Further Applications of EDMA - An Invariant Approach to Statistical Analysis of Shapes - page 266

suture fusion to inhibit proper growth. Two distances show more than
a 10% difference between the fused and unfused sides: FZJ — EAM and
FZJ — AST. This finding is expected because two measurements are
perpendicular to the fused suture (FZJ is anterior to it, while EAM and
AST are posterior), and the greatest limitation of growth should be in
this direction. Most of the other measurements with confidence inter-
vals excluding 1 indicate that the fused side of the cranium is shorter
from front to back, which agrees with the “twisted” appearance of the
cranial base and face when viewed from above ( Figure 7.3 ).
Figure 7.3 Studying asymmetry with EDMA, showing the pattern of asymmetry in
the sample of unicoronal patients. The fused coronal suture is on the left side. Black
lines indicate distances where the fused-side measurements are smaller than the
unfused-side measurements, so that a 90% confidence interval for their ratio excludes
one (see text). The white line indicates the single distance where the fused-side mea-
surement was larger than its unfused-side counterpart. Landmarks: NAS — nasion;
SEL — sella; BAS — basion; OPI — opisthion; FZJ — frontozygomatic junction; EAM
— external auditory meatus; AST — asterion.