Pupil Light Reflex in Parkinson's Disease: Evaluation With Pupillometry

Abstract

We evaluated pupil light reflex (PLR) in patients with Parkinson's disease (PD) and normal controls by means of pupillometry and explored its possible relation to clinical characteristics in parkinsonian patients. PLR was evaluated using pupillometry in 66 patients with PD without clinical evidence of autonomic dysfunction and 44 healthy matched controls. PLR was elicited by single flash stimuli of 24.6 candelas/m(2) intensity and 20 ms duration, and six parameters were studied after full recording of pupil's movement. A significant increase in latency (T1) and significant decrease in amplitude (R1-R2), maximum constriction velocity (V(max)), as well as maximum acceleration (AC(max)) was found in parkinsonian patients. There was no significant difference in initial radius (R1) and minimum radius (R2) values. Of the parameters studied, AC(max) emerged as a significant predictor for discrimination between PD patients and controls. There was no significant correlation between pupillometry parameters and clinical characteristic of patients (disease duration, stage, and the Unified Parkinson's Disease Rating motor scale). The study demonstrates PLR disorder in PD patients even without overt clinical autonomic dysfunction. Pupillometry appears to be a useful and noninvasive method for exploration of PLR alterations in PD and may prove to be useful for the early detection of subclinical autonomic nervous system dysfunction.

Pupillometry and123I-DaTSCAN imaging in Parkinson's Disease: A Comparison Study

“…The significant decrease in these parameters indicates parasympathetic dysfunction in PD patients. These results are in agreement with our previous study in which we examined PLR in 66 PD patients [17]. In this study, discriminant analysis showed that ACmax was the most sensitive variable in order to discriminate PD patients and controls and the most suitable for the evaluation of parasympathetic function.…”

“…Stimulus duration was 20 ms and the luminance 24.6 candelas/m 2 . The SLE flash was placed in front of the eye at a distance of 30 cm [17].…”

A wearable infrared video pupillography with multi-stimulation of consistent illumination for binocular pupil response

“…The previous studies explored that pupillary abnormalities may be occurred with diabetes, glaucoma, high myopia, demyelinating disease, autonomic neuropathy, Parkinson's disease, Alzheimer's disease, and so on [3][4][5][6][7][8][9]. The pupil reaction is affected by afferent and efferent function.…”

Infrared Video Pupillography Coupled with Smart Phone LED for Measurement of Pupillary Light Reflex

“…Currently smart phones are used to assess color vision, astigmatism, pupil size, macula integrity by the Amsler grid test, and fundus photography (Busis, 2010; Bastawrous, 2012; Bastawrous et al, 2012). Hence, an IR videography set-up coupled with a smart phone application seems an accessible approach in the assessment of the PLR in the clinical setting (Fotiou et al, 2000; Busis, 2010; Giza et al, 2011; Mohan et al, 2013). Such quantitative method is also more informative than the conventional technique using a pen torch, as the information could be used for future analysis and comparison.…”