Anthropometric Outcomes following Fronto-Orbital Advancement for Metopic Synostosis.

BACKGROUND

The authors' purpose is to present changes in anthropometric fronto-orbital dimensions after surgical correction of metopic synostosis.

METHODS

The authors retrospectively analyzed craniometric dimensions in older patients with metopic synostosis corrected by fronto-orbital advancement performed by the senior author (J.B.M.). Preoperative and postoperative linear measures (frontal breadth, cranial width, and intercanthal distance) were taken by direct anthropometry. Interdacryon distance and width of the bandeau were also recorded intraoperatively, before and after widening. Follow-up anthropometric values were compared to age- and sex-matched normative data and standard (z) scores were calculated.

RESULTS

Sixteen patients met the inclusion criteria. Syndromic diagnosis was documented in five of 16 patients. Average age at the last postoperative evaluation was 8.9 ± 3.8 years (range, 4 to 16 years). Mean frontal width z-scores decreased postoperatively from 0.82 to -0.32 (p = 0.007), indicating diminished growth in this dimension. The last measured frontal width strongly correlated with the breadth of the bandeau after surgical correction but not with preoperative values. Postoperative mean cranial width diminished significantly to a more normal value. Mean intercanthal distance was normal preoperatively and remained so but was significantly greater in syndromic than in nonsyndromic cases.

CONCLUSIONS

Frontal growth rate is diminished in the coronal plane after fronto-orbital advancement. The authors recommend primary techniques to overcorrect the width of the bandeau and frontal region, including zygomaticosphenoid osteotomies and interpositional cranial bone grafts to advance/widen the lateral orbital rim. Continued evaluation is required to assess whether overcorrection results in normal frontotemporal shape and breadth at skeletal maturity.