title: Novel mathematical algorithm for pupillometric data analysis.
abstract: Pupillometry is used clinically to evaluate retinal and optic nerve function by measuring pupillary response to light stimuli. We have developed a mathematical algorithm to automate and expedite the analysis of non-filtered, non-calculated pupillometric data obtained from mouse pupillary light reflex recordings, obtained from dynamic pupillary diameter recordings following exposure of varying light intensities. The non-filtered, non-calculated pupillometric data is filtered through a low pass finite impulse response (FIR) filter. Thresholding is used to remove data caused by eye blinking, loss of pupil tracking, and/or head movement. Twelve physiologically relevant parameters were extracted from the collected data: (1) baseline diameter, (2) minimum diameter, (3) response amplitude, (4) re-dilation amplitude, (5) percent of baseline diameter, (6) response time, (7) re-dilation time, (8) average constriction velocity, (9) average re-dilation velocity, (10) maximum constriction velocity, (11) maximum re-dilation velocity, and (12) onset latency. No significant differences were noted between parameters derived from algorithm calculated values and manually derived results (p ≥ 0.05). This mathematical algorithm will expedite endpoint data derivation and eliminate human error in the manual calculation of pupillometric parameters from non-filtered, non-calculated pupillometric values. Subsequently, these values can be used as reference metrics for characterizing the natural history of retinal disease. Furthermore, it will be instrumental in the assessment of functional visual recovery in humans and pre-clinical models of retinal degeneration and optic nerve disease following pharmacological or gene-based therapies.
authors.affiliation: Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, United States; F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Canver
authors.forename: Adam C
authors.initials: AC
authors.lastname: Canver
authors.forename: Karen E
authors.initials: KE
authors.lastname: Revere
authors.forename: Defne
authors.initials: D
authors.lastname: Amado
authors.forename: Jean
authors.initials: J
authors.lastname: Bennett
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Chung
mesh_terms: D000465:Algorithms; D001767:Blinking; D005133:Eye Movements; D019416:Head Movements; D006801:Humans; D011680:Pupil
keywords: Algorithm; Pupillometry; Retinal function