Effect of molding helmets on intracranial pressure and head shape in nonsurgically treated sagittal craniosynostosis patients

Abstract

OBJECTIVE Cranial vault expansion is performed in pediatric patients with craniosynostosis to improve head shape. Another argument for performing total cranial vault reconstruction is the potential reduction in the harmful effects of elevated intracranial pressure (ICP) that are associated with craniosynostosis. Alternatively, molding helmets have been shown to improve the cranial index (CI) in patients with sagittal synostosis without surgery. However, it is unknown if the use of molding helmets without surgery contributes to adverse changes in ICP. The effect of molding helmets on ICP and CI in patients with sagittal synostosis was investigated. METHODS A prospective cohort study of 24 pediatric patients with sagittal synostosis who planned to undergo total cranial reconstruction was performed from 2011 to 2014 at the Children's Hospital of Michigan. A preoperative molding helmet was used in 13 patients, and no molding helmet was used in 11 patients. End-tidal carbon dioxide, patient positioning, level of sedation, type of anesthetic, and the monitoring site at the time of intraoperative recording were regulated and standardized to establish the accuracy of the ICP readings. CI and head circumference were monitored for each patient. RESULTS The mean duration of the preoperative use of the molding helmet was 17 weeks (range 7-37 weeks). Under controlled settings, the average intraoperative ICP was 7.2 mm Hg (range 2-18 mm Hg) for patients treated with a preoperative molding helmet and 9.5 mm Hg (range 2-22 mm Hg) for patients with no preoperative molding helmet. ICP was not significantly different between the 2 groups, suggesting that the use of a molding helmet in this population is safe. The average CI at the time of helmet placement was 0.70 (range 0.67-0.73), and this improved to an average of 0.74 (range 0.69-0.79) after using the molding helmet for a mean of 17 weeks. CONCLUSIONS ICPs were not significantly different with the use of a preoperative molding helmet, refuting the prevailing thought that molding helmets would be detrimental in children who have craniosynostosis. The use of molding helmet in this population of patients improves head shape and does not adversely affect ICP.

Keywords: CI = cranial index; ICP = intracranial pressure; MAC = minimum alveolar concentration; REM = rapid eye movement; TCR = total cranial reconstruction; craniofacial; craniosynostosis; intracranial pressure; molding helmet; sagittal synostosis; scaphocephaly.