Automatic Extraction of Structured Information from Brain MRI Reports Using an Open-Weight Large Language Model
This study addresses the challenge of automatically extracting structured clinical information from Dutch-language neuroradiology reports, a key bottleneck for large-scale brain MRI research. It presents the first systematic evaluation of the open-source large language model LLaMA 3.1 for this task, introducing a structure-similarity-based strategy for few-shot example selection. By combining multilingual inputs—original Dutch reports and their English translations—with tailored prompt engineering, the approach extracts 30 key variables from 947 reports. The model achieves high accuracy on visual rating scales (e.g., 94% for Fazekas score) and detection of microbleed mentions (93%). Few-shot prompting substantially improves extraction of numeric variables such as microbleed counts (92% accuracy), though localization-related variables remain challenging.