The mainstay of treatment for single-suture cranial synostosis is cranial vault reconstruction. After primary cranial vault remodeling, patients are at risk for cranial restenosis and delayed intracranial hypertension, which may result in developmental delay or blindness. Synostosis patients are therefore generally monitored periodically for signs and symptoms of intracranial hypertension that may indicate a second cranial expansion procedure. The authors present a carefully illustrated case of a patient who presented 2 years after primary cranial vault reconstruction for sagittal synostosis with a decrease in head circumference percentile, recurrent cranial dysmorphism, papilledema, headaches and computed tomographic imaging findings consistent with cranial restenosis. These findings resolved after secondary cranial vault remodeling. The authors advocate a protocol of prospective routine clinical and radiographic follow-up after primary cranial vault repair for single-suture cranial synostosis, and illustrate the specific clinical and radiographic findings suggestive of this late complication in a representative individual patient.