Repeatability of lipid layer thickness using LipiView® following removal of contact lenses and its relationship to comfort.

Purpose: To assess the repeatability of lipid layer thickness (LLT) measurement using the LipiView® interferometer after daily disposable contact lens (CL) wear and correlation with ocular comfort in soft contact lens wearers.

Methods: A prospective study was conducted over two consecutive months, wherein CL wearers (n = 20) wore either Somofilcon A or Verofilcon A daily disposable CLs in a crossover design, switching lenses after 1 month. The pre-corneal tear film LLT was measured at the end of each month after CLs had been worn for at least 6 h.

Meibomian Gland Shortening Is Associated With Altered Meibum Composition.

Purpose: The purpose of this study was to investigate differences in the composition of meibum extracted from human meibomian glands displaying different morphological characteristics.

Methods: Adult participants with evidence of meibomian gland shortening were enrolled. Glands were observed using infrared meibography, and meibum was collected from one short and one long gland from the lower eyelid of the same eye.

Lipid-based eye drop formulations for the management of evaporative dry eyes.

Dry eye disease is a progressive prevalent ocular surface disorder that arises from various factors and is characterized by insufficient quality and/or quantity of tears. The underlying pathophysiology is intricate and can progress to chronic, difficult-to-treat conditions. Multiple strategies and therapeutic approaches are utilized in its management that target one or more etiopathological components of dry eyes, which may include aqueous tear deficiency or evaporative dry eyes.

Biochemistry of human tear film: A review.

The precorneal tear film is a complex mixture of proteins, lipids, metabolites, and electrolytes with different structures and functionalities. Sustainable production of each tear component is vital to the health of the ocular surface. Abnormalities in the tear film components may reflect alterations in the health of the ocular surface or the presence of systemic disease.

Development of an enzymatic method for the evaluation of protein deposition on contact lenses.

The aim of this study was to evaluate a new digestion method to quantify protein deposition on contact lenses. Four silicone hydrogel and one hydrogel contact lens material were incubated in lactoferrin, lysozyme, immunoglobulin A, and bovine serum albumin solutions at approximate physiological concentrations and temperature. Immobilized trypsin was used to digest the protein deposits from the contact lens surfaces.

A method for studying lipid adsorption to silicone hydrogel contact lenses.

The aim of this study was to develop an experimental methodology to measure lipid deposition with contact lenses. Contact lenses were incubated in a lipid solution. The amount and types of adsorbed lipids were assessed using mass spectrometry and confocal microscopy.

Profiling of non-polar lipids in tears of contact lens wearers during the day.

Purpose: This study explored whether the non-polar lipids in the human tear fluid lipidome show diurnal variation with and without contact lens wear. It also addressed the relationship between changes in ocular comfort during the day with the level of non-polar lipids.

Methods: Tear samples were collected in the morning and evening with and without contact lenses using fine glass capillary tubes and were analysed by chip-based nano-electrospray ionization tandem mass spectrometric techniques.

CLEAR - Contact lens wettability, cleaning, disinfection and interactions with tears.

Contact lens materials have undergone significant changes over the past 20 years, particularly with respect to the introduction of silicone hydrogel materials. Whilst this development addressed hypoxic issues, other important areas relating to contact lens success, notably comfort, require further research. Contact lens wettability remains a crucially important part of biocompatibility.

Differences in Tear Film Biochemistry of Symptomatic and Asymptomatic Lens Wearers.

Significance: The concentration of selected proteins and inflammatory mediators in tears of symptomatic and asymptomatic contact lens wearers were quantified. The level of leukotriene B4 was higher in the symptomatic group. This may suggest that inflammation can be the cause of discomfort sensation at the end of day.

Relation between Ocular Comfort, Arachidonic Acid Mediators, and Histamine.

Purpose: Contact lenses are associated with discomfort during wear. This may be the result of stimulation of the ocular surface and production of pro-inflammatory mediators which are then released into the tears. This study examined changes in the concentration in tears of arachidonic acid metabolites (AAM) prostaglandins, cysteinyl leukotrienes, and resolvin-D, as well as histamine in a general contact lens population in the morning and evening.

Evaluation of Protamine as a Disinfectant for Contact Lenses.

Purpose: To investigate the ability of protamine, alone or in combination with other antimicrobial agents, to kill bacteria and fungi associated with contact lens-related keratitis.

Methods: The International Organization for Standardization 14729:2001 procedure was used to test the antimicrobial activity of solutions of protamine (23-228 μM) with and without polyhexamethylene biguanide (PHMB) and ethylenediamine tetra-acetic acid (EDTA). The recommended ISO panel of microbes along with six clinical isolates was tested.

Contact Lens-Induced Discomfort and Protein Changes in Tears.

Purpose: Ocular discomfort is among the main causes of contact lens wear discontinuation. This study investigated the association between subjective ocular comfort ratings and diurnal changes in tear protein concentrations with and without contact lens wear.

Methods: The study was a prospective, open-label, single-group two-staged investigation.

Contact Lens-Induced Discomfort and Inflammatory Mediator Changes in Tears.

Purpose: Studies indicate that contact lens (CL) discontinuation mostly occurs because of dryness and discomfort symptoms. This study aimed to investigate relationships between changes in the concentration of tear inflammatory mediators with subjective comfort ratings with CL wear and no contact lens wear between morning and evening.

Method: Forty-five subjects collected tears twice daily in the morning and in the evening with or without lenses.

Method development for quantification of five tear proteins using selected reaction monitoring (SRM) mass spectrometry.

Purpose: To establish the use of selected reaction monitoring (SRM) mass spectrometry for quantification of tear proteins.

Methods: Tear samples were collected on multiple occasions (7-10 days) from healthy subjects with contact lens wear (CL = 3) and without contact lens wear (NCL = 4). Tear proteins were denatured using 8M urea, reduced with iodoacetamide, precipitated by acetone, and digested using trypsin.

Bacterial adhesion to unworn and worn silicone hydrogel lenses.

Purpose: The objective of this study was to determine the bacterial adhesion to various silicone hydrogel lens materials and to determine whether lens wear modulated adhesion.

Methods: Bacterial adhesion (total and viable cells) of Staphylococcus aureus (31, 38, and ATCC 6538) and Pseudomonas aeruginosa (6294, 6206, and GSU-3) to 10 commercially available different unworn and worn silicone hydrogel lenses was measured. Results of adhesion were correlated to polymer and surface properties of contact lenses.

Importance of rub and rinse in use of multipurpose contact lens solution.

Purpose: The introduction of contact lens multipurpose disinfection solution (MPDS) that can be used in conjunction with a "no-rub" regimen has simplified lens care requirements. Once adhered to a surface, microorganisms can become less susceptible to disinfection. The aim of the study was to evaluate the effect of various regimen steps on the efficacy of MPDS when used with silicone hydrogel and conventional lenses.

Soft contact lens disinfection solution efficacy: clinical Fusarium isolates vs. ATCC 36031.

Purpose: To compare the disinfecting efficacy of five soft contact lens multipurpose disinfection solutions (MPDS) against Fusarium solani clinical isolates and the ISO standard ATCC 36031 strain.

Methods: Three commercially available and two recalled MPDS were tested using the ISO/CD 14,729 stand-alone test for contact lens care products against 10 ocular isolates of F. solani and the ATCC 36031 strain.