Following the resection of newly diagnosed or recurrent glioblastomas, local 
implantation of carmustine-impregnated biodegradable wafers (Gliadel) in the 
resection cavity constitutes an adjuvant therapy that can improve the 
possibilities of survival. However, some precautions should be taken regarding 
Gliadel implantation. We report three cases in whom patients with glioblastoma 
multiforme were implanted with fibrin glue-secured Gliadel after the lateral 
ventricles had been opened, and who later developed severe hydrocephalus leading 
to death. Although Gliadel may be an important adjunct to treatment, opening of 
the ventricles during surgery as part of its application should be considered a 
contra-indication.