2025 Volume 53 Issue 6 Pages 643-650
We attempted to determine muscle biopsy sites using fusion imaging technology, which synchronizes ultrasonography (US) examination with MRI images. [Method] We performed MRI and US in the biopsy position immediately prior to the biopsy. The MRI imaging technique used was fat-suppressed T2-weighted imaging, performed with markers affixed to the target muscle for the biopsy. US was aligned with MRI at the marker site to perform US/MRI fusion. The biopsy site was designated as the area with abnormal findings on MRI. After marking the site with ultrasound, an open muscle biopsy was performed directly beneath the marked site. [Results and Discussion] The muscle biopsy was performed on the quadriceps femoris and triceps brachii. The histopathological findings in both cases were consistent with myositis, and we successfully obtained tissue samples appropriate for diagnosis. In the triceps brachii, the MRI abnormalities were localized, but the lesion could be accurately identified. US is influenced by the examiner’s skill in scanning techniques and interpreting findings, but synchronizing it with MRI enables objective evaluation. Fusion imaging of US and MRI is expected to improve the diagnostic accuracy of muscle biopsy.
