title: [Evaluation on the noninvasive measurement of macular pigment optical density by a novel technique].
abstract: OBJECTIVE
  To evaluate the measurement of macular pigment optical density (MPOD) by a novel instrument MPS1000 as compared to that measured by the traditional heterochromatic flicker photometer (HFP).
  
  
  METHODS
  Method-comparative study. MPOD at 0.5° eccentricity was measured simultaneously by the two different instruments in 111 eyes of the 59 healthy subjects. Test-retest variability was evaluated for each instrument over a 1-week period in 8 subjects.
  
  
  RESULTS
  The mean MPOD levels measured by the MPS1000 and HFP were 0.40±0.18 and 0.47±0.15, respectively, which were statistically significantly different by the paired t-test (t=3.95, P<0.001). A positive linear correlation was observed for MPOD at 0.5° eccentricity between the two different instruments (r=0.4, P<0.001). The 95% limit of agreement was 0.07±0.35 as shown by Bland-Altman analysis. Intersessional repeatability, expressed as a coefficient of repeatability, was 0.26 for HFP and 0.18 for MPS1000.
  
  
  CONCLUSIONS
  MPOD levels measured by MPS1000 were significantly higher as compared to that measured by the traditional HFP, suggesting that it is inappropriate to directly compare the MPOD levels measured by these two methodologies.
authors: Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
authors: Xu
authors: X
authors: Han
authors: Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
authors: Xuetao
authors: X
authors: Ren
authors: Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
authors: Xue
authors: X
authors: Li
authors: Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
authors: Junyan
authors: J
authors: Zhang
authors: Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
authors: Jie
authors: J
authors: Yu
authors: Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China; Email: nliu001@gmail.com.
authors: Ningpu
authors: N
authors: Liu
mesh_terms: D006801:Humans; D065348:Macular Pigment / Q000032:analysis*; D010783:Photometry / Q000295:instrumentation / Q000379:methods*
chemical_list: D065348:Macular Pigment