Characteristics of Postnatal Progressive Pansynostosis

Abstract

INTRODUCTION: Postnatal progressive pansynostosis (PPP) is uncommon. The insidious onset and relatively normal cranial shape often leads to delay in or failure of diagnosis. The risk of increased intracranial pressure (ICP) is significant. The purpose of this study was to review our series of patients with PPP to provide a more detailed description of this form of synostosis. METHODS: The authors reviewed their ongoing prospective craniofacial database (2/97-7/12) to document patients with PPP. Variables included age at diagnosis, syndromic association, head shape, serial head circumference (HC), radiographic findings, and operative interventions. Inclusion criteria included: 1) complete or partial fusion of all major cranial sutures on high resolution CT scan; 2) no prior craniofacial procedures at the time of CT diagnosis. RESULTS: A total of 10 out of 292 patients (3.5%) were identified. Each patient had confirmed fusion of all major cranial sutures. Mean age at diagnosis was 59.4 ± 42.3 months (range: 19-151 months). A syndrome was documented in 60% of patients, with Crouzon syndrome being most common (3 patients). Head shape was reported as normal or near normal in all patients. Serial HC, available in 90% of patients, documented sustained growth deceleration at the time of diagnosis. All patients had signs of increased ICP, such as severe endocortical erosion and loss of cisternal spaces; 6/7 patients with MRI had Chiari malformation. ICP monitoring in 4 patients revealed pressures ranging from 5 to >35 cm H2O. Calvarial expansion was performed in 70% of patients, two are awaiting definitive surgical repair, and one patient had only Chiari decompression and clinical monitoring. CONCLUSION: The gradual progression of fusion in PPP results in a slow decrease in head circumference percentile and a relatively normal head shape, leading to delayed diagnosis and increased ICP. There should be a high clinical index of suspicion in children with a known craniosynostosis syndrome (especially Crouzon syndrome) and normal head shape. Any sustained deceleration in serial HC should prompt CT evaluation.