Efficacy and safety of a 3-month loteprednol etabonate 0.5% gel taper for routine prophylaxis after photorefractive keratectomy compared to a 3-month prednisolone acetate 1% and fluorometholone 0.1% taper

Changes in Posterior Cornea and Posterior-To-Anterior Curvature Radii Ratio 1 Year After LASIK, PRK, and SMILE Treatment of Myopia

PURPOSE

The purpose of this study was to compare changes in the posterior curvature and the posterior-anterior radii ratio of the cornea, 1 year postoperatively in laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), and small incision lenticule extraction (SMILE).

METHODS

This retrospective study was performed at a single surgical center. 199 eyes were included in the study from 119 patients with manifest refraction spherical equivalents from -7.61 to -2.54 D. 67 eyes underwent LASIK, 89 underwent PRK, and 43 underwent SMILE. Both preoperative and 1-year postoperative front and back sagittal keratometry were measured at 4- to 6-mm zones around the corneal vertex. Corneal asphericity (Q-value) was measured at an 8-mm zone around the corneal vertex.

RESULTS

The average change in the posterior-anterior radii ratio after LASIK, PRK, and SMILE did not differ between surgery groups at 4 mm (LASIK: -0.075, PRK: -0.073, SMILE: -0.072, P = 0.720), 5 mm (LASIK: -0.072, PRK: -0.068, SMILE: -0.068, P = 0.531), or 6 mm (LASIK: -0.075, PRK: -0.071, SMILE: -0.072, P = 0.456) zones. Anterior Q-value significantly positively increased after all 3 surgeries ( P < 0.001). The posterior Q-value also significantly positively increased after LASIK ( P < 0.001) and SMILE ( P < 0.001), but not after PRK ( P = 0.227). Both anterior and posterior keratometric power decreased significantly after LASIK, PRK, and SMILE for all diameters.

CONCLUSIONS

The change in the posterior-anterior radii ratio was not influenced by the type of refractive surgery performed, as indicated by statistically identical preoperative, postoperative, and delta values. In addition, the posterior cornea exhibited paracentral flattening after LASIK, SMILE, and PRK and increased oblateness after LASIK and SMILE.

Intensive topical steroid regimen for enhanced very early recovery after small incision lenticule extraction

OBJECTIVE

This study aims to investigate the topical steroid regimen after small incision lenticule extraction (SMILE) for its effect on very early restoration of visual quality.

METHODS

A total of 180 patients (360 eyes) who underwent SMILE were enrolled. These patients were randomly assigned to three groups, with 60 patients in each group. The only difference among these three groups was the administration of 0.1% fluorometholone (FML) eye drops within two hours after SMILE: no FML in group A, 0.1% FML once every hour in group B and 0.1% FML once every half hour in group C. The corrected distance visual acuity (CDVA), objective scattering index (OSI), modulation transfer function (MTF) cut-off, Strehl ratio (SR) and incidence of subjective symptoms were evaluated preoperatively, at 2, 4 and 24 h and one week after SMILE.

RESULTS

The CDVA, MTF cut-off and SR values were significantly higher in group C, when compared to the other two groups, at 2 and 4 h after SMILE (p < 0.05). Furthermore, the OSI and incidence of subjective symptoms were significantly lower in group C, when compared to the other two groups, at 2 and 4 h after SMILE (p < 0.05). However, no significant differences in CDVA, MTF cut-off, SR, OSI and the incidence of subjective symptoms were detected among the three groups at 24 h and one week after SMILE (p > 0.05).

CONCLUSION

The administration of 0.1% FML eye drops every half hour within two hours after SMILE accelerates the restoration of visual and optical quality, and reduces the incidence of subjective symptoms during the very early phase after surgery.

Influence of Preoperative Parameters on the Ratio of Keratometric Change per Diopter of Attempted Spherical Equivalent (∆K/∆SEQ) for Myopic Correction Within LASIK, PRK, and SMILE

Purpose

To compare 3 of the most common corneal refractive procedures; PRK, LASIK, and SMILE assessing ΔK/ΔSEQ ratio and its correlation with preoperative demographics including age, keratometry, pachymetry, cylinder value, and attempted myopic correction. The goal was to analyze the relative strength of each preoperative parameter in accounting for changes in ∆K/∆SEQ.

Patients and Methods

A total of 370 eyes from 102 male and 97 female patients (173 eyes PRK, 153 LASIK, and 44 SMILE) with ages ranging from 20 to 51 underwent refractive surgery for myopia between -0.25 and -7.71 D manifest refraction spherical equivalent (MRSE). All surgeries were performed at a single surgery center in Draper, Utah. The Pentacam was used for all optical measurements and data were gathered pre-operatively and then again 1-year post-operatively. Only patients who achieved emmetropia at a visual acuity of 20/25 or better were included.

Results

The mean ΔK/ΔSEQ ratio for LASIK (0.839 ± 0.020) was significantly greater than that of PRK (0.775 ± 0.022) and SMILE (0.709 ± 0.046). Age was found to negatively correlate with ΔK/ΔSEQ for both LASIK (r = -0.177) and SMILE (r = -0.451) procedures. Pre-op keratometry was found to negatively correlate with ΔK/ΔSEQ for LASIK (r = -0.202) but not for PRK or SMILE. Pre-op pachymetry was not correlated with ΔK/ΔSEQ for any of the procedures. Attempted myopic spherical equivalent (SEQ) correction was positively correlated with ΔK/ΔSEQ for LASIK (r = 0.236), PRK (r = 0.459), and SMILE (r = 0.304). Lastly, pre-op cylinder value was found to be correlated to ΔK/ΔSEQ in SMILE (r = -0.367), but not in LASIK or PRK.

Conclusion

The ΔK/ΔSEQ ratio not only differs depending on the procedure being done but also by pre-operative factors such as age, keratometry, attempted correction, and cylinder value. Multiple linear regression analysis revealed that the attempted correction had the greatest effect on ∆K/∆SEQ out of all parameters in LASIK and PRK. For SMILE, age had the greatest predictive value of the change in ∆K/∆SEQ. While the exact effect of these parameters will vary by surgeon, all of these should be factored into a refractive surgeon's nomograms in order to achieve optimal visual outcomes for their patients.

Prediction of Posterior-to-Anterior Corneal Curvature Radii Ratio in Myopic Patients after LASIK, SMILE, and PRK Using Multivariate Regression Analysis

The ratio of posterior-to-anterior curvature radii of the cornea (P/A ratio) is an important element in determining corneal refractive power. P/A ratio has been well studied in patients prior to undergoing refractive surgery, but its postoperative value remains less so. We aimed to examine the value of preoperative characteristics of refractive surgery patients in predicting the 1-year postoperative P/A ratio in LASIK, PRK, and SMILE using both linear and multivariate regression analyses. This was a retrospective study that included patients with manifest refraction spherical equivalents (MRSE) from -7.71D to -0.25D. In total, 164 eyes underwent LASIK, 183 underwent PRK, and 46 underwent SMILE. All patients had preoperative and 1-year postoperative front sagittal and back sagittal keratometry measurements at 4, 5, and 6 mm around the corneal vertex. Postoperative P/A after LASIK, PRK, and SMILE was found to be significantly correlated with MRSE and preoperative P/A. Stepwise variable selection in multivariate regression revealed that spherical equivalent was the most significant predictor of postoperative P/A. When coupled with other preoperative characteristics, including P/A, age, asphericity, and keratometry, the multivariate regressions were able to produce models with high predictive value in LASIK (adjusted R²: 0.957), PRK (adjusted R²: 0.934), and SMILE (adjusted R²: 0.894).

Comparison of Corneal Power Difference Maps with Achieved Myopic Correction Using Scheimpflug Tomography After LASIK, PRK, and SMILE

Purpose

To compare corneal power difference maps (∆maps) obtained from the Pentacam in patients with 1 year follow-up after LASIK, PRK, and SMILE with further stratification to low, moderate, and high myopia.

Patients and methods

This retrospective study was comprised of patients who had preoperative and 1-year postoperative power maps that were obtained-front sagittal (SagF), refractive power (RP), true net power (TNP), and total corneal refractive power (TCRP)-for evaluation. Measurements were recorded and compared at the 4mm, 5mm and 6mm pupil and apex zones. Comparisons were made between each specific power ∆map and the surgically induced refractive change (SIRC). Further analysis of the ∆maps was performed based on degree of myopia (high, moderate, and low). Correlation and agreement were also assessed with regression and limits of agreement (LoA).

Results

There were 172 eyes in the LASIK group, 187 eyes in the PRK group, and 46 eyes in the SMILE group. In the LASIK group, TNP ∆map at 5mm pupil zone had the least absolute mean difference with SIRC (0.007 ± 0.42D). In the PRK group, TNP ∆map at 5mm apex zone was most accurate compared to SIRC (0.066 ± 0.45D). In the SMILE group, TCRP ∆map at 4mm apex zone had the closest absolute value when compared to SIRC (0.011 ± 0.50D). There was good correlation and agreement for all three surgery groups, LASIK: r = 0.975, LoA -0.83D to +0.83D, PRK: r = 0.96, LoA -0.83D and +0.95D, and SMILE: r = 0.922, LoA -0.97 D to +0.99D.

Conclusion

TNP ∆maps most accurately measured corneal power in the LASIK and PRK groups while TCRP ∆maps were most accurate in the SMILE group. The degree of myopia may change which ∆map is most accurate.

Efficacy and safety of loteprednol etabonate versus fluorometholone in the treatment of patients after corneal refractive surgery: a meta-analysis

PURPOSE

To perform a systematic evaluation of the efficacy and safety of loteprednol etabonate (LE) 0.5% versus fluorometholone (FML) 0.1% for treating patients after corneal refractive surgery with the aim of providing an evidence-based rationale for clinical drug selection.

METHODS

Electronic databases (PubMed, EMBASE, Cochrane Library, Web of Science, WanFang, and CNKI) were searched (from inception to December 2021) for comparative clinical studies that evaluated LE versus FML treatment for post-corneal refractive surgery patients. Meta-analysis was performed using the RevMan 5.3 software. The pooled risk ratio (RR) and weighted mean difference (WMD) with corresponding 95% confidence interval (CI) were calculated.

RESULTS

Nine studies with a total sample size of 2677 eyes were included in this analysis. FML 0.1% and LE 0.5% produced a similar incidence of corneal haze within 6 months after surgery (P = 0.13 at 1 month, P = 0.66 at 3 months, and P = 0.12 at 6 months). There was no statistically significant difference between the two groups in terms of the mean logMAR postoperative uncorrected distance visual acuity (WMD: - 0.00; 95% CI: - 0.01 to 0.00; P = 0.29) and spherical equivalent (WMD: 0.01; 95% CI: - 0.01 to 0.03; P = 0.35). LE 0.5% appears to have a higher tendency to reduce the incidence of ocular hypertension compared FML 0.1%, but there was no statistical significance (RR: 0.63; 95% CI: 0.27 to 1.50; P = 0.30).

CONCLUSION

This meta-analysis demonstrated that LE 0.5% and FML 0.1% had comparable efficacy in preventing corneal haze and corticosteroid-induced ocular hypertension, with no difference in visual acuity in patients after corneal refractive surgery.

Local versus Systemic Therapy for Noninfectious Uveitis (NIU)

The mainstay of treatment for noninfectious uveitis (NIU) is immunosuppressant therapy. This may come in a localized form that is administered specifically to the eye or a systemic form that penetrates ocular tissues. Over the last twenty years, both local and systemic treatments have undergone advancements in pharmaceutical development. In this review, we will discuss new therapies and analyze the risks and benefits for all existing NIU therapies. Some of these therapies include topical, intravitreal, periocular, and systemic steroids, as well as systemic antimetabolites, tumor necrosis factor-α inhibitors, T-cell inhibitors, anti-CD 20 agents, interleukin-6 inhibitors, alkylating agents, and intravenous immunoglobulin.

Dose Uniformity of Loteprednol Etabonate (Submicron) Ophthalmic Gel 0.38% Compared with Prednisolone Acetate Ophthalmic Suspension 1

INTRODUCTION

Loteprednol etabonate (submicron) ophthalmic gel 0.38% (LE SM gel 0.38%) is a corticosteroid formulation designed to retain the nonsettling characteristics of loteprednol etabonate ophthalmic gel 0.5%, but with reduced drug particle size to improve ocular penetration, allowing for reduced dosing frequency. This study compared the dose uniformity of LE SM gel 0.38% with branded and generic prednisolone acetate (PA) 1% suspensions under simulated in-use dosing conditions.

METHODS

Drug concentrations in drops of LE SM gel 0.38% and PA 1% suspensions, expressed from bottles that were shaken or not shaken, were determined during 2 weeks of simulated on-label dosing (LE SM gel 0.38%: three times daily; PA suspensions: four times daily). Sedimentation of drug particles was assessed for each product using dispersion analysis.

RESULTS

The mean (SD) percent declared drug concentration of LE SM gel 0.38% over 2 weeks was 103.2% (1.3%) when the drug was dispensed from shaken bottles and 103.3% (1.5%) when dispensed from unshaken bottles. However, for branded and generic PA suspensions, mean (SD) percent declared concentrations were 102.2% (1.4%) and 98.3% (2.9%), respectively, when dispensed from shaken bottles; and 89.2% (18.6%) and 78.3% (13.5%), respectively, when dispensed from unshaken bottles. Dispersion analysis showed that drug particles in LE SM gel 0.38% remained fully suspended under accelerated sedimentation conditions, whereas both branded and generic PA suspension drug particles settled out of suspension.

CONCLUSIONS

LE SM gel 0.38% delivered the drug consistently at the declared concentration over the entire 2 weeks of simulated in-use dosing conditions, regardless of whether the drug was dispensed from shaken or unshaken bottles. However, both branded and generic PA suspensions required the bottle to be shaken to provide a consistent drug concentration.

The effect of loteprednol suspension eye drops after corneal transplantation

BACKGROUND

To compare the effect of loteprednol suspension eye drops after corneal transplantation with the effect of prednisolone acetate eye drops.

METHODS

A total of 234 patients (234 eyes) who underwent penetrating keratoplasty (PKP) and lamellar keratoplasty (LKP) were retrospectively included. Patients who received 1 % prednisolone acetate eye drops were defined as 1 % prednisolone acetate eye drop group (n = 96), and patients who received 0.5 % loteprednol suspension eye drops were defined as 0.5 % loteprednol suspension eye drop group (n = 138).

RESULTS

35 cases in 1 % prednisolone acetate eye drops group and 27 cases in 0.5 % loteprednol suspension eye drops group developed corticosteroid-induced ocular hypertension, and were defined as prednisolone acetate group and loteprednol group. No significant differences were observed in the average intraocular pressure (IOP) at 1 week, 1 month, 3 months or 12 months postoperatively. There were significant differences in the average IOP between the two groups at 6 months postoperatively (P = 0.001). There were no significant differences in the average best corrected visual acuity (BCVA) at 1, 3 and 12 months postoperatively between two groups. The average 6-month postoperative BCVA was significantly higher in the prednisolone acetate group than the loteprednol group (P < 0.05). There were no significant differences in the postoperative graft rejection rates between the two groups (P > 0.05).

CONCLUSIONS

0.5 % loteprednol suspension eye drops may be considered for long-term use after corneal transplantation.

Loteprednol etabonate gel 0.5% vs prednisolone acetate suspension 1% for the treatment of inflammation after cataract surgery in children

PURPOSE

To compare loteprednol etabonate (LE) gel 0.5% with prednisolone acetate suspension (PA) 1% for the treatment of inflammation after cataract surgery in children.

SETTING

Eleven sites in the United States.

DESIGN

Randomized, double-masked, parallel-group, noninferiority study.

METHODS

Eligible patients were aged 11 years or younger and candidates for routine, uncomplicated cataract surgery. Patients were randomized to a 4-week postsurgical regimen with LE gel 0.5% or PA 1%, twice on the day of surgery, 4 times daily for 2 weeks, twice daily for 1 week, and once daily for 1 week. Assessments included anterior chamber (AC) cells/flare, anterior chamber inflammation (ACI), synechiae, precipitates on the intraocular lens/cornea, visual acuity, and intraocular pressure.

RESULTS

The intent-to-treat population comprised 105 patients (LE gel, n = 53; PA 1%, n = 52) including 52 patients aged 3 years or younger. Patients achieved a similar mean ACI grade on postoperative day 14 (primary efficacy endpoint) whether treated with LE gel 0.5% or PA 1% (difference = 0.006, 2-sided 95% CI, -0.281 to 0.292). Similar ACI outcomes additionally were observed in patients aged 3 years or younger. LE gel 0.5% and PA 1% also appeared equally effective in resolving inflammation at all visits (days 7, 14, and 28 postsurgery), based on categorical distributions of ACI, AC cells, and AC flare scores/grades (P ≥ .06). Synechiae and corneal/IOL precipitates occurred infrequently with no significant differences between groups. No safety or tolerability concerns were identified, including no treatment-related IOP increases.

CONCLUSIONS

LE gel 0.5% was safe and effective in treating pediatric postcataract surgical inflammation, with similar outcomes as PA 1%.

Systematic Review on Therapeutic Strategies to Minimize Corneal Stromal Scarring After Injury

OBJECTIVES

To evaluate recent studies on available and experimental therapies in preventing or minimizing corneal stromal scarring after injury.

METHODS

We performed an Entrez PubMed literature search using keywords "cornea," "scarring," "haze," "opacity," "ulcer," "treatments," "therapies," "treatment complications," and "pathophysiology" resulting in 390 articles of which 12 were analyzed after filtering, based on English language and publication within 8 years, and curation for relevance by the authors.

RESULTS

The 12 articles selected included four randomized control trials (RCTs) (two were double-blinded placebo-controlled RCTs, one was a prospective partially masked RCT, and one was an open-label RCT), two retrospective observational studies, and six laboratory-based studies including two studies having in vivo and in vitro experiments, one was in vivo study, one was ex vivo study, and the last two were in vitro studies. The current mainstay for preventing or minimizing corneal scarring involves the use of topical corticosteroids and local application of mitomycin C. However, supportive evidence for their use in clinical practice from well-designed RCTs is lacking. Laboratory studies on topical rosiglitazone therapy, vitamin C prophylaxis, gene therapy, and stem cell therapy have shown promising results but have yet to be translated to clinical research.

CONCLUSION

There is a need for more robust randomized controlled trials to support treatments using topical corticosteroids and mitomycin C. Furthermore, their clinical efficacy and safety profile should be compared with new treatments that have shown promising results in the laboratory setting. Ultimately, the goal should be to personalize cornea scarring treatment according to the most effective treatment for the specific underlying pathology.

Risk of intraocular pressure elevation after topical steroids in children and adults: A systematic review

Topical steroids may induce a rise in intraocular pressure. The risk may increase with prolonged use, high frequency of administration, young age, higher ocular penetrance and higher anti-inflammatory potency. We aimed to study this relationship by comparing published rates of intraocular pressure elevation following administration of topical steroids and compared the risk of higher versus lower dosage regimes, high- versus low-potency/penetration steroids and adults versus children. Data sources used were Ovid Embase, Ovid Medline, the Cochrane Central Register of Controlled Trials, Web of Science, Scopus, CINHAL Plus and LILACS. Eligible studies were randomised controlled trials of topical steroids versus any other topical steroid, nonsteroidal anti-inflammatory drugs, placebo or vehicle, or a different mode of administration administered for 7 days or longer that reported intraocular pressure elevation from baseline as >10, 6-15 or >15 mm Hg in adults or children. Risks of bias were reviewed using the GRADE quality approach. Data were extracted into the software package, RevMan, Version 5 (Cochrane Collaboration). In total, 43 studies were included. Meta-analysis was not possible. Topical steroids of lower anti-inflammatory potency, and with reduced intraocular penetration, are associated with reduced incidence of intraocular pressure elevation. A comparison of data in children and adults is limited by the use of different reporting systems. The principal obstacle to meta-analysis is the different reporting systems used to categorise intraocular pressure elevation. We recommend future studies should report intraocular pressure elevation >10 mm Hg from baseline to allow meta-analysis of data.

Real world use of loteprednol etabonate ophthalmic gel 0.5% in cases representative of comorbid pathologies responding to minimally invasive glaucoma surgery

Purpose

With the increasing use of minimally invasive surgical techniques for intraocular pressure (IOP) lowering in glaucoma patients, there is a need to examine best practices regarding the postoperative management of these patients. Corticosteroids, though effective in controlling postoperative ocular pain and inflammation, present distinct challenges in glaucoma surgery patients, as their use can be associated with IOP elevation. Loteprednol etabonate (LE) is an ocular corticosteroid designed to have an improved safety profile relative to other corticosteroids.

Methods

We report here a representative selection of cases in which patients were successfully treated with LE ophthalmic gel 0.5% (LE gel) following a variety of minimally invasive glaucoma surgery (MIGS) procedures. Cases included patients undergoing various procedures including a Trabectome combined with cataract surgery; micro-stent surgery (iStent) combined with cataract surgery; supraciliary CyPass Micro-Stent placement combined with cataract surgery; Kahook Dual Blade goniotomy; and ab interno canaloplasty using the iTrack catheter.

Observations

In all cases, use of LE gel during the postoperative period appeared effective and safe in reducing inflammation and controlling pain. No adverse events or IOP elevations were noted, even in those patients continuing use of LE gel past the postoperative period for longer than six months with documented follow-up. In two cases, patients with elevated IOP using either prednisolone or difluprednate postoperatively were switched to LE gel, with a subsequent reduction in IOP.

Conclusions

This selection of cases involving patients undergoing MIGS suggests that LE gel may be an effective and safe option for treating postoperative inflammation and pain following such procedures with minimal to no effect on IOP or other negative sequalae.

Rheological Properties, Dissolution Kinetics, and Ocular Pharmacokinetics of Loteprednol Etabonate (Submicron) Ophthalmic Gel 0.38

Purpose: To evaluate rheological properties, in vitro dissolution, and in vivo ocular pharmacokinetics of loteprednol etabonate (LE) (submicron) ophthalmic gel 0.38%.

Methods: The viscosity of the LE gel 0.38% formulation was measured with a controlled stress rheometer. Dissolution kinetics were evaluated in a fixed-volume and flow-through assay. Rabbits received a single instillation of LE (submicron) gel 0.38% (both eyes), and concentrations of LE in ocular tissues were determined through 24 h by liquid chromatography with tandem mass spectrometry. Where indicated, comparators included micronized LE gel 0.38%, 0.5% (Lotemax^® gel), and 0.75%.

Results: LE (submicron) gel 0.38% exhibited shear-thinning characteristics similar to LE gel 0.5% with nearly identical yield stress. LE (submicron) gel 0.38% released 2.6-fold more LE into the dissolution medium than micronized LE gel 0.5% over 30 s in the fixed-volume dissolution assay, and submicron LE attained higher concentrations of dissolved LE than micronized LE gel 0.38% in the flow-through dissolution assay. In rabbits, the maximal concentration and area-under-the-curve over 24 h for LE in aqueous humor were 2.5- and 1.8-fold higher, respectively, for LE (submicron) gel 0.38% versus micronized LE gel 0.5% (both P < 0.001). Pharmacokinetic parameters were similar for most other tissues.

Conclusions: LE (submicron) gel 0.38% demonstrated similar rheological properties to micronized LE gel 0.5% but faster dissolution, thus providing similar or higher LE concentrations in the aqueous humor, cornea, and iris-ciliary body after ocular dosing in rabbits despite a lowered concentration of drug in the formulation.

Loteprednol etabonate for inflammatory conditions of the anterior segment of the eye: twenty years of clinical experience with a retrometabolically designed corticosteroid

INTRODUCTION

Topical corticosteroids are an important pharmacotherapy for the management of various inflammatory conditions affecting the anterior segment of the eye. However, medications in this class are associated with well-known risks including increased intraocular pressure (IOP) and development of cataracts. The topical corticosteroid loteprednol etabonate (LE) was developed with the specific intention of minimizing these side effects.

AREAS COVERED

The focus of this review is to examine published efficacy and safety data for LE, a drug engineered to undergo rapid metabolism to inactive metabolites with the goal of improved safety. Two decades of clinical research focused on LE formulations are reviewed, including the use of LE in combination with tobramycin. The cumulative body of experience affirms the concept that the molecular design of LE confers certain safety benefits without compromising the desired anti-inflammatory efficacy of a topical corticosteroid.

EXPERT OPINION

Loteprednol etabonate is a mainstay for topical therapy of a wide variety of commonplace and niche conditions of the ocular surface and the anterior segment, including in the healing post-operative patient. Its versatility and safety allow eye care providers to recommend both acute induction as well as chronic maintenance therapy with appropriate follow-up.