This article is more than 5 years old. Information may no longer be current.
CAS likely effective in detecting changes in bone marrow lesions
Compared with an MRI segmentation method for measuring bone marrow lesions, study findings showed a computer-assisted method was reliable and more sensitive for detecting changes over time.
Researchers performed MRI on 22 patients with knee osteoarthritis (OA) confined to the medial femoro-tibial compartment at baseline and follow-up. Using a 1.5 T system, the researchers obtained short tau inversion recovery (STIR), T1 and fat saturated T1 post-contrast sequences, assessing the 44 sagittal STIR sequences independently for quantification of bone marrow lesions (BML). The researchers also used the signal intensities (SIs) of normal bone marrow in the lateral femoral condyles and tibial plateaus as threshold values and measured the volume of bone marrow with SIs exceeding the threshold in the medial femoral condyle and tibial plateau and related to the total volume of the condyles/plateaus. The sensitivity to change was determined by 95% limits of agreement at baseline.
Although similar mean threshold values were observed for both the computer-assisted (CAS) and manual (MS) methods, results showed differences in the absolute and relative BML volumes, with an average median BML volume in the femur of 1,319 mm3 using the CAS method vs. 1,828 mm3 using the MS method, and average median BML volumes in the tibia of 941 mm3 using the CAS method vs. 2,097 mm3 using the MS method.
The researchers found a significant correlation between BML volumes obtained by CAS and MS; however, differences in the measurement of tissue changes were observed.
CAS measured the volume of voxels exceeding the threshold values, whereas MS included intervening voxels with normal SI, according to the researchers.
Overall, CAS had narrower 95% limits of agreement vs. MS, and BML changed significantly in 13 knees using CAS and in 10 knees using MS. – by Casey Tingle
Disclosure: The researchers report no relevant financial disclosures.