title: Prognostic values of gray matter to white matter ratios on early brain computed tomography in adult comatose patients after out-of-hospital cardiac arrest of cardiac etiology.
abstract: OBJECTIVE
  Previous studies found that the gray matter to white matter ratio (GWR) on brain computed tomography (CT) could be used to predict poor outcomes in cardiac arrest survivors. However, these studies have included cardiac arrests of both cardiac and non-cardiac etiologies. We sought to evaluate if the GWR on brain CT can help to predict poor outcomes after out-of-hospital cardiac arrest (OHCA) of cardiac etiology.
  
  
  METHODS
  Using a multicenter retrospective registry of adult cardiac arrest survivors treated with therapeutic hypothermia, we identified survivors of OHCA of cardiac etiology who underwent brain CT within 24h after successful resuscitation. Gray and white matter attenuations were measured, and the GWRs were calculated as in previous studies. The prognostic values of the GWRs were analyzed, and a logistic regression analysis was performed to determine the contribution of the GWR in predicting poor outcomes (Cerebral Performance Category 3-5).
  
  
  RESULTS
  of 283 included patients, 140 had good outcomes and 143 had poor outcomes. Although the GWRs could predict poor outcomes with statistical significance, the sensitivities were remarkably low (3.5% to 5.6%) at cutoff values with 100% specificity. No significant difference in predictive performance was found between the primary predictive model, containing independent poor outcome predictors, and the primary predictive model combined with the GWR.
  
  
  CONCLUSIONS
  In a cohort of comatose adults after OHCA of cardiac etiology, the GWR demonstrated poor predictive performance and was not helpful in predicting poor outcomes.
authors.affiliation: Department of Emergency Medicine, Chonnam National University Medical School, 160, Baekseo-ro, Dong-gu, Gwangju, Republic of Korea. Electronic address: bbukkuk@hanmail.net.
authors.forename: Byung Kook
authors.initials: BK
authors.lastname: Lee
authors.affiliation: Department of Emergency Medicine, Chonnam National University Medical School, 160, Baekseo-ro, Dong-gu, Gwangju, Republic of Korea. Electronic address: neoneti@hanmail.net.
authors.forename: Kyung Woon
authors.initials: KW
authors.lastname: Jeung
authors.affiliation: Department of Emergency Medicine, Chonnam National University Medical School, 160, Baekseo-ro, Dong-gu, Gwangju, Republic of Korea. Electronic address: goodsongkh@hanmail.net.
authors.forename: Kyoung Hwan
authors.initials: KH
authors.lastname: Song
authors.affiliation: Department of Emergency Medicine, Chonnam National University Medical School, 160, Baekseo-ro, Dong-gu, Gwangju, Republic of Korea. Electronic address: xnxn77@hanmail.net.
authors.forename: Yong Hun
authors.initials: YH
authors.lastname: Jung
authors.affiliation: Department of Emergency Medicine, Ulsan University Hospital, 877, Bangeojinsunhwando-ro, Dong-gu, Ulsan, Republic of Korea. Electronic address: koreanermd@gmail.com.
authors.forename: Wook Jin
authors.initials: WJ
authors.lastname: Choi
authors.affiliation: Department of Emergency Medicine, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, Republic of Korea. Electronic address: unidgirl@catholic.ac.kr.
authors.forename: Soo Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Emergency Medicine, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, Republic of Korea. Electronic address: ycs1005@catholic.ac.kr.
authors.forename: Chun Sung
authors.initials: CS
authors.lastname: Youn
authors.affiliation: Department of Emergency Medicine, KEPCO Medical Center, 308, Uicheon-ro, Dobong-gu, Seoul, Republic of Korea. Electronic address: mensa@hanmail.net.
authors.forename: In Soo
authors.initials: IS
authors.lastname: Cho
authors.affiliation: Department of Emergency Medicine, Chonnam National University Medical School, 160, Baekseo-ro, Dong-gu, Gwangju, Republic of Korea. Electronic address: ggodhkekf@hanmail.net.
authors.forename: Dong Hun
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D003128:Coma / Q000150:complications* / Q000000981:diagnostic imaging / Q000401:mortality; D042241:Early Diagnosis; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging*; D006331:Heart Diseases / Q000150:complications* / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging / Q000379:methods*; D058687:Out-of-Hospital Cardiac Arrest / Q000000981:diagnostic imaging* / Q000209:etiology / Q000401:mortality; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D066127:White Matter / Q000000981:diagnostic imaging*
keywords: Brain; Edema; Heart arrest; Prognosis