Role of growth hormone in enchondroplasia and chondral osteogenesis: evaluation by X-ray of the hand

Performance of an artificial intelligence system for bone age assessment in Tibet

OBJECTIVE

To investigate whether bone age (BA) of children living in Tibet Highland could be accurately assessed using a fully automated artificial intelligence (AI) system.

METHODS：

Left hand radiographs of 385 children (300 Tibetan and 85 immigrant Han) aged 4-18 years who presented to the largest medical center of Tibet between September 2013 and November 2019 were consecutively collected. From these radiographs, BA was determined using the Greulich and Pyle (GP) method by experts in a consensus manner; furthermore, BA was estimated by a previously reported artificial intelligence (AI) BA system based on Han children from southern China. The performance of the AI system was compared with that of experts by using statistical analysis.

RESULTS

Compared with the experts' results, the accuracy of the AI system for Tibetan and Han children within 1 year was 84.67 and 89.41%, respectively, and its mean absolute difference (MAD) was 0.65 and 0.56 years, respectively. The discrepancy in hand-wrist bone maturation was the main cause of low accuracy of the system in the 4- to 6-year-old group.

CONCLUSION

The AI BA system developed for Han Chinese children living in flat regions could enable to assess BA accurately in Tibet where medical resources are limited.

ADVANCES IN KNOWLEDGE

AI-based BA system may serve as an effective and efficient solution to assess BA in Tibet.

GH Dose Reduction Maintains Normal Prepubertal Height Velocity After Initial Catch-Up Growth in Short Children

CONTEXT

GH responsiveness guides GH dosing during the catch-up growth (CUG) period; however, little is known regarding GH dosing during the prepubertal maintenance treatment period.

OBJECTIVE

To evaluate whether SD score (SDS) channel parallel growth with normal height velocity can be maintained after CUG by reducing the GH dose by 50% in children receiving doses individualized according to estimated GH responsiveness during the catch-up period.

DESIGN AND SETTINGS

Prepubertal children (n = 98; 72 boys) receiving GH during CUG (GH deficient, n = 33; non-GH deficient, n = 65), were randomized after 2 to 3 years to either a 50% reduced individualized dose (GHRID; n = 27; 20 boys) or unchanged individualized dose (GHUID; n = 38; 27 boys). Another 33 children (25 boys) continued a standard weight-based dose [43 µg/kg/d (GHFIX)].

MAIN OUTCOME MEASURES

The primary endpoint was the proportion of children with ΔheightSDS within ±0.3 at 1 year after GH dose reduction compared with two control groups: GHUID and GHFIX. The hypothesis was that heightSDS could be maintained within ±0.3 with a reduced individualized GH dose.

RESULTS

For the intention-to-treat population at 1 year, 85% of the GHRIDgroup maintained ΔheightSDS within ±0.3 vs 41% in the GHUIDgroup (P = 0.0055) and 48% in the GHFIXgroup (P = 0.0047). The ΔIGF-ISDS in the GHRID group was -0.75 ± 1.0 at 3 months (P = 0.003) and -0.72 ± 1.2 at 1 year compared with the GHUID group (0.15 ± 1.2; P = 0.005) and GHFIX group (0.05 ± 1.0; P = 0.02).

CONCLUSIONS

Channel parallel growth (i.e., normal height velocity) and IGF-ISDS levels within ±2 were maintained after completed CUG using a 50% lower individualized dose than that used during the CUG period.

Hand MRI and the Greulich-Pyle atlas in skeletal age estimation in adolescents

OBJECTIVE

To evaluate the feasibility of hand MRI in age assessment in adolescents using the Greulich-Pyle (GP) atlas criteria.

MATERIALS AND METHODS

Two radiologists, who were blinded to the study subjects' chronologic ages, semi-objectively evaluated 1.5-T MRIs of the left hands of ten patients (13.5 ± 2.6 years) who had left-hand radiographs and 50 healthy volunteers (15 ± 2 years).

RESULTS

A coronal T1-weighted, volumetric, interpolated, breath-hold examination with water excitation (T1 VIBE-3D-WE) achieved the best image quality. The correlation between estimated patients' ages on radiographs and MRI was high. The average estimated age difference between the MRIs and radiographs was -0.05 years for reader 1 and -0.175 years for reader 2. The interclass coefficients (ICCs) showed high interobserver agreement (radiographs: ICC = 0.95, MRI: ICC = 0.97). The ICC, calculated separately for the male and female volunteers' estimated ages by MRI, also showed a high agreement between the two readers (male: ICC = 0.97, female: ICC = 0.95). Reader 1 estimated 94% of volunteers within 2 standard deviations (SD) and 62% within 1 SD. The results for reader 2 were 92% and 54%, respectively. Thirty-nine percent of girls and 27% of boys were estimated to be older using 1 SD.

CONCLUSION

MRI of the left hand is a feasible alternative to hand radiographs for skeletal age estimation in adolescents using the GP criteria with 2 SD. Using 1 SD, the age of healthy volunteers tended to be estimated as higher than the chronologic age. Future studies should evaluate the results in a larger number of participants.

Relationship between velvet antler ossification and PTH and androgen serum levels in Tarim Red deer (Cervus elaphus)

Ossification degree is one of the primary variables affecting the medicinal value of velvet antler. Multiple factors regulate the calcification of velvet antler. We studied the relationship between the ossification of velvet antlers and the serum levels of parathyroid hormone (PTH) and androgen (ADG) in Tarim red deer. Enzyme-linked immunosorbent assays (ELISA) and atomic absorption spectrometry demonstrated that the changes in serum PTH and ADG levels nearly paralleled antler ossification during Tarim red deer antler mineralization. These results suggest that regulating the levels of serum PTH and ADG could decrease the calcification rate of velvet antlers in Tarim red deer. We conclude that PTH might increase antler ossification via the cAMP signaling pathway, and ADG possesses the dual roles of promoting both antler ossification and growth in Tarim red deer. This study suggests that we might be able to artificially control antler ossification to improve its medical value via the PTH or/and ADG pathway. J. Exp. Zool. 323A: 696-703, 2015. © 2015 Wiley Periodicals, Inc.