Intracranial Pressure, Autoregulation, and Cerebral Perfusion in Infants With Nonsyndromic Craniosynostosis at the Time of Surgical Correction

Abstract

BACKGROUND AND OBJECTIVE: Although an increased intracranial pressure (ICP) is a known problem in children with syndromic craniosynostosis, it remains unclear whether elevated ICP and impaired cerebral perfusion exist in nonsyndromic synostosis and should be defined as targets of primary treatment. This study aimed to investigate ICP, cerebral autoregulation (CAR), and brain perfusion in infants with nonsyndromic craniosynostosis at first surgical intervention. METHODS: Forty-three infants were prospectively included. The patients underwent perioperative measurement of mean arterial blood pressure, ICP, and brain perfusion before and after cranial vault decompression. Physiological parameters with possible influences on ICP and autoregulation/brain perfusion were standardized for age. CAR was assessed by the pressure reactivity index (PRx), calculated using the mean arterial blood pressure and ICP. RESULTS: Biparietal decompression was performed in 29 infants with sagittal synostosis (mean age, 6.1 ± 1.3 months). Fronto-orbital advancement was performed in 10 and 4 infants with metopic and unilateral coronal synostosis, respectively (mean age, 11.6 ± 2.1 months). An elevated ICP (>15 mm Hg) was found in 20 of 26 sagittal (mean, 21.7 ± 4.4 mm Hg), 2 of 8 metopic (mean, 17.1 ± 0.4 mm Hg), and 2 of 4 unilateral coronal synostosis cases (mean, 18.9 ± 2.5 mm Hg). Initial ICP was higher in sagittal synostosis than in metopic/coronal synostosis (P = .002). The postdecompression ICP was significantly reduced in sagittal synostosis cases (P < .001). The relative cerebral blood flow and blood flow velocity significantly increased after decompression. Impaired CAR was found in infants with a mean ICP >12 mm Hg (PRx, 0.26 ± 0.32), as compared with those with a mean ICP ≤ 12 mm Hg (PRx, −0.37 ± 0.07, P = .001). CONCLUSION: Contrary to common belief, an elevated ICP and significantly impaired CAR can exist early in single suture synostosis, particularly sagittal synostosis. Because an influence of raised ICP on long-term cognitive development is known in other diseases, we suggest that preventing increased ICP during the phase of maximal brain development may be a goal for decompressive surgery, at least for sagittal synostosis cases.