Accuracy of skeletal age assessment in children from birth to 6 years of age with the ultrasonographic version of the Greulich-Pyle atlas

Bone age assessment based on three-dimensional ultrasound and artificial intelligence compared with paediatrician-read radiographic bone age: protocol for a prospective, diagnostic accuracy study

INTRODUCTION

Radiographic bone age (BA) assessment is widely used to evaluate children's growth disorders and predict their future height. Moreover, children are more sensitive and vulnerable to X-ray radiation exposure than adults. The purpose of this study is to develop a new, safer, radiation-free BA assessment method for children by using three-dimensional ultrasound (3D-US) and artificial intelligence (AI), and to test the diagnostic accuracy and reliability of this method.

METHODS AND ANALYSIS

This is a prospective, observational study. All participants will be recruited through Paediatric Growth and Development Clinic. All participants will receive left hand 3D-US and X-ray examination at the Shanghai Sixth People's Hospital on the same day, all images will be recorded. These image related data will be collected and randomly divided into training set (80% of all) and test set (20% of all). The training set will be used to establish a cascade network of 3D-US skeletal image segmentation and BA prediction model to achieve end-to-end prediction of image to BA. The test set will be used to evaluate the accuracy of AI BA model of 3D-US. We have developed a new ultrasonic scanning device, which can be proposed to automatic 3D-US scanning of hands. AI algorithms, such as convolutional neural network, will be used to identify and segment the skeletal structures in the hand 3D-US images. We will achieve automatic segmentation of hand skeletal 3D-US images, establish BA prediction model of 3D-US, and test the accuracy of the prediction model.

ETHICS AND DISSEMINATION

The Ethics Committee of Shanghai Sixth People's Hospital approved this study. The approval number is 2022-019. A written informed consent will be obtained from their parent or guardian of each participant. Final results will be published in peer-reviewed journals and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200057236.

Skeletal and dental age estimation via postmortem computed tomography in Polish subadults group

This article is a retrospective analysis of postmortem computed tomography scans of ossification stages of the anterior and posterior intra-occipital sutures, the anterior arch of the atlas, and the neurocentral junction of the axis. We also analyzed the development of secondary ossification centers in the proximal humeral, femoral, and tibial epiphyses, and the distal femoral and tibial epiphyses. Additionally, the development of primary ossification centers in the wrist and metacarpals, and maxillary and mandibular deciduous tooth maturation. A total of 58 cadavers (35 males, 23 females), whose age ranged from 3rd month of pregnancy to 14 years, were analyzed. The results of this study show that analysis of synchondrosis closure, primary, and secondary ossification center development and deciduous tooth changes are a good tool for age estimation in subadults group (fetuses, newborns, infants, and children). The results of the study in a Polish population are consistent with those reported by other authors.

Texture Analysis for the Bone Age Assessment from MRI Images of Adolescent Wrists in Boys

Currently, bone age is assessed by X-rays. It enables the evaluation of the child's development and is an important diagnostic factor. However, it is not sufficient to diagnose a specific disease because the diagnoses and prognoses may arise depending on how much the given case differs from the norms of bone age.

BACKGROUND

The use of magnetic resonance images (MRI) to assess the age of the patient would extend diagnostic possibilities. The bone age test could then become a routine screening test. Changing the method of determining the bone age would also prevent the patient from taking a dose of ionizing radiation, making the test less invasive.

METHODS

The regions of interest containing the wrist area and the epiphyses of the radius are marked on the magnetic resonance imaging of the non-dominant hand of boys aged 9 to 17 years. Textural features are computed for these regions, as it is assumed that the texture of the wrist image contains information about bone age.

RESULTS

The regression analysis revealed that there is a high correlation between the bone age of a patient and the MRI-derived textural features derived from MRI. For DICOM T1-weighted data, the best scores reached 0.94 R2, 0.46 RMSE, 0.21 MSE, and 0.33 MAE.

CONCLUSIONS

The experiments performed have shown that using the MRI images gives reliable results in the assessment of bone age while not exposing the patient to ionizing radiation.

Evaluation of distal femoral and proximal tibial epiphyseal plate in bone age estimation with 3.0T MRI: a comparison of current methods

OBJECTIVE

Dedouit et al, Kramer et al and Vieth et al defined different staging methods over different sequences in knee MRI for bone age determination. Our study aims to examine three different methods in which the maturation stages of the knee epiphyses are evaluated by MRI in the same population, to compare the methods and results and evaluate them for some age thresholds and to discuss their applicability in forensic age estimation.

METHODS

In this study, 597 knee images obtained using a 3.0T MR scanner were evaluated retrospectively. The T 1 weighted and proton density-weighted sequences were evaluated by two observers. Knee bone development was staged on the femur and tibia, and descriptive statistics were calculated for each stage according to age and sex. Descriptive statistics were presented according to the age and sex of the cases, and intra- and interobserver agreements were evaluated by the κ and κw statistics obtained by the Fleiss approach.

RESULTS

Significant changes were found in stages depending on age. The intra- and interobserver agreement levels were very good (κ > 0.80) for each method. The methods of Dedouit, Kramer and Vieth can be used as an additional criteria for forensic age estimation for 14, 15, 18 and 21 year thresholds.

CONCLUSION

Knee MRI stands out as an alternative modality for age estimation and it is necessary to prefer the method intended for the investigated age range with an individual-specific approach.

ADVANCES IN KNOWLEDGE

Our study stands out as the first study in which current classification methods were applied and compared in the same population for age estimation with knee MRI.

Pediatric age estimation from thoracic and abdominal CT scout views using deep learning

Age assessment is regularly used in clinical routine by pediatric endocrinologists to determine the physical development or maturity of children and adolescents. Our study investigates whether age assessment can be performed using CT scout views from thoracic and abdominal CT scans using a deep neural network. Hence, we retrospectively collected 1949 CT scout views from pediatric patients (acquired between January 2013 and December 2018) to train a deep neural network to predict the chronological age from CT scout views. The network was then evaluated on an independent test set of 502 CT scout views (acquired between January 2019 and July 2020). The trained model showed a mean absolute error of 1.18 ± 1.14 years on the test data set. A one-sided t-test to determine whether the difference between the predicted and actual chronological age was less than 2.0 years was statistically highly significant (p < 0.001). In addition, the correlation coefficient was very high (R = 0.97). In conclusion, the chronological age of pediatric patients can be assessed with high accuracy from CT scout views using a deep neural network.

[Radiological methods for age diagnostics : Clinical and forensic aspects]

Age diagnostics play an increasing role in radiology. Medical and forensic questions are indications for the application of age diagnostics. In addition to X‑rays of the hand in childhood, panoramic tomography and computed tomography are currently the standard procedures. Alternative modalities without ionizing radiation (sonography, magnetic resonance imaging) have not (yet) been established. The purpose of this article is to present the indications and methods of age diagnostics in the clinical and forensic contexts and to familiarize you with their advantages and disadvantages as well as the possibility of determining the final length.

Pediatric age estimation from radiographs of the knee using deep learning

OBJECTIVES

Age estimation, especially in pediatric patients, is regularly used in different contexts ranging from forensic over medicolegal to clinical applications. A deep neural network has been developed to automatically estimate chronological age from knee radiographs in pediatric patients.

METHODS

In this retrospective study, 3816 radiographs of the knee from pediatric patients from a German population (acquired between January 2008 and December 2018) were collected to train a neural network. The network was trained to predict chronological age from the knee radiographs and was evaluated on an independent validation cohort of 423 radiographs (acquired between January 2019 and December 2020) and on an external validation cohort of 197 radiographs.

RESULTS

The model showed a mean absolute error of 0.86 ± 0.72 years and 0.9 ± 0.71 years on the internal and external validation cohorts, respectively. Separating age classes (< 14 years from ≥ 14 years and < 18 years from ≥ 18 years) showed AUCs between 0.94 and 0.98.

CONCLUSIONS

The chronological age of pediatric patients can be estimated with good accuracy from radiographs of the knee using a deep neural network.

KEY POINTS

• Radiographs of the knee can be used for age estimations in pediatric patients using a standard deep neural network. • The network showed a mean absolute error of 0.86 ± 0.72 years in an internal validation cohort and of 0.9 ± 0.71 years in an external validation cohort. • The network can be used to separate the age classes < 14 years from ≥ 14 years with an AUC of 0.97 and < 18 years from ≥ 18 years with an AUC of 0.94.

Traditional and New Methods of Bone Age Assessment-An Overview

Bone age is one of biological indicators of maturity used in clinical practice and it is a very important parameter of a child’s assessment, especially in paediatric endocrinology. The most widely used method of bone age assessment is by performing a hand and wrist radiograph and its analysis with Greulich-Pyle or Tanner-Whitehouse atlases, although it has been about 60 years since they were published. Due to the progress in the area of Computer-Aided Diagnosis and application of artificial intelligence in medicine, lately, numerous programs for automatic bone age assessment have been created. Most of them have been verified in clinical studies in comparison to traditional methods, showing good precision while eliminating inter- and intra-rater variability and significantly reducing the time of assessment. Additionally, there are available methods for assessment of bone age which avoid X-ray exposure, using modalities such as ultrasound or magnetic resonance imaging.

Statistical Confirmation of a Method of US Determination of Bone Age

Background There is limited literature on conventional US to assess bone age. Purpose To determine the diagnostic performance of US in the assessment of abnormal bone age in Chinese children. Materials and Methods In this prospective study, children and young adults aged between birth and 19 years from a large provincial teaching hospital were enrolled from January to November 2020. Children without clinical diseases potentially affecting skeletal growth were included in the normal-value group. Children with clinically suspected growth disturbances who were undergoing bone age evaluation were included in the validation group. Ossification ratios (ie, the ratio of the height of the epiphyseal ossification center to the entire epiphysis, including the cartilaginous component) of the radius, ulna, and femur from all the children were measured using US. Ultrasonic skeletal maturity scores (ie, the summation of ossification ratios of the radius, ulna, and femur multiplied by 100) collected from children in the normal-value group were used for score-for-age curve fitting through Box-Cox power exponential distribution. Test performance characteristics for the ability of US to help diagnose abnormal bone age were determined using radiographic bone age as a reference standard. Statistically significant difference between groups was determined by using a paired-sample t test. Results A total of 1089 children (median age, 9 years [interquartile range, 3-14 years]; 578 boys) were enrolled, including 929 children (mean age, 8 years [interquartile range, 4-12 years]; 515 boys) in the normal-value group and 160 children (mean age, 9 years [interquartile range, 7-11 years]; 63 boys) in the validation group. Ultrasonic bone ages in the validation group were evaluated with use of the lists of normal score-for-age values. With radiographic bone age as a reference standard, US could help diagnose abnormal bone age with high sensitivity (93% [14 of 15 participants; 95% CI: 66, 100] for boys, 100% [14 of 14 participants; 95% CI: 73, 100] for girls) and specificity (98% [47 of 48 participants; 95% CI: 88, 100] for boys, 98% [81 of 83 participants; 95% CI: 91, 100] for girls). Conclusion The US scoring system established can be used to evaluate bone age with high sensitivity and specificity. Clinical trial registration no. ChiCTR1900027917 © RSNA, 2021 Online supplemental material is available for this article.

Ultrasonographic assessment of ossification of the distal radial epiphysis for estimating forensic age

Since forensic age estimation is not a valid medical indication, research on the use of nonionizing methods is increasing. Ultrasonography is a radiological approach that protects patients from radiation exposure and offers special convenience to them. In this study, ultrasonography was used for age estimation by investigating the degree of ossification of the distal radial epiphysis. Its applicability on the Turkish population was investigated. The left wrist of 688 (322 males, 366 females) patients between the ages of 9 and 25 years was prospectively evaluated by ultrasonography. The intra- and interobserver reliabilities in evaluating the distal radial epiphysis and Cohen’s kappa statistics show that the interobserver error was very low, and the kappa value was found to be 0.919. Stage 3 and 4 ossification of the distal radial epiphysis was first detected at age 14.3 and 15.3 years in males and 12.7 and 14.8 years in females, respectively. The data obtained may help determine legally critical age limits of 14 and 15. Although it does not seem useful for the age of 18, ultrasonography may be recommended in selected cases as a fast, inexpensive, frequently reproducible radiological method without concern about radiation and without a predictable health risk.

Ultrasonographic evaluation of the wrist and elbow joints: A pilot study to explore a non-invasive technique for age estimation

Age estimation is a vital aspect of the process of identification. Studying the appearance and fusion of long bones is one of the most commonly used methods for age estimation. Most research conducted on age estimation using the study of the appearance and fusion of ossification centres has been roentgenographic in nature. However, X-ray examination and computed tomography examination are associated with ionisation radiation. The present study investigated the use of ultrasonography (USG) as a means of visualising ossification centres of the elbow and wrist joints for age estimation in 31 Maharashtrian boys from Ahmednagar, India. The Schmeling et al. method of grading was used to score the fusion of ossification centres, and simple and multiple linear regression models were developed for age estimation. It was found that the ossification centres of the elbow and wrist joints followed a set pattern of maturation and fusion. The ossification centres of the elbow joint fused before the ossification centres of the wrist joint. The fusion scores of proximal radial epiphyses had the highest correlation with the decimal age of the participants, making its fusion the best indicator among all the ossification centres examined in this study for age estimation. Regression models to estimate age were generated using all the ossification centres. USG was found to be suitable for the purpose of age estimation based on ease of examination, minimal ionisation risks, its non-invasive nature and clear visualisation of ossification centres.

Forensic age assessment of the knee: proposal of a new classification system using two-dimensional ultrasound volumes and comparison to MRI

Objectives

To assess epiphyseal growth plate closure of the knee for forensic age estimation using an ultrasound (US)-based method and to compare the findings with MRI.

Methods

Thirty-three healthy male individuals (age, 14.4–19.3 years) were prospectively evaluated for epiphyseal growth plate closure of the right knee by recordings of two-dimensional US volumes and a high-resolution T1-weighted MRI sequence. The degree of epiphyseal growth plate closure was rated independently by two readers for each method using a modality specific three-point scale that differentiates between an open physis (S1), a partially closed physis (S2), and a closed physis (S3).

Results

The inter-rater agreement was high for the US (Cohen’s kappa (CK): femur 95.2%, tibia 81.3%, fibula 86.3%) and the MRI method (CK: femur 70.2%, tibia 90.8%, fibula 79.8%). The degree of growth plate closure associated positively with advancing age. The US system showed a clearer separation of median ages with lower overlap than the MRI system. Open growth plates on minors (< S3 on femur and tibia) were identified by US with higher sensitivity (1.0 vs. 0.7) and slightly lower specificity (0.7 vs. 0.85) compared with MRI. The examination time was substantially shorter on US than on MRI (2.65 ± 0.91 min vs. 24.72 ± 2.72 min; p < 0.001).

Conclusions

The US method for evaluation of growth plate closure of the knee can reliably assign male individuals to different ossification stages and identifies minors with high accuracy. More studies with larger numbers are needed to further evaluate this method.

Key Points

• US is feasible to determine the degree of epiphyseal growth plate closure of the knee, shows a high degree of reliability, and is comparable to MRI.

• US of the knee can detect open growth plates on male minors with high accuracy.

• US of the knee may be used as a fast, non-invasive imaging tool for forensic age estimation to identify male minors.

Electronic supplementary material

The online version of this article (10.1007/s00330-020-07343-1) contains supplementary material, which is available to authorized users.

Evaluation of craniofacial morphology in short-statured children: growth hormone deficiency versus idiopathic short stature

BACKGROUND

Short stature is defined as a height below the 3rd percentile or more than two standard deviations below the mean for a given age, sex, and population. There have been inconsistent results regarding craniofacial morphology in short-statured children. This study aimed to analyze the differences between short-statured children with growth hormone deficiency, idiopathic short-statured children, and normal children.

METHODS

Thirty-one short-statured children with growth hormone deficiency, 32 idiopathic short-statured children, and 32 healthy children were enrolled in this study. The measurements of their craniofacial structures from lateral cephalograms were evaluated.

RESULTS

There were statistically significant differences among the three groups seven variables (anterior cranial base length, posterior cranial base length, total cranial base length, upper posterior facial height, posterior total facial height, mandibular ramus length, and overall mandibular length) in the linear measurement and five variables (saddle angle, gonial angle, mandibular plane angle, position of mandible, and maxilla versus mandible) in the angular measurement.

CONCLUSION

Compared to the control group, many linear and angular measurements of the craniofacial structures were significantly different in the two short-statured groups (p<0.05). Treatment plans by orthodontists should include these craniofacial structure characteristics.

Summation of Ossification Ratios of Radius, Ulna and Femur: A New Parameter to Evaluate Bone Age by Ultrasound

Radiographic bone age (BA) assessment is reviewer dependent or time consuming. We aimed to clarify the correlation between sonographic ossification ratios (ORs, the ratio of ossification center and epiphysis diameters) of bones and radiographic BA and then to develop a repeatable parameter for BA assessment by ultrasound. The distal ends of the radius and ulna, medial epicondyle of the femur, medial tibial condyle, medial malleolus and lateral malleolus in 271 consecutive patients (132 boys and 139 girls) aged 0.1-19.0 y were imaged by ultrasound. The ORs of these bones were measured sonographically. The highest Pearson correlation r was that between the sum of the ORs of radius, ulna and femur (RUF) calculated from ultrasound images and the radiographic BA (0.97 in boys and 0.96 in girls). The entire process of collecting data and calculating the ORs of RUF took 2.6 ± 0.6 min. The ORs of RUF obtained with ultrasound have potential as an easy-to-perform and efficient quantitative assessment of BA.

US Evaluation of Bone Age in Rural Ecuadorian Children: Association with Anthropometry and Nutrition

Background Stunted growth and development is a serious global public health problem. A limited number of field measures exist that can be used to evaluate stunting and its underlying biologic mechanisms. Purpose To assess bone age using tablet-based US in young children living in a rural community in Ecuador, where stunting is prevalent, and to evaluate the associations between bone age, anthropometry, and diet. Materials and Methods From June through August 2017, tablet-based US was used to assess bone age in young children within their homes in rural Cotopaxi, Ecuador. Bone age z scores (BAZs) were assigned using the standards of Greulich and Pyle. Anthropometric data were collected using international protocols; z scores were generated from World Health Organization Child Growth Standards. Groups were compared using the Student t test. Univariate analyses and generalized linear regression modeling were applied to test the association between bone age and anthropometry, adjusting for covariates including age, sex, dietary intake, and morbidities. Results A total of 128 children (mean age, 33.9 months ± 1.8 [standard deviation]; 59 girls, 69 boys) were evaluated. Mean BAZ was -1.20 ± 1.16. Mean BAZ was lower in children with stunted growth (-1.42 ± 1.18) than in children without stunted growth (-0.98 ± 1.10, P = .04). In adjusted analysis, BAZ was associated with the following variables: height-for-age z score (β coefficient, 0.26; 95% confidence interval [CI]: 0.05, 0.46; P = .01), female sex (β coefficient, 0.51; 95% CI: 0.15, 0.88; P = .006), number of times eggs were consumed in the previous 24 hours (β coefficient, 0.22; 95% CI: 0.05, 0.38; P = .009), number of times savory or salty snacks were consumed in the previous 24 hours (β coefficient, 0.42; 95% CI: 0.15, 0.68; P = .002), and ownership of pig livestock, which was a binary variable (β coefficient, -0.46; 95% CI: -0.82, -0.09; P = .01). Conclusion Bone age determined using tablet-based US was lower in children who had stunted growth and was associated with diet in a cohort of children living in rural Ecuador. © RSNA, 2020 See also the editorial by Dillman and Ayyala in this issue.

Potential Value of Conventional Ultrasound in Estimation of Bone Age in Patients from Birth to Near Adulthood

We aimed to assess the relationship between standard bone age (BA) stratification obtained using plain radiography and that obtained using ultrasound determination of ossification ratio (OR) as a novelty in patients from birth to near adulthood. The ratio of diameters of the ossification center and epiphysis was calculated to evaluate the OR of bones. The ORs of the bones assigned to different weight coefficient were then summed as the skeletal maturity score (SMS). Pearson's correlation r between SMSs derived from ORs and BAs was 0.97 in girls (p < 0.001) and 0.97 in boys (p < 0.001), respectively. There are significant positive correlations between SMSs measured by conventional ultrasound imaging and BAs obtained by radiography of the hand and wrist in patients from birth to near adulthood. The scoring system may potentially provide a quantitative modality to estimate BA by conventional ultrasound.

Bone Age Practices in Infants and Older Children among Practicing Radiologists in Pakistan: Developing World Perspective

Objective To investigate which bone age assessment techniques are utilized by radiologists in Pakistan to determine skeletal age in three defined age groups: less than one year, one to three years and three to 18 years. We also assessed the perceived confidence in skeletal age assessments made by respondents using their chosen bone age assessment technique, within each defined age group. Materials and methods A cross-sectional survey was conducted among 147 practicing radiologists in Pakistan. A pre-validated survey form was adopted from a similar study conducted amongst members of the Society for Pediatric Radiology. The survey collected demographic information, choice of bone age assessment technique in each age group and confidence of bone age assessments in each age group. Results The hand-wrist method of Greulich and Pyle was used by 87.5% of respondents when assessing bone age in infants (less than one year), followed by Gilsanz-Ratib hand bone age method (7.3%). In children aged one to three years, Greulich and Pyle method was chosen by 85.7% of respondents, followed by Gilsanz-Ratib hand bone age method (6.1%) and the Hoerr, Pyle, Francis' Radiographic Atlas of Skeletal Development of the Foot and Ankle (3.1%). In children, older than three years, the Greulich and Pyle technique was used by 83.7% of respondents. This was followed by Gilsanz-Ratib hand bone age method (5.8%) and the Hoerr, Pyle, Francis' Radiographic Atlas of Skeletal Development of the Foot and Ankle (3.8%). 26.4% were "very confident" in bone age assessments conducted among infants. In children aged one to three years, 38.1% were "very confident". In children, greater than three years, 48.6% were "very confident" in their chosen technique. Conclusion Greulich and Pyle is the dominant method for bone age assessments in all age groups, however, confidence in its application among infants and young children is low. It is recommended that clear recommendations be developed for bone age assessments in this age group alongside incorporation of indigenous standards of bone age assessments based on a representative sample of healthy native children.

Ultrasonography in determining pubertal growth and bone age

OBJECTIVE:

The purpose of this study is to evaluate the compatibility of ultrasonographic data with hand-wrist radiographs taken to determine the extent of pubertal growth and bone age in patients and investigate the usability of ionizing radiation-free ultrasonography instead of conventional radiography.

METHODS:

In this study, a total of 120 children from 10 to 17 years old (mean age was 168 months ± 27.5 months) were treated with routine radiographs before orthodontic treatment, and ultrasonographic imaging was performed on the wrists the same day. Researchers examined the phalanges, sesamoid bone, and radial bone distal epiphysis-diaphysis comparatively in each patient by both imaging methods and statistical evaluation.

RESULTS:

There was no statistically significant difference between conventional radiography and ultrasonography values at 13 points except for PP1 (proximal phalanges of the first finger), PP2 (proximal phalanges of the second finger), and radial epiphysis (p > 0.05). PP1, PP2, and radial epiphysis showed a statistically significant difference (p < 0.05). The CBA (bone age obtained from conventional radiographs) of the females was found to be larger than their CA (chronological age) and their UBA (ultrasonographic bone age). For males; the means of the CBA, UBA and CA values close to each other. In females and males; there was a strong correlation between the CA, the UBA and the CBA (p < 0.01).

CONCLUSION:

Ultrasonography gives detailed information about epiphyseal diaphysis relations. It can be used as an alternative to conventional radiography in the detection of bone age and pubertal growth, owing to the absence of ionizing radiation.

Assessment of adulthood in the living Spanish population based on ossification of the medial clavicle epiphysis using ultrasound methods

It is a fact that in recent years requests have greatly increased to obtain estimates of the legal age of undocumented individuals alleged to be minors who have been forced to enter different European Community countries for socioeconomic reasons or due to war. Spain is one of the countries most affected by this illegal immigration because of its proximity to North Africa. Therefore, it has become necessary to develop new standards which help provide a response to the demands of the justice administration. In recent years, the Superior Justice Court has rejected several pieces of expert evidence on the grounds that the age intervals therein were not sufficiently reliable and that the radiographic techniques used to determine age were invasive, potentially causing harm to the alleged minor. These sentences have caused interest in this field of work to increase within the scientific community. As a result, in order to improve age predictions and, above all, reduce minors' exposure to radiation, this study was created for completion on the Spanish population, using the ultrasound scan as a diagnostic technique. Used as a study sample were the ultrasound images of the proximal sternal epiphysis of the clavicle among 221 individuals of both sexes, of ages ranging from 5 to 30 years. All of the images were classified into 4 stages of fusion, in accordance with the development of metaphyseal closure proposed by Schulz et al. in 2008. The results show differences among the 4 proposed groups for each of the stages of fusion, with the results found in Stage II being especially important because, for both sexes, they would imply that the patient studied has reached an age of over 18 years, which is the legal age of adulthood in Spain, as established by the Spanish Constitution of 1978. Though further research is still recommended, these results, coupled with the use of ultrasound as a non-invasive diagnostic technique, could help solve some of the problems currently arising in justice courts.

A simple method for bone age assessment: the capitohamate planimetry

Objectives

To determine if the capitohamate (CH) planimetry could be a reliable indicator of bone age, and to compare it with Greulich-Pyle (GP) method.

Methods

This retrospective study included 391 children (age, 1–180 months). Two reviewers manually measured the areas of the capitate and hamate on plain radiographs. CH planimetry was defined as the measurement of the sum of areas of the capitate and hamate. Two reviewers independently applied the CH planimetry and GP methods in 109 children whose heights were at the 50th percentile of the growth chart.

Results

There was a strong positive correlation between chronological age and CH planimetry measurement (right, r = 0.9702; left, r = 0.9709). There was no significant difference in accuracy between CH planimetry (84.39–84.46 %) and the GP method (85.15–87.66 %) (p ≥ 0.0867). The interobserver reproducibility of CH planimetry (precision, 4.42 %; 95 % limits of agreement [LOA], −10.5 to 13.4 months) was greater than that of the GP method (precision, 8.45 %; LOA, −29.5 to 21.1 months).

Conclusions

CH planimetry may be a reliable method for bone age assessment.

Key Points

• Bone age assessment is important in the work-up of paediatric endocrine disorders.

• Radiography of the left hand is widely used to estimate bone age.

• Capitatohamate planimetry is a reliable and reproducible method for assessing bone age.

The completely fused medial clavicular epiphysis in high-frequency ultrasound scans as a diagnostic criterion for forensic age estimations in the living

The assessment of ossification of the medial clavicular epiphysis plays a decisive role in the forensic age estimation of living subjects. Primarily for reasons of minimizing the radiation exposure currently associated with such evaluations, non-ionizing methods would be an advance.This study pursued the question whether full union of the medial clavicular epiphysis, visualized by high-frequency sonography, is a reliable criterion for age-threshold determinations. The ossification stage of the medial clavicular epiphysis of 215 female and 195 male volunteers, aged between 14 and 26 years, was evaluated in bilateral sonograms. Stage 4, defined as complete fusion by Schulz et al. (Int J Legal Med 122:163-167, 2008), was observed on at least one body side in 48 of 334 individuals younger than 21 years (14.4 %) and in 32 of 264 individuals younger than 18 years (12.1 %).With the high-frequency ultrasound used in this study, even the smallest convexities of the medial clavicular ending can be visualized. This may have led to overestimation of the ossification stage. It is not clear whether any observed roundings in the sonograms should actually be interpreted in terms of stages 3 and 4 as defined by Schulz. Also, due to the low penetration depth of high-frequency ultrasound waves, epiphyseal plate residues and ossification centers may have remained undetected. Reliable differentiation of the stages 1-4 with high-frequency sonography is thus difficult, and the results suggest that this method is not a radiation-free alternative to computed tomography, the current gold standard for determining age thresholds.

The utility of ultrasonographic bone age determination in detecting growth disturbances; a comparative study with the conventional radiographic technique

OBJECTIVE

To test whether the conventional radiographic technique in determining bone age abnormalities can be replaced by ultrasonography.

MATERIALS AND METHODS

A total of 54 Caucasian subjects up to 7 years of age with clinically suspected growth problems underwent left hand and wrist radiographic and ultrasonographic bone age estimations with the use of the Greulich-Pyle atlas. The ultrasonographic scans targeted the ossification centers in the radius and ulna distal epiphysis, carpal bones, epiphyses of the first and third metacarpals, and epiphysis of the middle phalanx, as described in previous reports. The degree of agreement between the two sets of data, as well as the accuracy of the ultrasonographic method in detecting radiographically suggested bone age abnormities, was examined.

RESULTS

The mean chronological age, radiographic bone age, and ultrasonographic bone age (all in months) were 41.96 ± 22.25, 26.68 ± 14.08, and 26.71 ± 13.50 in 28 boys and 43.62 ± 24.63, 30.12 ± 17.69, and 31.27 ± 18.06 in 26 girls, respectively. According to the Bland-Altman plot there was high agreement between the results of the two methods with only three outliers. The deviations in bone age from the chronological age taken by the two techniques had the same sign in all patients. Supposing radiography to be the method of reference, the sensitivity, specificity, positive predictive value, and negative predictive value of sonography in detecting growth abnormalities were all 100% in males and 90.9, 100, 100, and 93.8%, respectively, in females.

CONCLUSION

The conventional radiographic technique for determining bone age abnormalities could be replaced by ultrasonography.

Bone age assessment with conventional ultrasonography in healthy infants from 1 to 24 months of age

BACKGROUND

Radiographic bone age determination is part of the routine evaluation of suspected growth disorders. Simplicity and low cost are its major advantages, but although the effective dose of ionizing radiation is low, it should be taken into consideration given its cumulative effect.

OBJECTIVES

To assess the chronological ultrasonographic emergence of the ossification centers of the hand and wrist.

MATERIALS AND METHODS

Cross-sectional study of healthy patients ages 1 to 24 months (n=498) from Buenos Aires, Argentina. All patients underwent ultrasonographic evaluation of the left hand and wrist to identify the different bone nuclei; a subgroup of infants had their nuclei measured (n=228).

RESULTS

Girls showed an earlier emergence of the evaluated nuclei and a trend to a greater size than age-matched boys. Size-for-age relation showed linear increase. Carpal bones (capitate and hamate) were the first to appear, as early as from the first 3 months of life, an age gap not thoroughly present on the radiographic atlas developed by Greulich and Pyle. The distal epiphysis of the radius and the second metacarpophalangeal joint (index finger) followed in order of emergence. The proximal epiphysis of the first metacarpal bone (thumb) was the last to emerge and was infrequently found on boys at age 24 months. Overall, these findings are in accordance with the radiographic atlas. An ultrasonography atlas of the left hand and wrist was outlined for girls and boys.

CONCLUSION

Conventional ultrasonography allows proper identification of the ossification centers of the hand and wrist and may become an innocuous follow-up tool for patients with growth disorders.

Virtual anthropology: useful radiological tools for age assessment in clinical forensic medicine and thanatology

Virtual anthropology consists of the introduction of modern slice imaging to biological and forensic anthropology. Thanks to this non-invasive scientific revolution, some classifications and staging systems, first based on dry bone analysis, can be applied to cadavers with no need for specific preparation, as well as to living persons. Estimation of bone and dental age is one of the possibilities offered by radiology. Biological age can be estimated in clinical forensic medicine as well as in living persons. Virtual anthropology may also help the forensic pathologist to estimate a deceased person's age at death, which together with sex, geographical origin and stature, is one of the important features determining a biological profile used in reconstructive identification. For this forensic purpose, the radiological tools used are multislice computed tomography and, more recently, X-ray free imaging techniques such as magnetic resonance imaging and ultrasound investigations. We present and discuss the value of these investigations for age estimation in anthropology.

Age determination using ultrasonography in young football players

Background:

Increasing of age cheating in sports makes problems to athletes comparable to taking illegal substances. Current method used by AFC and FIFA is applying MRI of growth plate of distal of radius to determine the bone age. This study was designed to evaluate the diagnostic accuracy of ultrasonography in bone age determination by measuring the width of growth plate in distal of radius, and comparing it with identity documents.

Materials and Methods:

The study was conducted from September to December 2009 in the Department of Radiology at Al-Zahra University Hospital, Isfahan, Iran. Ultrasonography was done for 82 (15-20 years old) young professional football players and results were compared with identity documents (such as National ID card). Young football players were divided into three age categories: < 16 and > 16 years old, < 17 and > 17 years old, and < 18 and > 18 years old. Receiver Operator Characteristics (ROC) curves for discriminant values and sensitivity and specificity were analyzed.

Results:

Cut-off point was set for each group, based on the width of the growth plate, and negative test was defined as subjects < cut-off point, showing subjects over the defined age in each group. ROC curve analysis demonstrates consistently acceptable diagnostic sensitivity and specificity values in age determination of each group.

Conclusions:

The overall predictive accuracy of ultrasonography, as described by the area under the ROC curve, was high for determination of bone age. It has an acceptable sensitivity and specificity to use for determination of age in sport competitions, and has the capability to become the screening test for age determination, especially because it is inexpensive and without any risk of radiation. It seems to be comparable with MRI in age determination.

The use of magnetic resonance imaging to examine ossification of the proximal tibial epiphysis for forensic age estimation in living individuals

The establishment of radiation-free examination procedures in the field of forensic age diagnostics in living persons is to be considered of special scientific interest so as to minimize necessary exposure to X-rays while facilitating additional assessment of skeletal development in all cases. To this end, the advantages offered by magnetic resonance imaging in securing a practical application which is as unrestricted and complication-free as possible should be among the methods exploited in investigating such indicators of skeletal maturity. Within the framework of a retrospective study, we investigated the ossification status of the proximal tibial epiphysis on the MRI scans of 124 females and 166 males aged between 10 and 30 years. All the images had been generated on a 3.0 T scanner using a T1-weighted turbo spin-echo sequence. When evaluating the ossification stage, a combination of modified classifications proposed by Schmeling et al. and by Kellinghaus et al. was used. The statistical evaluation included calculation of a variety of measures to describe specific ossification stages as well as kappa coefficients to assess intra- and inter-observer agreement on diagnoses of individual stages. In forensic contexts, completion of the 14th year of life can be adequately evidenced in females with an ossification stage IV according to Schmeling et al. and in males with an ossification stage III c according to Kellinghaus et al. or an ossification stage IV according to Schmeling et al. In forensic contexts, the presence of an ossification stage IV according to Schmeling et al. can prove that the age of 16 years has been exceeded only in the male sex, whereby for age estimation purposes the diagnosis should be in line with other skeletal maturity indicators. The results available displayed a high degree of intra- and inter-observer agreement. Examination of the ossification status of the proximal tibial epiphysis using magnetic resonance imaging represents an effective additional tool for use in radiation-free forensic age diagnostics in living persons.

Skeletal age assessment in children using an open compact MRI system

MRI may be a noninvasive and alternative tool for skeletal age assessment in children, although few studies have reported on this topic. In this article, skeletal age was assessed over a wide range of ages using an open, compact MRI optimized for the imaging of a child's hand and wrist, and its validity was evaluated. MR images and their three-dimensional segmentation visualized detailed skeletal features of each bone in the hand and wrist. Skeletal age was then independently scored from the MR images by two raters, according to the Tanner-Whitehouse Japan system. The skeletal age assessed by MR rating demonstrated a strong positive correlation with chronological age. The intrarater and inter-rater reproducibilities were significantly high. These results demonstrate the validity and reliability of skeletal age assessment using MRI.

Estimation of age in the living: in matters civil and criminal

Estimation of age is one of the main tasks of a forensic practitioner, especially in third world countries, where many births take place in rural settings without the benefit of the expert supervision of a trained obstetrician. Such births are poorly recorded or more often not recorded at all in terms of exact dates. In many other cases, records are fraudulently falsified for some gain, e.g. to get government jobs or pensions. Developed countries, where ordinarily the birth records are meticulously maintained, are not immune to this problem either. Estimation of the age of living individuals may be needed here for refugees or other persons who arrive without acceptable identification papers. A wide variety of methods are used by the forensic clinician to assess the age of the individual in such cases. This paper discusses and evaluates the most common methods used in India, although the methods can be effectively utilized by medico-legal professionals anywhere in the world.

Application of ultrasound for bone age estimation in clinical practice

OBJECTIVE

To assess the validity of bone age assessment by ultrasonography (US).

STUDY DESIGN

Wrist US was performed on children (n = 100) undergoing radiographic bone age and compared with bone age estimation by a radiologist in the clinic and by endocrinologists under blinded conditions with Greulich and Pyle (GP) and Tanner and Whitehouse (TW3) methods.

RESULTS

The strongest correlation (r(2)) was seen in the radiographic bone age assessment between the 2 endocrinologists using the GP method (96.7%). The poorest correlation was seen when comparing radiographic methods to US of either wrist (74.6% to 82.6%). When bone age correlations were divided into normal, delayed or advanced, the highest correlation between the radiographic and US methods was found in the normal bone age group (80.9% to 86.1%) with weaker correlations for the delayed bone age group (77.1% to 86.9%) and the advanced bone age group (62.2% to 81.1%). US tended to overread delayed bone age and underread advanced bone age. US had poor positive and negative predictive value for identification of a normal or delayed bone age. The negative predictive value of US was 91% for an advanced bone age.

CONCLUSIONS

On the basis of our data, US assessment should not yet be considered a valid replacement for radiographic bone age determination.

Radiographic versus ultrasound evaluation of the Risser Grade in adolescent idiopathic scoliosis: a prospective study of 46 patients

The determination of skeletal age is essential in the management of patients with scoliosis. One of the most frequently used techniques to determine skeletal maturity is the method described by Risser. However, repeated X-ray exposure in the follow-up examinations of scoliosis patients may increase the risk of cancer. We compared conventional radiological evaluation of the Risser grade with ultrasound evaluation. For scoliosis patients routine application of ultrasound in the follow-up examinations may significantly reduce radiation exposure. 46 adolescent idiopathic scoliosis patients (median age, 14.5 years) were investigated. Sonographic and radiographic assessment of Risser sign was carried out by two independent senior staff skeletal radiologists. Agreement of Risser Grade between the two diagnostic methods was determined by Kappa statistics. Coefficients <0.21, 0.21-0.40, 0.41-0.60, 0.61-0.80, and >0.80 were rated as poor, fair, moderate, good, and very good agreement. For Risser Grades I-III 100% agreement was found between the two methods. Disagreement between radiographic and sonographic evaluation was found in Risser Grades IV and V. In five patients, X-ray evaluation yielded Risser Grade V while ultrasound showed Risser Grade IV. In one patient, radiographic examination resulted in Risser Grade IV while Grade V was detected in ultrasound. Overall, the Kappa value showed very good agreement between the two diagnostic methods. Our findings suggest that ultrasound can be applied as an alternative method to X-ray evaluation in Risser Grade determination. It should be routinely used in clinical practice to reduce the patients exposure to radiation.

Ultrasound studies on the time course of clavicular ossification

When preparing forensic age estimates for living subjects over 18 years of age, it is crucial to evaluate the stage of ossification of the medial clavicular epiphysis. The establishment of radiation-free imaging techniques for assessment of clavicular ossification would be desirable in order to reduce the radiation exposure associated with forensic age estimations. In the present study, 84 right clavicles of test subjects 12-30 years of age were prospectively evaluated by means of ultrasound. Ossification stage classification was possible in 80 of the 84 medial clavicular epiphyses studied. In the remaining cases, stage classification was not possible due to the presence of developmental anomalies. The earliest ages at which the respective ossification stages were observed were 17.1 years for stage 2, 16.7 years for stage 3, and 22.5 years for stage 4. The age intervals observed for the ossification stages are consistent with the known data from radiological and computed tomography assessments. The present study results should be confirmed in a larger number of cases and with analysis of observer variability. Evaluation of medial clavicular epiphyseal ossification by ultrasound could ultimately be a rapid and economic non-ionizing diagnostic imaging procedure for forensic age estimation.

Age estimation

While age estimation of unidentified corpses and skeletons for identification purposes has a long tradition in forensic sciences, age estimation of living persons has formed a relatively recent area of forensic research which is becoming increasingly important. The international interdisciplinary Study Group on Forensic Age Diagnostics (AGFAD) issued recommendations for age estimation of living persons for the purpose of criminal, civil, asylum and old-age pension procedures as well as for determining the sex and age of skeletons. In the present work, the authors set out state-of-the art age estimation methods for specific case groups, define minimum requirements for reference studies and specify the need for further research. In addition, ethical and medico-legal aspects as well as issues relating to quality assurance are discussed.

Age determination by magnetic resonance imaging of the wrist in adolescent male football players

BACKGROUND

In football there are established age-related tournaments for males and females to guarantee equal chances within the game for all the different age groups. To prevent participation in the incorrect age group, and owing to the fact that in some Asian and African countries registration at birth is not compulsory, other methods of age determination need to be available. Standard radiographs of the left wrist have been used for assessment of skeletal age for many years. This is, however, not ethical in the sporting environment.

AIM

To study the possible use of magnetic resonance imaging (MRI), which has no radiation risk, in estimating the age of healthy adolescent football players.

METHODS

The examination protocol was applied in four countries using, their respective MRI equipment using a 1-T or 1.5-T magnet and a wrist coil. 496 healthy male adolescent football players between the ages of 14 and 19 years from Switzerland, Malaysia, Algeria and Argentina were selected for the study. The degree of fusion of the left distal radial physis was determined by three independent raters by a newly developed grading system which can be used in future MRI epiphysial fusion grading studies.

RESULTS

The inter-rater reliability for grading was high (r = 0.91 and 0.92); all correlations were highly significant (p<0.001). The average age increased with a higher grading of fusion, and the correlation between age and grade of fusion was highly significant (r = 0.69, p<0.001). Only one player (0.8%) in the 16-year-old age group was graded as completely fused.

CONCLUSION

MRI of the wrist offers an alternative as a non-invasive method of age determination in 14-19-year-old male adolescents. The grading system presented here clearly identifies the skeletal maturity by complete fusion in all MRI slices, which eliminates any risk associated with standard radiographic rating as determined by the International Atomic Energy Agency.

Assessment of skeletal age at the wrist in children with a new ultrasound device

BACKGROUND

Determination of skeletal development in children is important. The most common method of evaluation uses the standards of Greulich and Pyle (G and P) to assess the left hand radiograph. Numerous assessments may be made during follow-up.

OBJECTIVE

The aim of our study was to compare the accuracy of a new sonographic method with the standard radiographic method.

MATERIALS AND METHODS

Seventy consecutive patients (age 6-17 years; 34 girls, 36 boys) underwent radiography of the left hand, followed by sonographic examination of the same hand using the BonAge system (Sunlight Medical Ltd., Israel). This system evaluates the relationship between the velocity of sound passing thorough the distal radial and ulna epiphysis and growth, using gender- and ethnicity-based algorithms. One experienced paediatric radiologist analysed the radiograph and assigned bone age scores based on the G and P atlas for the whole left hand and for the distal radius alone. The radiologist was blinded to the chronological age (CA), height of the patient and the BonAge result. Correlation between BonAge and G and P was undertaken.

RESULTS

In 65 patients, BonAge measurement could be performed successfully. In five patients, the scanning process was impossible using the ultrasound device. The r(2) (r is the Pearson correlation coefficient) of the BonAge ultrasound measurement and the G and P method was 0.82. The averaged accuracy (i.e. absolute difference in years between G and P reading and BonAge ultrasonic results) was calculated. Results were similar for boys and girls: 1.0+/-0.8 years for the whole left hand and 0.8+/-0.7 year for the distal radius. On average, the difference between BonAge and CA is the same as the difference between G and P and CA, i.e. 1.4 years.

CONCLUSIONS

The BonAge device demonstrates the ability of ultrasound to produce an accurate assessment of bone age. The results are highly correlated with skeletal age evaluated conventionally using the G and P method. Obvious advantages of the ultrasound device are objectivity, lack of ionizing radiation, and easy accessibility.