Benchmarking the diagnostic performance of open source LLMs in 1933 Eurorad case reports
Su Hwan Kim1, Severin Schramm2, Lisa C Adams3
1Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, School of Medicine and Health, Technical University of Munich, Munich, Germany. suhwan.kim@tum.de.
NPJ Digital Medicine
|February 11, 2025
Summary
Open-source large language models (LLMs) show promise for supporting radiological diagnostics, with Llama-3-70B closely matching proprietary models like GPT-4o in performance. These AI tools can aid in differential diagnosis for complex cases.
Area of Science:
- Artificial Intelligence in Medicine
- Radiology and Medical Imaging
Background:
- Large language models (LLMs) offer novel applications in medical diagnostics.
- Open-source LLMs present potential advantages in cost and access compared to proprietary models.
- Evaluating LLM performance in real-world clinical scenarios is crucial.
Purpose of the Study:
- To assess the diagnostic performance of open-source and closed-source LLMs in radiological differential diagnosis.
- To compare the accuracy of various LLMs using a large, public dataset and a private dataset.
- To determine the potential of open-source LLMs as clinical decision support tools in radiology.
Main Methods:
- Evaluated 15 open-source LLMs and GPT-4o on 1,933 cases from the Eurorad library.
- LLMs generated differential diagnoses based on clinical history and imaging findings.
- Tested generalizability on 60 non-public brain MRI cases from a tertiary hospital.
Main Results:
- GPT-4o exhibited superior diagnostic performance across both datasets.
- Llama-3-70B demonstrated strong performance, closely following GPT-4o.
- Open-source LLMs are rapidly improving and narrowing the performance gap with proprietary models.
Conclusions:
- Open-source LLMs are becoming increasingly capable for radiological differential diagnosis.
- These models show significant potential as decision support tools in challenging radiological cases.
- Continued development of open-source LLMs could enhance diagnostic workflows in radiology.


