MIC-III--an integrated software package to support experiments using the radioactive microsphere technique.

MIC-III is a versatile program system to support gamma spectrometry data management and data collection for experiments using the radioactive microsphere technique. It is mainly written in PASCAL and running on a minicomputer. Hierarchical organ dissection schemes are used for unique classification and identification of samples. For each series of experiments, up to 12 different nuclides and up to 20 different organ dissection schemes can be handled simultaneously. Sample weights are collected on-line and sample radioactivities are measured automatically by gamma spectrometry under process control. The spectra with a resolution of 1022 channels are analyzed using a modified linear regression technique and a strategy to compensate for global spectrum shifts. The spectrum deconvolution algorithm was evaluated by calculating the recovery indices for known nuclide mixtures and compared to the stripping method, matrix method and a linear regression technique using window counts. Recovery values produced by MIC-III are better balanced than those of the other methods. MIC-III showed the smallest dispersion of the recovery index and exhibited least error accumulation in case of spectrum shift. MIC-III computes regional blood flow and arterio-venous shunt, and provides interfaces to customized programs or statistical software packages for further analysis. It has successfully been employed in more than 140 experiments.