RESUMO
Pupil light reflex can be used as a non-invasive ocular predictor of cephalic autonomic nervous system integrity. Spectral sensitivity of the pupil's response to light has, for some time, been an interesting issue. It has generally, however, only been investigated with the use of white light and studies with monochromatic wavelengths are scarce. This study investigates the effects of wavelength and age within three parameters of the pupil light reflex (amplitude of response, latency, and velocity of constriction) in a large sample of younger and older adults (N = 97), in mesopic conditions. Subjects were exposed to a single light stimulus at four different wavelengths: white (5600°K), blue (450 nm), green (510 nm), and red (600 nm). Data was analyzed appropriately, and, when applicable, using the General Linear Model (GLM), Randomized Complete Block Design (RCBD), Student's t-test and/or ANCOVA. Across all subjects, pupillary response to light had the greatest amplitude and shortest latency in white and green light conditions. In regards to age, older subjects (46-78 years) showed an increased latency in white light and decreased velocity of constriction in green light compared to younger subjects (18-45 years old). This study provides data patterns on parameters of wavelength-dependent pupil reflexes to light in adults and it contributes to the large body of pupillometric research. It is hoped that this study will add to the overall evaluation of cephalic autonomic nervous system integrity.
RESUMO
Pupillometry is becoming a relevant tool in Vision Sciences. So far, only a few studies have explored the relationship between pupil reflex measures and drug consumption. The aim of this study was to assess the applicability of dynamic mesopic pupillometry as an objective measurement method for the detection of blood alcohol levels above the legal limit. In a quasiexperimental design, 19 volunteers were asked to participate in two conditions (before and after alcohol intake). In session with alcohol intake, participants were asked to consume 27.5 ml of alcohol in 60 minute intervals for four hours. Pupillometry records were conducted by means of the Power Refractor II, using four types of light stimulation: white (5600 K), blue (450 nm), green (510 nm) and red (600 nm). The basal diameter of the pupil increased significantly for alcohol concentrations equal to or greater than 0.25 mg/l in exhaled breath. Moreover, the value of the amplitude for red light constriction also provided significant differences between the two conditions. These results are promising in the search for new methods to detect illegal alcohol levels among drivers. This study demonstrates that basal pupil diameter increase and amplitude response could be used as an alcohol consumption level indicator. However, further studies are necessary to validate this and other diagnose methods complementary to breathalyzer and other drugs tests.
Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Condução de Veículo , Pupila/efeitos dos fármacos , Pupila/fisiologia , Adulto , Técnicas e Procedimentos Diagnósticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
La pupilometría se ha convertido en una herramienta de gran interés en las Ciencias de la Visión. Hasta el momento, solo unos pocos estudios han explorado la relación entre el reflejo pupilar y el consumo de drogas. El objetivo de este estudio fue evaluar la aplicabilidad de la pupilometría dinámica mesópica como método objetivo para la detección de niveles de alcoholemia por encima del límite legal. Se utilizó un diseño de carácter cuasi-experimental, con 19 voluntarios participando en dos condiciones (pre y post ingesta de alcohol). En la sesión con alcohol, los participantes consumieron 27.5 ml de alcohol en intervalos de 60 minutos durante 4 horas. Se llevaron a cabo registros de pupilometría mediante el Power Refractor II, utilizándose cuatro tipos de estimulación lumínica: blanca (5600 K), azul (450 nm), verde (510 nm) y roja (600 nm). El diámetro basal aumentó significativamente a partir de concentraciones de alcohol en aire espirado iguales o mayores de 0.25 mg/l. Además, el valor de la amplitud de constricción para la luz roja también ofreció diferencias significativas entre las dos condiciones. Estos resultados resultan prometedores en la búsqueda de nuevos métodos de detección de niveles de alcoholemia no permitidos al volante. En este estudio se demuestra que el incremento del diámetro basal y la amplitud pupilar pueden ser utilizados como indicador del nivel de consumo de alcohol. Son necesarios más estudios para validar éste y otros métodos de diagnóstico complementarios a las actuales pruebas de alcoholemia y de consumo de sustancias psicotropas (AU)
Pupillometry is becoming a relevant tool in Vision Sciences. So far, only a few studies have explored the relationship between pupil reflex measures and drug consumption. The aim of this study was to assess the applicability of dynamic mesopic pupillometry as an objective measurement method for the detection of blood alcohol levels above the legal limit. In a quasiexperimental design, 19 volunteers were asked to participate in two conditions (before and after alcohol intake). In session with alcohol intake, participants were asked to consume 27.5 ml of alcohol in 60 minute intervals for four hours. Pupillometry records were conducted by means of the Power Refractor II, using four types of light stimulation: white (5600 K), blue (450 nm), green (510 nm) and red (600 nm). The basal diameter of the pupil increased significantly for alcohol concentrations equal to or greater than 0.25 mg/l in exhaled breath. Moreover, the value of the amplitude for red light constriction also provided significant differences between the two conditions. These results are promising in the search for new methods to detect illegal alcohol levels among drivers. This study demonstrates that basal pupil diameter increase and amplitude response could be used as an alcohol consumption level indicator. However, further studies are necessary to validate this and other diagnose methods complementary to breathalyzer and other drugs tests (AU)
