Carmustine wafer implantation when surgical cavity is communicating with cerebral ventricles: technical considerations on a clinical series.

Background: Implantation of carmustine (1,3-bis (2 chloroetyl)-1-nitrosurea [BCNU]) wafers is an approved local treatment after surgical removal of high-grade gliomas. Safety data have been largely reported by phase III studies. The communication between the final surgical cavity and the ventricular cavities is supposed to be a relative contraindication for positioning of the wafers because of the possible development of hydrocephalus. However, at present there are neither data about this topic published with the exception of a few case reports, nor any proposals for selection criteria for wafer implantation in such circumstances. Furthermore, there are no technical suggestions in literature put forward for the surgical repairing of ventricular defects. Our study was particularly focused on addressing these 3 issues.

Methods: Forty-three patients affected by a high-grade glioma underwent surgical removal and BCNU wafer implantation between March 2007 and September 2009 at the Department of Neurosurgery of Padua. Among them, we retrospectively reviewed clinical, surgical, and radiological data of 9 patients who had been treated with carmustine wafers after surgical repair of communication between the surgical cavity and the ventricular cavities. We also focused on the technical details concerning wafers positioning in this particular situation.

Results: Ventricular defects were present in the atrium in 4, frontal horn in 3, and temporal horn in 2 cases. The maximum diameter of the defect was between 6 and 10 mm. In all cases, the defect was intraoperatively repaired in the same way, and up to 8 wafers were implanted in the surgical cavity. In the series reported, no cases of hydrocephalus were detected.

Conclusions: In our experience, integrity of wafers, size of ventricular wall defect, and accuracy in repairing the defect were crucial issues. Nevertheless, more experience and prospective studies would be helpful to clarify both in what measure ventricular opening affects safety data and the best reliable way of repairing ventricular defects when BCNU wafers are implanted.