title: A Decrease in the Volume of Gray Matter as a Risk Factor for Postoperative Delirium Revealed by an Atlas-based Method.
abstract: Delirium is a common syndrome in older patients after surgery. Although an atrophic change in the whole brain may be a potential risk factor for postoperative delirium, the anatomically specific change related to the vulnerability still remains a significant issue.
  
  
  
  Prospective study.
  
  
  
  University hospital.
  
  
  
  116 consecutive patients who underwent elective cardiac operations.
  
  
  
  Before the surgery, magnetic resonance imaging (MRI) was evaluated. The MRI data were processed to calculate the absolute volumes of the predefined region of interest using Statistical Parametrical Mapping 8 with an atlas-based method. The evaluated volume was expressed as the fraction (%) of the total intracranial volume. Postoperative delirium was diagnosed according to the DSM-IV criteria for delirium.
  
  
  
  Delirium developed in 19 of 116 patients (16.4%) with an age range from 58 to 84 years. Based on a comparison with the age-controlled non-delirium patients (over 57 years; n = 65), a statistically significant reduction in the gray matter volume of the delirium patients was observed in the defined gyri of the temporal and limbic lobes. Moreover, a moderate value (>0.8) of area under the curve to predict postoperative delirium was revealed by receiver operating characteristic curve analysis of the gyri of temporal lobe.
  
  
  
  The decreased volume of gray matter could be associated with the vulnerability to delirium after surgery. The atlas-based method would be a potential tool to pre-screen the brain structure of individual patients for the prediction of postoperative delirium.
authors.affiliation: Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, Tokyo, Japan. Electronic address: 0724.psyc@tmd.ac.jp.
authors.forename: Akiko
authors.initials: A
authors.lastname: Shioiri
authors.affiliation: Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Akeo
authors.initials: A
authors.lastname: Kurumaji
authors.affiliation: Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Takeuchi
authors.affiliation: Department of NeuropsychiatryInstitute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Nemoto
authors.affiliation: Department of Cardiovascular Surgery, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Hirokuni
authors.initials: H
authors.lastname: Arai
authors.affiliation: Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Nishikawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001284:Atrophy / Q000473:pathology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D016022:Case-Control Studies; D003693:Delirium / Q000453:epidemiology* / Q000209:etiology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging* / Q000473:pathology*; D006785:Hospitals, University; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000453:epidemiology*; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D013702:Temporal Lobe / Q000473:pathology
keywords: Atlas-based; Brain MRI; Delirium; Predisposing factors; ROC curve analysis