Surgical management of craniosynostosis in the setting of a ventricular shunt: a case series and treatment algorithm

Abstract

Purpose: Cerebrospinal fluid diversion via ventricular shunt is a common treatment for hydrocephalus. Change in cranial morphology associated with a sutural fusion has been termed shunt-related or induced craniosynostosis (SRC) or craniocerebral disproportion (CCD). We present a series of patients with SRC who underwent cranial vault remodeling (CVR) and our treatment algorithm.

Methods: Thirteen patients were retrospectively reviewed who had SRC and CVR; 92% of patients had a ventriculoperitoneal (VP) shunt placed for largely intraventricular hemorrhage of prematurity (69% of patients) at a mean age of 2.2 months. The shunt revision rate was 38.4%, and 54% of patients had a programmable shunt placed initially.

Results: The mean age at time of CVR was 3.6 years old. The most commonly affected sutures (CT confirmed) were the sagittal and coronal sutures, with three patients exhibiting pancraniosynostosis. The mean time from placement of the shunt to CT evidence of sutural fusion was 2.0 years. Abnormal head shape was noted in all 13 patients; 11 of these also had either chronic headaches, papilledema, seizures, or behavioral changes in the setting of functional shunt. Mean follow-up after the initial CVR was 3.3 years. No shunt infections were attributed to the CVR. The families of all patients were contacted and reported improvement in head shape with 60% of families reporting improvement in behavior, 75% reported improvement in headaches, and 40% reported decrease in seizure frequency or intensity. Shunt setting or type was not routinely changed after CVR.

Conclusions: Our threshold for CVR in SRC is met when shunt malfunction has been ruled out and there are (1) radiographic evidence of craniosynostosis, (2) signs of increased ICP clinically or radiographically, and (3) cranial dysmorphism, i.e., dolichocephaly. The majority of cases of SRC result in improved cranial morphology in addition to some abatement of the symptoms of increased intracranial pressure. Early involvement of an experienced craniofacial/neurosurgical team could allow for early diagnosis and intervention which may prevent progression to more severe deformities. SRC is a complex entity, with multiple etiologies, and a future study is needed.

Keywords: Craniocerebral disproportion; Craniosynostosis; Ventricular shunt.