Focus Night Research Articles

Do swimming goggles limit microbial contamination of contact lenses?

Purpose Wearing goggles over contact lenses while swimming is often recommended by eye care professionals. Limited data are available to assess this recommendation. The purpose of this study was to examine whether wearing goggles while swimming limits bacterial colonization on contact lenses and whether the type of lens worn affects contamination rates. Methods Twenty-three subjects underwent two swimming sessions at an ocean (salt water) pool (Maroubra beach Rock Pool, Sydney, Australia). Silicone hydrogel (Ciba Focus Night and Day) or hydrogel lenses (Ciba Focus Daily) were inserted into subjects' eyes before 30 min of swimming sessions, and subjects used modified goggles to mimic goggled and non-goggled conditions. At the end of each session, lenses were collected for microbial investigation. Viable bacterial colonies were classified as gram positive and gram negative and enumerated. The level of bacterial colonization on contact lenses between goggled and non-goggled conditions and between the two lens materials were compared. Results The range of colony forming units recovered from goggled lenses were 0 to 930 compared with 0 to 1210 on non-goggled lenses. The majority of subjects (16/23) had more microorganisms in the non-goggled condition than when wearing goggles (p = 0.03). Gram negative organisms were found in three non-goggled lenses. No significant difference was shown in the number of bacteria isolated from silicone hydrogel and hydrogel lenses (p > 0.6) irrespective of wearing goggles. Water samples had consistently higher numbers of bacterial counts than those adhered to the lenses; however, no association was found between the number of bacteria in the water sample and those found on the contact lenses. Conclusions Consistently, fewer bacterial colonies were found on the goggled contact lens, thus suggesting goggles offer some protection against bacterial colonization of contact lenses while swimming. These data would support the recommendation encouraging lens wearers to use goggles while swimming.

Do Swimming Goggles Limit Microbial Contamination of Contact Lenses?

Wearing goggles over contact lenses while swimming is often recommended by eye care professionals. Limited data are available to assess this recommendation. The purpose of this study was to examine whether wearing goggles while swimming limits bacterial colonization on contact lenses and whether the type of lens worn affects contamination rates. Twenty-three subjects underwent two swimming sessions at an ocean (salt water) pool (Maroubra beach Rock Pool, Sydney, Australia). Silicone hydrogel (Ciba Focus Night and Day) or hydrogel lenses (Ciba Focus Daily) were inserted into subjects' eyes before 30 min of swimming sessions, and subjects used modified goggles to mimic goggled and non-goggled conditions. At the end of each session, lenses were collected for microbial investigation. Viable bacterial colonies were classified as gram positive and gram negative and enumerated. The level of bacterial colonization on contact lenses between goggled and non-goggled conditions and between the two lens materials were compared. The range of colony forming units recovered from goggled lenses were 0 to 930 compared with 0 to 1210 on non-goggled lenses. The majority of subjects (16/23) had more microorganisms in the non-goggled condition than when wearing goggles (p = 0.03). Gram negative organisms were found in three non-goggled lenses. No significant difference was shown in the number of bacteria isolated from silicone hydrogel and hydrogel lenses (p > 0.6) irrespective of wearing goggles. Water samples had consistently higher numbers of bacterial counts than those adhered to the lenses; however, no association was found between the number of bacteria in the water sample and those found on the contact lenses. Consistently, fewer bacterial colonies were found on the goggled contact lens, thus suggesting goggles offer some protection against bacterial colonization of contact lenses while swimming. These data would support the recommendation encouraging lens wearers to use goggles while swimming.

The Effect of Surface Treatment of Silicone Hydrogel Contact Lenses on the Attachment of Acanthamoeba castellanii Trophozoites

To determine if plasma surface treatment of Focus Night & Day silicone hydrogel contact lenses affects the attachment of Acanthamoeba. Unworn lotrafilcon A contact lenses with (Focus Night & Day) and without surface treatment and Acuvue, conventional hydrogel lenses, were quartered before 90-min incubation with Acanthamoeba castellanii trophozoites. After incubation and rinsing, the trophozoites attached to one surface of each quarter were counted by direct light microscopy. Sixteen replicates were observed for each lens type. Logarithmic transformation of data allowed the use of parametric analysis of variance. No significant difference in attachment was established between the untreated lotrafilcon A and the conventional hydrogel lenses (P<0.001); however, surface treatment of the native Focus Night & Day material produced a significant increase in attachment (P<0.001). Commercially available Focus Night & Day lenses are subjected to a plasma surface treatment to reduce lens hydrophobicity; however, this procedure results in an enhanced acanthamoebal attachment. It is possible that the silicone hydrogel lens could be at a greater risk of promoting Acanthamoeba infection if exposed to the organism because of the enhanced attachment characteristic of this material. Eye care professionals should be aware of the enhanced affinity that Acanthamoeba show for this lens and accordingly emphasise to patients the significance of appropriate lens hygiene. This is particularly important where lenses are worn in a regime that could increase the chance of exposure to the organism, i.e., 6 nights/7 days extended wear or daily wear, where lenses will be stored in a lens case, or where lenses are worn when in contact with potentially contaminated water sources, i.e., swimming or showering.

Influence of lens material and intra-ocular pressure on the outcome of non-contact tonometry over soft contact lenses

To quantify the influence of soft lens rigidity and power on the difference between intraocular pressure values (DeltaIOP) obtained by non-contact tonometry through soft lenses in situ and over the cornea (IOP). Both eyes of 25 patients, attending for either routine contact lens check up, were fitted with a (I) low water content silicone hydrogel lenses of relatively high modulus of rigidity (modulus of rigidity 1.2MPa, Focus Night and Day, Cibavision) and (II) high water content daily disposable of relatively low modulus of rigidity (0.91MPa, Focus Dailies, Cibavision). IOP measurements were taken over the cornea and repeated over the lens after insertion. Lens powers ranged from -7.50D to +6.00D. ANOVA revealed DeltaIOP was associated with both lens power and material (p<0.05). Multiple linear regression revealed relationships between DeltaIOP (y) lens power (x(1)) and IOP (x(2)) as follows (I), right eyes, y = 0.899x(1) - 0.172x(2) + 5.659 (F = 15.615, r = 0.766, p < 0.001, n = 25) (I), left eyes, y = 0.993x(1) - 0.101x(2) + 4.694 (F = 23.368, r = 0.825, p < 0.001, n = 25) (II) right eyes, y = 0.399x(1) - 0.370x(2) + 6.595 (F = 11.804, r = 0.719, p < 0.001, n = 25) (II) left eyes, y = 0.561(1) - 0.225x(2) + 4.153 (F = 28.736, r = 0.723, p < 0.001, n = 25) DeltaIOP appears to be related to lens power, material and to a lesser extent IOP. Practitioners should derive their own empirical relationship between DeltaIOP, lens power and IOP for the specific types of soft lenses they commonly use. This would improve efficiency in the screening of IOP in more susceptible soft lens wearers.

Corneal shape changes induced by first and second generation silicone hydrogel contact lenses in daily wear

To compare the corneal topographical changes induced by two first and second generation silicone-hydrogel (SiH) contact lenses after 3 months of daily wear (DW). Prospective, consecutive case-series in which patients wore one of 3 different contact lenses (either the first generation SiH Focus Night & Day, the second generation SiH Acuvue Oasys or the monthly disposable Soflens 38 hydrogel lens as control group) on a DW basis for 3 months. Over-refraction, visual acuity, mean keratometry, corneal astigmatism, corneal eccentricity, superficial regularity and superficial asymmetry indices were monitored over the 3-month period. Nineteen eyes of 10 patients completed the study. Seven Focus Night & Day, 7 Acuvue Oasys and 5 Soflens 38 contact lenses were fitted. There were no significant changes between any of the parameters measured at the 3-month visit in any of the SiH groups (non-parametric Wilcoxon test, p>0.05). However, the control group (Soflens 38) showed statistically significant changes regarding mean keratometry, corneal astigmatism and corneal eccentricity (p<0.05). Three patients wearing the first generation SiH showed adverse events of different degree related to their high modulus of elasticity. After 3 months of DW, wearers of first and second generation SiH lenses showed greater corneal stability than hydrogel monthly disposable contact lenses users regarding commonly used topographic corneal shape indices. However, complications related to the mechanical properties of first generation SiH were seen in three patients in the follow-up time.

Short-Term Corneal Endothelial Response to Wear of Silicone-Hydrogel Contact Lenses in East Asian Eyes

To evaluate corneal endothelial bleb response to wear of silicone-hydrogel contact lenses in eyes of East Asian subjects. A total of 24 subjects of East Asian origin, attended 3 separate sessions for a prospective, single-centre, trial. The following contact lenses were used: ACUVUE ADVANCE with HYDRACLEAR (ADVANCE, -3 dioptres), ACUVUE OASYS with HYDRACLEAR Plus (OASYS, -3 dioptres), Focus NIGHT & DAY (NIGHT & DAY, -3 dioptres) and SofLens 38 (+3 dioptres). A modified Balaam's crossover design was used to randomize presentation of sessions and contact lenses within sessions. Session 1 was a comparison between OASYS and SofLens 38 under closed eye conditions, session 2 was a comparison between ADVANCE and NIGHT & DAY under open eye conditions, and session 3 was a comparison between OASYS and NIGHT & DAY worn under closed eye conditions. Corneal endothelial images were captured with the Topcon SP-3000P noncontact Specular Microscope before lens wear, after 20 mins of wear with lenses on and 5 and 10 mins later after lens removal. Blebs were manually identified on these digital images by a masked observer. The area of blebs and total area under consideration were derived using ImageNet software and used to calculate percentage area of blebs. A boundary of equivalence of 1% was used as a clinically significant bleb area difference, and two-sided 95% confidence intervals were utilized to evaluate differences between lenses within each session. In session 1, SofLens 38 produced a mean percentage area of blebs of 8.0% under closed eye conditions, which was significantly different to that produced by OASYS (1.6%). In session 2, both Advance and Night & Day produced a mean percentage bleb area of 0.4% under open eye conditions. In session 3, OASYS and NIGHT & DAY produced statistically similar mean percentage bleb areas of 1.7% and 2.0%, respectively. The similarity of bleb responses induced by the silicone-hydrogel lenses under the tested wearing conditions is consistent with the proposition that increases in Dk/t above a certain level will produce minimal change in corneal physiologic conditions compared with that when no lens is worn.

Clinical Study of Focus NIGHT &amp;DAY® contact lenses

Objectives: To investigate the visual and ocular implications of continuous wearing a silicon hydrogel contact lens for up to 3 weeks , in a dry semi-arid climate environment. Methods: Clinical examination of eye conditions (visual acuity, Schirmer test, corneal thickness and endothelial cells counts) for 9 healthy voluntary students was carried out between September and November of 2004 in Riyadh\'s King Saud University clinical facilities, using Ciba Vision\'s ocus Day & Night® lotrafilcon lenses. Which is measured weekly for 3 weeks. Results: Visual acuity testing revealed no significant changes after three weeks of continuous wear of the Focus lens. An average minimum angle of resolution (MAR) of 1.045 min arc was maintained throughout the 3 weeks. No significant drop had been recorded (p>0.05). The Schirmer test for eye lubrication showed an overall decrease in the wetting of the strip from about 36 mm to around 27 mm. Corneal thickness for the 9 subjects perior to CL wearing was 0.529 ± 0.050 mm, slightly increased to 0.533 ± 0.044 mm at the end of the study. The mean cell area value was 359 ± 67 Um2 at first visit, becoming only marginally higher at 361 ± 71 Um2 after three weeks of contact lens wear. Conclusion: The Focus NIGHT & DAY® lenses can be worn safely as extended-wear contact lenses for up to 3 weeks without ocular complications. Visual acuity, tear functions or corneal structure are not altered. Keywords: optometry, silicone hydrogel materials, resolution, ocular.Sudan Journal of Medical Sciences Vol. 3 (2) 2008: pp. 115-120

Effects of lotrafilcon A and omafilcon A bandage contact lenses on visual outcomes after photorefractive keratectomy

To evaluate postoperative healing between bandage contact lenses with high and low oxygen permeability in patients having photorefractive keratectomy (PRK). Center for Refractive Surgery, Walter Reed Army Medical Center, Washington, DC, USA. This retrospective study compared patients receiving a high-oxygen-transmission bandage contact lens (Focus Night & Day [N&D], Ciba Vision; n = 92) and those receiving a low-oxygen-transmission lens (Proclear, Cooper Vision; n = 114) after PRK. Visual outcomes, safety, and efficacy were assessed postoperatively at 1, 4, and 7 days and 1, 3, 6, and 12 months. Overall pain scores were higher in the Proclear group at 1 day (P = .000) and 4 days (P = .027). The N&D group had an increase in corneal infiltrates at 4 days (P = .025) and 1 week (P = .017). At 1 month, 40.4% of patients in the Proclear group and 18.6% in the N&D group had a 1 or more line decrease in best spectacle-corrected visual acuity (BSCVA) (P = .002). Although there was a trend toward a higher haze rate in the Proclear group, it was not statistically significant (P = .064). There was no statistically significant difference in uncorrected visual acuity, goal of emmetropia, contrast sensitivity, or reepithelialization. The N&D lens produced less pain and better postoperative results in terms of haze and BSCVA at 1 month. However, it led to a higher incidence of corneal infiltrates. There was no difference between the lenses in the end result at 12 months.

A Preliminary In Vivo Assessment of Higher-Order Aberrations Induced by a Silicone Hydrogel Monofocal Contact Lens

To evaluate the effect of negatively powered soft contact lenses on ocular higher-order aberrations (HOAs). HOA measurements were performed with fixed optical zones of 4.0 and 6.0 mm on 20 eyes of 10 participants before and minutes after wearing extended-wear Focus NIGHT & DAY contact lenses. For each eye, three contact lens powers were used: -2.00 diopters (D), -4.00 D, and a power equal to the spherical equivalent of each eye. The change in spherical aberration was highly correlated with the change in negative power of the contact lens at an optical zone of 4 and 6 mm (Pearson correlation coefficient=0.914 and 0.743, respectively, P<0.0001). Total HOAs had a weaker but important correlation at an optical zone of 6 mm (Pearson correlation coefficient=0.470, P=0.037) and insignificant correlation at an optical zone of 4 mm. Coma and trefoil were poorly correlated with contact lens power in either optical zone. Compared to the control using both optical zones, the -2.00 D contact lens resulted in a significant increase in total HOAs and spherical aberration, whereas the -6.00 D lens yielded a marked decrease in spherical aberration and a mild, statistically insignificant increase in total HOAs. Both contact lens powers yielded larger ocular coma and unchanged trefoil levels. The change from induction to reduction of spherical aberration occurred at -4.00 D. The Focus NIGHT & DAY lens vehicle harbors positive spherical aberration and coma, independently of the lens power. The negative power of contact lenses induces negative spherical aberration, which, at large values, compensates for the lens vehicle positive spherical aberration to produce a net negative spherical aberration.

Clinical Evaluation of Silicone Hydrogel Lens Wear With a New Multipurpose Disinfection Care Product

To evaluate subjective symptoms and clinical signs in silicone hydrogel contact lens wearers with three different multipurpose solution (MPS) lens care regimens. In a double-masked, randomized, concurrently controlled study, 233 subjects from 12 clinical sites wore one of two silicone hydrogel lens brands (ACUVUE Advance or Focus NIGHT & DAY) for 1 month on a daily-wear basis supported by a new reconditioning multipurpose disinfecting solution (MPDS) preserved with POLYQUAD and ALDOX, regimen 1 (OPTI-FREE RepleniSH Multi-Purpose Disinfecting Solution), or by one of two MPSs preserved with polyhexamethyl biguanide, regimen 2 (ReNu MultiPlus Multi-Purpose Solution No Rub Formula) or regimen 3 (Complete MoisturePLUS Multi-Purpose Solution). Significant differences in favor of regimen 1 were found in subjective responses of subjects wearing ACUVUE Advance lenses. For Focus NIGHT & DAY lens wearers, regimen 1 was associated with significantly less corneal staining (severity [P=0.0019], area [P=0.0077]) than regimen 2 was. The average number of times per day that rewetting drops were used was significantly higher for subjects randomized to regimen 3 than for subjects using regimen 1. The clinical performance of the new MPDS product with silicone hydrogel lenses was generally as good as or better than the two comparative polyhexamethyl biguanide-preserved MPSs. Clinical differences were evident between the products. Practitioners should be aware that MPS product choice for use with silicone hydrogel lenses may lead to different clinical outcomes, particularly in regard to stress on the ocular surface, as evidenced by the corneal staining response.

Extraction Efficiency of an Extraction Buffer Used to Quantify Lysozyme Deposition on Conventional and Silicone Hydrogel Contact Lens Materials

Extracting lysozyme from Food and Drug Administration group IV etafilcon lenses by using 0.2% trifluoroacetic acid and acetonitrile (TFA/ACN) is a well-established procedure. TFA/ACN has been the extraction buffer of choice for extracting proteins from silicone hydrogel contact lenses. The purpose of this study was to determine the efficiency of TFA/ACN in extracting lysozyme from silicone hydrogel and etafilcon lenses by using an in vitro model. ACUVUE 2, Focus NIGHT & DAY, O2 Optix, PureVision, and ACUVUE Advance lenses were incubated in simple lysozyme solution and a complex artificial tear solution consisting of multiple tear components containing lysozyme labeled with iodine 125. All the silicone hydrogel lenses were incubated for 28 days, whereas the ACUVUE 2 lenses were incubated for 7 days at 37 degrees C with constant rotation. After the incubation period, radioactive counts were determined, and the lenses were placed in an appropriate volume of the buffer for 24 hours in darkness. The lenses were removed from the buffer, and radioactive counts were determined again. Extraction efficiencies for lysozyme from the artificial tear solution were 97.2% +/- 1.2% for ACUVUE 2, 64.3% +/- 6.2% for Focus NIGHT & DAY, 62.5% +/- 5.6% for O2 Optix, 53.5% +/- 5.8% for PureVision, and 89.2% +/- 3.4% for ACUVUE Advance. Results were similar for the lysozyme extracted after incubating in the simple lysozyme solution. TFA/ACN is extremely efficient at extracting lysozyme deposited on etafilcon lenses. However, it does not extract all the lysozyme deposited on silicone hydrogel lenses, and alternative extraction procedures should be sought.

In vitro water wettability of silicone hydrogel contact lenses determined using the sessile drop and captive bubble techniques

This study investigated the water contact angles of five commercially available silicone hydrogel contact lenses (Acuvue Advance, Acuvue Oasys, Focus Night & Day, O2 Optix, and PureVision) using sessile drop and captive bubble techniques. The only lens type that showed a significant difference in water contact angle when measured by sessile drop direct from the blister compared with after 48 h of soaking/washing in saline was the Acuvue Advance lens (from 66 degrees to 96 degrees, respectively) (p=0.0002), presumably because of surface active agents within the blister solution. The water contact angle data split the lenses into two distinct groups (p<or=0.002). The Acuvue Advance, Acuvue Oasys, and PureVision lenses demonstrated relatively high sessile drop measures and relatively low captive bubble values (thereby displaying significant hysteresis) whereas the Focus Night & Day and O2 Optix lenses showed relatively low sessile drop measures and relatively high captive bubble values (with little hysteresis). Contact angle analysis of hydrogel lens surfaces is highly methodologically dependent and may be able to predict the clinical performance of contact lenses in vivo.

Quantity and Conformation of Lysozyme Deposited on Conventional and Silicone Hydrogel Contact Lens Materials Using an In Vitro Model

To determine the activity of hen egg lysozyme (HEL) deposited on conventional and silicone hydrogel contact lens materials by using an in vitro model. ACUVUE 2 (etafilcon A), PureVision (balafilcon A), ACUVUE Advance (galyfilcon A), Focus NIGHT & DAY (lotrafilcon A), O2 Optix (lotrafilcon B), Proclear (omafilcon A), and ACUVUE OASYS (senofilcon A) contact lenses were deposited in vitro in a phosphate-buffered solution (PBS) containing 2 mg/mL HEL. Lenses were briefly rinsed in PBS to remove unbound material and extracted in a mixture of acetonitrile and trifluoroacetic acid. After lyophilization, extracts were examined for lysozyme activity by micrococcal assay and total protein by Western blot. In terms of total protein accumulation, ACUVUE 2 showed the most, with 1,800 microg per lens. Proclear was next, with 68 microg per lens, and Focus NIGHT & DAY showed the least, with 2 microg per lens. ACUVUE Advance, ACUVUE OASYS, and O2 Optix accumulated similar amounts of lysozyme, at approximately 6 microg per lens. Lysozyme deposited on ACUVUE 2 showed the greatest activity (91% +/- 5%), and this result was statistically different from all other lens types (P<0.001). Lysozyme deposited on Focus NIGHT & DAY (24% +/- 5%) and O2 Optix (23% +/- 11%) showed the lowest activity. Lysozyme deposits on other lens materials showed intermediate activity (ACUVUE Advance, 60% +/- 15%; ACUVUE OASYS, 51% +/- 9%; PureVision, 58% +/- 8%; and Proclear, 38% +/- 3%). Silicone hydrogel lenses acquire less lysozyme deposit than conventional group II (Proclear) or group IV (ACUVUE 2) lenses do, and the levels of activity of the lysozyme are highly variable between materials.

Extended-Wear Silicone Hydrogel Soft Contact Lenses in the Management of Moderate to Severe Dry Eye Signs and Symptoms Secondary to Graft-Versus-Host Disease

To determine the safety and efficacy of the Focus NIGHT & DAY (CIBA Vision, Duluth, GA) silicone hydrogel contact lens in the management of refractory, moderate to severe dry eye signs and symptoms secondary to graft-versus-host disease (GVHD). Seven patients with GVHD and moderate to severe dry eye disease as determined by the Ocular Surface Disease Index (OSDI) questionnaire were fitted with a near plano Focus NIGHT & DAY soft contact lens (SCL) used on a 7-night continuous-wear basis. Visual acuity, objective measures of dry eye disease (i.e., Schirmer I, tear breakup time, and corneal fluorescein staining), and OSDI scores were compared before SCL wear and after 1 week and 1 month of SCL wear. There was significant improvement in subjective assessment of dry eye symptoms (initial vs. 1-month OSDI score, 76.8 +/- 13.6 vs. 31.2 +/- 17.8, P<0.0005, paired t test). In addition, patients had significant improvement in best-corrected visual acuity after 1 month of SCL wear (initial vs. 1-month logMAR visual acuity for the right eye, 0.23 +/- 0.050 vs. 0.04 +/- 0.027, P<0.007; initial vs. 1-month logMAR visual acuity for the left eye, 0.22 +/- 0.049 vs. 0.04 +/- 0.020, P<0.007, analysis of variance, Dunnett post hoc). There were no significant changes in results of Schirmer I testing, corneal fluorescein staining, or tear breakup time. No adverse events or complications of SCL wear were observed. The Focus NIGHT & DAY contact lens can improve subjective dry eye symptoms and visual acuity in patients with refractory dry eye disease secondary to GVHD.

Objective and Subjective Responses in Patients Refitted to Daily-Wear Silicone Hydrogel Contact Lenses

Silicone hydrogel (SiH) lenses offer many physiological advantages for daily wear (DW) in addition to the continuous-wear modality for which they were originally developed. The purpose of this study was to investigate the clinical performance and physiological responses in a group of successful long-term wearers of conventional hydrogel lenses when refitted with DW SiH contact lenses. Eighty-seven successful soft lens wearers (8.4+/-4.7 years of prior lens wear) participated in this study. Bulbar and limbal hyperemia were subjectively graded and digitally photographed for subsequent masked objective evaluation. Subjective symptoms were scored using visual analog scales. In addition, refractive error, corneal curvature, and corneal thickness were measured. All subjects were refitted with Focus Night & Day (lotrafilcon A) SiH lenses; however, to reduce the potential for bias, they were informed that they were being randomly assigned to wear either low oxygen permeability (Dk) lenses or high Dk SiH lenses and were "masked" as to their lens assignment. Subjects returned after 1 week, 1 month, and 2 months of DW, at which time all gradings, photographs, and measurements were repeated. End-of-day subjective symptoms were also graded periodically during the study. Ninety-three percent of subjects were successfully refitted. Both objective and subjective evaluations showed that bulbar and limbal hyperemia decreased significantly in all quadrants during the study (p<0.001), particularly for those subjects with greater baseline hyperemia (p<0.001). Subjects reported a concurrent reduction in end-of-day dryness and improved end-of-day comfort compared with their habitual lenses (p<0.001). No significant changes in refractive error, tarsal papillary response, corneal curvature, or corneal thickness were found during the study. Hyperemia in contact lens wearers may be attributed to a number of factors, including hypoxia. Refitting existing low Dk lens wearers with SiH lenses on a DW basis can result in a decrease in hyperemia, which may be significant for some subjects and also results in improvements in symptoms of dryness and discomfort.

Comparison of Conventional and Silicone Hydrogel Contact Lenses for Bullous Keratoplasty

To compare the efficacy and safety of conventional lenses and silicone hydrogel lenses in the treatment of bullous keratopathy. The silicone hydrogel bandage contact lenses used were Focus NIGHT & DAY and PureVision. The conventional lens used was Sauflon 85%. This was a prospective, comparative study of 22 patients with painful bullous keratopathy in one eye. Patients visited a specialty contact lens department and were fitted with all three different lens types in their affected eye for 1 month each, for a total duration of 3 months. The main outcome measures were comfort and pain relief, which patients scored on a scale that ranged from 1 to 5, with 1 being very poor and 5 being excellent. Doctors assessed the fit of the lens, its movement, and any deposit buildup. The statistical tests applied were the Kruskal-Wallis test and the Mann-Whitney test. Sixteen of the 22 patients (24 eyes) successfully completed 1 month's wear of all three bandage contact lenses. The median comfort score was 3.9 for PureVision, 3.8 for Focus NIGHT & DAY, and 2.8 for Sauflon 85%; there was a statistical significance among the three groups (P=0.031). Silicone hydrogel lenses performed better than conventional lenses for comfort. The Mann-Whitney test showed that there was no statistically significant difference for comfort scores of Focus NIGHT & DAY versus PureVision (P<0.782) or of Focus NIGHT & DAY versus Sauflon 85% (P<0.073). However, there was a statistically significant difference for comfort scores of PureVision versus Sauflon 85% (P<0.0136). The median pain relief score was 3.8 for PureVision, 3.7 for Focus NIGHT & DAY, and 3.2 for Sauflon 85%. There was no significant difference among the three lenses for pain relief score. All three lens types were similarly good with regard to contact lens fit, movement, and deposit buildup. The use of silicone hydrogel lenses are a safe and effective alternative to conventional contact lenses for the treatment of bullous keratopathy.

Therapeutic Use of Silicone Hydrogel Contact Lenses in Children

To evaluate the safety and efficacy of silicone hydrogel extended-wear contact lenses when used for therapeutic purposes for children. This was a prospective open-ended nonrandomized study. Twenty-nine consecutive pediatric patients at the Eye Clinic of Kaunas University of Medicine in Lithuania requiring therapeutic contact lens wear for anterior segment disorders were enrolled. In all cases, Focus NIGHT & DAY (CIBA Vision, Duluth, GA) contact lenses were used. Success or failure of specific treatment and the presence of ocular or lens-related complications were noted in each case. Twenty-nine eyes were fitted with Focus NIGHT & DAY contact lenses. The average age at the time of presentation was 9 years (range, 2 months to 17 years). The conditions treated were burn (seven eyes), corneal erosion (three eyes), neurotrophic keratitis (four eyes), descemetocele (one eye), corneal ulcer (one eye), keratouveitis (one eye), exposure keratitis (one eye), vernal keratoconjunctivitis (one eye), herpetic keratitis (one eye), corneal perforation (two eyes), and corneal injury (seven eyes). The mean duration of continuous contact lens wear was 17.8 days (range, 1-131 days). Dry eye was the cause of contact lens loss in one eye. Total bandage contact lens wear was effective in 27 (93%) eyes. Complications related to contact lens wear were limited to one case (increased signs of inflammation in the case of herpetic keratitis) requiring cessation of therapeutic lens wear after 24 hours. Focus NIGHT & DAY silicone hydrogel contact lenses were found to be safe and efficacious for continuous-wear therapeutic use for children.

The Clinical Performance of a Silicone Hydrogel Lens for Daily Wear in an Asian Population

To evaluate slitlamp findings, frequency and severity of symptoms, and wearing time with a silicone hydrogel contact lens when used for daily wear by patients of Asian ethnicity. This was a five-site, 88-patient, prospective, open-label study involving 1 month of daily wear of lotrafilcon A lenses (Focus NIGHT & DAY, CIBA Vision, Duluth, GA) among adapted soft lens wearers previously wearing etafilcon A (ACUVUE 2, Johnson & Johnson Vision Care, Jacksonville, FL) or polymacon (Optima FW, Bausch & Lomb, Rochester, NY) lenses. Statistically significant improvements in conjunctival redness, limbal redness, and corneal neovascularization were reported after 1 week and 1 month of wear. Patients reported statistically significant improvements in subjective symptoms of redness, dryness during the day, and dryness at the end of the day. More patients reported increased than reduced average daily wear time and average daily comfortable wear time with the silicone hydrogel lens. Significant improvements in clinical signs and subjective symptoms may occur when some patients of Asian ethnicity wearing conventional hydrogel lenses for daily wear are refitted with silicone hydrogel lenses for daily wear.

Efficacy of multipurpose solutions against Acanthamoeba species

Aim The disinfection efficacy of contact lens multipurpose solutions (MPSs) against Acanthamoeba polyphaga (Ros) and Acanthamoeba castellanii (ATCC30868) cysts and trophozoites was determined by both biocidal and manufacturer-recommended no-rub/rinse regimen testing. Methods A biocidal assay using four MPSs (ReNu ® with MoistureLoc ®, Opti-free Express, Solo-care Plus, and Complete MoisturePlus) was conducted with or without the presence of organic soil. A second test procedure compared the ability of five MPSs (ReNu with MoistureLoc MPS, ReNu MultiPlus, Opti-free Express, Solo-care Aqua, and Complete MoisturePlus) to remove and kill Acanthamoeba species cysts and trophozoites from SofLens 38 and Surevue conventional hydrogel lenses, and Focus Night & Day silicone hydrogel lenses using the manufacturer-recommended regimen. Results In the biocidal assay, only ReNu with MoistureLoc successfully killed both trophozoites and cysts (>3 log) within the manufacturer-recommended soak time. A >3 log decrease in trophozoites, but not cysts, was reported for Opti-free Express; however, Solo-care Plus and Complete MoisturePlus did not reduce the number of cysts or trophozoites by >3 log during the manufacturer-recommended soak time. In the no-rub/rinse regimen tests, only ReNu with MoistureLoc removed an inoculum of 2 × 10 5 trophozoites or cysts from SofLens 38 and Surevue hydrogel lenses, as well as Focus Night & Day silicone hydrogel lenses. Less than 10 viable organisms were recovered from the lenses after the 10 s rinse and 4 h soak. Opti-free Express, Solo-care Aqua, and ReNu MultiPlus were effective at removing trophozoites and cysts from SofLens 38 and Surevue conventional hydrogel lenses, but not from Focus Night & Day silicone hydrogel lenses. In excess of 10 viable organisms were recovered from all lenses after the manufacturer-recommended regimen using Complete MoisturePlus. Conclusions These data suggest that some MPSs, when used as recommended by the manufacturer, are more effective at killing representative strains of Acanthamoeba than others.

Effect of Artificial Tears on Visual Performance in Subjects With Dry Eye

Disruption of the anterior refracting surface of the eye (i.e., the tear layer) reduces visual performance. Tear layer breakup occurs soon after a blink in contact lens wearers and patients with dry eye. This study determined whether artificial tears stabilize the tear film and improve visual performance in contact lens wearers who also exhibit a dry eye. Five subjects with mild to moderate dry eye (probably as a result of an evaporative dry eye) during spectacle and contact lens wear were fitted with a Focus Night & Day hydrogel lens for this study. A temporal, two-alternative, forced-choice paradigm was used to measure contrast sensitivity. The stimuli were vertically oriented sine wave gratings (between 0.5 and 14 cpd) presented for 16.67 msec. The stimuli were presented at two different times after blink detection: 2 sec after blink detection (i.e., before tear layer breakup) or 4 sec after tear film breakup. Four conditions were investigated at 4 sec after tear layer breakup: 1) without artificial tears added, 2) with Clerz2 (Alcon, Fort Worth, TX) instilled, 3) with Sensitive Eyes (Bausch & Lomb, Rochester, NY), and 4) with GenTeal (Novartis, Basel, Switzerland) applied. The artificial tears were instilled at 10-min intervals during the data collection. The short-term visual effects of drop instillation were also investigated by continually monitoring contrast sensitivity for a 14-cpd grating after a single-drop administration. High spatial frequency contrast sensitivity and visual acuity were found to be reduced after tear film breakup in the absence of supplementation with artificial tears. For the group data (and four of five subjects), the instillation of Sensitive Eyes improved the contrast sensitivity and visual acuity to the level attained before tear breakup, thus prolonging visual performance. Clerz2 and GenTeal did not produce any enhancement in visual performance. A short-term decrease in contrast sensitivity was also observed with a single administration of Clerz2 and GenTeal. This study indicates that there was a benefit of Bausch & Lomb Sensitive Eyes tear supplementation on visual performance in subjects with an evaporative dry eye. This may be the result of 1) aqueous supplementation in these subjects and/or 2) the minimal tear layer disruption found with Sensitive Eyes drop administration. The results suggest that practitioners need to identify those patients who can benefit from the use of appropriate artificial tear supplements.