Evaluation of the possibility to assess bone age on the basis of DXA derived hand scans?preliminary results

Abstract

The classical method of skeletal age assessment is based on the recognition of changes in the radiographic appearance of the maturity indicators in hand-wrist radiographs by comparison with a reference atlas. The purpose of this study was the evaluation of the possibility to assess bone age using a less invasive method such as dual-energy X-ray absorptiometry (DXA). Bone ages of 50 children free of any chronic diseases (5-18 years old) and ten with multihormonal pituitary deficiency (MPD) (8-20 years old) were assessed using an Expert-XL densitometer. Hand scans and classical hand-wrist radiographs were evaluated by two independent observers for bone age by visual comparison with reference standards of skeletal development published in the atlas. The precision errors of duplicate bone age ratings were low both for radiographs (<1%) and DXA hand scans (<0.9%). A high degree of agreement between bone age ratings done by two observers was assessed by intraclass correlation coefficients. The same bone age based on radiographs and DXA hand scans was assessed in 44 of 60 cases (73.3%); in 16 cases the differences between bone age were no higher than 0.5 year. No significant difference between mean bone age based on radiographs and DXA hand scans was observed ( P>0.05). Moreover, there was a very strong correlation between bone age results ( r=0.998; r(2)=0.996; P<0.0001), indicating agreement of bone age assessments based on DXA and radiographic images. Remarkable differences (up to 3 years) between bone age and chronological age were observed in healthy subjects, probably reflecting the effect of the secular trend towards earlier maturation or alterations in pubertal development. The study indicates that evaluation of skeletal maturity using DXA images is less invasive (up to 8 micro Sv) than radiography, giving results comparable to the classical method.

Accelarated Skeletal Maturation in Children With Primary Hypertension

“…When the appearances lay between 2 standards, a BA between these was given with the precision of 0.5 years. 9,15 The intraobserver variability calculated on the basis of duplicate BA estimations of 50 hand scans was 0.88% for the observer involved in the present study. On the basis of recommendations of our atlas, the rates of maturation in terms of "physiological," "accelerated," and "delayed" BA were defined as follows: differences between BA and CA ranging between Ϫ0.9 to ϩ0.9 were considered as physiological, BA-CA below Ϫ0.9 as delayed skeletal maturation, and BA-CA above ϩ0.9 as accelerated maturation.…”

“…14 -17 Specifically, the resolution of the handwrist image generated by the Expert-XL densitometer was 0.0025 cm 2 as an effect of fan-beam technology. 15 Standard procedures provided by the DXA manufacturer (ie, 1-mA fast, 134 kV) were used for measurements. The entrance surface dose was Յ8 Sv, equal to Ϸ1 day of background radiation in Poland.…”

Assessment of skeletal age on the basis of DXA-derived hand scans in elite youth soccer

“…Compared to X-ray, computerized axial tomography and magnetic resonance imaging, the main advantages of the DXA method are a high safety and significantly lower exposure to radiation (Coelho e Silva et al, 2013;Gordon et al, 2008). DXA-derived hand-wrist scans recently have become available and could be an approach to adjust for factors related to growth and puberty (Heppe et al, 2012;Płudowski, Lebiedowski, & Lorenc, 2004). Evaluating SA via hand-wrist radiographs using DXA produces one-tenth of the effective radiation dose (0.1 μSv) compared to X-rays (1 μSv) (Gordon et al, 2008;International Atomic Energy Agency [IAEA], 2006).…”

“…To the best of our knowledge, only two studies have investigated the agreement between DXA and X-ray hand-wrist imaging as methods for assessing SA (Heppe et al, 2012;Płudowski et al, 2004). The first study was performed in a paediatric population of 24 girls (age range: 5-17 years) and 26 boys (age range: 5-20 years).…”

Abschätzung des Knochenalters mit einer neuen Ultraschallmethode

“…B. der Handscan der Dual-energy X-ray Absorptiometry (DXA) zur Knochenaltersbestimmung verwendet werden, bei der die Belastung lediglich noch ca. 8 µSv beträgt [17,18]. Völlig frei von ionisierender Strahlung sind sonographische Techniken zur Knochenaltersbestimmung [19 -23].…”