The effects of radiation on craniofacial skeletal growth: a quantitative study.

To determine whether radiation delivered to children treated for head and neck cancer causes deformity, we performed a quantitative analysis for craniofacial asymmetry. A total of 42 patients, with either rhabdomyosarcoma or nasopharyngeal carcinoma, treated between 1980 and 1991, were analyzed. Exclusions included 16 subjects, leaving 26 children of mixed race and gender with a median age at diagnosis of 13 years (range: 2-18) and a median age at follow-up of 4 years (range: 3-37). Data from 14 measurements of the cranium and facial skeleton, for which normative data exist, were recorded. Symmetry of the face and head were determined and each measurement was compared to age specific standards. Deviation occurred in the cranial vault, the anterior and mid-interorbital distances and lateral orbital wall length. Asymmetry existed in the medial and lateral orbital wall lengths and the zygomatic arches. We conclude that, children irradiated for head and neck malignancies, have significant alterations in some skeletal measurements indicative of treatment induced asymmetry and potential deformity.