An easy-to-use phantom and protocol for weekly PET quality assessment: a multicenter study.

The authors have developed a simple phantom and dedicated software for the quality assessment of positron emission tomography (PET) scanners. The phantom is a parallelepiped box filled with a relatively low activity 18FDG solution and in which simple test objects are placed. Various image quality parameters are checked, including signal-to-noise ratio, image uniformity, slice thickness, slice sensitivity profile, spatial resolution, and dose calibration accuracy. Automatic image analysis consists in detecting surfaces and objects, defining regions of interest, acquiring reference point coordinates, and establishing gray-scale profiles. The total time needed for quality assessment (preparation and image acquisition) is less than 15 min with 37 MBq (1 mCi) 18FDG. The system's ease of use encourages frequent image quality assessment-for example, the comparison of PET scanners in interdepartment studies and the monitoring and evaluation of possible drifts over time. By way of an example, the authors present weekly quality assessment results obtained over up to 7 months at four PET facilities.

[The need for invasive diagnostic investigations (coronaro-ventriculography), interventions using extracorporeal circulation and coronary angioplasty in a defined population of Emilia-Romagna]. / Fabbisogno di indagini diagnostiche cruente (coronaro-ventricolografie), di interventi in CEC e di angioplastiche coronariche in un campione definito di popolazione dell'Emilia-Romagna.

Working on a limited and controlled population of 100,000 living in the territory of Imola, in northern Italy, we tried to determine the need for coronary arteriography examinations, CABG interventions and PTCA procedures (similarly to the 1980 Minnesota survey). Indications for diagnosis or treatment were made according to agreement criteria of published data in 1990. In the 3 year time (1989-91) of this survey, indication to coronary arteriography was done in 433 pts. (367 atherosclerotic, 58 valvular and 8 with other etiologies). 57.7% (250/433) of the pts. were treated with CABG or PTCA, and 42.3% (202/433) were treated medically. Of the 367 pts. documented as having coronary ischemia, 54.5% had further invasive therapy: 35.4% CABG and 19% PTCA. For a population of 100,000 annual need has been estimated as follows: 145 catheterization procedures (99% coronary arteriography), 60 extracorporeal circulation procedures, and 24 PTCA interventions. Comparing programming estimates done by the national Health System for the needs of a population group in Northern Italy, it is clear that they are underestimating the real needs by 50%, and such an important underestimation implies important and pressing considerations for the future planning of the health care of this important pathology.