Incidental findings on preoperative computed tomography for nonsyndromic single suture craniosynostosis

Although the diagnosis of nonsyndromic single suture craniosynostosis (NSSC) can usually be made by clinical examination, computed tomography (CT) is still commonly used in preoperative evaluation. This practice has been questioned in light of recent studies that document a small, but measurable, increased risk of malignancy from CT-associated radiation. The purpose of this study was to examine whether preoperative CT for patients with NSSC provided clinically important information beyond confirmation of craniosynostosis. We performed a retrospective analysis of all patients with NSSC undergoing cranial vault remodeling at our center from March 1999 to March 2011. Only patients with complete preoperative CT scans available for review were included. Staff pediatric neurosurgeons were blinded to patient diagnosis and official radiology report, analyzed the CT images, and documented the site of synostosis and any other findings. Of the 231 patients, 80 met the inclusion criteria. Sites of synostosis included sagittal (51 patients), coronal (17 patients), metopic (11 patients), and frontosphenoidal (1 patient). Clinical diagnosis correlated with radiographic site of fusion in all patients except the patient with frontosphenoidal synostosis. Incidental findings were documented in more than 50% of the patients including prominent extra-axial cerebrospinal fluid (n = 36, 45%), ventriculomegaly (n = 5, 6.25%), choroid fissure cyst (n = 2), cavum septum pellucidum (n = 2), Chiari malformation (n = 1), and prominent perivascular space (clinically nonsignificant finding, n = 1). Incidental findings required additional follow-up or management in 5 patients (6.25%). Our findings support the use of preoperative imaging in this population to identify intracranial anomalies that cannot be discerned by clinical examination. Whereas many findings were not clinically important, some required additional attention.