Recovery dynamics of multifocal pupillographic objective perimetry from tropicamide dilation
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To study the pupillary system by combining mydriasis and multifocal pupillographic objective perimetry (mfPOP). In particular, we explored how the dynamics of recovery differ for concurrently measured direct and consensual sensitivity, response delay, and signal-to-noise ratios (SNRs) for binocular mydriasis.
We recruited 26 normal participants, all with brown irides. The dichoptic mfPOP stimuli concurrently assessed 44-region/eye and both pupils. Two pre-dilation tests were followed by pairs of repeated tests at 1, 2, 4, 6, 8, 12, 24, and 48 h following dilation of both pupils with 1% tropicamide. Three subjects were retested with only the right pupil dilated. Linear models determined the independent effects of mydriasis upon the per-region and pupil measures over time.
Post-dilation, the per-region delays initially decreased by 16.3 ± 6.02 ms (mean ± SE) (p < 0.0001, cf. baseline of 471.1 ± 4.36 ms), then increased to slower than baseline by 17.42 ± 5.57 ms after 4 h (p < 0.002), recovering to baseline at 8 h. By comparison, per-region sensitivities (constriction amplitudes) were still reduced by − 6.20 ± 0.70 μm at 8 h (p < 0.0001, cf. baseline of 21.1 ± 0.55 μm), recovered at 24 h, but rebounded at 48 h (p = 0.005). The SNRs for sensitivities and delays both recovered by 8–12 h. Across all the data, sensitivities reduced by 2.67 ± 0.25 μm/decade of age, and delay increased by 15.4 ± 1.98 ms/decade (both p < 0.00001). Data from 3 of the 26 subjects who repeated the testing for monocular dilation found that consensual response sensitivities were larger than direct for 8 h (p < 0.018).
The per-region sensitivities were affected for longer than SNRs or delays. Strong early SNRs indicated proportionately lower pupil noise for larger pupil diameters. Following mydriasis with tropicamide 1%, the constriction amplitude measurements with mfPOP should be considered only after 48 h, but time-to-peak can be measured after 8–12 h.
KeywordsAnisocoria Multifocal Objective perimetry Pupillography Rebound miosis Tropicamide
This research was supported by the Australian Research Council through the ARC Centre of Excellence in Vision Science (CE0561903), intramural funding from the ANU, and an ANU PhD scholarship to BB Rai.
Compliance with ethical standards
Conflict of interest
Authors FS, CFC, JvK, and TM could possibly receive royalty income from patents assigned to Konan Medical USA Inc. for a possible product based upon the mfPOP methods. The other authors declare that they have no conflict of interest.
Ethical approval and informed consent
All procedures performed in studies involving human participants were in accordance with the ethical standards of the Australian National University and ACT Health and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants included in the study.
- 7.Carle CF, James AC, Rosli Y, Maddess T (2019) Localization of neuronal gain control in the pupillary response. Front Neurol 10(203):1–9Google Scholar
- 11.Cooper J, Feldman JM, Jaanus SD, Appleman W, Appel S, Horn D (1996) Pupillary dilation and funduscopy with 1.0% hydroxyamphetamine plus 0.25% tropicamide (Paremyd) versus tropicamide (0.5 or 1.0%) as a function of iris and skin pigmentation, and age. J Am Optom Assoc 67(11):669–675PubMedGoogle Scholar
- 14.Ihekaire DE (2012) The comparative efficacy of cycloplegic drugs—tropicamide and cyclopentolate. Int J Sci Res Educ 5(3):223–246Google Scholar
- 17.Drugs.com (2017) Tropicamide: FDA prescription information. www.drugs.com/pro/tropicamide.html. Accessed 15 Dec 2017
- 29.Schmid R, Wilhelm H, Wilhelm B, Kriegbaum C, Miliczek K, Wannek U (1995) Naso-temporal differences in pupillomotor sensitivity. Invest Ophthalmol Vis Sci 37:159Google Scholar
- 34.Miller D, Stark L (1964) Effect of mydriatic drugs on pupil dynamics. Res Lab Elec MIT Q Prog Rep 74:265–269Google Scholar