Abstract:
HTML
Purpose: In prepubertal children, to determine how chronological age varies with total volume of secondary ossification center and of epiphyseal cartilage on distal femoral MRI studies of children.
Methods and Materials: Clinical MR images of the distal femur obtained at two institutions between February 2000 and February 2003 were studied; cases were included if MRI showed no bony or cartilaginous pathology. Sagittal proton density and T2-weighted MR images in 32 children (17 girls, 15 boys) aged 16 months to 11 years and 7 months were selected. Inclusion criteria were a) visualization of the entire distal femoral epiphysis, b) availability of proton density and/or T2-weighted images in the sagittal plane and c) thin MR slices (series of images ranged from 13 - 60 slices). Volume measurements were calculated using Cheshire software, by multiplying area measurements (in mm2) by the sum of slice thickness (3 - 5 mm) and interslice gap. Chronological age was plotted against total secondary ossification center volume and against total epiphyseal cartilage volume to determine if a linear relationship existed.
Results: Variation of epiphyseal volumes with age was analyzed using the Spearman rank correlation, measuring the strength of association (r and P values) between chronological age and total secondary ossification center volume, and between chronological age and total epiphyseal cartilage volume. Ossification center volume increased from 7056 mm3 to 834,902 mm3. Cartilage volume increased from 23,420 mm3 to 463,415 mm3. Correlation was higher between age and secondary ossification center volume ( r= .76, p<.01) than between age and epiphyseal cartilage volume (r=.61, p=.0002). The trend for both ossification center and cartilage revealed volume increase with mean age increase. Wilcoxon rank sum test showed no significant difference in volumes between genders.
Conclusion: There is an age-related increase in distal femoral ossification center and cartilage volumes from one to eleven years of age. The correlation is greater for bone volume than for cartilage volume. Preliminary data suggest that automated epiphyseal volumetric measurement may serve to evaluate skeletal maturity, particularly before puberty.
Questions about this event email: djaramillo@partners.org
Kamath, A,
Femoral Secondary Ossification Center and Femoral Epiphyseal Cartilage: Correlation of Volume and Chronological Age of the Patient. Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL.
http://archive.rsna.org/2003/3100904.html
