Normal perfusion or fixed defects predict a benign prognosis in patients after successful PTCA. The presence of stress-induced reversible defects appears to be the best predictor of future cardiac events.

The results confirm that the net hepatic arterial blood flow is increased in patients with cirrhosis. Radionuclide angiography accompanied by calculation of arterial perfusion indices may provide semiquantitative parameters of net hepatic arterial blood flow.

M. Wiedermann und O. Charamza 7 Abbildungen os de,-Radioisolopenobledung (Voistand: ¡)r. ,m'd. M. Tliedermonn) des f/n i,'e,sitälskrankenhw, ses Oloinouc/OSSU iiiul dem Zeniralinslitul fur Kernforschung, flosseiidorf (I)irektor: Piof. Dr.-Ing. If. Faulstich) Heruntergeladen von: NYU. Urheberrechtlich geschützt.

These findings suggest a benign prognosis in patients with normal SPECT (regardless of the L:H ratio). Conversely, all patients with ischemia are at high risk for future cardiac events. Quantification of the Tl-201 lung uptake seems to be valuable in evaluations of disease prognosis, especially in patients with fixed defects.

No abstract

Assuming that colloidal particles of ls*Au or goy are adsorbed by the synovial surface so that they form a very thin plane source of activity, the dependence of the absorbed dose on the distance from the source is calculated according to Berger's method and the methods of Loevinger et al. and Cross. Considering an infinitely thin plane source, a model often used in the literature, excellent agreement among the three methods is obtained at distances above 0.05 mm, A plane source having a thickness of 20-30 pm appears to be a more reasonable model, approximating more closely to the actual distribution of colloidal particles in the synovial membrane. These two approaches are compared and shown t o give the same dose at distances greater than 0.1 mm. IntroductionRadioactive colloids, mainly 198Au and 9OY, are often used for the treatment of some joint conditions (

A method for the determination of regional blood flow is described, using a 133Xe inhalation technique and a three-compartment analysis. The constants characterizing the individual blood compartments are determined by setting precisely the constants in the empirical formulae. In the desaturation area the fitting of curves by the least-squares method is applied, checking at the same time that the given initial conditions are satisfied. The time shift of the measured curves may also be considered. The consistent application of the fitting technique leads to a decrease in the computer time needed t o about one-half of that required by other digital methods.

Radionuclide myocardial perfusion imaging (MPI) has been on the rise in Europe and the USA. Details on nuclear cardiology in the Czech Republic are not available as yet, as it is impossible to obtain comprehensive data from official registers owing to different methods of reporting and data evaluation. A questionnaire concerning nuclear cardiology activity and practice in 2001 was sent to all nuclear medicine departments in the Czech Republic. All 48 departments completed the questionnaire. In 2001, 50 planar and 54 tomographic (SPET) scintillation cameras were used. The average age of the SPET cameras was 5 years (13% of SPET cameras were >8 years old). Out of the 48 centres, 39 (81%) provided a nuclear cardiology service; the total number of cardiological studies was 15,740 in 2001 (1.5 studies/1,000 population/year). The most frequently employed method was MPI (81.7%), the frequency of which had increased by 10% compared with 2000; 26 of the 39 (67%) departments reported that MPI activity was increasing. Nevertheless, the Czech Republic nuclear cardiology activity remained below the European average (2.2/1,000 population in 1994) and, particularly, below activity in the USA (15/1,000 in 1997). The activity was rather unevenly spread. Whereas two centres with >1,000 studies/year accounted for 20% of the total MPI studies, 16 of 39 (41%) departments exhibited low activity (<200 studies/year) and accounted for only 15% of the total MPI studies. The use of SPET increased from 91% in 2000 to 94% in 2001 (only three institutes performed planar examinations). The most widely used tracer was (99m)Tc-MIBI (60% of total MPI), followed by (201)Tl (21%) and (99m)Tc-tetrofosmin (19%). ECG-gated SPET was employed by 20/39 (51%) centres, of which 11 (28%) performed it as a standard examination; 39% of the total MPI studies included this technique. Thirteen percent (5/39) of the departments used attenuation correction, and 69% (27/39) of the departments used a prone projection. Equilibrium radionuclide ventriculography, with 2,317 examinations (14.7%), ranked second among all nuclear cardiology methods, followed by first-pass angiocardiography (406 studies, 2.6%) and (18)F-FDG (163 studies, 1%).