The effect of neurocranial surgery on basicranial morphology in isolated sagittal craniosynostosis

Objective: Isolated sagittal craniosynostosis produces a scaphocephalic neurocranium associated with abnormal basicranial morphology, providing further evidence of the interrelated growth patterns of the neurocranium and basicranium. Corrective surgical procedures vary, but the immediate impact of the surgical procedure is restricted to the neurocranium. This study addresses the secondary effects of neurocranial surgery on the cranial base. Design: We obtained 3-D CT scans for pre-operative (N = I 9) and post-operative (N = I 0) patients with isolated sagittal synostosis. Landmark data from 14 landmarks on and around the cranial base were collected from 3-D CT reconstructions and analyzed using Euclidean Distance Matrix Analysis (EDMA). Form differences between an age-matched subsamples of pre- and post-operative patients allowed us to make inferences about differential growth trajectories: one in the presence of a fused suture, and one in the presence of a surgically-released suture. Results: We found statistically significant differences (a < 0.05) in the morphology of the cranial base in pre-operative and post-operative patients. The relative positions of landmarks nasion, right asterion, and left asterion are similar in pre-operative and post-operative patients. However, the position of these landmarks in relation to the cranial base is different in the two groups, being located more anteriorly in post-operative patients. In addition, we found an increase in the cranial base angle in the first post-operative year. Conclusion: Neurocranial surgery in sagittal synostosis patients affects growth patterns in the cranial base. The increase in the cranial base angle suggests a post-operative reversal of the decreased cranial base angle and occipital over-rotation.

 Images from the publication.

 

This figure shows the differences in craniofacial form in patients who have undergone surgery vs. patients who have not undergone surgery.

 

This image illustrates the landmarks digitized from a 3D-CT reconstruction of a patient with isolated sagittal synostosis.