Ludwig Strauss attended high school in Heppenheim and graduated in 1968. He studied medicine from 1969 to 1975 at the Justus Liebig University in Gießen and mathematics from 1973 to 1975 at the same university. He graduated Medical School in 1975 and got the approbation (medical license) in 1976. He did his thesis with the title "Comparative studies of different radio-in-vitro-tests for the evaluation of the thyroid function under consideration of different parameters" in November 1978. He was board certified for Nuclear Medicine in October 1982 and also for Radiology in January 1986. He then became an assistant professor of radiology with a thesis entitled "Quantitative and qualitative liver- and spleen scintigraphy based on single-photon-emission-tomography (SPECT) in comparison to the transmission computed tomography (CT)". In October 1992 he became a full professor of radiology at the University of Heidelberg. Ludwig Strauss was resident in internal medicine from 1975 to 1978. He then moved to the German Cancer Research Center and worked as a resident of nuclear medicine (1978-1982). From 1982-1986 he was resident in radiology at the Institute of Radiology of the University Medicine Mannheim. In 1987 he moved again to the German Cancer Research Center, Department of Oncological Diagnostics and Therapy (Chief: Prof. Dr. G. van Kaick) and was responsible for one of the first whole-body positron emission tomography (PET) system in Germany.
Strauss' research focused on the implementation of new molecular imaging tomographic techniques for the improvement of oncological diagnostics and the individualization of tumor therapy. He propagated with his group the use of PET in oncology in the late 80's.