title: Comparison of liquid crystal display monitors calibrated with gray-scale standard display function and with γ 2.2 and iPad: observer performance in detection of cerebral infarction on brain CT.
abstract: OBJECTIVE
  The purpose of the study was to compare observer performance in the detection of cerebral infarction on a brain CT using medical-grade liquid crystal display (LCD) monitors calibrated with the gray-scale standard display function and with γ 2.2 and using an iPad with a simulated screen setting.
  
  
  METHODS
  We amassed 97 sample sets, from 47 patients with proven cerebral infarction and 50 healthy control subjects. Nine radiologists independently assessed brain CT on a gray-scale standard display function LCD, a γ 2.2 LCD, and an iPad in random order over 4-week intervals. Receiver operating characteristic (ROC) analysis was performed by using the continuous scale, and the area under the ROC curve (A(z)) was calculated for each monitor.
  
  
  RESULTS
  The A(z) values for gray-scale standard display function LCD, γ 2.2 LCD, and iPad were 0.875, 0.884, and 0.839, respectively. The difference among the three monitors was very small. There was no significant difference between gray-scale standard display function LCD and γ 2.2 LCD. However, the A(z) value was statistically significantly smaller for the iPad than the γ 2.2 LCD (p < 0.05).
  
  
  CONCLUSIONS
  Observer performance for detecting cerebral infarction on the LCD with γ 2.2 calibration was found to be similar to the LCD with gray-scale standard display function calibration. Although observer performance using the iPad was poorer than that using the other LCDs, the difference was small. Therefore, the iPad could not substitute for other LCD monitors. However, owing to the promising potential advantages of tablet PCs, such as portability, further examination is needed into the clinical use of tablet PCs.
authors.affiliation: Department of Radiological Sciences, Nagoya University Graduate School of Medicine, 1-20 Daikominami 1 chome, Higashi-ku, Nagoya, Aichi 461-8673, Japan. yosimura@met.nagoya-u.ac.jp
authors.forename: Kumiko
authors.initials: K
authors.lastname: Yoshimura
authors.forename: Takashi
authors.initials: T
authors.lastname: Nihashi
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Ikeda
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Ando
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kawai
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kawakami
authors.forename: Reiko
authors.initials: R
authors.lastname: Kimura
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Okada
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Okochi
authors.forename: Naotoshi
authors.initials: N
authors.lastname: Ota
authors.forename: Kenichi
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
mesh_terms: D000704:Analysis of Variance; D002138:Calibration; D016022:Case-Control Studies; D002544:Cerebral Infarction / Q000000981:diagnostic imaging*; D034201:Computers, Handheld; D005260:Female; D006801:Humans; D050866:Liquid Crystals; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging; D012372:ROC Curve; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed / Q000379:methods*