Feasibility of assessing male osteoporosis using MRI IDEAL-IQ sequence of proximal femur in prostate cancer patients

Figures & data

Figure 1. MR images show PDFF (a) and R2* (b) of proximal femur measured in a 76-year-old man with prostate cancer. ROI is manually traced from the femoral head to the horizontal line of the lower end of the lesser trochanter to calculate R2* value and PDFF. PDFF: proton density fat fraction; ROI: region of interest.

As an actual measurement of R2* and PDFF using MRI IDEAL-IQ sequence, this figure shows the region of interest in the proximal femur of a prostate cancer patient.

Table 1. Clinical characteristics of study population.

	Overall patients	BMD T-score ≤ –2.5	BMD T-score > –2.5	p Value
N (%)	104 (100)	14 (13.5)	90 (86.5)
Age (years)	76.6 (71.6–80.3)	79.0 (76.6–85.0)	75.9 (71.2–80.1)	0.0336
Body height (m)	1.7 (1.6–1.7)	1.7 (1.6–1.7)	1.7 (1.6–1.7)	0.6061
Weight (kg)	64.4 (58.0–70.0)	58.5 (53.2–66.3)	65.0 (59.6–70.4)	0.0503
BMI (kg/m^2)	23.4 (21.8–24.9)	22.5 (20.2–23.8)	23.6 (22.3–26.1)	0.0379
Total hip BMD (g/cm^2)	0.88 (0.78–1.0)	0.67 (0.62–0.70)	0.92 (0.82–1.0)	<0.0001
Total hip BMD T-score	−1.3 (−2.0 to −0.4)	−2.8 (−3.2 to −2.5)	−0.9 (−1.7 to −0.28)	<0.0001
MRI IDEAL-IQ data
R2* (s^−1)	53.9 (50.7–57.8)	48.8 (46.5–51.0)	54.9 (51.8–58.1)	0.0001
PDFF	83.8 (80.0–86.4)	84.7 (82.4–86.7)	83.6 (79.6–86.4)	0.3913

Data are denoted by median (IQR). Differences between the groups were determined by the Wilcoxon rank sum test.

BMD: bone mineral density; BMI: body mass index; IDEAL-IQ: iterative decomposition of water and fat with echo asymmetry and least square estimation; IQR: interquartile range; PDFF: proton density fat fraction.

Figure 2. Spearman’s rank correlation coefficient between BMD (g/cm²), MRI-based R2* value (a) and PDFF (b) in proximal femur. R2* values were significantly correlated with BMD compared with PDFF in prostate cancer patients. BMD: bone mineral density; PDFF: proton density fat fraction.

This figure shows Spearman’s rank correlation coefficient, where R2* values were significantly correlated with BMD compared to PDFF in prostate cancer patients.

Figure 3. AUC of R2* for distinguishing BMD-T score ≤ −2.5 and > −2.5 was estimated to be 0.817, with cut-off values of 50.7 s⁻¹. AUC: area under the curve; BMD: bone mineral density.

This figure shows ROC analysis, and the area under the curve value of R2* for distinguishing BMD-T score ≤ −2.5 and > −2.5 was estimated to be 0.817.