Effects of dipivefrin and pilocarpine on pupil diameter, automated perimetry and LogMAR acuity

1999 ◽  
Vol 237 (2) ◽  
pp. 117-124 ◽  
Author(s):  
D. F. Edgar ◽  
David P. Crabb ◽  
Alicja R. Rudnicka ◽  
John G. Lawrenson ◽  
Nancy M. Guttridge ◽  
...  
Keyword(s):  
Pupil Diameter ◽  
Automated Perimetry ◽  
Logmar Acuity

Evaluating Responses of Circulatory Systems, Sweating and Pupil Diameter to Postural Change

2018 ◽  
Vol 138 (9) ◽  
pp. 1141-1147
Author(s):  
Munemichi Tateyama ◽  
Ikuhide Kinoshita ◽  
Akihiko Akao ◽  
Sho Shirasaka ◽  
Takashi Numata ◽  
...  
Keyword(s):  
Pupil Diameter ◽  
Postural Change

scholarly journals Experimental Analysis of Driver Visual Characteristics in Urban Tunnels

2021 ◽  
Vol 11 (9) ◽  
pp. 4274
Author(s):  
Song Fang ◽  
Jianxiao Ma
Keyword(s):  
Traffic Safety ◽  
Clustering Algorithm ◽  
Pupil Diameter ◽  
Data Fitting ◽  
Eye Tracker ◽  
Tunnel Length ◽  
Point Distribution ◽  
Change Rate ◽  
Visual Characteristics ◽  
Diameter Change

Through an urban tunnel-driving experiment, this paper studies the changing trend of drivers’ visual characteristics in tunnels. A Tobii Pro Glasses 2 wearable eye tracker was used to measure pupil diameter, scanning time, and fixation point distribution of the driver during driving. A two-step clustering algorithm and the data-fitting method were used to analyze the experimental data. The results show that the univariate clustering analysis of the pupil diameter change rate of drivers has poor discrimination because the pupil diameter change rate of drivers in the process of “dark adaptation” is larger, while the pupil diameter change rate of drivers in the process of “bright adaptation” is relatively smooth. The univariate and bivariate clustering results of drivers’ pupil diameters were all placed into three categories, with reasonable distribution and suitable differentiation. The clustering results accurately corresponded to different locations of the tunnel. The clustering method proposed in this paper can identify similar behaviors of drivers at different locations in the transition section at the tunnel entrance, the inner section, and the outer area of the tunnel. Through data-fitting of drivers’ visual characteristic parameters in different tunnels, it was found that a short tunnel, with a length of less than 1 km, has little influence on visual characteristics when the maximum pupil diameter is small, and the percentage of saccades is relatively low. An urban tunnel with a length between 1 and 2 km has a significant influence on visual characteristics. In this range, with the increase in tunnel length, the maximum pupil diameter increases significantly, and the percentage of saccades increases rapidly. When the tunnel length exceeds 2 km, the maximum pupil diameter does not continue to increase. The longer the urban tunnel, the more discrete the distribution of drivers’ gaze points. The research results should provide a scientific basis for the design of urban tunnel traffic safety facilities and traffic organization.

scholarly journals Cerebral trauma-induced dyschromatopsia in the left hemifield: case presentation

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yoko Mase ◽  
Yoshitsugu Matsui ◽  
Eriko Uchiyama ◽  
Hisashi Matsubara ◽  
Masahiko Sugimoto ◽  
...  
Keyword(s):  
Visual Field ◽  
Color Vision ◽  
Temporal Lobe ◽  
Fusiform Gyrus ◽  
Ganglion Cell Complex ◽  
Automated Perimetry ◽  
Subjective Symptoms ◽  
Anterior Temporal Lobe ◽  
Case Presentation ◽  
Cerebral Trauma

Abstract Background Acquired color anomalies caused by cerebral trauma are classified as either achromatopsias or dyschromatopsias (Zeki, Brain 113:1721–1777, 1990). The three main brain regions stimulated by color are V1, the lingual gyrus, which was designated as human V4 (hV4), and the fusiform gyrus, designated as V4α. (Zeki, Brain 113:1721–1777, 1990). An acquired cerebral color anomaly is often accompanied by visual field loss (hemi- and quadrantanopia), facial agnosia, prosopagnosia, visual agnosia, and anosognosia depending on the underlying pathology (Bartels and Zeki, Eur J Neurosci 12:172–193, 2000), (Meadows, Brain 97:615–632, 1974), (Pearman et al., Ann Neurol 5:253–261, 1979). The purpose of this study was to determine the characteristics of a patient who developed dyschromatopsia following a traumatic injury to her brain. Case presentation The patient was a 24-year-old woman who had a contusion to her right anterior temporal lobe. After the injury, she noticed color distortion and that blue objects appeared green in the left half of the visual field. Although conventional color vision tests did not detect any color vision abnormalities, short wavelength automated perimetry (SWAP) showed a decrease in sensitivity consistent with a left hemi-dyschromatopsia. Magnetic resonance imaging (MRI) detected abnormalities in the right fusiform gyrus, a part of the anterior temporal lobe. At follow-up 14 months later, subjective symptoms had disappeared, but the SWAP abnormalities persisted and a thinning of the sectorial ganglion cell complex (GCC) was detected. Conclusion The results indicate that although the subjective symptoms resolved early, a reduced sensitivity of SWAP remained and the optical coherence tomography (OCT) showed GCC thinning. We conclude that local abnormalities in the anterior section of fusiform gyrus can cause mild cerebral dyschromatopsia without other symptoms. These findings indicate that it is important to listen to the symptoms of the patient and perform appropriate tests including the SWAP and OCT at the early stage to objectively prove the presence of acquired cerebral color anomaly.

Changes in pupillometry associated with dissipated energy during phacoemulsification

2020 ◽  
pp. 112067212098437
Author(s):  
Giulia Coco ◽  
Pierluca Cremonesi ◽  
Nardine Menassa ◽  
Luca Pagano ◽  
Kunal A Gadhvi ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Generalized Linear Model ◽  
Pupil Diameter ◽  
University Hospital ◽  
Dissipated Energy ◽  
Dynamic Measurements ◽  
Operative Complications ◽  
Cumulative Dissipated Energy ◽  
Chamber Measurements ◽  
Phacoemulsification Cataract Surgery

Purpose: To investigate the effect of ultrasound level during phacoemulsification on pupil dynamics. Methods: Comparative retrospective study on patients who underwent routine cataract surgery at the Royal Liverpool University Hospital. Clinical parameters, anterior chamber measurements, axial length, surgeon grade, time of surgery, level of ultrasound used (cumulative dissipated energy, CDE), intra- and post-operative complications were collected. Pupil diameters were collected before and 4 ± 1 weeks after surgery in static scotopic, mesopic, photopic pupil conditions. Also, pupil dynamic measurements after luminous stimulus were recorded. Changes in static pupil diameters, relative dilation at 3.5 s after luminous stimulus, and time to reach 75% and 95% of maximum dilation were measured. Results: Forty-eight eyes of 24 patients (13 males) were included with a mean age of 73.1 ± 14.6 years. Mean CDE value was 18.11 ± 10.56. Mean scotopic pupil diameters decreased by 0.24 ± 0.48 mm ( p = 0.021) in the operated eye. Significant correlation was found between reduction in scotopic pupil diameter and CDE ( p = 0.05). A generalized linear model confirmed that the level of CDE was significantly associated with reduction in scotopic pupil diameter ( p = 0.026). Patients who underwent surgeries with lower CDE (0 < CDE ⩽ 10 and 10 < CDE ⩽ 20) did not experience significant changes in scotopic pupil diameter after surgery ( p = 0.28 and p = 0.79, respectively) as opposed to those with higher CDE (CDE > 20; p = 0.03). Conclusion: Phacoemulsification cataract surgery and the cumulative dissipated energy may be associated with changes in pupil behaviour.

The Control of the Eye's Intrinsic Muscles: A Multivariable Optimum Performance Control System

1968 ◽  
Vol 1 (8) ◽  
pp. T.129-T.132 ◽  
Author(s):  
F. M. Toates
Keyword(s):  
Control System ◽  
Control Systems ◽  
Pupil Diameter ◽  
Control Model ◽  
Point Of View ◽  
Theoretical Point ◽  
Pupil Control ◽  
Performance Control ◽  
A Value ◽  
Intrinsic Muscles

The reciprocal interaction between the accommodation and pupil control systems of the human eye is examined from a theoretical point of view. The system, which is responsible for maintaining pupil diameter at a value which is a compromise between conflicting requirements, is represented by a control model, and is considered in terms of the concept of a performance index.

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