and PACS images about normality, protusion, or herniation of the disks. The results demonstrate the possibility of adequately reporting on the PACS monitor and stress the need of an adequate training period and the efficacy of the image processing capabilities of the system.

[Modular project of the Picture Archiving and Communication System (PACS). Preliminary operational experience. I]. / Sistema PACS a progetto modulare. Esperienza operativa preliminare. I Parte.

Since september 1988 a PAC System (Comm View by AT & T and Philips) has been operating in the Radiology Department of the University Hospital, Trieste. A research project is presently in progress aiming at providing factual evidence for the evaluation of this kind of systems as far as operational, technical, clinical and economic aspects are concerned. The general approach to this research consists in implementing and monitoring a PACS in a stepwise way, starting with a small system connected to some digital modalities only, in order to test the feasibility and effectiveness of the system within a Radiology Department, and to test the possibility of matching the PACS to the Radiological System. The present paper describes in detail the present configuration of this entry-level system and its technical features. The planned development (october 1989) is also depicted. Further developments devise at managing in an integrated way all the radiological images of the four hospitals of Trieste. At present, the PACS is currently used to manage and store on optical disks all the images acquired from the connected modalities plus the related reports, and to perform the reporting sessions for CT examinations (brain and abdomen). The present research effort is devoted to two main areas: clinical evaluation and operational analysis. The object of the operational analysis was the assessment of the impact of PACS on the operations of a Radiology Department. The general approach followed for this research consists in analysing the procedures as they are performed in the conventional way (manual operations), and comparing them to the way they are, or could be, performed using a PACS System (automatic operations). This stage of the project is divided into three phases, concerning respectively the analysis of the organization and operations before PACS, the analysis of the impact of PACS in its initial configuration and the forecast of the influence of PACS in its future setting. A first evaluation concerned the activities carried out from the moment the images are generated to the moment they are ready to be achieved. They include image acquisition, reporting, delivering and returning of images from the departments. The time required to carry out each of the activities involved was recorded, both in the manual and in the automatic version; furthermore, a more detailed analysis was performed on the reporting procedure. The conclusions reached through this analysis are that this kind of operation is mostly affected by the way the Radiology Department is managed, rather than by the tools employed.(ABSTRACT TRUNCATED AT 400 WORDS)