From the Guidelines
Osteoporosis MRI findings typically include decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images in affected bone marrow, reflecting the replacement of normal fatty marrow with more water-containing tissue as bone mineral density decreases. When assessing vertebral compression fractures (VCFs) in patients with a history of malignancy or atypical clinical features, MRI is imperative for detecting early metastases and differentiating benign from malignant fractures, as osteoporotic VCFs can occur in patients with malignancy 1. Some key MRI findings in osteoporosis include:
- Decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images in affected bone marrow
- Bone marrow edema, which may indicate areas of active bone remodeling or microfractures
- Vertebral bodies often show decreased height and altered contour, with endplate deformities and compression fractures being common findings
- Acute fractures appear as areas of low signal on T1 and high signal on T2 and STIR sequences, while chronic fractures may show a dark signal on all sequences due to sclerosis
- Preservation of normal marrow signal adjacent to the fracture line, which is typically seen in osteoporotic fractures and can help distinguish them from pathological fractures caused by malignancy 1. MRI is particularly valuable for evaluating complications such as fractures and for ruling out other causes of bone pain or fractures in patients with known or suspected osteoporosis, and it allows assessment of the degree of thecal sac or cord compression, epidural extension, paraspinal extension, presence of other lesions, and vascularity 1.
From the Research
Osteoporosis MRI Findings
- Osteoporosis is related to changes in vertebral bone marrow tissues, which can be detected by MRI 2
- A novel MRI scoring method based on routine T1 and T2 sequences has been developed to detect osteoporosis and discriminate vertebral fractures 2
- The scoring method uses the patient's low-back subcutaneous fat and cerebrospinal fluid as reference controls to indicate proton-rich changes in vertebrae for assessing osteoporosis and vertebral fractures 2
- MRI can detect age- or osteoporosis-related changes in bone marrow tissues, making it a promising tool for assessing osteoporosis 2
MRI Scoring Method
- The F-scoresc.fat and W-scorecs.fluid increased significantly in patients with osteoporosis compared to non-osteoporosis 2
- Receiver operating characteristic (ROC) analysis indicated that F-scoresc.fat had a greater AUC value than VBQ score and SNRL1-L5 when used to detect osteoporosis 2
- F-scoresc.fat resulted in the largest AUC value when separating vertebral fractures from non-fractures, compared to W-scorecs.fluid, VBQ, and SNRL1-L5 2
Other Imaging Modalities
- Dual-energy X-ray absorptiometry (DXA) has been the clinical reference standard for diagnosing osteoporosis and assessing fracture risk 3
- Quantitative magnetic resonance imaging (MRI) methods, such as trabecular bone microstructure analysis and T2 * mapping, can provide valuable information on osteoporotic fracture risk 3
- Magnetic resonance spectroscopy (MRS) and chemical shift encoding-based water-fat MRI (CSE-MRI) enable the quantitative assessment of the nonmineralized bone compartment through extraction of the bone marrow fat fraction (BMFF) 3