The ChromaGen contact lens system: colour vision test results and subjective responses

Objectives. To describe the past 20 years’ correction modalities for keratoconus and their visual outcomes and possible complications.Methods. A review of the published literature related to the visual outcomes and possible complications in the context of keratoconus management using nonsurgical procedures for the last 20 years (glasses and contact lenses) was performed. Original articles that reported the outcome of any correction modalities of keratoconus management were reviewed.Results. The most nonsurgical procedure used on keratoconus management is the contact lens fitting. Soft contact lenses and soft toric contact lenses, rigid gas-permeable contact lenses, piggyback contact lens system, hybrid contact lenses, and scleral and corneoscleral contact lenses form the contemporary range of available lens types for keratoconus management with contact lenses. All of them try to restore the vision, improve the quality of life, and delay surgical procedures in patients with this disease. Complications are derived from the intolerance of using contact lens, and the use of each depends on keratoconus severity.Conclusions. In the context of nonsurgical procedures, the use of contact lenses for the management of keratoconic patients represents a good alternative to restore vision and improve the quality of live in this population.

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DRY EYE STATUS BASED ON THE SCHIRMER TEST AND TEAR FILM BREAK UP TIME RESULTS FOLLOWING USE OF SOFT CONTACT LENS IN KERALA

International Journal of Medical and Biomedical Studies ◽

10.32553/ijmbs.v3i10.660 ◽

2019 ◽

Vol 3 (10) ◽

Author(s):

Dr. Simon George

Keyword(s):

Dry Eye ◽

Contact Lens ◽

Tear Film ◽

Test Results ◽

Schirmer Test ◽

Soft Contact ◽

Soft Contact Lens ◽

Break Up

Prospective two years study of the dry eye status following use of soft contact lens. Based on the Schirmer test results, 10 % soft contact lens wearers developed mild dry eye at the end of 1 year and 15 % developed mild dry eye at the end of 2 years. No patient had moderate or severe dry eye. Based on the Tear film break up time results, 17 % soft contact lens wearers developed mild dry eye at the end of 1 year and 30 % developed mild dry eye at the end of 2 years. 1% had moderate dry eye at the end of 2 years. No patient had severe dry eye. Keywords: Schirmer test, Tear film break up time, soft contact lens, dry eye

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The Bio-Tribological Effect of Poly-Gamma-Glutamic Acid in the Lysozyme-Ionic Contact Lens System

Polymers ◽

10.3390/polym12010156 ◽

2020 ◽

Vol 12 (1) ◽

pp. 156

Author(s):

Chen-Ying Su ◽

Lung-Kun Yeh ◽

Chi-Chun Lai ◽

Mihaela Dubuisson ◽

Yi-Fei Tsao ◽

...

Keyword(s):

Friction Coefficient ◽

Glutamic Acid ◽

Contact Lens ◽

Contact Lenses ◽

Lens System ◽

Friction Testing ◽

Lubricating Property ◽

Velocity Variations

Feeling comfortable is an important issue for contact lens wearers as contact lenses are worn for an extensive period of time. It has been shown that the in vitro friction coefficient of contact lenses is correlated to the degree of in vivo comfort, thus many studies focus on establishing friction testing methods for investigating the friction coefficient of contact lenses or contact lens care solution. We have previously demonstrated the lubricating property of poly-gamma-glutamic acid (γ-PGA)-containing care solution, and it could reduce the high friction coefficient caused by lysozyme. However, the mechanism of how γ-PGA-containing care solution reduces the lysozyme-induced friction coefficient of contact lenses is unclear. We investigated the bio-tribological effect of γ-PGA on ionic contact lenses in the presence of lysozyme by testing load and velocity variations. The ability to remove lysozyme deposition by γ-PGA and viscosity analysis of γ-PGA-containing care solutions were also investigated to understand the potential mechanism. Our results showed that the friction coefficient of γ-PGA-containing care solution with lysozyme was the lowest in both load and velocity variations, and γ-PGA functions distinctly in the lysozyme-ionic contact lens system. We proposed a model of how γ-PGA could reduce the friction coefficient in these two conditions.

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Experience Using the Heidelberg Retina Angiograph 2 with a Wide-Field Contact Lens System in Diabetic Retinopathy Cases

The Open Ophthalmology Journal ◽

10.2174/1874364101307010054 ◽

2013 ◽

Vol 7 (1) ◽

pp. 54-57 ◽

Cited By ~ 1

Author(s):

Miyo Shiibashi ◽

Miwako Yoshimoto ◽

Takashi Shigeeda ◽

Shigehiko Kitano ◽

Satoshi Kato

Keyword(s):

Diabetic Retinopathy ◽

Contact Lens ◽

Laser System ◽

Corneal Dystrophy ◽

Wide Field ◽

Lens System ◽

Advantages And Disadvantages ◽

Confocal Scanning ◽

Confocal Scanning Laser ◽

Media Opacities

Introduction: HRA (Heiderberg Retina Angiograph) 2 uses a confocal scanning laser system which can provide high quality digital images but its imaging field is only 30°at most. HRA2 with a wide-field contact lens system allows an imaging field of up to 150°. Methods: We examined the advantages and disadvantages of HRA2, with a wide-field contact lens, for the evaluating diabetic retinopathy (DR). Results: HRA2 was beneficial for obtaining images of the entire retina simultaneously, without missing peripheral retinal non-perfusion and neovascularization. On the other hand, clear images connot be acquired in cases with media opacities such as corneal dystrophy, cataract and asteroid hyalosis, or in those with yellow tinted IOL. Conclusions: HRA2 with a wide-field contact lens is useful for visualizing peripheral retinal lesions in DR cases.

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Management of Post-LASiK Keratoectasia with a Piggyback Contact Lens System

Canadian Journal of Optometry ◽

10.15353/cjo.77.514 ◽

2015 ◽

Vol 77 (1) ◽

pp. 7

Author(s):

Lacey Haines ◽

Luigina Sorbara

Keyword(s):

Contact Lens ◽

Ocular Surface ◽

Contact Lenses ◽

Single Case ◽

Treatment Options ◽

Ocular Surface Disease ◽

Screening Methods ◽

Lens System ◽

Intrastromal Corneal Ring ◽

Current Screening

This case report highlights the clinical challenges involved in managing a patient with post-LASiK keratoectasia. A single case is presented with a focus on contact lens fitting and concurrent ocular surface disease. A review of the literature indicates that current screening methods prior to refractive surgery have made improvements for detecting patients at higher risk of serious complications. Possible treatment options for iatrogenic keratoconus include contact lenses, intrastromal corneal ring segments, corneal cross linking, and keratoplasty. This report demonstrates that post-LASiK keratoectasia with concurrent ocular surface disease can be successfully managed with a piggyback contact lens system.

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