Untersuchungen zur Variabilität des phasischen Pupillenlichtreflexes

Abstract

Infrared pupillography was used to determine physiological time parameters of the direct phasic light reflex in 101 normal subjects. These parameters include latency, contraction and redilatation times as well as total reaction time, measured in response to 4 different light stimulus intensities. A total of more than 4000 pupillary stimulations in these subjects was analyzed statistically. The study of these time parameters included determination of the mean, the standard deviation and three dimensional analysis of variance, with the following results: 1. The physiological time parameters are bilaterally symmetrical. 2. The most stable parameters with least variability in an individual subject were latency and contraction time. The redilatation time, however, showed marked intra-individual variability. 3. Variance analysis revealed a high degree of correlation among the different parameters to light stimuli of varying intensity. 4. There was a highly significant prolongation of latency and of contraction time with increasing age. 5. No sex dependent effect on physiological time parameters was found. In addition, no interaction among light stimulus intensity, age and sex could be detected. Possible applications of the method for clinical neurological examination are discussed.

The potential of infrared pupillography in routine police traffic checks

“…In concordance with those results, the latest examined parameters also proved to be comparatively suitable for differentiating between persons being under the influence of central nervous acting substances and control persons. The results concerning the standard deviation largely correlated with the data reported by Müller-Jensen [8].…”

“…And, ever since the introduction of infrared pupillography by Matthes in 1941, this measurement method has continuously been improved, both in effectiveness and handling [1,8]. Nowadays, highly effective and portable devices are available for very precisely registering and recording the temporal sequence of changes in the pupil size during the light reflex.…”

“…Apart from the fact, that the torch test is not standardized at all, and also due to considerable interindividual variations of the pupil parameters and the pupil reaction, so far no consistent data has been published to allow a satisfactory definition of a "normal" pupil response. First physiological time values of the phasic PLR on a larger scale were presented more than 30 years ago [8], which was followed by other studies [2,3]. However, the interpretation of the results is still highly variable and mainly based on subjective experience.…”

Pupil function as an indicator of being under the influence of central nervous system-acting substances from a traffic-medicine perspective – Part II

“…Now, highly effective and portable devices are available for very precisely registering and recording the temporal sequence of changes in the size of the pupil during the light reflex. 13,14 As reported in the literature, an accurate and prompt pupil reaction does not always correlate with fitness to drive. 15 Thus, examination of pupil size and function by itself is generally not regarded as sufficient to assess roadworthiness.…”

“…Because of this and other reasons, the interpretation of the results is highly variable and mainly based on subjective experience. First physiological time values of the phasic PLR on a larger scale were presented by Mu¨ller-Jensen in 1976, 14 and this was followed by others. 6,20 Based on former published findings, 9-11 statistical analysis is presented here of new specific parameters of the PLR.…”