Optimising diffusion weighted MRI for imaging metastatic and myeloma bone disease and assessing reproducibility

Eur Radiol. 2011 Aug;21(8):1713-8. doi: 10.1007/s00330-011-2116-4. Epub 2011 Apr 7.

Abstract

Objectives: To establish normal bone marrow values of apparent diffusion coefficient (ADC) over an age range, compare them with metastatic and myelomatous involvement, to establish reproducibility and to optimise b values.

Methods: The ADCs of bone marrow in 7 volunteers (mean age 29.7 years), 34 volunteers (mean age 63.3 years) and 43 patients with metastatic and myelomatous involvement (mean age 65.5 years) were measured. In 9 volunteers diffusion weighted MRI was repeated within 7 days. b values were derived to optimise contrast between normal and pathological marrow.

Results: The mean ADC of bone marrow in younger volunteers was significantly higher than that of older volunteers. The coefficient of reproducibility was 14.8%. The ADC mean of metastatic and myeloma bone disease was 1054 + / -456 x 10⁻⁶mm²s⁻¹. An ADC threshold of 655 × 10(-6) mm(2)s(-1) separated normal and abnormal marrow with a sensitivity and specificity of 90% and 93% respectively. Contrast between normal and abnormal marrow was optimal at b = 1389 smm(-2).

Conclusion: The reproducibility of ADC measurements in bone is equivalent to published data for soft tissue with a high sensitivity and specificity for separating abnormal from age matched normal bone marrow. A b value of around 1,400 smm(-2) is optimal for imaging bone marrow.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Bone Marrow / pathology*
  • Bone Marrow Neoplasms / pathology*
  • Bone Neoplasms / pathology*
  • Case-Control Studies
  • Diffusion Magnetic Resonance Imaging / methods*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Multiple Myeloma / pathology*
  • Prospective Studies
  • ROC Curve
  • Reproducibility of Results
  • Sensitivity and Specificity