Conjunctival Vascular Adaptation Related to Ocular Comfort in Habitual Contact Lens Wearers

AIM: To evaluate and compare the clinical performance of 5 kinds of polyhexamethylene biguanide (PHMB) based multi-purpose solutions (MPS) manufactured in China when used with a commercially available silicone hydrogel contact lens in terms of solution-induced corneal staining (SICS), ocular response (corneal staining and ocular hyperemia), corneal infiltrative event (CIEs) and ocular comfort. METHODS: This was a prospective, open label, randomized, parallel group clinical trial. Totally 162 participants (Pxs) who were at least 18y were enrolled and randomized into 5 groups of PHMB-based MPS made in China: Complete® MPS, Hydron® Aqua-shining moist, Baoshining™, Weicon® Fresh, Weicon® 2000 MPS (abbreviated as C, H, B, W, and W2). All participants wore balafilcon A contact lenses with monthly disposal (Bausch & Lomb Purevision®) in conjunction with the designated MPS on a daily wear for 3mo. Clinical visits were at baseline, 2wk, 1mo and 3mo. SICS and CIE were reported as first event incidence per 100 Px-months. Ocular response was graded on 0-4 scale in 0.5 steps (0=none, 4=severe) and ocular comfort was assessed via a numeric rating scale (1-10 in 1-point steps, 1=poor, 10=excellent). Ocular comfort and ocular response variables were analysed using linear mixed model. CIE and SICS were analysed using Fisher’s exact test and logistic regression. RESULTS: There were 36 (22%) Pxs who dropped out. SICS incidence for each MPS were: H (26.3%), B (20.8%), W (19.4%), W2 (13.4%), C (12.8%). The SICS rate of H was significantly different to W2 (P=0.012) and C (P=0.005). There were no significant differences in ocular response, CIE incidence and ocular comfort between different MPSs (P>0.05). Pxs with SICS had significantly lower comfort during the day and at the end of than those who did not have SICS. CONCLUSION: Differences in SICS incidence are found between MPSs but not for CIE incidence, ocular response or ocular comfort. SICS in PHMB-based MPS is found to be associated with ocular discomfort. More MPS/lens combinations should be studied in the future.

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Estimating a Just-Noticeable Difference for Ocular Comfort in Contact Lens Wearers

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.10-7051 ◽

2011 ◽

Vol 52 (7) ◽

pp. 4390 ◽

Cited By ~ 32

Author(s):

Eric B. Papas ◽

Lisa Keay ◽

Blanka Golebiowski

Keyword(s):

Contact Lens ◽

Just Noticeable Difference ◽

Ocular Comfort

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Study of Myopia Correction Using Nanoporous Polymer Gas Permeable Contact Lenses

Materiale Plastice ◽

10.37358/mp.21.4.5531 ◽

2022 ◽

Vol 58 (4) ◽

pp. 55-64

Author(s):

Silvia Salavastru ◽

Irina Andreea Niagu ◽

Luana Andrei Macovei ◽

Lucretia Anghel ◽

Nicolae Sarbu ◽

...

Keyword(s):

Contact Lens ◽

Contact Lenses ◽

Anterior Segment ◽

Silicone Hydrogel ◽

Before And After ◽

Materials Used ◽

Ocular Comfort ◽

Myopic Astigmatism ◽

Lens Wear

Ophthalmic treatments using contact lenses are now used by more and more specialists around the world. Improving contact lens (CL) materials is a condition that is constantly evolving. Contact lens materials are usually composed of polymer hydrogel or silicone hydrogel. The materials used for night contact lenses are gas permeable and they gradual flatten the center of the cornea which decreases the progression of myopia or myopic astigmatism. The aim of this study is to identify, in correlation with the chemical interactions between structural components of contact lenses and their biocompatibility with the surface layer and microtopography of the cornea or sclera, different incidents that occur in patients who have used rigid gas permeable contact lenses. The study was performed on a group of 10 patients who had a follow-up period between 4 and 6 years, who presented regularly for eye examinations. The following clinical parameters were analyzed: ocular refraction before and after wearing night contact lenses, types of contact lens materials, appearance of corneal topography, biomicroscopic examination of the anterior segment of the eye, keratometry, ocular comfort, as well as other incidents regarding this type of lenses. Difficulties caused by wearing contact lenses at night arose due to poor hygiene and maintenance in two cases or due to interruption of lens wear in one case.

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