Biomedical subjects
Publications and source records attributed to H Newiger.
Technical and physical requirements and parameters of positron emission tomography are discussed. Scanners and cyclotrons are described and PET is compared with SPECT.
The physical principle of PET is discussed, and its advantages compared with SPECT are presented. Starting from the status of PET today, future developments are discussed with special reference to three-dimensional acquisition and reconstruction.
Explore the source record for details and available documents.
A new flood phantom is presented. It combines patient like emission spectra, homogeneous activity distribution, and mechanical stability. Its properties and easy handling makes it the flood phantom of choice for measuring the homogeneity of a gamma camera or for correcting SPECT studies.
The imaging of positron-emitting isotopes using a gamma camera requires special collimators. A ray-tracing method for simulating the point-spread function of collimators and, therefore, the total gamma camera system is presented. Simulated data obtained by this method showed good agreement with experimental data. Using this method, optimal lead and tungsten collimators for positron emitters were devised; at an object distance of B = 100 mm, these yielded a point-spread function with an FWHMtot = 9.1 mm using an intrinsic resolution of FWHMintr = 8.0 mm.
In this paper a method is demonstrated for recording transverse profiles of the time of flight in samples with a local resolution of a few millimetres and a time resolution of 10 ns. Good agreement between the theoretical and the measured curves is shown for some test objects.