The purpose of this study was to confirm that two distinct clinical presentations of contact lens-induced papillary conjunctivitis (CLPC), local and general, occur in hydrogel lens wear.
Retrospective analyses of 124 CLPC events were identified. The classification of CLPC was based on location and extent of papillae. CLPC was classified as local if papillae were present in one to two areas of the tarsal conjunctiva and general if papillae occurred in three or more areas. The CLPC events were compared with an asymptomatic control group in prospective clinical trials conducted from 1993 until 2003 at two clinical sites, Australia and India. Two hundred sixteen subjects from Australia and 914 subjects from India wore either high Dk silicone hydrogel or low Dk hydrogel lenses on a 6-night (6N) or 30-night extended-wear (EW) schedule. The physiological responses of the ocular surface, including tarsal conjunctiva redness and roughness, number of papillae present, lens fit and performance, and subjective patient symptoms, were measured during each visit at each site. These variables listed were compared between local CLPC groups and asymptomatic controls and general CLPC groups and asymptomatic controls.
Two types of CLPC in hydrogel lens wearers have been confirmed. Of the 124 CLPC events, there were 61 local and 63 general events. Local and general CLPC cases reported significantly greater frequency of symptoms compared with the asymptomatic controls, in particular itching, lens awareness, secretion, and blurred vision (p < 0.1).
The classification of CLPC into two types, local and general, in hydrogel lens wear was confirmed based on presentations at both sites. This distribution of papillae between local and general CLPC may indicate separate etiologies involved in the pathogenesis of the condition.
"Contact lens handling by contact lens wearers might contribute to contamination with keratins, as might interaction with the corneal and conjunctival epithelia , most likely through the mechanical force of a contact lens moving with every blink. There is evidence that protein accumulation and poor lens cleaning can contribute to clinical complications such as discomfort [3,25,26], reduced vision , infection [28,29], and inflammatory responses [30,31]. Increased deposits on contact lenses have been associated with increased corneal staining with fluorescein . "
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to quantify specific proteins deposited on daily wear silicone hydrogel lenses used in combination with multipurpose disinfecting solutions (MPDSs) by applying multiple-reaction-monitoring mass spectrometry (MRM-MS).
Balafilcon A or senofilcon A contact lenses used with different MPDSs on a daily wear schedule were collected. Each worn lens was extracted and then digested with trypsin. MRM-MS was applied to quantify the amounts of lysozyme, lactoferrin, lipocalin-1, proline-rich protein-4, and keratin-1 in the extracts.
The amount of protein extracted from the contact lenses was affected by the individual wearers, lens material, and type of care system used. Higher amounts of proteins were extracted from lenses after wear when they were used with an MPDS containing polyhexamethylene biguanide (PHMB) and poloxamer 407 compared with MPDSs containing polyquaternium-1 (PQ-1)/alexidine dihydrochloride with Tetronic 904 or PQ-1/ PHMB with poloxamine and sulfobetaine (p<0.05). There was a correlation between the amount of lipocalin-1 or keratin-1 extracted from lenses and symptoms of ocular dryness.
The MRM-MS technique is a promising approach that could be used to reveal associations of individual proteins deposited on lenses with performance of contact lenses during wear.
"Initial reports noted a prevalence of 6% CLPC with first generation silicone hydrogel lenses. This has reduced with lower modulus materials, although it has also been noted that the incidence of localized CLAPC is higher with silicone hydrogels compared to hydrogel lenses (3.6% compared to 0.7%) . The prevalence of SEALs, due to the mechanical pressure on the epithelium from the lens design or material, was around 7% with the first silicone hydrogel materials but has also reduced with lower modulus lenses to around 4%. Mucin balls are seen between the epithelium and the contact lens during eye closure due to the lens shearing the tear film and rolling it into small balls under the lens. "
[Show abstract][Hide abstract] ABSTRACT: To examine the relative changes in modulus of nine soft contact lens materials when exposed to three lens care solutions.
Measurements of elastic modulus were made using an Instron 3343 tensiometer of lenses which had been pre-soaked in ReNu Multi-Purpose (Bausch & Lomb), OPTI-FREE RepleniSH (Alcon), Clear Care (CIBA Vision) hydrogen peroxide, or a saline control solution for one week. The solutions were changed three times during the week-long soaking period. Following this, the lenses were measured for centre thickness and were cut into two samples of identical width. Young's modulus was measured in the force range of 0.015-0.035 N.
Measurements in saline ranged form 0.31MPa for etafilcon A to 1.76 MPa for lotrafilcon A. All of the lenses, with the exception of senofilcon A, displayed a significant change in modulus with at least one of the solutions. Both etafilcon A and lotrafilcon B showed a significant change in modulus with all solutions. With lotrafilcon B in hydrogen peroxide solution, modulus reduced from 1.32 to 0.93 MPa (P<0.0001). Galyfilcon A decreased from 0.36 to 0.31 MPa in ReNu Multi-Purpose (P<0.0001) and lotrafilcon A decreased from 1.76 to 1.64 MPa in OPTI-FREE RepleniSH (P=0.04). Comfilcon A increased from 0.78 to 0.85 MPa (P<0.0001) in peroxide.
The use of some contact lens-solution combinations results in significant changes in modulus. In the case of the multi-purpose solutions, the changes probably relate to uptake of the formulation components and, in the case of peroxide, to chemical changes to the polymer.
Contact lens & anterior eye: the journal of the British Contact Lens Association 10/2010; 33(5):210-4. DOI:10.1016/j.clae.2010.06.002 · 1.37 Impact Factor
"A variety of ocular complications during lens wear can be directly related to such deposition, particularly on soft contact lenses [11-16]. One particularly relevant complication is giant papillary conjunctivitis (GPC), which has been observed with a variety of materials and wearing schedules [14,15,17,18]. GPC has been closely linked with depositions of denatured proteins on the lens surface and potentially mechanical lens interactions with the under surface of the lids . "
[Show abstract][Hide abstract] ABSTRACT: To investigate the efficiency of lysozyme and albumin removal from silicone hydrogel and conventional contact lenses, using a polyhexamethylene biguanide multipurpose solution (MPS) in a soaking or rubbing/soaking application and a hydrogen peroxide system (H(2)O(2)).
Etafilcon A, lotrafilcon B and balafilcon A materials were incubated in protein solutions for up to 14 days. Lenses were either placed in radiolabeled protein to quantify the amount deposited or in fluorescent-conjugated protein to identify its location, using confocal laser scanning microscopy (CLSM). Lenses were either rinsed with PBS or soaked overnight in H(2)O(2) or MPS with and without lens rubbing.
After 14 days lysozyme was highest on etafilcon A (2,200 mug) >balafilcon A (50 microg) >lotrafilcon B (9.7 microg) and albumin was highest on balafilcon A (1.9 microg) =lotrafilcon B (1.8 microg) >etafilcon A (0.2 microg). Lysozyme removal was greatest for balafilcon A >etafilcon A >lotrafilcon B, with etafilcon A showing the most change in protein distribution. Albumin removal was highest from etafilcon A >balafilcon A >lotrafilcon B. H(2)O(2) exhibited greater lysozyme removal from etafilcon A compared to both MPS procedures (p<0.001) but performed similarly for lotrafilcon B and balafilcon A lenses (p>0.62). Albumin removal was solely material specific, while all care regimens performed to a similar degree (p>0.69).
Protein removal efficiency for the regimens evaluated depended on the lens material and protein type. Overall, lens rubbing with MPS before soaking did not reduce the protein content on the lenses compared to nonrubbed lenses (p=0.89).
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