Multifocal objective pupil perimetry in migraine

Abstract

Purpose : To establish the effect of stimulating intrinsically-photosensitive retinal ganglion cells (ipRGCs) on migraine occurrence and pupillary response characteristics.

Methods : A randomized crossover study tested migraineurs and normal controls using multifocal pupillographic objective perimetry (mfPOP) with 44 test-regions/eye. A blue protocol (BP) stimulated the ipRGC intrinsic response, and a yellow protocol (YP) stimulated cone photoreceptors. The stimuli have been previously described [IOVS 56:6394-6403] Migraine diaries assessed migraine incidence. Responses were analysed according to response time-to-peak and standardised amplitude (AmpStd). Subjects included 38 migraineurs (42.0 ± 16.0 years, 23 females) and 24 normal controls (39.2 ± 14.8 years,14 females).

Results : Migraine days/week did not change following testing with either protocol. Pupillary responses were similar between migraineurs and controls. Amongst migraineurs an attack occurring 60 days before testing reduced AmpStd by -0.45 ± 0.16 dB for BP, (p < 0.004); two weeks before by -0.64 ± 0.14 dB for BP and 0.65 ± 0.11 dB for YP (both p < 0.001); and 1 week before by 0.80 ± 0.10 dB for BP, and 0.57 ± 0.08 dB for BP (both p < 0.001). Triptan use increased AmpStd by 0.45 ± 0.09 and 0.48 ± 0.07dB for YP and BP respectively (p = 0.001).

Conclusions : Pupillary response characteristics were influenced by both recent migraine attacks and triptan use. Stimulating ipRGCs did not affect migraine incidence but responses to blue stimuli may be affected for longer post-migraine.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.