Quantification of contact lens wettability after prolonged visual device use under low humidity conditions.

PURPOSE: Discomfort of silicone hydrogel (SiHy) contact lenses (CL) is associated with longer wearing time, demanding visual tasks, and dry environments. This study investigated the impact of challenging environmental conditions on thewettability of four daily disposable SiHy CL. METHODS: Habitual wearers of delefilcon A (n=32) and somofilcon A (n=32) were tested with their habitual lenses and with stenfilcon A and narafilcon A lenses. Digital videos were captured using non-invasive Tearscope illumination after 3 hrs of conventional wear and 3 hrs of computer use at 20% relative humidity (RH). Masked investigators analysed non-invasive break up time (NIBUT), minimum protected area (MPA) ofthe lens surface by the tear film, and dehydration speed (DS) over the interblink period after exposure to 20% RH. RESULTS: For habitual delefilcon A wearers, mean NIBUT was longer with delefilcon A (9.2 sec) than stenfilcon A (6.3 sec, p = 0.052) and narafilcon A (5.1 sec, p = 0.006); mean MPA was significantly higher with delefilcon A (95.4%)than stenfilcon A (84.4%, p = 0.002) and narafilcon A (82.9%, p = 0.006); mean DS was lower with delefilcon A (0.28 mm2/sec) than stenfilcon A (0.81 mm2/sec, p = 0.002) and narafilcon A (0.60 mm2/sec, p = 0.056). For habitual somofilcon A wearers, mean MPA was lower for narafilcon A (76.2%) than for somofilcon A (89.0%, p < 0.001) but not stenfilcon A (88.4%, p = 0.748) and mean DS was higher for narafilcon A (0.96 mm2/sec) than somofilcon A (0.60mm2/sec, p = 0.029) but not stenfilcon A (0.51 mm2/sec, p = 0.701). CONCLUSIONS: Delefilcon A CL performed betterthan stenfilcon A and narafilcon A after 6 hrs of wear including 3 hrs intensive visual tasks under challenging environmental conditions. Delefilcon A CL may be preferable for CL wearers with intensive computers and/or digital devices usage.

The influence of lens care systems on eyelid tissue changes during silicone hydrogel contact lens wear.

PURPOSE: To compare the effects of a hydrogen peroxide (H2O2)-based lens care solution and a polyhexamethylene biguanide (PHMB) multi-purpose solution on the eyelids when used with silicone hydrogel (SiHy) contact lenses. METHODS: A total of 74 symptomatic wearers of ACUVUE® OASYS® (senofilcon A; n = 39) or PureVision® (balafilcon A; n = 35) contact lenses were randomised 1:1 to either CLEAR CARE® Cleaning & Disinfecting Solution or renu® fresh™ multi-purpose solution (n = 37 each). Assessments of hyperaemia, papillae and lid margin staining of eyelid tissue were evaluated subjectively by a masked investigator at enrolment (with the subjects' habitual SiHy contact lenses and PHMB-preserved care systems), at dispensing visit (when no lenses were worn) and at 3-months' follow-up. RESULTS: There were no differences in eyelid assessments between the two lens care groups at dispensing visit (p = 0.086 to 0.947). After 3 months, the papillae response was significantly less marked with H2O2-based solution than with PHMB-based solution (p = 0.017). Lid hyperaemia (p < 0.001) and papillae (p = 0.002) were also significantly reduced. Although lid hyperaemia was also reduced with PHMB-based solution (p < 0.001), there was no concurrent decrease in papillae response (p = 0.051). No improvements were found in eyelid margin staining either over time or between the two lens care groups. CONCLUSION: In symptomatic contact lens wearers, a H2O2-based lens care solution used with senofilcon A and balafilcon A lenses was better tolerated by eyelid tissues than was a PHMB-based solution and led to a decrease in clinical markers of eyelid inflammation.

Elemental Composition at Silicone Hydrogel Contact Lens Surfaces.

OBJECTIVES: The outermost surface composition of 11 silicone hydrogel (SiHy) lenses was measured using X-ray photoelectron spectroscopy (XPS) to understand differences in wettability and potential interactions within an ocular environment. The SiHy lenses tested included balafilcon A, lotrafilcon A, lotrafilcon B, senofilcon A, comfilcon A, and somofilcon A reusable 2-week or monthly replacement lenses and delefilcon A, samfilcon A, narafilcon A, stenfilcon A, and somofilcon A daily disposable lenses. METHODS: All lenses were soaked for 24 hr in phosphate-buffered saline to remove all packaging solution and dried under vacuum overnight before analysis. X-ray photoelectron spectroscopy measurements were performed at 2 take-off angles, 55° and 75°, to evaluate changes in elemental composition as a function of depth from the surface. RESULTS: Detailed analysis of the XPS data revealed distinct differences in the chemical makeup of the different lens types. For all lenses, carbon, oxygen, and nitrogen were observed in varying quantities. In addition, fluorine was detected at the outermost surface region of comfilcon A (3.4%) and lotrafilcon A and B (<0.5%). The silicon content of the near-surface region analyzed varied among lens types, ranging from a low of 1.6% (lotrafilcon B) to a high of 16.5% (comfilcon A). In most instances, silicon enrichment at the outermost surface was observed, resulting from differences in lens formulation and design. CONCLUSIONS: Lenses differed most in their surface silicon concentration, with lotrafilcon B and delefilcon A exhibiting the lowest silicon contents and comfilcon A lens exhibiting the highest. Silicon has hydrophobic properties, which, when found at the surface, may influence the wettability of the contact lenses and their interaction with the tear film and ocular tissues. Higher surface silicon contents have been previously correlated with adverse effects, such as enhanced lipid uptake, thus underscoring the importance of monitoring their presence.

Effect of lens care system on silicone hydrogel contact lens wettability.

PURPOSE: The purpose was to compare the effect of the repeated usage of two care systems (one hydrogen peroxide cleaning and disinfecting system and one polyaminopropyl biguanide (PHMB) containing multi-purpose system) with silicone hydrogel contact lenses worn for three months on a daily wear modality. A specific aspect of interest was of the effect of the care systems on contact lens wettability. METHODS: Seventy-four symptomatic contact lens wearers, habitually wearing either ACUVUE(®) OASYS(®) (n=37) or PureVision™ (n=37), constituted the study population. The study was a two-arm prospective, investigator-masked, bilateral study of three-month duration to evaluate the effects of CLEAR CARE(®) compared with renu(®) fresh™. The subjects were randomized to one of the two lens care systems. Contact lens wettability and surface cleanliness were assessed with the Tearscope and reported in terms of pre-lens non-invasive break-up time (PL-NIBUT) and visible deposits. Baseline assessments at enrollment were with the subjects' own contact lenses worn for at least 6h when using their habitual PHMB-preserved care system and at the dispensing visit with new contact lenses. At the follow-up visits, the contact lenses were worn for at least 6h, and were at least 11 days old for ACUVUE(®) OASYS(®) and 25 days old for PureVision™. RESULTS: The results obtained showed that: (i) with CLEAR CARE(®), a significant improvement in contact lens wettability was recorded compared with the habitual care system at the three-month follow-up visit (mean median PL-NIBUT 5.8 vs. 4.0 s, p<0.001). Further, with this same lens care system a significant increase in wettability was observed at the three-month follow-up visit compared with dispensing (mean median PL-NIBUT 5.8 vs. 4.5s, p=0.022). (ii) Whereas no difference in contact lens wettability was observed at dispensing between the two lens care groups (mean PL-NIBUT: 4.5 vs. 4.2s, p=0.518), a significantly more stable pre-lens tear film was observed with CLEAR CARE(®) than with renu(®) fresh™ at both the two-month (mean PL-NIBUT: 4.6 vs. 3.7s, p=0.005) and three-month (mean PL-NIBUT: 5.8 vs. 4.2 s, p=0.028) visits. iii. With renu(®) fresh™, no significant differences were observed at the end of three months of use compared with either the habitual care system or the new contact lens solution (mean PL-NIBUT: 3M 4.2 vs. Disp 4.2 s (p=0.420) vs. enrolment habitual care solution 5.1s (p=0.734)). iv. With CLEAR CARE(®) significant increases in the incidence of surfaces free of both mucus (3 month 95%. vs. habitual solution 82% enrolment; p=0.005) and lipid (3 month 87% vs. habitual solution 72% enrolment; p=0.009) were observed. CONCLUSION: Significantly better contact lens wettability and surface cleanliness were achieved for ACUVUE(®) OASYS(®) and PureVision™ with CLEAR CARE(®) than with renu(®) fresh™ at the end of three months of use.

Contact lens lipid spoliation of hydrogel and silicone hydrogel lenses.

PURPOSE: The purpose of the study was to measure contact lens lipid spoliation of silicone hydrogel PureVision (balafilcon A) and hydrogel Acuvue 2 (etafilcon A) contact lenses worn for 10 hours single use (DD) and 7 days of extended wear (EW). METHODS: Two similar study populations (DD, n = 55; EW, n = 53), were enrolled at four study sites. In each population, a bilateral, randomized, crossover (lens material), subject-masked experimental design was followed. Worn contact lenses were analyzed for lipid uptake using high-performance liquid chromatography by two laboratories: Alcon Laboratories (right lens total uptake) and OTG Research & Consultancy (left lens total uptake and individual lipid classes). RESULTS: Lipid uptake was different for the two materials: total lipid (p < 0.007), cholesterol esters (p < 0.001), cholesterol (p < 0.001 EW only), and triglycerides/phospholipids (p < 0.001) were higher for balafilcon A, whereas fatty acid (p < 0.0025 EW only) was higher for etafilcon A. The ratio of the extracted lipids was also different: higher percentages of triglycerides/phospholipids (p < 0.001) and cholesterol (p < 0.001 EW only) for balafilcon A and higher percentages of fatty acids/di- and monoglycerides (p < 0.014) for etafilcon A. CONCLUSIONS: Total lipid uptake was highly material dependent. Both laboratories measured a greater uptake of lipids by the silicone hydrogel than the hydrogel material, a difference that was evident after only 10 hours of DD. Total lipid uptake was greater after 7 days of EW compared with 10 hours of DD. Of interest for contact lens spoliation and its avoidance was the differential lipid uptake profile, indicating material selectivity. Whereas greater differentiation between materials was possible after 7 days of EW for each material, the lipid uptake profile was similar for DD and EW, indicating a greater material effect than a wear modality effect.

Symptomatic relief associated with eyelid hygiene in anterior blepharitis and MGD.

OBJECTIVE: The principal objective of this investigation was to assess the symptomatic relief associated with eyelid hygiene using Blephaclean eye pads, a cosmetic product, to manage anterior blepharitis or Meibomian gland dysfunction (MGD) associated with dry eye complaints. METHOD: The investigation was a bilateral, prospective, interventional open label investigation of 3-month duration. The test population was made up of dry eye sufferers with at least mild symptoms (Ocular Surface Disease Index [OSDI] ≥13) who presented with mild to moderate anterior blepharitis or MGD. Eyelid hygiene was intensive (twice a day) for the initial 3 weeks and a maintenance regimen (once a day) for the remainder of the study. At each visit, a detailed assessment of symptomatology was carried out. The assessment included the reporting of overall symptomatology with the OSDI questionnaire, of comfort and specific symptoms at the end of the day on 100-point visual analog scales and of specific MGD-related symptoms on forced choice 5-point scales. RESULT: Forty subjects aged 22 to 74 years (54±15 years) were enrolled, of whom 39 completed the investigation. The product usage revealed good overall compliance throughout the study. The results revealed significant improvement in symptomatology. A significant (P<0.001) decrease in overall symptomatology was recorded (Mean OSDI: baseline=30, day 21=18, day 90=19; Symptomatic status: baseline 100%, day 21 55%, day 90 54%) associated with significant (P<0.001) increase in the end of day comfort (Mean score: baseline=56, day 21=67, day 90=67) and decrease in end of day dryness (Mean score: baseline=55, day 21=42, day 90=41). CONCLUSIONS: The results showed that eyelid hygiene with Blephaclean wipes by subjects with anterior blepharitis or MGD significantly decreased their associated symptomatology and increased their ocular comfort. The data confirmed the efficiency of the clinical methodology, put forward of 3 weeks of intensive use (twice a day) of eyelid wipes followed by maintenance use (once a day); that approach achieved a rapid symptomatic improvement that was maintained over time.

Eyelid margin modification associated with eyelid hygiene in anterior blepharitis and meibomian gland dysfunction.

OBJECTIVE: To assess the changes in eyelid margins associated with eyelid hygiene using Blephaclean eye pads to manage anterior blepharitis or meibomian gland dysfunction (MGD) associated with dry eye complaints. METHOD: The investigation was a bilateral, prospective, interventional, open-label investigation of 3-month duration. The test population included dry eye sufferers with at least mild symptoms (Ocular Surface Disease Index ≥ 13) who presented with mild to moderate anterior blepharitis or MGD. Eyelid hygiene was intensive (twice a day) for the initial 3 weeks and a maintenance regimen (once a day) for the remainder of the study. At each visit, a detailed assessment of eyelid margins was performed. This assessment included the rating of lashes contamination, lid margin foam, droplet, redness and staining, and meibomian gland blockage, dropout, and expression. RESULT: Forty subjects aged 22 to 74 years (54 ± 15 years) were enrolled of whom 39 completed the investigation. The product usage revealed good overall compliance throughout the study. The results revealed a significant improvement in eyelid margin status. Significant (P<0.001) decrease in contamination of eyelashes and meibomian gland blockage were recorded at the completion of the initial 3-week intensive phase and maintained over the 3-month study during the maintenance phase. Meibomian gland expression, indicative of the glands functionality, was also significantly better at the completion of both study phases (intensive P=0.003; maintenance P=0.001). A decrease in eyelid margin staining was also observed but was only significant at the 3-month follow-up at the completion of the maintenance phase. CONCLUSION: The results showed that eyelid hygiene with Blephaclean wipes by subjects with anterior blepharitis or MGD significantly improved the status of the eyelid margin tissues including the meibomian glands. The data confirmed the efficiency of the clinical methodology put forward of 3 weeks of intensive use (twice a day) of eyelid wipes followed by maintenance use (once a day) and that approach achieved a rapid improvement in tissue status and gland patency.

Long term effects of the daily wear of senofilcon a silicone hydrogel contact lenses on eyelid tissues.

PURPOSE: Eyelid changes have been reported with silicone hydrogel contact lenses. It is hypothesized that those changes are associated with the mechanical interaction between the contact lens front surface and eyelid tissues and, are specific to contact lens type rather than a general effect of the lens category. The purpose of this study was to assess the effect of refitting into a silicone hydrogel on a daily wear basis to current contact lens wearers, lapsed wearers and neophytes on eyelid physiology. METHODS: The investigation was a 2-year prospective investigation of ACUVUE® OASYS® with HYDRACLEAR® Plus (senofilcon A) used with care systems, representative of current practice. RESULTS: 90 subjects were enrolled of whom 64 subjects completed the investigation. The results obtained were as follows: CONCLUSIONS: The results of the study demonstrated that senofilcon A, worn on a daily wear basis and replaced every 2 weeks, did not produce any eyelid tissue changes in previous non-contact lens wearers at baseline and revealed no change or a slight improvement of the eyelid tissues of established contact lens wearers.

Contact lens-induced circumlimbal staining in silicone hydrogel contact lenses worn on a daily wear basis.

OBJECTIVES: The principal objective of the study was to measure the conjunctival staining produced in the circumlimbal region by silicone hydrogel contact lenses with different edge designs. The secondary objective was to investigate the association between circumlimbal staining and comfort. METHODS: Four silicone hydrogel contact lenses: ACUVUE OASYS (knife edge design), AIR OPTIX, Biofinity (chisel edge rounded edge combination), and PureVision (rounded edge design), and 1 hydrogel contact lens, ACUVUE 2 (knife edge design), were tested. The study was conducted on a cohort population of 27 established soft contact lens wearers, who wore each contact lens type, in a random order, for a period of 10 (±2) days. Circumlimbal staining was measured in a double-masked fashion through image analysis of digital photographs of lissamine green taken under controlled experimental conditions. RESULTS: The results obtained showed that contact lens edge design was the primary factor controlling circumlimbal staining for silicone hydrogel lenses: a rounded edge away from the ocular surface produced the lowest staining (average, 0.19%) and a knife edge in close apposition to the ocular surface produced the highest staining (average, 1.34%). Contact lens material rigidity was also identified to affect circumlimbal staining and an inverse association between circumlimbal staining and contact lens comfort was demonstrated: the rounded edge design produced the lowest comfort (72 of 100) and the knife edge design produced the highest (87 out of 100). CONCLUSION: Soft contact lens wear induces circumlimbal staining, the level of staining being influenced by the contact lens edge design. However, high level of circumlimbal staining is not associated with decreased comfort.

Long-term effects of the extended wear of senofilcon A silicone hydrogel contact lenses on ocular tissues.

PURPOSE: The objective of the investigation was to show that, because of their overall properties, Acuvue® Oasys™ with Hydraclear™ Plus brand (senofilcon A) silicone hydrogel contact lenses achieve excellent ocular tissue tolerance during long-term extended wear. METHODS: The investigation was a 2-year, prospective, extended wear investigation of senofilcon A silicone hydrogel contact lenses worn for up to 6 nights without removal. RESULTS: The 2-year results compared with the subjects' baseline ocular statuses on entering the study revealed: CONCLUSIONS: The quantification of the effects on the ocular tissues of 2 years of extended wear of senofilcon A, by mainly previously successful daily soft contact lens wearers, found an excellent biocompatibility. The results support the hypothesis that senofilcon A contact lenses, when worn on a 6-night/7-day extended wear regimen, maintain excellent long-term ocular tissue tolerance.

Long-term effects of the daily wear of senofilcon A silicone hydrogel contact lenses on corneal and conjunctival tissues.

PURPOSE: The objective of the investigation was to show that, because of their overall properties, Acuvue® Oasys™ with Hydraclear® Plus brand (senofilcon A) silicone hydrogel contact lenses achieve excellent ocular tissue tolerance during long-term daily wear. METHODS: The 2-year investigation was a prospective daily wear analysis of Acuvue® Oasys™ with Hydraclear® Plus (senofilcon A) silicone hydrogel contact lenses replaced every 2 weeks and used in conjunction with a representative range of care systems. RESULTS: The 2-year results compared with the subjects' baseline ocular status on entering the study revealed: CONCLUSIONS: The quantification of the effects on the ocular tissues of 2 years of daily wear of senofilcon A, by mainly previously successful daily soft contact lens wearers, showed an excellent biocompatibility. The results support the hypothesis that senofilcon A contact lenses, when worn on a 2-week daily wear regimen, maintain excellent long-term ocular tissue tolerance.

Tear film evaporation--effect of age and gender.

PURPOSE: Dry eye is more prevalent in older patients and among them more marked in women than men. The increase in dry eye with aging is traditionally thought to be associated with a decrease in tear production enhanced by hormonal changes. Clinical evidence of an abnormal lipid production system in older patients, in particular women is established. It is therefore postulated that the greater prevalence of dry eye problems in an older population has an evaporative component. METHODS: Tear film evaporation was measured with the Oregon Health Sciences University Evaporimeter at 30% and 40% humidity. RESULTS: 160 subjects less than 45 years old and 57 subjects aged 45 years or more formed the study population. The results revealed a significant effect of age (p < 0.001), gender (p < 0.001) and their interaction (p < 0.001): (i) the rate of evaporation was higher in the older age group at both humidities; (ii) the rate of evaporation was overall higher for women; and (iii) the synergic effect of age and gender was very marked: the rate of evaporation of older women was 34-80% higher than that of older men and 36-69% than younger women. CONCLUSIONS: Aging of the tear film includes a significant evaporative component characterised by higher tear film evaporation for the over 45 compared to younger people. Further, in the over 45 years of age, a significantly greater tear film evaporation was recorded in women than men. The findings have significant implications for the management of presbyopic dry eye sufferers.

Tear film dynamics and lipid layer characteristics--effect of age and gender.

PURPOSE: Dry eye disease is significantly more prevalent in older subjects and among them more marked in women than men. Further, it is established that the tear film dynamics of dry eye sufferers is different to that of normal. It is therefore postulated that the greater prevalence of dry eye problems with advancing age is at least in part related to poorer tear film dynamics. METHODS: Tear film dynamics (non-invasive break up time) and lipid characteristics (lipid layer thickness and contamination) were assessed using the Tearscope lighting system. RESULTS: 160 Subjects less than 45 years old and 58 subjects aged 45 years or more formed the study populations. The tear film stability was mostly influenced by age; the break up time was statistically significantly shorter for the older age group (p < 0.001). The lipid layer was also significantly thinner (p = 0.013) for the subjects aged 45 years or older with a very marked synergic effect of age and gender. The lipid layer of older women was significantly thinner and more contaminated than that of younger women (p = 0.002 and < 0.001) and of older men (p = 0.034 and 0.004). CONCLUSIONS: Aging of the tear film is characterised by its destabilisation associated with significant changes in the tear lipid layer producing less protection from evaporation in the older population; the observed changes are more marked in women than in men. The findings have significant implications for the management of presbyopic dry eye sufferers, for whom decreasing evaporative problems is essential.

Effect of castor oil emulsion eyedrops on tear film composition and stability.

PURPOSE: An emulsion eyedrop containing castor oil has been shown to modify the tear film lipid layer and increase tear film stability. The primary objectives of this investigation were to measure the prevalence of castor oil in the tear fluid over time and quantify the effects on the lipid layer. A secondary objective was to quantify the initial effects on ocular symptomatology. METHODS: The investigation was an open label pilot study on 5 normal and 10 dry eye subjects. A single eyedrop (Castor oil emulsion, Allergan) was instilled in each eye; the tear film appearance and composition were monitored for 4h via in vivo visualisation using the Tearscope and post in vivo tear samples analysis by HPLC. RESULTS: Combined results for both normal and dry eye subjects showed that castor oil was detected up to 4h after a single eyedrop instillation and associated with an increase in the level of tear film lipid. The relative amount of various lipid families was also changed. An increase in tear lipid layer thickness was significant up to one hour post-instillation for the symptomatic sub-population. The changes in tear film characteristics were associated with significantly lower symptoms up to four hours post-instillation for the symptomatic sub-population. CONCLUSION: This pilot investigation showed that castor oil eyedrops achieved a residence time of at least four hours post-instillation, producing a more stable tear film and an associated significant decrease in ocular symptoms over the entire follow-up period for the symptomatic subjects.

Contact lens wear affects tear film evaporation.

PURPOSE: The aim of the study was to measure tear film evaporation of both contact lens wearers (CLW) and nonwearers. The hypotheses tested were that (i) amongst CLW tear film evaporation was higher when contact lenses are worn and (ii) tear film evaporation of CLW was higher than nonwearers in the absence of contact lenses. METHODS: Tear film evaporation rate was measured at 30% and 40% mean humidity. The subjects were divided into 3 groups: (i) CLW wearing contact lenses (n = 111 subjects or 222 eyes), (ii) CLW having not worn contact lenses on the day of the visit (CLW no CL n = 129 subjects or 258 eyes), and (iii) Non-contact lens wearers (NW) (n = 139 subjects or 278 eyes). RESULTS: The rate of evaporation was similar for the right and left eyes at both humidities. The rate of evaporation was significantly higher for the CLW, than for both CLW no CL and NW. The decrease in the rate of evaporation between the dry (30%) and normal (40%) environmental conditions was significantly lower for the CLW than for the NW. Further, the evaporation rate was significantly greater for the CLW, even after 1 day without contact lens wear, than for the nonwearers. CONCLUSIONS: The investigation demonstrates that the rate of evaporation is higher in the presence of a contact lens; the effect may be associated with tissue and/or tear film changes as it is, in part, still present 24 hours after contact lens wear. Wearing contact lenses in normal humidity conditions (40%) produces a greater evaporation than that experienced by non-contact lens wearers in low humidity (30%). This could explain the higher prevalence of dry eye complaints among CLW than amongst nonwearers. The study results support the hypothesis of increased evaporation as a contributing factor to contact lens induced dry eyes.

Use of silicone hydrogel material for daily wear.

Silicone hydrogel contact lenses were initially developed to optimise oxygen transmissibility for extended wear use. The concerns with such contact lenses have been their higher elastomeric and hydrophobic characteristics associated with the incorporation of silicone type monomers. The use of silicone hydrogel has most recently been suggested for daily wear to eliminate all hypoxic related problems. The primary aim of the investigation was to test in vivo wetting performance and subjective acceptance of the first silicone hydrogel contact lens developed for daily wear, ACUVUE ADVANCE with HYDRACLEAR (galyfilcon A), compared to a conventional hydrogel contact lens for the same application SofLens 66 (alphafilcon A). The investigation was a randomised, subject masked bilateral cross over investigation testing of the two contact lens materials over their approved replacement periods (galyfilcon A 2 weeks and alphafilcon A 2 weeks (USA) and 4 weeks (Europe)). In all cases ReNu Multiplus lens care system was used. The investigation carried out on 24 contact lens wearers showed that: (i) in vivo wettability was superior for galyfilcon A which had a thicker lipid layer (thin layer incidence: galyfilcon A 54%; alphafilcon A 70-86%, p<0.05), a thicker aqueous layer (thick layer incidence: galyfilcon A 88%; alphafilcon A 35-64%, p<0.05) and a more stable tear film (galyfilcon A 7.8s; alphafilcon A 2 weeks 5.6s, p=0.022; 4 weeks 7.4s, p=0.276); (ii) for the intended replacement period, comfort was better with galyfilcon A (2 weeks) compared to alphafilcon A (4 weeks) at insertion (p=0.001) and, throughout the day (daytime and evening p=0.008). Contact lenses made from galyfilcon A and replaced two weekly achieved better in vivo wettability than contact lenses made from alphafilcon A and replaced either two and four weekly; the better wettability was associated with an overall better comfort for galyfilcon A.

Bulbar conjunctival staining in contact lens wearers and non lens wearers and its association with symptomatology.

It has become increasingly apparent that bulbar conjunctival anomalies are associated with dry eye symptoms. Lissamine green (LG) and sodium fluorescein (FL) conjunctival staining were assessed in 102 soft contact lens wearers and 79 non contact lens wearers. Conjunctival staining was increased in symptomatic patients. Both LG and FL staining were discriminating factors for symptomatic non lens wearers (>or=grade 1.5, p<0.001). Only LG staining could discriminate symptomatic from asymptomatic lens wearers (>or=grade 1.0, p=0.007). This analysis confirms the involvement of the conjunctiva in dry eye symptomatology. While both stains are useful, LG shows greater specificity for symptomatic subjects, particularly in contact lens wearer. It is recommended that the examination of patients complaining of dry eyes, in particular contact lens wearing patients include as routine, the examination of the conjunctiva with lissamine green.

Dry eye symptomatology of soft contact lens wearers and nonwearers.

PURPOSE: This study attempted to identify the questions most suitable to detect dry eye in a contact lens-wearing and noncontact lens-wearing population to optimize history-taking in routine practice. METHODS: The McMonnies questionnaire was applied to both soft contact lens wearers and nonwearers attending the clinic for routine screening. The test population in this retrospective analysis was made up of 502 daily soft contact lens wearers (SCLW) and 309 noncontact lens wearers (NCLW). The diagnostic value of individual questions was determined by CHAID analysis. RESULTS: Forty-three percent of soft contact lens wearers were identified as symptomatic, of whom 28% had moderate to severe symptoms. In comparison, 15% of age-matched noncontact lens wearers were symptomatic, 5% at moderate or severe level. The question on frequency of dryness had the highest diagnostic value. Of those who had "never" experienced dryness, 87% of SCLW and 95% of NCLW were judged normal as per the questionnaire; this increased to 94% and 99%, respectively, if they also "never" experienced scratchiness (SCLW) and "never" experienced burning (NCLW). In SCLW, if dryness was experienced often, the subjects were found to be symptomatic in 90% of cases. This figure rose to 96% if the response yes was given to "sensitivity to smoke." Systemic associations were found to be more relevant to NCLW. CONCLUSIONS: The most predictive question for the detection of dry eye was frequency of ocular dryness. Scratchiness, burning symptoms, and sensitivity to cigarette smoke and to make-up products were additional indicators.