Keywords:
Bones, Musculoskeletal bone, Musculoskeletal system, Absorptiometry / Bone densitometry, CT-High Resolution, CT-Quantitative, Diagnostic procedure, Technical aspects, Demineralisation-Bone, Dysplasias, Genetic defects
Authors:
S. Gazzotti, R. Sassi, M. P. Aparisi Gomez, E. Schileo, F. Taddei, E. Brizola, L. Sangiorgi, M. Miceli, A. Bazzocchi
DOI:
10.26044/ecr2024/C-18685
Methods and materials
This ongoing prospective study (target = 40 subjects) includes children (> 8 years of age) and adults with OI. Exclusion criteria encompass presence of metallic hardware that impedes adequate scanning, inability to remain immobile for the time required for scanning, pregnancy, and bone loss induced by medications. DXA scans (Hologic QDR Discovery Wi) are performed at the lumbar spine, hip, total body, and non-dominant forearm, following recommendations from the manufacturer and relevant international guidelines [12, 13]. Second-generation HR-pQCT (XtremeCT II, SCANCO Medical) scans are acquired at the non-dominant distal radius and tibia, with a fixed offset protocol, in accordance with recommendations from the manufacturer and recent guidelines [14]. HR-pQCT images are analysed via automatic contouring with the standard XtremeCT II evaluation algorithm incorporated in the machine. The use of HR-pQCT in OI is off-label (approval of Ethics Committee was obtained). For the purpose of the present preliminary analysis, the following parameters were taken into consideration:
- DXA: aBMD at L1-4, total hip, femoral neck, 1/3 radius, ultradistal radius, and total body
- HR-pQCT: total vBMD (Tt.vBMD), cortical vBMD (Ct.vBMD), trabecular vBMD (Tb.vBMD), trabecular bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), standard deviation of 1/Tb.N as a measure of trabecular inhomogeneity (Tb.1/N.SD), cortical thickness (Ct.Th), total area (Tt.Ar), trabecular area (Tb.Ar), and cortical area (Ct.Ar)
Associations between DXA-aBMD and HR-pQCT parameters were assessed via the Pearson’s correlation coefficient (r), using Stata/SE 17.0. Statistical significance was set at p < 0.05.