Real world federated learning with a knowledge distilled transformer for cardiac CT imaging
Federated learning is a renowned technique for utilizing decentralized data while preserving privacy. However, real-world applications often face challenges like partially labeled datasets, where only a few locations have certain expert annotations, leaving large portions of unlabeled data unused. Leveraging these could enhance transformer architectures' ability in regimes with small and diversely annotated sets. We conduct the largest federated cardiac CT analysis to date (n = 8, 104) in a real-world setting across eight hospitals. Our two-step semi-supervised strategy distills knowledge from task-specific CNNs into a transformer. First, CNNs predict on unlabeled data per label type and then the transformer learns from these predictions with label-specific heads. This improves predictive accuracy and enables simultaneous learning of all partial labels across the federation, and outperforms UNet-based models in generalizability on downstream tasks. Code and model weights are made openly available for leveraging future cardiac CT analysis.
Authors
- Malte Tölle (ORCID: https://orcid.org/0000-0002-0804-5794)
- Norbert Frey (ORCID: https://orcid.org/0000-0001-7611-378X)
- Clemens Scherer (ORCID: https://orcid.org/0000-0003-2816-6793)
- Stefan Simm (ORCID: https://orcid.org/0000-0001-9371-2709)
- Anja Hennemuth (ORCID: https://orcid.org/0000-0002-0737-7375)
- Andreas Leha (ORCID: https://orcid.org/0000-0002-8072-1988)
- Alexander Meyer
- Gerhard‐Paul Diller (ORCID: https://orcid.org/0000-0003-3050-5248)
- Peter Bannas (ORCID: https://orcid.org/0000-0002-7102-534X)
- Tim Seidler (ORCID: https://orcid.org/0000-0002-6158-5087)
- Stefan Groß (ORCID: https://orcid.org/0000-0003-4121-7161)
- Stefan Orwat (ORCID: https://orcid.org/0000-0002-2836-6333)
- Lars Kaderali (ORCID: https://orcid.org/0000-0002-2359-2294)
- Nina Krüger (ORCID: https://orcid.org/0000-0002-2688-9480)
- Tim Friede (ORCID: https://orcid.org/0000-0001-5347-7441)
- Halvar Kelm (ORCID: https://orcid.org/0000-0002-5125-4516)
- Moritz Seiffert (ORCID: https://orcid.org/0000-0002-3940-9079)
- Eike Nagel (ORCID: https://orcid.org/0000-0002-6044-950X)
- Jan Moritz Seliger (ORCID: https://orcid.org/0000-0003-1337-2850)
- Sandy Engelhardt (ORCID: https://orcid.org/0000-0001-8816-7654)
- Simon S. Martin (ORCID: https://orcid.org/0000-0003-3347-4520)
- Florian André
- Sebastian Eble
- Moritz Bednorz (ORCID: https://orcid.org/0000-0002-4981-5732)
- Philipp Garthe
Institutions
- Goethe University Frankfurt (DE)
- Universität Hamburg (DE)
- Zimmer Biomet (Netherlands) (NL)
- Heidelberg University (DE)
- Universitätsmedizin Greifswald (DE)
- University Hospital Heidelberg (DE)
- LMU Klinikum (DE)
- Humboldt-Universität zu Berlin (DE)
- University Hospital Münster (DE)
- Deutsches Herzzentrum der Charité (DE)
- University Medical Center Hamburg-Eppendorf (DE)
- German Center for Infection Research (DE)
- Universitätsmedizin Göttingen (DE)
- German Centre for Cardiovascular Research (DE)
- Kerckhoff Klinik (DE)
- Fraunhofer Institute for Digital Medicine (DE)
- Freie Universität Berlin (DE)
- Charité - Universitätsmedizin Berlin (DE)
- Ludwig-Maximilians-Universität München (DE)
Publication Details
- Journal
- npj Digital Medicine
- Published
- 2025-02-06
- DOI
- https://doi.org/10.1038/s41746-025-01434-3
- Citations
- 13
- Primary Topic
- Privacy-Preserving Technologies in Data
- Type
- article
- Field-Weighted Citation Impact
- 32.25
Funders
- Deutsches Krebsforschungszentrum
- Deutsches Zentrum für Herz-Kreislaufforschung
- Klaus Tschira Stiftung