The Degree of Surgical Frontal Volume Correction in Metopic Synostosis Determines Long-Term Outcomes:

Anthropometric cranial measurements in metopic craniosynostosis/trigonocephaly: diagnostic criteria, classification of severity and indications for surgery

ABSTRACT

Metopic craniosynostosis is the second most frequent type of craniosynostosis. When the phenotypic presentation has been deemed severe the treatment is surgical in nature and is performed in infancy with fronto-orbital advancement and cranial vault remodeling. At the time of this writing, there is no consensus regarding an objective evaluation system for severity, diagnostic criteria, or indications for surgery. This study aims to review the anthropometric cranial measurements and the relative diagnostic criteria/classification of severity/surgical indications proposed so far for this skull malformation, and to investigate if there is any scientific support for their utility.

Outcomes of Surgical Management of Metopic Synostosis : A Retrospective Study of 18 Cases

Objective

To describe the surgical management and postoperative outcomes in infants with metopic synostosis.

Methods

We conducted a 5 years retrospective chart review of patients who underwent surgical correction of metopic synostosis at two university hospitals in Egypt during the period between June 2014 and June 2019. The study is conducted to 18 children. The type of surgical procedures and postoperative outcomes were assessed in all patients.

Results

Five cases (27.8%) underwent endoscopic-assisted suturectomy, 10 cases (55.6%) underwent craniofacial reconstruction, and three cases (16.6%) underwent open burring of the metopic ridge. Fifteen patients underwent one surgery and three patients (16.6%) who need second operation. Ten patients (55.6%) had class I Whitaker classification.

Conclusion

Regardless of type of surgery, the outcomes of surgical correction of metopic synostosis are excellent with only a few patients require revision or develop major complications.

Long-Term Growth following Trigonocephaly Repairs: Are Overcorrections Necessary?

BACKGROUND

Does bifrontal width change with growth following trigonocephaly corrections? Postoperative long-term growth was assessed, along with the impacts of phenotypic severity, surgical timing, and operative technique, to determine how wide to surgically set bifrontal width.

METHODS

A retrospective review of all trigonocephaly repairs was performed. Exclusion criteria included syndromic conditions, incomplete records, and follow-up under 1 year. Anthropometric measurements taken through completion of growth were evaluated and compared to sex- and age-matched normal standards for Z score conversion.

RESULTS

Of 370 consecutive patients undergoing repairs, 95 had sufficient anthropometric data. The mean surgical age was 10.8 months (range, 2 months to 7 years) and mean follow-up was 54.3 months (range, 12 months to 17.8 years). Sequential measurements revealed progressive increases in bifrontal width. However, following conversion to Z scores, the initial overcorrection (mean overcorrection, 8.7 mm; mean Z score, +2.3) steadily diminished to an undercorrection (mean measurement, -5.5 mm; mean Z score, -1.1). Compared to treatment at an older age (10 to 12 months), repairs performed in those younger than 8 months showed worse growth (p = 0.004). Those more severely affected (lowest bifrontal Z scores) had growth similar to that of those more mildly impacted. Only two patients (2.1 percent) underwent secondary procedures for recurrences. No correlation was found between anthropologic measurements and observers' severity assessments.

CONCLUSIONS

Subnormal bifrontal growth occurs following trigonocephaly corrections, especially with earlier corrections. Repairs performed at approximately 11 months of age had to be overcorrected by approximately 1.5 cm to produce a normal bifrontal width at maturity.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.