Keywords:
Osteoporosis, Statistics, Imaging sequences, MR, Absorptiometry / Bone densitometry, Neuroradiology spine, Musculoskeletal spine
Authors:
R. Laqua, R. Kayser, S. Ostrzinski, N. Hosten, J.-P. Kühn, R. Puls, K. Hegenscheid; Greifwald/DE
DOI:
10.1594/ecr2012/C-2616
Results
DEXA
Mean BMD was 1.04,
1.13,
1.21,
and 1.23 g/cm2 in lumbar vertebra (LV) 1 to LV4 respectively.
Intra- & Interreader Variability
The intrareader variability analysis showed that each reader on his own managed to produce reliable values (table 1),
while the interreader variability of L1 and L2 exceeds our self set goal of a mean bias below 5% (table 2).
Meaning it is hard to reproduce R2* values between multiple readers when measuring L1 and L2.
A methodological problem has to be assumed,
and the use of these values has to be reconsidered.
As a consequence all R2* values were measured by one reader alone.
Magnetic Resonance Imaging
Mean R2* decreased from 17.90 in L1 to 17.51,
17.45,
16.66,
and 16.46 in L2,
L3,
L4,
and L5,
respectively.
Figure 3 shows the best correlation that was found for a single vertebra (r = 0.3445; p < 0.05).
When R2* averages or maximum R2* values were compared with minimum BMD,
correlation improved.
As shown in figure 4 the correlation was best between maximum R2* and minimum BMD (r = 0.4803; p < 0.0005).
The expected decrease of R2* values with age did not reach statistical significance (p < 0.1).
Figure 5 demonstrates the most reliable measurements of R2* value in comparison to age.