Bone mineral density measurement in children and adolescents: Novelties in measurement programs
Novelties in measurement programs
Speed of measurement by densitometric techniques in children is of great importance, because it is hard to keep children motionless during the performance. However, utilization of speeding up measurement as fan beam technique has still some disadvantages enforcing the needs of its further evaluation and cross-calibration. For accurate determination of bone mineral accrual in growing subjects with the use of DXA correction of all magnification errors is needed. Children with growth abnormalities often show deficient BMD for chronological age. That might be a reflection of growth irregularities rather than poor bone mineralization. Taking on account body size deficit, improves significantly the assessment of bone status in children. In the newest software for DXA appeared the possibility of adjusting body size using three-step assessment: height for age, BMC for height and bone area for height. Moreover, incorporation of the variable standard deviations in DXA pediatric reference data results in more accurate assessment of pedi- atric skeletal health; what is especially ortant during pubertal growth spurt. The other prospective technical improvements are related to incorporation of reference ranges for subcranial BMD and normalization of skeletal status with the use of muscle mass adjustment.
Summing up the following points should be specially underlined. In children data evaluation exclusively Z-scores should be used. The diagnosis of osteoporosis in children should be not only limited to densitometric criteria. In diagnostic, helpful are the factors like bone geometry, bone size, pubertal stage, skeletal maturity, and body composition. Terminology such as “low bone density for chronological age” may be used when the Z-score is below -2.0, with spine and total body usage as preferred skeletal sites for measurement. Serial BMD studies should be done on the same machine using the same scanning mode and software. Such a way of thinking is steadily executed in general practice. It is also supported by International Society for Clinical Densitometry (ISCD) published in November 2003 in their position statement. Suffer no more! Buy ventolin inhaler online at a price you can afford.