title: Transient pupillary light reflex in relation to fundus autofluorescence and dark-adapted perimetry in typical retinitis pigmentosa.
abstract: OBJECTIVE
  To determine whether the pupillary light reflex (PLR) can serve as an indicator of photoreceptor function in patients with advanced typical retinitis pigmentosa (RP).
  
  
  METHODS
  Dark-adapted transient PLRs elicited by blue or white light over a luminance range of 4 log units were recorded from 27 eyes of 19 patients with advanced RP. Retinas were characterized according to fundus autofluorescence (AF) and dark-adapted perimetry. We qualitatively analyzed whether PLR thresholds were correlated with AF patterns or scotopic sensitivity. Quantitative analysis included correlations between relative pupillary constrictions (RPCs) elicited by blue light (≤-1 log cd/m(2)) and the area of abnormal ring or central AF, and between RPCs elicited by white light and perimetric mean sensitivity.
  
  
  RESULTS
  The PLRs of all patients showed varying degrees of threshold elevation and relative afferent pupil defects. We classified three types of abnormal fundus AF: abnormal ring AF, abnormal central AF, and fragmentary AF. PLR thresholds were largely consistent with the patterns of AF and scotopic sensitivity. Rod-mediated RPCs were not correlated with the area of the abnormal ring AF (p > 0.05), but were correlated with the area of abnormal central AF (p < 0.05). RPCs elicited with a white stimulus (-0.3 or 0.7 log cd/m(2)) were significantly correlated with the mean sensitivity of the dark-adapted perimetry.
  
  
  CONCLUSIONS
  PLR testing is a powerful technique for assessing photoreceptor dysfunction. The high correlation with AF and dark-adapted perimetry suggests that the key to quantifying photoreceptor function using the transient PLR is to optimize the luminance of the stimulus.
authors: Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing, China.
authors: Yong
authors: Y
authors: Liu
authors: Dan Ning
authors: DN
authors: Liu
authors: Xiao Hong
authors: XH
authors: Meng
authors: Zheng Qin
authors: ZQ
authors: Yin
mesh_terms: D000328:Adult; D003623:Dark Adaptation / Q000502:physiology*; D005260:Female; D005453:Fluorescence; D005654:Fundus Oculi; D006801:Humans; D008027:Light; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D012025:Reflex, Pupillary / Q000502:physiology*; D012160:Retina / Q000503:physiopathology*; D012174:Retinitis Pigmentosa / Q000503:physiopathology*; D012684:Sensory Thresholds / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology*; D055815:Young Adult