Abstract: The most prominent causes of loss of vision in individuals over 50 years include age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy (DR). While it is important to screen for these diseases effectively, current eye care is not properly doing so for much of the population, resulting in unfortunate visual disability and high costs for patients. Innovative functional testing can be unified with other screening methods for a more robust and safer screening and prediction of disease. The goal in the creation of functional testing modalities is to develop highly sensitive screening tests that are easy to use, accessible to all users, and inexpensive. The tests herein are deployed on an iPad with easily understood and intuitive instructions for rapid, streamlined, and automatic administration. These testing modalities could become highly sensitive screenings for early detection of potentially blinding diseases. The applications from our collaborators at AMA Optics include a cone photostress recovery test for detection of AMD and diabetic macular edema (DME), brightness balance perception for optic nerve dysfunction and especially glaucoma, color vision testing which is a broad screening tool, and visual acuity test. Machine learning with the combined structural and functional data will optimize identification of disease and prediction of outcomes. Here, we review and assess various tests of visual function that are easily administered on a tablet for screening in primary care. These user-friendly and simple screening tests allow patients to be identified in the early stages of disease for referral to specialists, proper assessment and treatment.
Abstract: Pediatric glaucoma is a potentially sight-threatening disease and is considered the second leading cause of treatable childhood blindness. Pediatric glaucoma is a clinical entity including a wide range of conditions: primary congenital glaucoma, glaucoma secondary to ocular (e.g., aniridia, Peter’s anomaly), or systemic disease (e.g., Sturge Weber) and glaucoma secondary to acquired condition (pseudophakic, traumatic, uveitic glaucoma). The treatment algorithm of childhood glaucoma is a step-by-step approach, often starting with surgery, as in primary congenital glaucoma cases. Medical therapy is also crucial in the management of pediatric glaucoma. Here we reported the results of the randomized, controlled, clinical trials carried out in children treated with topical anti-glaucoma drugs. It is worth knowing that prostaglandin analogues showed an excellent systemic safety profile, while serious systemic events have been reported in children taking topical beta-blockers. Angle surgery is the first surgical option in patients diagnosed with primary congenital glaucoma, with ab interno and ab externo approaches showing similar outcomes. Trabeculectomy in children can be troublesome, as mitomycin C (MMC) can lead to bleb complications and a higher endophthalmitis rate than in adults. Glaucoma drainage devices (GDD) are no longer a last resort and can be considered a suitable option for the management of uncontrolled pediatric glaucoma after angle surgery failure.
Perception is the ability to see, hear, or become aware of external stimuli through the senses. Visual stimuli are electromagnetic waves that interact with the eye and elicit a sensation. Sensations, indeed, imply the detection, resolution, and recognition of objects and images, and their accuracy depends on the integrity of the visual system. In clinical practice, evaluating the integrity of the visual system relies greatly on the assessment of visual acuity, that is to say on the capacity to identify a signal. Visual acuity, indeed, is of utmost importance for diagnosing and monitoring ophthalmological diseases. Visual acuity is a function that detects the presence of a stimulation (a signal) and resolves its detail(s). This is the case of a symbol like “E”: the stimulus is detected, then it is resolved as three horizontal bars and a vertical bar. In fact, within the clinical setting visual acuity is usually measured with alphanumeric symbols and is a three-step process that involves not only detection and resolution, but, due to the semantic content of letters and numbers, their recognition. Along with subjective (psychophysical) procedures, objective methods that do not require the active participation of the observer have been proposed to estimate visual acuity in non-collaborating subjects, malingerers, or toddlers. This paper aims to explain the psychophysical rationale underlying the measurement of visual acuity and revise the most common procedures used for its assessment.
Background: Dyop® is a dynamic optotype with a rotating and segmented visual stimulus. It can be used for visual acuity and refractive error measurement. The objective of the study was to compare refractive errormeasurement using the Dyop® acuity and LogMAR E charts.
Methods: Fifty subjects aged 18 or above with aided visual acuity better than 6/12 were recruited. Refractive error was measured by subjective refraction methods using the Dyop® acuity chart and LogMAR E charts and the duration of measurement compared. Thibo’s notation was used to represent the refractive error obtained for analysis.
Results: There was no significant difference in terms of spherical equivalent (M) (P=0.96) or J0 (P=0.78) and J45 (P=0.51) components measured using the Dyop® acuity and LogMAR E charts. However, subjective refraction measurement was significantly faster using the Dyop® acuity chart (t=4.46, P<0.05), with an average measurement time of 419.90±91.17 versus 452.04±74.71 seconds using the LogMAR E chart.
Conclusions: Accuracy of refractive error measurement using a Dyop® chart was comparable with use of a LogMAR E chart. The dynamic optotype Dyop® could be considered as an alternative fixation target to be used in subjective refraction.
