Intracranial compartment volume changes in sagittal craniosynostosis patients: influence of comprehensive cranioplasty.

ABSTRACT

BACKGROUND: A retrospective analysis of intracranial compartment volume changes in children with sagittal craniosynostosis was performed to clarify the therapeutic objectives of corrective surgery. METHODS: Chart and computed tomographic review of 53 consecutive children with previously unoperated sagittal synostosis was performed, and preoperative and postoperative computed tomographic scans were examined and compared with 143 age- and gender-matched controls. RESULTS: Preoperative mean intracranial compartment volume and mean brain tissue volume of each subgroup were age dependent. Brain volume was less in unoperated male sagittal synostosis patients (<6 months old) compared with controls (672.63 ml versus 716.14 ml). Brain tissue volume was approximately the same as controls for the 7- to 12-month and 12- to 30-month age groups. Long-term brain volume, however, again became less than controls with longer periods without treatment (31 to 60 months, 1050.6 versus 1291.51 ml, respectively). Intracranial compartment volume was less in unoperated male sagittal synostosis patients (<6 months old) compared with controls (706.6 ml versus 757.76 ml). Preoperative mean intracranial compartment volume, however, was greater than in controls in the 7- to 12-month (979.78 versus 970.34 ml) and 13- to 30-month age groups (1108.23 versus 1177.52 ml). Long term (31 to 60 months), however, intracranial compartment volume was less in untreated sagittal synostosis patients (1206.3 ml versus 1311.37 ml). Comparing day-1 postoperative sagittal synostosis patient data to age- and gender-matched controls to 1 year postoperatively, the operated patients develop an equivalent increase in skull growth compared with normals. CONCLUSIONS: Intracranial compartment volume is increased preoperatively in untreated sagittal synostosis patients older than 6 months. Intracranial compartment volume enlargement is largely attributable to an increase in brain volume. Comprehensive cranioplasty before 12 months of age increases intracranial compartment volume over normal growth.