CMUH SWAN Microbleed Set

This collection of clinical susceptibility-weighted brain MRI comes from China Medical University Hospital in Taichung, Taiwan. Researchers at the hospital's Artificial Intelligence and Robotics Innovation Center gathered it retrospectively under institutional review board approval to test whether cerebral microbleed detectors trained on synthetic lesions transfer to real scans. Microbleed-free exams served as hosts for inserting synthetic microbleeds, and exams with real microbleeds were used for real-data training and testing. The images are not public.

Composition

205 MRI examinations: 104 with at least one microbleed and 101 without. The paper splits them into a training set of 78 positive exams (687 lesions) and 75 negative exams, and a hold-out test set of 26 positive (171 lesions) and 26 negative exams. Positive exams were assigned to the two sets by lesion burden (fewer than 5, 5 to 9, 10 or more microbleeds) so both have a similar mix. The paper does not report patient age, sex, diagnoses or whether any patient contributed more than one exam.

Acquisition

All exams are GE SWAN (susceptibility-weighted angiography) from routine clinical practice on five GE systems: Discovery MR750w, Optima MR450w, Signa HDxt, Signa Architect and Signa Voyager, at 1.5 T and 3 T. In-plane resolution is 0.43 to 0.51 mm (median 0.47 mm) and slice spacing 0.8 to 1.4 mm (median 1.0 mm). The count per field strength is not given.

Annotations

An experienced neurologist drew voxel-wise masks of every microbleed between 2 and 10 mm in diameter on the SWAN images. Negative exams were checked to contain no visible microbleeds and have no masks.

Known limitations

• Not publicly available. The code repository asks interested researchers to contact the corresponding author about collaboration; no data terms are published.
• One annotator, single hospital, one vendor.
• No demographic or clinical information is reported.