Beginning in 1985 with the first congress on Computer Assisted Radiology (CAR), PACS, modelling and the other five themes, including computer aided diagnosis and computer assisted surgery as part of application programming, provided the guiding focus for some insightful publications between 1985 and 1989 relating to the future of medicine generally [5], radiology [6, 8, 9, 11] and surgery [7, 10, 13].

Celebrating the 20th Anniversary of Los Angeles—Berlin partnership, a significant milestone event, relating to picture communication and teleradiology, was achieved for the first time in 1987. This consisted of the transatlantic transmission of CTs between the CAR venue in Berlin and Multi Planar Diagnostic Imaging in Los Angeles, organised by Michael Rhodes (MPDI) and the TUB Computer Graphics Research Group.

During this period, the TUB CG Group proceeded with their research on medical geometric modelling, experimenting with 3D voxel models (Dietmar Jackél), 3D B-spline models (Bernd Knobloch), 3D triangular surface models (Klaus Tönnies), see Fig. 1, and 3D natural objects (Harald Scharnweber) [12].

3D Modelling of the Heart, Klaus Tönnies, TUB 1987 [12]

The Honorary Chairman of CAR 1989, Heinz Oeser, professor of radiology at the Free University of Berlin and former President of the German Radiological Society, based on his paper at CAR ‘85 entitled “CAR—Flaggschiff der Medicine” [5], in which he observes:

”CAR will decisively effect the development of medicine, impacting the structure of the health care system—giving direction as the flagship of medicine” continued in 1989 “… to take and keep course towards deepening the knowledge within our radiological community and a good cooperation between radiology, data processing and informatics. It cannot and must not be avoided to incorporate CAR into the structure of radiology”.

A further significant milestone event in 1989 was that the then director of radiology at the Charité in Berlin (then the city still being the capital of the DDR (Deutsche Demokratische Republik), Michael Lüning, introduced the “Gesellschaft für Medizinische Radiologie der DDR” as a cooperation partner of CAR 1989, thereby recognising the official existence of West Berlin by the DDR government. One interesting gesture of the beginning of the peaceful “Wende” (the historical period around German reunification) starting later that year.

As a consequence of that “Wende” and related to other changes in Berlin, Bibiana Moser-Illmann, who was the organising person of CAR until then, gave up a secure job at the West Berlin governmental organisation and worked for CAR as a professional congress organiser. She was joined by Franziska Schweikert and with their never-ending energy, they built up the new political and organisational infrastructure of CAR(S), needed for these fast-moving times. Bibiana retired in 1995, after giving her full and highly valued professional attention to CAR for over 10 years. During the last 30 years, Franziska Schweikert with her enthusiasm and understanding of what CARS is all about and unimpeded by any forces of divergence, has nurtured CARS and its international and interdisciplinary community in the spirit as was conceptualised over 40 years ago, in 1983.

By 1989, when for the last time CAR took place in the divided city of Berlin, over twenty medical and technical societies from Europe, USA and Japan became cooperating partners of CAR. SCAR (later renamed SIIM) and EuroPACS (later renamed EuSoMII), however, played a special role in the way that CAR 1989 was recognised by them as the event to which they adjusted their own conferencing and publishing activities. The author of this editorial, being a founding member of SCAR and EuroPACS, thoroughly enjoyed being part of these international organisations and their visions. It was a lesson for the learning to listen to the international and interdisciplinary opinions at first hand and trying to deduce and accommodate important reflections into the CARS Congress.

One of the decisive conclusions in this regard was reached with RISC/SCAR in 1988, specifically to explore the amalgamation of strength between CAR and RISC/SCAR, with the aim to introduce CAR to the US and SCAR to Europe. This was largely supported by two influential radiologists from the US, Richard Friedenberg and Ron Arenson. Indeed, in the year 1990, SCAR and CAR had their first joint meeting in Anaheim, California, followed by further joint meetings in the USA in 1992 and 1994. During these events, Allan Farman, University of Louisville School of Dentistry, decided to join CAR with the Computed Maxillofacial Imaging Congress.

EuroPACS decided to join CAR(S) whenever CAR(S) took place in Europe, an arrangement for over 20 years, until PACS became a “normal” tool in health care. Then the succeeding society EuSoMII acquired a new focus, while becoming part of the ECR.

As indicated above, during the first 10 years of CAR, there was a steady increase of support from international societies. In 1995 and with Alexander R. Margulis as the Honorary President of CAR, some thirty societies and institutions, incl. SPIE, BIR, RCR, DRG, ISCAS and the “Society for Computer Assisted Radiology, P.R. China” joined CAR. Of about 200 presentations in 1995, it may be appropriate to single out just one on Artificial Intelligence, that showed already 30 years ago what is the coming age in health care [14]. Another pointer to the future that evolved in many years from think tanks accompanying CAR, resulted in a presentation in 1995 on the “Hospital of the Future” [15]. Increasingly, also digital models started to be given more explicit attention, even though often limited to (or confused with) 3D images or 3D solid model construction [16]. A long way still to go to Multi Entity Bayesian Network models or AI foundation models.

Also by 1995, CAR had established itself as an international meeting and was ready to move to other countries and other sites in Germany outside Berlin in which active research activities in CAR and Computer Assisted Surgery (CAS) justified to choose other venues. Attractive cities were selected, such as Paris 1996, 1999 and 2002, Tokyo 1998 and 2022, San Francisco/Stanford 2000, London/Cambridge 2003, Osaka 2006, Barcelona 2008, 2015, 2017 and 2024, Geneva 2010, Pisa 2012, Heidelberg 2013 and 2016, Fukuoka 2014, Rennes 2019, and Munich 2020, 2021 and 2023. A few selected CARS congress events in venues that took place outside Berlin (except for the CARS 2005 20th and 2025 40th Anniversary) with some of their highlights are summarised in the next section.