title: Fluorescence-guided resection with 5-aminolevulinic Acid of subependymomas of the fourth ventricle: report of 2 cases: technical case report.
abstract: BACKGROUND
  The usefulness of 5-aminolevulinic acid (5-ALA) for resection of malignant astrocytomas has been established in recent years. In addition to these tumors, it has been reported that 5-ALA fluorescence could be elicited in other tumors such as intracranial and spinal meningiomas or posterior fossa and spinal cord ependymomas, resulting in improved resections. Here, we present 2 cases of subependymomas of the fourth ventricle that showed intense fluorescence after 5-ALA administration. To the best of our knowledge, these are the first reported cases of subependymomas in this location in which 5-ALA elicited useful fluorescence.
  
  
  METHODS
  Case 1 was a 61-year-old woman with a history of headaches accompanied by vomiting in the last month. Magnetic resonance imaging (MRI) revealed a tumor occupying the fourth ventricle with slight irregular enhancement. She was operated on after administration of 5-ALA. The tumor emitted intense red fluorescence when illuminated with blue light. An MRI performed 48 hours after surgery confirmed complete resection of the tumor. The pathological diagnosis was subependymoma. Case 2 was a 35-year-old man with a history of several months of headaches and vomiting. An MRI revealed a tumor occupying the caudal part of the fourth ventricle with moderate and irregular enhancement. He was operated on after administration of 5-ALA. The tumor showed intense fluorescence. An MRI performed 48 hours after surgery confirmed a complete resection of the tumor. The pathological diagnosis was subependymoma.
  
  
  CONCLUSIONS
  Fluorescence-guided resection with 5-ALA may be useful for resection of subependymomas of the fourth ventricle. However, further studies are needed.
authors.affiliation: Departments of *Neurosurgery and ‡Intensive Care, University Hospital Infanta Cristina, Badajoz, Spain.
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: Bernal García
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Cabezudo Artero
authors.forename: María Bella
authors.initials: MB
authors.lastname: Marcelo Zamorano
authors.forename: Ignacio
authors.initials: I
authors.lastname: Gilete Tejero
mesh_terms: D000328:Adult; D000622:Aminolevulinic Acid; D002551:Cerebral Ventricle Neoplasms / Q000601:surgery*; D005260:Female; D005453:Fluorescence; D020546:Fourth Ventricle / Q000601:surgery*; D018315:Glioma, Subependymal / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D025321:Surgery, Computer-Assisted / Q000379:methods*
chemical_list: D000622:Aminolevulinic Acid