Background: Recent developments in diagnostic imaging techniques have magnified the role and potential of MRI in patients with multiple myeloma. Quantitative diffusion-weighted imaging of the bone marrow is adjunct tool for the diagnosis of a diffuse MR imaging pattern in patients with multiple myeloma.
Aim of the Work: This study aimed to evaluate the apparent diffusion coefficients (ADCs) of magnetic resonance (MR) imaging patterns in the bone marrow of patients with multiple myeloma (MM) and to determine a threshold ADC that may help distinguish a diffuse from a normal pattern with high accuracy
Patients and Methods: This study was carried out in Radiology Department of Ain Shams University Hospitals. This study included 30 patients newly diagnosed, untreated MM and 16 healthy control subjects underwent spinal MR imaging including diffusion-weighted imaging, and bone marrow ADCs were calculated. Pattern assignment was based on visual assessment of conventional MR images.
Results: Mean ADCs 6 standard deviation in patients with MM for the normal, focal, and diffuse MR imaging patterns were 0.360 x 10-3 mm2/sec +/- 0.110, 1.046 x 10-3 mm2/sec +/- 0.232, and 0.770 x 10-3 mm2/sec +/- 0.135, respectively. There were significant differences in ADCs between diffuse and normal (P .001), diffuse and focal (P.001), and focal and normal (P.001) patterns. Patients with a diffuse pattern had more features of advanced disease, higher international staging system score, increased incidence of high-risk cytogenetics, and higher revised international staging system score. ADCs greater than 0.548 x 10-3 mm2/sec showed 100% sensitivity (9 of 9) and 98% specificity (10 of 11) for the diagnosis of a diffuse (vs normal) MR imaging pattern, whereas an ADC greater than 0.597 x 10-3 mm2/sec showed 100% sensitivity (9 of 9) and 100% specificity.
Conclusion: ADCs of MR imaging patterns in patients with MM differ significantly. A diffuse MR imaging pattern can be distinguished more objectively from a normal MR imaging pattern by adding quantitative diffusion-weighted imaging to standard MR imaging protocols.