title: Chemical meningitis after cerebral aneurysm treatment using two second-generation aneurysm coils: report of two cases.
abstract: OBJECTIVE
  In the quest for effective and durable endovascular aneurysm treatment, second-generation aneurysm coils endeavor to increase the biological healing response to the implanted material. We report two cases of large cerebral aneurysms treated concurrently with both available second-generation aneurysm coils and the subsequent development of symptomatic nonbacterial meningitis.
  
  
  METHODS
  Two previously healthy patients underwent endovascular treatment for large (>=2 cm) cerebral aneurysms. Both aneurysms were treated using multiple Hydrogel coils (MicroVention, Inc., Aliso Viejo, CA) and Matrix coils (Boston Scientific/Target, Fremont, CA). Careful aseptic technique was observed throughout each procedure, and prophylactic intravenous antibiotics were administered during the perioperative period to both patients. Treatment proceeded uneventfully in both cases with excellent aneurysm occlusion and no immediate postoperative neurological deficits.
  
  
  METHODS
  In both cases, the patients were discharged from hospital but quickly were readmitted with stigmata of meningitis. Imaging demonstrated durable occlusion of the aneurysms in both patients and also abnormalities indicative of perianeurysmal and diffuse intracranial inflammatory response. Complete septic workup failed to identify an organism in either patient. Both patients responded to treatment with corticosteroid medication used to modulate the inflammatory response induced by the coil implants.
  
  
  CONCLUSIONS
  Second-generation aneurysm coils were developed to promote more durable occlusion of cerebral aneurysms by promoting more complete volumetric aneurysm occlusion or by eliciting a more prolific inflammatory response. The concurrent use of Hydrogel and Matrix coil systems in large aneurysms may cause an exuberant inflammatory response with both local and systemic manifestations. Although vigilant evaluation and treatment for presumptive bacterial meningitis is required in all such cases, patients respond to immunomodulatory therapy with corticosteroids. More information to understand better the interaction of Hydrogel and Matrix coils is needed.
authors.affiliation: Departments of Radiology and Neurological Surgery, Neurological Institute, Columbia and Cornell University Medical Centers, 710 West 168th Street, New York, NY 10032, USA. pmm2002@columbia.edu
authors.forename: Philip M
authors.initials: PM
authors.lastname: Meyers
authors.forename: Sean D
authors.initials: SD
authors.lastname: Lavine
authors.forename: Brian-Fred
authors.initials: BF
authors.lastname: Fitzsimmons
authors.forename: Chris
authors.initials: C
authors.lastname: Commichau
authors.forename: Augusto
authors.initials: A
authors.lastname: Parra
authors.forename: Stephan A
authors.initials: SA
authors.lastname: Mayer
authors.forename: Robert A
authors.initials: RA
authors.lastname: Solomon
authors.forename: E Sander
authors.initials: ES
authors.lastname: Connolly
mesh_terms: D004621:Embolization, Therapeutic / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000628:therapy*; D008581:Meningitis / Q000139:chemically induced*; D008875:Middle Aged