Quantitative analysis of vertebral bone marrow perfusion using dynamic contrast‐enhanced MRI: Initial results in osteoporotic patients with acute vertebral fracture

Abstract

Purpose: To evaluate the potential of quantitative dynamic contrast-enhanced MRI (DCE-MRI) in vertebral bone marrow (vBM) of patients with acute osteoporotic vertebral compression fractures. Materials and Methods:Twenty-six patients with acute osteoporotic fractures (16 female, 10 male, median age 72, range 48-89) and 10 subjects without known history of osteoporosis (6 female, 4 male, median 65, range 31-77) were examined 2D-DCE-MRI. Region of interest (ROI) data in fractured (n ¼ 26) and normal-appearing vertebrae (n ¼ 271) were analyzed with a two-compartment tracer-kinetic-model, providing estimates of at least three independent parameters: plasma flow (PF), plasma volume (PV), and extraction flow (EF). Parameters were correlated with dual x-ray absorptiometry (DXA) (n ¼ 15) and quantitative computed tomography (QCT) densitometry (n ¼ 10).Results: Mean PF was significantly higher in fractures than in normal-appearing vertebrae (69.37 vs. 11.72 mL/ 100 mL/min). Similarly, mean PV and EF differed significantly. Mean PF was significantly decreased in normalappearing vBM osteoporotic patients compared to the control group. Mean PF and PV were significantly decreased in lumbar compared to thoracic vertebrae. PV showed a significant correlation with QCT.Conclusion: Perfusion parameters were decreased significantly in normal-appearing vBM of patients. Furthermore, significant perfusion alterations were observed in acute osteoporotic vertebral fractures compared to normalappearing vertebrae.

Quantitative MRI and spectroscopy of bone marrow

“…Quantitative analysis requires the additional measurement of an arterial input function and a tracer kinetic analysis to derive perfusion and permeability parameters. Previous works have primarily employed semiquantitative analysis on bone marrow DCE data and there are only a few studies using quantitative analysis tools and especially addressing the effect of the presence of the fat signal on the extracted perfusion metrics …”

Quantitative imaging methods in osteoporosis

“…Furthermore, maximum enhancement [E(max)] and enhancement slope [E(slope)] are significantly decreased in osteoporosis in at least the femurs and vertebrae (114)(115)(116)(117)(118). Quantitative parameters of blood flow were studied with DCE-MRI in osteoporotic patients with acute vertebral fracture compared to a control group (119). Plasma flow (mL/100 mL/min) quantifies the volume of plasma flowing through the region of interest per unit time; plasma volume (mL/100 mL) corresponds to the volume of the plasma per tissue volume in the region of interest and extraction flow (mL/100 mL/min) characterizes the net flow between the plasma and the interstitial space (extracellular and extravascular space).…”

Quantitative Dynamic Contrast-Enhanced MRI of Pelvic and Lumbar Bone Marrow: Effect of Age and Marrow Fat Content on Pharmacokinetic Parameter Values

“…Although use of population-derived arterial input function showed improved reproducibility in at least one study of 23 cancer patients [26], an automated technique was shown to be superior to both population-based arterial input function and placement of ROI on a major artery [27,28]. The presence or absence of osteoporosis or osteopenia within subjects was not specifically addressed and has been shown to have a significant effect on quantitative perfusion parameters [29]. This is a confounding factor with respect to age and may skew results toward a generalized decrease in kinetic parameter values with age secondary to a common pathologic process.…”