AnalyzeDirect Holly L. Stewart et al. Experimental models of bone marrow lesions in ovine femoral condyles Veterinary Surgery.
Publication Date
December 15, 2022
How Analyze was Used
“For CNR, the signal of the ROI of the muscle was subtracted from the signal in the ROI of the BML, and then divided by the standard deviation of the background air ROI. Baseline SNRs and CNRs were calculated in the same locations as the postoperative BML by overlying postoperative MR images from all sequences (AnalyzeDirect, version 14.0, Overland Park, Kansas).
A 3 mm2 circular ROI was used to evaluate the attenuation in Hounsfield Units (HU) within the BML on CT images obtained using the bone reconstruction kernel at 140 kVp. MR images were overlaid onto CT images to determine the location of the BML. If the BML extended beyond 3 mm2 and the pin tract was visible, the ROI was placed adjacent to the pin tract, but excluded cortical bone. Multiplanar reconstruction was used to identify a similar location within the lateral femoral condyle of the same limb to grade the attenuation. In limbs where a BML was not visible on MR images, but a BML was present in the contralateral limb, the contralateral limb was overlaid to identify a region of interest to grade the attenuation. In cases where a BML was not visible on either limb, MR images from another animal with a BML were used to identify a region of interest to grade the attenuation to ensure a similar area was used for evaluation in all limbs.”
Keywords
Experimental models, Bone marrow lesions, Ovine femoral condyles
Author Affiliation(s)
Colorado State University, Fort Collins, Colorado, USA
