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Biomedical subjects

Michael Landmann

Publications and source records attributed to Michael Landmann.

2 recordsLinked to original sources

Internal radionuclide therapy: the ULMDOS software for treatment planning.

Before therapy with unsealed radionuclides, a dosimetry assessment must be performed for each patient. We present the interactive software tool ULMDOS, which facilitates dosimetric calculations, enhances traceability, and adequate documentation. ULMDOS is developed in IDL 6.1 (Interactive Data Language) under Windows XP/2000. First the patient data, the radiotracer data, and optionally urine and serum data are entered. After loading planar gamma camera images and drawing regions of interest, the residence times can be calculated using fits of the time activity data to exponential functions. Data can be saved in ASCII format for retrospective examination and further processing. ULMDOS allows one to process the dosimetric calculations within a standardized environment, spares the time-consuming transfer of data between different software tools, enables the documentation of ROI and raw data, and reduces intraindividual variability. ULMDOS satisfies the required conditions for traceability and documentation as a prerequisite to routine use in clinical settings.

Algorithms↗

Quantitative image reconstruction in PET from emission data only using cluster analysis.

Quantitative image reconstruction in positron emission tomography requires attenuation correction. In case the attenuation correction is not measured separately, under certain conditions this can be determined from the emission data alone. We present a method based on cluster analysis that assumes only 3 empirical attenuation coefficients, i.e., 0.095 cm-1 for soft tissue, 0.02 cm-1 for lung, and 0 cm-1 for air. The subsequent image reconstruction takes place in an iterative fashion, through maximization of image likelihood. For the mathematical thorax phantom used in the present study, the results are comparable to those obtained after separate measurement of the attenuation correction.

Cluster Analysis↗