13 documents found, page 1 of 2
Wavefront sensing: A breakthrough for objective evaluation of dynamic accommoda...
Gomes, Jessica; Franco, SandraThe purpose of this study was to use wavefront sensing as an objective method to detect and assess dynamic accommodation in subjects with accommodative dysfunctions and symptoms related to near-vision tasks. Sixty-three subjects were divided into control (N = 18), symptomatic without any accommodative dysfunction (SWD) (N = 18), infacility of accommodation (INFA) (N = 6), excess of accommodation (EA) (N = 9), a...
Prevalence of near-vision-related symptoms in a university population
Gomes, Jessica; Franco, SandraThe university population has high visual demands. It is therefore important to assess the prevalence of symptoms in these subjects, which may affect their academic performance. In this cross-sectional study, a randomized sample of 252 subjects from a university answered the Convergence Insufficiency Symptom Survey (CISS) questionnaire. In addition, questions were asked about blurred vision during and after nea...
High-order aberrations: A key factor in accommodative dysfunctions
Gomes, Jessica; Franco, SandraThis study investigated the relationship between high-order aberrations (HOAs) and accommodative dysfunctions by analyzing their changes with accommodation. Understanding this relationship is important for understanding the mechanisms underlying these conditions. Sixtythree subjects were divided into five groups: control, infacility of accommodation (INFA), excess of accommodation (EA), insufficiency of accommo...
Real-time wavefront aberrometry in subjects with accommodative excess
Gomes, Jessica; Sapkota, Kishor; Franco, SandraThe purpose of this study was to use real-time wavefront aberrometry to detect accommodative excess (AE) and to analyse the optical quality of the eye in subjects with this dysfunction. AE was detected from the accommodative response obtained by real-time wavefront aberrometry. These subjects had a significant accommodative lead to all stimuli and had difficulty relaxing accommodation. The root mean square (RMS...
Central and peripheral ocular high-order aberrations and their relationship wit...
Gomes, Jessica; Sapkota, Kishor; Franco, SandraHigh-order aberrations (HOAs) are optical defects that degrade the image quality. They change with factors such as pupil diameter, age, and accommodation. The changes in optical aberrations during accommodation are mainly due to lens shape and position changes. Primary spherical aberration (Z(4.0)) is closely related to accommodation and some studies suggested that it plays an important role in the control of a...
Spherical aberration and accommodative insufficiency: Is there a Link?
Gomes, Jessica; Sapkota, Kishor; Franco, SandraGiven the relationship between spherical aberrations and accommodation, the study of these aberrations can be helpful to understand accommodative response in subjects with accommodative dysfunctions. The purpose of this study was to evaluate on-axis and off-axis changes of primary and secondary spherical aberrations, Z(4,0) and Z(6,0), with accommodation in subjects with accommodative insufficiency (AI). Ten su...
Effect of accommodation on coma at central and peripheral retina
Sapkota, Kishor; Gomes, Jessica; Franco, SandraComa is one of the most common ocular higher order aberrations and highly affects the quality of image. It is assumed that corneal aberrations are balanced by internal (lenticular) aberrations so that retinal image quality may not have great impact. However, during accommodation, the shape, position, and curvature of the crystalline lens changes which might disrupt this balance between internal and corneal aber...
Effect of accommodation on peripheral higher order aberrations
Sapkota, Kishor; Gomes, Jessica; Franco, SandraKnowledge of the effect of accommodation on image quality of peripheral retina is crucial for better understanding of the visual system, but only a few studies have been carried out in this area. This study was designed to evaluate the effect of accommodation on higher order aberrations from third to sixth Zernike polynomials in central and peripheral retina up to 23° off-axis. We used a Hartmann–Shack aberrome...
Assessment of central and peripheral accommodative lag by aberrometry
Sapkota, Kishor; Gomes, Jessica; Franco, SandraAccommodation lag is important factor for normal vision. Higher lag of accommodation may cause various ocular symptoms particularly during near tasks. In this study, the lag of accommodation was assessed in the peripheral retina and it was compared with the central accommodative lag with aberrometer. In this cross-sectional study, fifty-three young subjects with normal visual acuity and without any active ocula...
Crystalline lens imaging during accommodation with a slit-scanning tomography s...
Gomes, Jessica; Franco, SandraA slit-scanning tomography system previously developed in the Centre of Physics of University of Minho allows to capture images of the eye and posteriorly calculus of the biometric (thickness and curvature) and optical (wavefront aberrations) properties of the corneal and crystalline lens surfaces. It is intended to optimise the system for an accurate computing of these properties of the crystalline lens in the...