Mosaic Clinical Technologies, the technology services division of Radiology Partners, has filed a citizen petition with the U.S. Food and Drug Administration (FDA).
The petition requests clarification on when commercially distributed AI vision language models (VLMs) used for diagnostic medical image analysis should be regulated as medical devices.
The petition argues that VLMs specifically designed, trained, and marketed for diagnostic imaging analysis meet the statutory definition of a medical device under the Federal Food, Drug, and Cosmetic Act, regardless of whether downstream users perform additional fine-tuning before clinical deployment. Mosaic contends that the practice of medicine exemption does not shield developers from FDA oversight when they commercially distribute models capable of performing diagnostic image analysis.
The petition raises patient safety concerns about VLMs deployed without FDA premarket review, including risks of bias from unrepresentative training data, lack of transparency, and absence of standardized validation and performance monitoring requirements.
Mosaic is asking the FDA to clarify when a VLM constitutes a finished medical device rather than a component, and to define the respective responsibilities of developers, distributors, and healthcare organizations in the deployment of diagnostic imaging VLMs.
