title: Assessment of Central Retinal Sensitivity Employing Two Types of Microperimetry Devices.
abstract: OBJECTIVE
  To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Perimeter 1 (MP-1) and the Optos optical coherence tomography (OCT)/scanning laser ophthalmoscope (SLO) in subjects with and without maculopathies.
  
  
  METHODS
  Forty-five eyes with no known ocular disease and 47 eyes with maculopathies were examined using both microperimeters. A contrast-adjusted scale was applied to resolve the different stimuli and background luminance existing between the two devices.
  
  
  RESULTS
  There was a strong ceiling effect with the MP-1 in the healthy group, with 90.1% (1136 of 1260) test points clustered at 20 dB. The mean sensitivity for the corresponding points in the OCT/SLO was 25.8 ± 1.9 dB. A floor effect was also observed with the OCT/SLO in the maculopathy group with 9.7% (128 of 1316) points clustered at 9-dB values. The corresponding mean sensitivity in the MP-1 was 1.7 ± 3.9 dB. A regression equation between the two microperimeters was established in the common 10 to19 dB intervals as: OCT/SLO = 15.6 + 0.564 × MP-1 - 0.009 × MP-12+k(kis an individual point constant; MP-1 coefficientP< 0.001; MP-12coefficientP= 0.006).
  
  
  CONCLUSIONS
  The OCT/SLO and the MP-1 provide two different ranges of contrasts for microperimetry examination. Broadening the dynamic range may minimize the constraint of the ceiling and floor effect. There is a significant mathematical relationship in the common interval of the contrast scale.
  
  
  CONCLUSIONS
  Applying a unified and broadened dynamic range in different types of microperimeters will help to generate consistent clinical reference for measurements.
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD ; Visual Science and Optometry Center, People's Hospital of Guanxi Zhuang Autonomous Region, Nanning, Guangxi province, China.
authors.forename: Hongting
authors.initials: H
authors.lastname: Liu
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD.
authors.forename: Millena G
authors.initials: MG
authors.lastname: Bittencourt
authors.affiliation: Department of Biostatistics, School of Public Health, Johns Hopkins University, Baltimore, MD.
authors.forename: Jiangxia
authors.initials: J
authors.lastname: Wang
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD.
authors.forename: Raafay
authors.initials: R
authors.lastname: Sophie
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD.
authors.forename: Rachel
authors.initials: R
authors.lastname: Annam
authors.affiliation: Stanley M. Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, NE.
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Ibrahim
authors.affiliation: Stanley M. Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, NE.
authors.forename: Yasir J
authors.initials: YJ
authors.lastname: Sepah
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD.
authors.forename: Ahmadreza
authors.initials: A
authors.lastname: Moradi
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD.
authors.forename: Hendrik P N
authors.initials: HP
authors.lastname: Scholl
authors.affiliation: Stanley M. Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, NE.
authors.forename: Quan Dong
authors.initials: QD
authors.lastname: Nguyen
keywords: comparison; microperimetry; retinal sensitivity