Observation and assessment of the immediate use of a silicon hydrogel contact lens after transepithelial corneal cross linking: a prospective study.
BMC ophthalmology
BACKGROUND:Transepithelial corneal crosslinking (CXL) is a novel surgical approach for the treatment of keratoconus, which is a bilateral asymmetrical ophthalmological disease accompanied by progressive corneal ectasia. Silicon hydrogel (SiH) contact lenses have been extensively used in clinical ophthalmologic medicine, as a postoperative ophthalmological intervention. However, the ideal lens application duration after transepithelial CXL remains uncertain. Here, we aimed to investigate the effects and comfort of immediate corneal contact lens use after transepithelial CXL for keratoconus. METHODS:In this prospective study, 60 patients with keratoconus who underwent transepithelial CXL treatment were enrolled from September 2021 to January 2023 with a male:female ratio of 39:21, and an average age of 25.42 ± 5.47 years. The patients were divided randomly into two groups: group A contained 30 patients wearing silicone hydrogel contact lenses for 7 days postoperatively, and group B contained 30 patients wearing the same contact lenses for 3 days. Ten subjective ophthalmologic symptoms were surveyed by the patients, including pain, photophobia, foreign body sensation, tearing, burning, blurred vision, dry eyes, difficulty opening the eyes, astringency, and stinging. Ophthalmologic signs, including corneal edema and conjunctival congestion, were recorded by a single clinician on postoperative days 1, 3, and 7. RESULTS:Each surgical procedure was readily performed without complications, and both groups postoperative day 7 (P = 0.04), where group B scored (0.01 ± 0.41) lesser than group A (0.12 ± 0.29), whilst corneal edema in both groups recorded significantly different on postoperative days 5 and 7 (group A demonstrated the result of 0.17 ± 0.14 and 0.08 ± 0.11 for the respective days, whereas group B indicated 0.10 ± 0.13 and 0.03 ± 0.07 at the corresponding times). CONCLUSIONS:Immediate use of silicone hydrogel corneal lenses after transepithelial CXL effectively alleviates postoperative ocular distress, particularly with a three-day use period as the ideal duration.
10.1186/s12886-023-03217-4
Effects of senofilcon A and lotrafilcon B bandage contact lenses on epithelial healing and pain management after bilateral photorefractive keratectomy.
Duru Zeynep,Duru Necati,Ulusoy Döndü Melek
Contact lens & anterior eye : the journal of the British Contact Lens Association
PURPOSE:The purpose of this study was to compare postoperative epithelial healing time and ocular discomfort score in patients wearing two types of silicon hydrogel bandage contact lenses (BCLs) following bilateral photorefractive keratectomy (PRK). METHODS:For the study's contralateral eye comparison, 43 patients who underwent bilateral PRK were randomized to be fitted for a senofilcon a lens in one eye and a lotrafilcon B lens in the other. The patients were masked to the specific BCL in each eye. On the first 3 days after PRK, the epithelial defect size was calculated, and patients reported their level of ocular discomfort, including pain, epiphora, and photophobia, on a visual analog scale (0 = no pain or discomfort, 10 = highest level of pain and discomfort). RESULTS:Epithelial defect size (mm) did not differ significantly between the BCLs on Day 1 (senofilcon A vs. lotrafilcon B: 14.15 ± 5.59 vs. 14.93 ± 5.72, p = .327), Day 2 (senofilcon A vs. lotrafilcon B: 7.43 ± 4.67 vs. 7.04 ± 3.82, p = .586), or Day 3 (senofilcon A vs. lotrafilcon B: 0.59 ± 1.44 vs. 0.38 ± 1.08, p = .348) postoperation. By Day 3, re-epithelialization was complete in 35 eyes (81.3%) with senofilcon A lenses and 36 eyes (83.7%) with lotrafilcon B lenses. Patients reported less pain in eyes with senofilcon A lenses during the first 3 days postoperation (for all, p < .001) and less epiphora during the first 2 days postoperation (Day 1: p = .008, Day 2: p < .001, Day 3: p = .267) than in eyes with lotrafilcon B lenses. No significant difference in photophobia emerged between the BCLs postoperatively (for all, p > .05). CONCLUSIONS:Although duration of corneal re-epithelialization after PRK between the two BCLs did not differ significantly, senofilcon A lenses caused significantly less pain and epiphora after PRK.
10.1016/j.clae.2019.08.008
Evaluation of Adherence to Contact Lens Materials.
Microorganisms
Bacterial keratitis is a risk associated with the use of contact lenses for cosmetic purposes or vision correction. In this in vitro experimental study, we examined the ability of the ocular pathogen to adhere to monthly or biweekly replacement contact lenses. We performed quantitative adhesion assays to evaluate the adherence of to seven contact lens materials: comfilcon A, senofilcon A, omafilcon B, fanfilcon A, balafilcon A, senofilcon C, and lehfilcon A. Lehfilcon A is a newly marketed silicon hydrogel contact lens with a surface modification of poly-(2-methacryloyloxyethyl phosphorylcholine) (PMPC). PMPC has previously been demonstrated to be an effective anti-biofouling treatment for numerous surfaces. We observed low adherence to lehfilcon A compared to other materials. We demonstrate the use of the fluorescent dye 5(6)-Carboxytetramethylrhodamine succinimidyl ester to covalently stain live cells prior to material adhesion studies.
10.3390/microorganisms11010217
Recent Applications of Contact Lenses for Bacterial Corneal Keratitis Therapeutics: A Review.
Pharmaceutics
Corneal keratitis is a common but severe infectious disease; without immediate and efficient treatment, it can lead to vision loss within a few days. With the development of antibiotic resistance, novel approaches have been developed to combat corneal keratitis. Contact lenses were initially developed to correct vision. Although silicon hydrogel-based contact lenses protect the cornea from hypoxic stress from overnight wear, wearing contact lenses was reported as an essential cause of corneal keratitis. With the development of technology, contact lenses are integrated with advanced functions, and functionalized contact lenses are used for killing bacteria and preventing infectious corneal keratitis. In this review, we aim to examine the current applications of contact lenses for anti-corneal keratitis.
10.3390/pharmaceutics14122635
Chromatic dispersion of soft contact lens materials.
Contact lens & anterior eye : the journal of the British Contact Lens Association
PURPOSE:To investigate and evaluate the chromatic dispersion of various hydrogel and silicon hydrogel contact lens materials. METHODS:Eighteen different soft contact lens materials with high and low water content in lens power of -1.00 DS were measured by one operator at temperature of 20 °C ± 0.5° soaked in ISO standard phosphate-buffered saline (PBS) and in their respective packaging solutions (PS). An analogue Abbe refractometer (Model Zuzi 320, AUXILAB, S.L., Navarra, Spain) was used for refractive index (RI) measurements at 5 different wavelengths. All contact lenses were presented in a random and masked order to the operator. The Bland-Altman method with 95 % limits of agreement (LoA) and coefficient of repeatability (CoR) was used to characterise the repeatability of refractive index measurements. The Abbe numbers for each material were calculated by entering the measured and interpolated refractive indices into the Abbe number equation. One-way ANOVA analysis was used to test if there were significant differences between the 5 different wavelengths (470 nm-680 nm) within each material. An unpaired t-test was used to determine if there were differences in refractive index or dispersion between packaging solution and PBS results. RESULTS:Nelfilcon A (Dailies Aqua Comfort Plus) soaked in PS showed the best repeatability of all 18 examined soft contact lenses across all wavelengths with an average refractive index of 1.3848 for all 6 contact lenses with a standard deviation of 0.00064. The 95 % limits of agreement were between 1.3835 and 1.3860. The mean coefficient of repeatability for nelfilcon A was 0.00125. For contact lenses soaked in ISO Standard PBS comfilcon A (Biofinity) had the best repeatability. The average refractive index of all 6 contact lenses was 1.4041 with a standard deviation of 0.00031 and a coefficient of repeatability of 0.00060. The 95 % limits of agreement were between 1.4035 and 1.4047. The analysis with One-way ANOVA with multiple comparisons involving Holm-Sidak post-hoc, showed that there are significant differences (p < 0.001, F = 376.2 between wavelengths and F = 1559 between different refractive indices) in the refractive index of most common lens materials across the visible wavelength range. Based on unpaired t-test, there is no significant difference (p > 0.05) in the Abbe numbers of the tested lens materials whether they have been placed in the packaging solution or in standard PBS (p > 0.05, 95 % CI = -4.8070 to 5.8680, t = 0.2054). The Abbe numbers for the calculated contact lenses soaked in PS ranged between 43.7 and 89.9. For contact lenses stored in PBS the range was between 46.3 and 81.6. CONCLUSION:There is a good repeatability between repeated RI measurements taken from the same lens and from the same material. The significant differences between the refractive indices across the 5 different wavelengths showed the presence of chromatic dispersion in the 18 evaluated soft contact lens materials. Furthermore, it could be shown that there is no significant difference in dispersion whether the contact lenses are soaked in standard PBS or in their respective packaging solutions. With no other published data available as a reference, absolute accuracy of the calculated Abbe numbers remains to be confirmed, however, this study did confirm that significant chromatic dispersion exists in soft contact lens materials.
10.1016/j.clae.2023.101864
Silicone hydrogel versus hydrogel soft contact lenses for differences in patient-reported eye comfort and safety.
The Cochrane database of systematic reviews
BACKGROUND:Ocular discomfort is the leading cause of permanent discontinuation of soft contact lens (SCL) wear. Silicone hydrogel and hydrogel materials are the two major categories of SCLs, with silicone hydrogel materials being newer and more breathable than hydrogel materials. Whether comfort is associated with SCL material is controversial despite numerous studies. Similarly, the difference between these materials in terms of safety outcomes (e.g. frequency of microbial keratitis) is unclear. OBJECTIVES:To evaluate the comparative effectiveness and safety of silicone hydrogel compared with hydrogel SCLs on self-reported comfort, dry eye test results, and adverse events in SCL-wearing adults 18 years of age or older. SEARCH METHODS:The Cochrane Eyes and Vision Information Specialist searched the electronic databases for randomized controlled trials (RCTs). There were no restrictions on language or date of publication. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, including the Cochrane Eyes and Vision Trials Register; 2022, Issue 6), MEDLINE Ovid, Embase.com, PubMed, LILACS (Latin American and Caribbean Health Science Information database), ClinicalTrials.gov, and World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We also searched the reference lists of identified studies, review articles, and guidelines for information about relevant studies that may not have been identified by our search strategy. Furthermore, we contacted investigators regarding ongoing trials. The most recent database search was conducted on 24 June 2022. SELECTION CRITERIA:Our search selection criteria included RCTs, quasi-RCTs, and cross-over RCTs. DATA COLLECTION AND ANALYSIS:We applied standard Cochrane methodology. MAIN RESULTS:We included seven parallel-group RCTs conducted in the USA, the UK, Australia, Germany, India, and Turkey. A total of 1371 participants were randomized. The duration of SCL wear ranged from one to 52 weeks. Study characteristics and risk of bias The median number of participants per trial was 120 (interquartile range: 51 to 314), and the average age ranged from 20.7 to 33.0 years. Women represented the majority of participants (range 55% to 74.9%; 5 RCTs). Collectively, the included trials compared eight different silicone hydrogel SCLs with three different hydrogel SCLs. Five trials compared daily disposable SCLs, and two compared extended wear SCLs (worn for seven days and six nights). New SCL wearers were enrolled in three trials. Two trials included both new and established SCL wearers, and two trials did not report participants' history of SCL use. Five trials were sponsored by industry. We judged the overall risk of bias to be 'high' or 'some concerns' for the safety and efficacy outcomes. Findings One trial reported Ocular Surface Disease Index (OSDI) results, with the evidence being very uncertain about the effects of SCL material on OSDI scores (mean difference -1.20, 95% confidence interval [CI] -10.49 to 8.09; 1 RCT, 47 participants; very low certainty evidence). Three trials reported visual analog scale comfort score results, with no clear difference in comfort between materials, but the evidence was of very low certainty; trial results could not be combined because the three trials reported results at different time points. The evidence is very uncertain about the effect of SCL material on discontinuation of contact lens wear (risk ratio [RR] 0.64, 95% CI 0.11 to 3.74; 1 RCT, 248 participants). None of the included trials reported Contact Lens Dry Eye Questionnaire (CLDEQ-8) or Standard Patient Evaluation of Eye Dryness (SPEED) scores. There was no evidence of a clinically meaningful difference (> 0.5 unit) between daily disposable silicone hydrogel and hydrogel SCLs in corneal staining, conjunctival staining, or conjunctival redness (very low certainty evidence). Adverse events Very low certainty evidence from two trials comparing daily disposable SCLs suggested no evidence of a difference between lens materials in the risk of vision-threatening adverse events at one to four weeks (RR 0.68, 95% CI 0.08 to 5.51; 2 RCTs, 368 participants). Two trials comparing extended wear SCLs indicated that hydrogel SCLs may have a 2.03 times lower risk of adverse events at 52 weeks compared with silicone hydrogel SCLs (RR 2.03, 95% CI 1.38 to 2.99; 815 participants), but the certainty of evidence was very low. AUTHORS' CONCLUSIONS:The overall evidence for a difference between all included silicone hydrogel and hydrogel SCLs was of very low certainty, with most trials at high overall risk of bias. The majority of studies did not assess comfort using a validated instrument. There was insufficient evidence to support recommending one SCL material over the other. For extended wear, hydrogel SCL may have a lower risk of adverse events at 52 weeks compared to silicon hydrogel. Future well-designed trials are needed to generate high certainty evidence to further clarify differences in SCL material comfort and safety.
10.1002/14651858.CD014791.pub2