Chapter 3. Distant and Near Vision

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1873 ◽  
Vol 21 (139-147) ◽  
pp. 423-425

This paper is to show that the increase in the convexity of the lens, when accommodated for near vision, is effected by compression of the equator of the lens by an erectile cushion composed of the ciliary processes turgid with blood, the ciliary muscle being the motor agent; also that the iris aids accommodation by increasing its rapidity, but that accommodation of vision can be effected slowly without the assistance of the iris. The author states that, by dissection of human eyes, he has determined the existence of an erectile mass attached to the interior surface of the ciliary muscle from which the ciliary processes proceed, and that in dissections of injected specimens the vessels of the ciliary processes and of the erectile mass can be seen to pass through and between the fibres of the ciliary muscle near to the apex of that muscle.


Author(s):  
Anna-Lena MR Arnold ◽  
Nicolas Goujon ◽  
Lucy Busija ◽  
Sarah Fox ◽  
Jing Xie ◽  
...  

2014 ◽  
Vol 08 (01) ◽  
pp. 23 ◽  
Author(s):  
José L Güell ◽  
Omar A Barrada ◽  
◽  
◽  

Presbyopia remains the last frontier for refractive surgeons. With increased demand for spectacle independence at all ages, ophthalmologists are exploring different approaches for presbyopia correction. The idea of adding synthetic material to the cornea for the management of presbyopia has come a long way since its inception. The Raindrop® (ReVision Optics®), KAMRA™ Inlays (AcuFocus™) and the Flexivue Microlens™ (Presbia™) are three very different inlays that attempt to reverse presbyopia through different mechanisms. The Raindrop changes the curvature of the anterior cornea in the plane of the pupil, the Kamra uses the principle of the pinhole to increase depth of focus, while the Flexivue is a refractive annular add lenticule that creates a paracentral zone for near vision. The decreased incidence of complications, ease of insertion, reversibility and potential applicability to patients with various refractive statuses make inlays a powerful addition to the armamentarium in the management of presbyopia.


1949 ◽  
Vol 32 (12) ◽  
pp. 1719-1724 ◽  
Author(s):  
Kenneth N. Ogle ◽  
Wendell Triller
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2018 ◽  
Vol 28 (4) ◽  
pp. 419-424 ◽  
Author(s):  
Jorge L Alió ◽  
Ana B Plaza-Puche ◽  
Jorge L Alió del Barrio ◽  
Pedro Amat-Peral ◽  
Vicente Ortuño ◽  
...  

Purpose: To evaluate clinical and visual outcomes, quality of near vision, and intraocular optical quality of patients bilaterally implanted with a trifocal PanOptix intraocular lens. Methods: In this prospective consecutive case-series study, 52 eyes of 26 bilateral patients (mean age, 60.2 ± 7.4 years) were implanted with the AcrySof IQ Panoptix intraocular lens. Visual acuity, defocus curve, contrast sensitivity (Pelli-Robson test), near activity visual questionnaire, and internal aberrations with Osiris were evaluated. A prototype light-distortion analyzer was used to quantify the postoperative light-distortion indices. The follow-up was 6 months after surgery. Results: Uncorrected, corrected distance, and uncorrected near visual acuities improved with the surgery (p ≤ 0.02). Distance corrected near visual acuity was 0.13 ± 0.10, 0.13 ± 0.13, and 0.13 ± 0.08 at 1, 3, and 6 months after surgery, respectively (p = 0.82). Distance corrected intermediate visual acuities were 0.09 ± 0.13, 0.13 ± 0.15, and 0.12 ± 0.12 at 1, 3, and 6 months, postoperatively. Binocular contrast sensitivity was 1.86 ± 0.15 Log Units. Defocus curve provided a visual acuity equal or better to 0.30 LogMAR between defocus levels of +0.50 to −3.00 D. The near activity visual questionnaire scores improved significantly with the surgery (p < 0.01). Conclusion: The AcrySof IQ Panoptix intraocular lens is able to restore visual function with an acceptable intermediate and near vision after cataract surgery with good contrast sensitivity and an improvement in the near activity visual questionnaire.


2017 ◽  
Vol 76 (1) ◽  
Author(s):  
Ving F. Chan ◽  
Jyoti Naidoo ◽  
Farai S. Chinanayi ◽  
Kovin S. Naidoo

Background: Uncorrected near vision impairment affects the performance of near vision tasks and activities for an estimated 410 million people worldwide. Once normal vision becomes blurred or impaired, the ordinary and simple daily routines of individuals become difficult; often resulting in frustration and irritation, which is consequently reflected in their quality of life.Aim: We investigated the change of vision-related quality of life (VRQoL) following near correction among textile factory workers in South Africa.Methods: Presbyopic subjects who were 40 years and older with no other eye conditions were provided near spectacle correction. We interviewed subjects to ascertain their VRQoL scores using the National Eye Institute Visual Function Questionnaire, pre-treatment and 6 months after the provision of near corrections.Setting: The study was conducted among the textile factory workers in KwaZulu-Natal, South Africa.Results: A total of 423 textile factory workers were followed up from seven textile factories in Durban. The overall increase in VRQoL scores of 21.9 (95% CI 16.7–27) was significant (p < 0.01). This translates to a 36.5% (95% CI 30.6–42.4) change in VRQoL. The increase was highest among participants of African origin 25.1 (95% CI 21.14–29.1), males 18.8 (95% CI 12.6–27.2), among those who had completed primary school 35.8 (95% CI 21.7–49.9) and among participants with other responsibilities (ironing and quality assurance) 21.9 (95% CI 16.7–27).Conclusion: Correcting near vision impairment improved the VRQoL scores of textile factory workers. The results showed that VRQoL scores increased significantly across levels of education and categories of responsibility


2021 ◽  
Vol 37 (11) ◽  
pp. 746-753
Author(s):  
Jung Wan Kim ◽  
Youngsub Eom ◽  
Eun Gyu Yoon ◽  
Jong Suk Song ◽  
Ji Won Jeong ◽  
...  
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1997 ◽  
Author(s):  
M. Lauriola
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