title: Early Postoperative Expansion of Parenchymal High-intensity Areas on T2-weighted Imaging Predicts Delayed Cerebral Edema Caused by Carmustine Wafer Implantation in Patients with High-grade Glioma.
abstract: BACKGROUND
  Carmustine (BCNU) wafer (Gliadel(®) Wafer) implantation after tumor resection is an approved treatment for high-grade glioma (HGG). These wafers change various characteristics on early postoperative magnetic resonance imaging (ep-MRI) including slight expansion of high-intensity areas on T2-weighted imaging (ep-T2-HIAs) into adjacent parenchyma without restricted diffusivity. We assessed the frequency of the ep-T2-HIAs after BCNU wafer implantation in HGG patients. Moreover, we focused on ep-T2-HIA expansion and its relation to delayed cerebral edema.
  
  
  METHODS
  Twenty-five consecutive HGG patients who underwent BCNU wafer implantation were assessed. First, patients were divided into ep-T2-HIA and non-ep-T2-HIA groups, and the incidence of delayed adverse effects was compared between the two groups. Subsequently, the patients were divided into delayed edema and non-delayed edema groups, and pre-, intra-, and postoperative data were compared between the two groups.
  
  
  RESULTS
  The ep-T2-HIA expansion and the delayed edema were evident in 9 cases (36%) and 12 cases (48%), respectively. In comparison of the ep-T2-HIA and non-ep-T2-HIA groups, delayed edema was the only delayed adverse effect associated with ep-T2-HIA expansion (P = 0.004). Univariate analysis showed a significantly higher ratio of delayed edema in the subgroups with maximal diameter of removed cavity ≤40 mm (P = 0.047) and the ep-T2-HIA expansion in comparison of the delayed edema and non-delayed edema groups. Multivariate analysis showed that the ep-T2-HIA expansion was the only independent factor associated with delayed edema (P = 0.021).
  
  
  CONCLUSIONS
  In BCNU wafer implantation cases, ep-T2-HIA expansion was a predictive factor for delayed cerebral edema.
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, University of Tsukuba.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Masuda
authors.forename: Eiichi
authors.initials: E
authors.lastname: Ishikawa
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Masahide
authors.initials: M
authors.lastname: Matsuda
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Akutsu
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Kohzuki
authors.forename: Kei
authors.initials: K
authors.lastname: Nakai
authors.forename: Emiko
authors.initials: E
authors.lastname: Okamoto
authors.forename: Shingo
authors.initials: S
authors.lastname: Takano
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Masumoto
authors.forename: Akira
authors.initials: A
authors.lastname: Matsumura
mesh_terms: D000328:Adult; D000368:Aged; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use*; D001929:Brain Edema / Q000000981:diagnostic imaging / Q000209:etiology*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002330:Carmustine / Q000627:therapeutic use*; D005260:Female; D005910:Glioma / Q000150:complications* / Q000188:drug therapy* / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D000072356:Parenchymal Tissue / Q000000981:diagnostic imaging; D012189:Retrospective Studies
chemical_list: D018906:Antineoplastic Agents, Alkylating; D002330:Carmustine