Intracranial migration of a ventriculoperitoneal shunt: A case report and literature review

Abstract

Background: The intracranial migration of a ventriculoperitoneal shunt (VPS) has been previously described, it is a very rare event, and the mechanisms of this migration have not yet been elucidated.

Case description: Newborn at 38 weeks of gestation by cesarean section, with congenital hydrocephalus due to Dandy-Walker malformation that required right Frazier VPS placement. At 2-month follow-up, computed tomography of the skull showed cranial migration of VPS and dysfunction. At evaluation, there were signs of systemic infection. External ventricular drainage was placed and an intravenous antibiotic scheme for Gram-positive bacteria was started. After 3 months, cerebrospinal fluid cultures were negative and definitive VPS was decided.

Conclusion: Different possible mechanisms have been proposed, such as negative intraventricular pressure, positive intra-abdominal pressure, use of valveless catheters, excessive burr hole size, as well as such as occipital ventricular access, thin cortical mantle, incorrect distal and proximal fixation, short distance between the peritoneum and ventricles, and a possible inflammatory reaction to the catheter material (silicone). A combination of these different mechanisms contributes to proximal shunt migration. Although the placement of a VPS is a procedure well taught since the 1^st years of neurosurgical residency, it is not exempt from complications. Although, as was previously stated in this paper, the incidence of a complete cranial VPS migration is extremely rare, and only a few cases are documented, it is still important to report this type of cases and to try to elucidate the possible mechanisms involved.

Keywords: Complications; Migration; Ventriculoperitoneal shunt.

Figure 1:

Non-contrast computed tomography scan that shows a fourth ventricle cyst compatible with Dandy–Walker syndrome, and radiological signs of hydrocephalus.

Figure 2:

(a). X-ray 1 month after placement of the ventriculoperitoneal shunt. The blue arrow shows the situation of the system reservoir which is in the extracranial subgaleal space, a bulging in the scalp is noticed. (b). X-ray 2 months after placement of the ventriculoperitoneal shunt. The blue arrow shows the cranial migration of the system.

Figure 3:

Non-contrast computed tomography scan axial, sagittal, and coronal planes. The whole shunt system is in the intracranial space.

Figure 4:

3D reconstruction of the simple computed tomography (CT) scan. Blue arrows show the first ventriculoperitoneal system that is in the intracranial space. Yellow arrow shows a second ventriculoperitoneal shunt which is dysfunctional as it is shown in the CT scan.

Figure 5:

Intraoperative images showing extraction of the ventriculoperitoneal shunt system.

Figure 6:

Non-contrast computed tomography scan that shows a functional ventriculoperitoneal shunt system.