Quantification of the timing of anterior fontanelle closure in a Western Australian population

Abstract

Closure of the anterior fontanelle is generally accepted to occur within the first two years of life. However, statistical quantification of the precise timing of closure in a Western Australian population has not been explored. The current study examined MDCT scans of 68 individuals between birth and 3.91 years to assess the timing of anterior fontanelle closure. Using OsiriX, the scans are viewed in axial and multiplanar reconstructed (MPR) images and three-dimensional volume rendered reconstructions. Anterior fontanelle fusion status was quantified using two methods: calculating anterior fontanelle area and by taking the oblique linear distances of the open fontanelle. The single greatest proportion of fusion was shown to occur in the first year of life, by which stage only 47.19% of the fontanelle remains unfused (on average by area). There was only one individual demonstrating complete fusion before 1 year of age (0.86 years) with no single individual presenting an open fontanelle beyond 2.4 years of age. The current study outlines statistically quantitated data that facilitates forensic age estimation (either macroscopic or radiographic) specific to Australian individuals from the perinate to early childhood life stages.

Closure of the anterior and posterior fontanelle in the New Zealand population: A computed tomography study

“…The only other CT‐based fontanelle study was Australian and analysed its data in 6‐monthly groups. The mean size of the Māori/Pasifika AF in 0–6 months was 580 mm 2 , smaller than the average of 693 mm 2 in the Australian study …”

“…The mean size of the M aori/Pasifika AF in 0-6 months was 580 mm 2 , smaller than the average of 693 mm 2 in the Australian study. 10 To date, Perera et al have conducted the largest study of clinically assessed AF size in the neonate (n = 2215); this crosssectional study demonstrated the extent of the normal variation present in the Sri Lankan population, with 97% of neonates having a SA between 90 and 450 mm 2 . 20 Published literature has demonstrated significant ethnic variation in fontanelle size, with averages ranging from 225 mm 2 (AE79 mm 2 ) in the Hispanic population to 340 mm 2 (AE60 mm 2 ) in Nigeria.…”

“…Almost a quarter of the population in New Zealand identify as being either Māori or from the Pacific Islands; to date, however, there has been no study looking at the AF size and closure rates in this population. The further removed (geographically, genetically or temporally) an individual is from the sample population on which the standards were based, the less reliable it is for use in that individual . Therefore, the primary goal of this paper was to use cross‐sectional computed tomography (CT)‐acquired data to statistically quantify the age at which the AF closes in the New Zealand population.…”

“…The further removed (geographically, genetically or temporally) an individual is from the sample population on which the standards were based, the less reliable it is for use in that individual. 10 Therefore, the primary goal of this paper was to use cross-sectional computed tomography (CT)-acquired data to statistically quantify the age at which the AF closes in the New Zealand population.…”

A morphometric evaluation of anterior fontanel and cranial sutures in infants using computed tomography

“…This may be due to racial differences, geographic location, and nutritional status (8,9,22). The mean size of AF in the first six months in the Maori/Pasifika group was 580 mm 2 (21) and with an average value of 693 mm 2 was in the Australian study (25). In our study, the median of the AF area was 605 ± 514.30 mm 2 which was higher than the Maori/Pasifika study and lower than the Australian study, which indicates the variation of AF among populations.…”