Limits...
Effect of Age and Refractive Error on the Melanopsin Mediated Post-Illumination Pupil Response (PIPR).

Adhikari P, Pearson CA, Anderson AM, Zele AJ, Feigl B - Sci Rep (2015)

Bottom Line: Melanopsin containing intrinsically photosensitive Retinal Ganglion cells (ipRGCs) mediate the pupil light reflex (PLR) during light onset and at light offset (the post-illumination pupil response, PIPR).Recent evidence shows that the PLR and PIPR can provide non-invasive, objective markers of age-related retinal and optic nerve disease; however there is no consensus on the effects of healthy ageing or refractive error on the ipRGC mediated pupil function.Here we isolated melanopsin contributions to the pupil control pathway in 59 human participants with no ocular pathology across a range of ages and refractive errors.

View Article: PubMed Central - PubMed

Affiliation: Medical Retina and Visual Science Laboratories, Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Brisbane QLD 4059, Australia.

ABSTRACT
Melanopsin containing intrinsically photosensitive Retinal Ganglion cells (ipRGCs) mediate the pupil light reflex (PLR) during light onset and at light offset (the post-illumination pupil response, PIPR). Recent evidence shows that the PLR and PIPR can provide non-invasive, objective markers of age-related retinal and optic nerve disease; however there is no consensus on the effects of healthy ageing or refractive error on the ipRGC mediated pupil function. Here we isolated melanopsin contributions to the pupil control pathway in 59 human participants with no ocular pathology across a range of ages and refractive errors. We show that there is no effect of age or refractive error on ipRGC inputs to the human pupil control pathway. The stability of the ipRGC mediated pupil response across the human lifespan provides a functional correlate of their robustness observed during ageing in rodent models.

No MeSH data available.


Related in: MedlinePlus

Pupil trace showing the average (n = 59 participants; 21–70 years old) pupil light reflex (PLR) during presentation of a 10 s, 448 nm (blue) light pulse (14.5 log quanta.cm−2.s−1; 25° diameter), and the post-illumination pupil response (PIPR) after light offset.The dark blue trace shows the mean PLR and PIPR and light blue traces show the 95% confidence limits of the mean. The temporal sequence of the pupillometry protocol is indicated by the filled rectangles positioned along the abscissa. The pupil analysis metrics are noted on the trace and defined in Table 1. PRE = pre-stimulus duration; AUC = area under curve.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4664956&req=5

f2: Pupil trace showing the average (n = 59 participants; 21–70 years old) pupil light reflex (PLR) during presentation of a 10 s, 448 nm (blue) light pulse (14.5 log quanta.cm−2.s−1; 25° diameter), and the post-illumination pupil response (PIPR) after light offset.The dark blue trace shows the mean PLR and PIPR and light blue traces show the 95% confidence limits of the mean. The temporal sequence of the pupillometry protocol is indicated by the filled rectangles positioned along the abscissa. The pupil analysis metrics are noted on the trace and defined in Table 1. PRE = pre-stimulus duration; AUC = area under curve.

Mentions: The PLR during light stimulation was quantified using the transient PLR and peak pupil constriction metrics described in Table 1 and Fig. 2. The transient PLR is predominantly controlled by the outer retina, at least at long wavelengths34 and the peak pupil constriction has been shown to quantify the combination of outer and inner retinal inputs depending on stimulus wavelength4. To determine inner retinal ipRGC function, the PIPR after light offset was quantified with the four metrics (6 s, plateau, AUC early and late) (see Feigl et al.12 and Adhikari et al.7 for details of the metrics). The metrics were derived from the best-fit of the linear and exponential models to the data681132. The baseline pupil diameter (BPD) decreases with age173536 and it affects the pupil constriction amplitude (in mm) such that a smaller amplitude is observed with a smaller BPD17. To account for this effect, the pupil diameter during light stimulation and after light offset was normalised to the BPD. The peak pupil constriction and PIPR amplitudes are therefore presented in percentage of the BPD. For the peak constriction amplitude, 6 s PIPR, and plateau PIPR, a smaller percentage value indicates a larger pupil response.


Effect of Age and Refractive Error on the Melanopsin Mediated Post-Illumination Pupil Response (PIPR).

Adhikari P, Pearson CA, Anderson AM, Zele AJ, Feigl B - Sci Rep (2015)

Pupil trace showing the average (n = 59 participants; 21–70 years old) pupil light reflex (PLR) during presentation of a 10 s, 448 nm (blue) light pulse (14.5 log quanta.cm−2.s−1; 25° diameter), and the post-illumination pupil response (PIPR) after light offset.The dark blue trace shows the mean PLR and PIPR and light blue traces show the 95% confidence limits of the mean. The temporal sequence of the pupillometry protocol is indicated by the filled rectangles positioned along the abscissa. The pupil analysis metrics are noted on the trace and defined in Table 1. PRE = pre-stimulus duration; AUC = area under curve.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4664956&req=5

f2: Pupil trace showing the average (n = 59 participants; 21–70 years old) pupil light reflex (PLR) during presentation of a 10 s, 448 nm (blue) light pulse (14.5 log quanta.cm−2.s−1; 25° diameter), and the post-illumination pupil response (PIPR) after light offset.The dark blue trace shows the mean PLR and PIPR and light blue traces show the 95% confidence limits of the mean. The temporal sequence of the pupillometry protocol is indicated by the filled rectangles positioned along the abscissa. The pupil analysis metrics are noted on the trace and defined in Table 1. PRE = pre-stimulus duration; AUC = area under curve.
Mentions: The PLR during light stimulation was quantified using the transient PLR and peak pupil constriction metrics described in Table 1 and Fig. 2. The transient PLR is predominantly controlled by the outer retina, at least at long wavelengths34 and the peak pupil constriction has been shown to quantify the combination of outer and inner retinal inputs depending on stimulus wavelength4. To determine inner retinal ipRGC function, the PIPR after light offset was quantified with the four metrics (6 s, plateau, AUC early and late) (see Feigl et al.12 and Adhikari et al.7 for details of the metrics). The metrics were derived from the best-fit of the linear and exponential models to the data681132. The baseline pupil diameter (BPD) decreases with age173536 and it affects the pupil constriction amplitude (in mm) such that a smaller amplitude is observed with a smaller BPD17. To account for this effect, the pupil diameter during light stimulation and after light offset was normalised to the BPD. The peak pupil constriction and PIPR amplitudes are therefore presented in percentage of the BPD. For the peak constriction amplitude, 6 s PIPR, and plateau PIPR, a smaller percentage value indicates a larger pupil response.

Bottom Line: Melanopsin containing intrinsically photosensitive Retinal Ganglion cells (ipRGCs) mediate the pupil light reflex (PLR) during light onset and at light offset (the post-illumination pupil response, PIPR).Recent evidence shows that the PLR and PIPR can provide non-invasive, objective markers of age-related retinal and optic nerve disease; however there is no consensus on the effects of healthy ageing or refractive error on the ipRGC mediated pupil function.Here we isolated melanopsin contributions to the pupil control pathway in 59 human participants with no ocular pathology across a range of ages and refractive errors.

View Article: PubMed Central - PubMed

Affiliation: Medical Retina and Visual Science Laboratories, Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Brisbane QLD 4059, Australia.

ABSTRACT
Melanopsin containing intrinsically photosensitive Retinal Ganglion cells (ipRGCs) mediate the pupil light reflex (PLR) during light onset and at light offset (the post-illumination pupil response, PIPR). Recent evidence shows that the PLR and PIPR can provide non-invasive, objective markers of age-related retinal and optic nerve disease; however there is no consensus on the effects of healthy ageing or refractive error on the ipRGC mediated pupil function. Here we isolated melanopsin contributions to the pupil control pathway in 59 human participants with no ocular pathology across a range of ages and refractive errors. We show that there is no effect of age or refractive error on ipRGC inputs to the human pupil control pathway. The stability of the ipRGC mediated pupil response across the human lifespan provides a functional correlate of their robustness observed during ageing in rodent models.

No MeSH data available.


Related in: MedlinePlus