Proatlas anomalies in craniofacial malformations: 5-year experience in King Chulalongkorn Memorial Hospital

Abstract

Purpose: To review the prevalences of proatlas anomalies in craniofacial malformations and evaluate the relation between craniofacial malformation and proalast anomalies.

Methods: The 221 patients with craniofacial malformation who underwent CT facial bone and 3D brain in King Chulalongkorn Memorial Hospital (KCMH). Then, the craniofacial malformed patients are classified into six groups composed of craniosynostosis, cephalocele, midface anomaly, facial and branchial arch syndrome, facial cleft face, and others. Reviewing image finding by the researcher and the radiologist advisor was done separately and gave the consensus in the case with disagreement. Qualitative analysis of the prevalence of proatlas anomalies was achieved. In addition, assessment of the relationship between craniofacial malformation and proatlas anomalies was conducted using Pearson's chi-square test to determine statistical significance.

Result: The proatlas anomalies were presented in 26 patients of 221 craniofacial malformed patients. Details of frequentative proatlas anomalies consist of pre-basioccipital arch in eight patients, os odontoideum in five patients, bony mass along the margin of foramen magnum in three patients, atlas assimilation in two patients, hypertrophic occipital condyle in one patient, third occipital condyle in one patient, and mixed characteristic of proatlas anomalies in six patients. These results represented pre-basioccipital arch and os odontoideum as the two most common presentations among proatlas anomalies and also showed significant existence of proatlas diseases in craniofacial malformation (p value = 0.006).

Conclusion: Our results emphasize the existence of proatlas anomalies which should be carefully looked for, particularly in craniofacial malformed patients due to significant statistical correlation.

Keywords: Craniovertebral malformation; Os odontoideum; Pre-basioccipital arch; Proatlas segmental anomalies.