Introduction: Extended vertex craniectomy in sagittal synostosis (SS) and transposition craniectomy in severe deformational brachycephaly (DB) combined with mosaic-like cranioplasty (M-LC) have been performed in 17 and 24 infants from 2001 to 2003. The hitherto not well-known mechanisms of remodeling and effectiveness of M-LC is assessed by X-ray and anthropometry.
Methods: Follow-ups included skull radiograms preoperatively and 3 and 15 months postoperatively, which were analyzed by craniometry according to Haas, long-term anthropometry, and clinical follow-up till mean age of 7.6 and 7.4 years. Analysis included the following: time course of cephalic indexes (CI), sizes of distances (breadth, length, height) and modulus, and mean deviation of distances and modulus from the normal age- and sex-dependent values; evaluation of re-ossification of the operative defects covered by M-L C.
Results: CI in SS is normalized in early follow-up with stabilization thereafter; CI of DB is gradually normalized till late follow-up. Remodeling occurs in both disorders by active and passive mechanisms: increased growth of distances with preoperative minus and decreased growth of distances with surplus. The latter mechanism adds more to the postoperative remodeling. M-LC leads to concentric and final complete re-ossification of the defects.
Discussion: Significant remodeling of the skull vault is observed in both disorders by the demonstrated time course and mechanisms. M-LC does not hinder early remodeling and guarantees re-ossification of the defects.
Keywords: Long-term skull transformation; Scaphocephy/postural brachycephaly; Surgery; X-ray craniometry/anthropometry.