Topical Ocular TRPV1 Antagonist SAF312 (Libvatrep) for Postoperative Pain After Photorefractive Keratectomy

Purpose

Evaluation of safety and efficacy of topical ocular SAF312 (Libvatrep) in post-photorefractive keratectomy (PRK) pain.

Methods

In this placebo (vehicle)-controlled, participant- and investigator-masked study, 40 participants were randomized (1:1) to two treatment sequences in a bilateral PRK crossover design (SAF312 2.5% followed by vehicle [or vice versa], one eye drop, four times daily for 72 hours after PRK). Primary endpoints were visual analog scale (VAS) pain scores at 6 hours after first drop of study drug and average VAS scores over 0 to 12 hours postoperatively. Secondary endpoints included postoperative oral rescue medication (ORM) use and adverse events (AEs).

Results

All 40 participants completed the study. Both primary endpoints were met; mean difference in VAS pain scores between SAF312- and vehicle-treated eyes was -11.13 (P = 0.005, -25%) at 6 hours postoperatively and -8.56 (P = 0.017, -22%) over 0 to 12 hours. Mean VAS pain scores with SAF312 were consistently lower than with vehicle from 1 hour postoperatively up to 30 hours (P ≤ 0.10 observed in 8/11 time points). Less ORM was taken with SAF312 up to 0 to 72 hours postoperatively, with a trend of fewer participants taking ORM at 0 to 24 hours postoperatively with SAF312 versus vehicle. No serious AEs were reported. All ocular AEs were mild and transient, and none were drug related. SAF312-treated eyes showed no delay in wound healing and had a lower grade 4 conjunctival hyperemia 24 hours postoperatively versus vehicle-treated eyes.

Conclusions

SAF312 was well tolerated and effective in reducing ocular pain post-PRK.

Translational Relevance

Topical SAF312 presents a new therapeutic option for patients undergoing PRK.

Bandage contact lens soaked in 0.1% diclofenac to relieve early postoperative pain and foreign body sensation after transepithelial photorefractive keratectomy

PURPOSE

To study the effects of a bandage contact lens immersed in 0.1% diclofenac on pain management for patients undergoing transepithelial photorefractive keratectomy (TPRK).

METHODS

In a prospective, comparative, contralateral, randomized, double-masked study, we assessed a total of 51 patients. The eyes of each patient were randomly divided into two groups. After TPRK, a normal soft bandage contact lens was placed on one eye as the control group, and a bandage contact lens soaked in diclofenac was placed on the other eye as the experimental group. When the bandage contact lens was not removed, postoperative pain and other ocular discomforts were compared at 2, 18, and 24 h and 2, 3, 4, and 5 postoperative days. Patients were then examined after 1 month. Visual acuity and subepithelial haze were also evaluated.

RESULTS

The mean pain score was 2.69 ± 1.96 in the control group, which was significantly higher than that in the experimental group, which received the diclofenac-soaked bandage contact lens at 2 postoperative hours. The statistical difference between the two groups' mean foreign body sensation at 2 postoperative hours was detected (p = 0.035). No differences were detected between the two groups' subepithelial haze scores or visual acuity.

CONCLUSION

A bandage contact lens soaked in 0.1% diclofenac solution can be used as a potential drug-delivery system to relieve early postoperative pain and foreign body sensation after TPRK.

Intra-Operative Discomfort in Photorefractive Keratectomy

Purpose

Photorefractive keratectomy (PRK) remains a viable, safe, and efficacious option for patients wishing to correct refractive errors. One of its most significant drawbacks is pain. While post-operative pain has been well studied with different management options, intra-operative pain has been less well defined. The purpose of this study was to characterize intra-operative pain during PRK in regard to eye operated on, gender, excimer platform used, surgeon, and age.

Patients and Methods

A total of 134 patients (264 eyes) were prospectively randomized to undergo bilateral PRK of either the right eye first or the left eye first followed immediately by the fellow eye. In the immediate post-operative period they were surveyed using an 11-point Numeric Rating Scale regarding intra-operative pain or discomfort experienced in each eye. Resultant pain scores were then analyzed via two sample z-test and analysis of variance (ANOVA) to characterize pain overall as well as comparing first versus second eye operated on, right versus left eye, male versus female, excimer platform used, inter-surgeon variability, and age.

Results

Of 264 eyes surveyed the mean pain experienced on a 0–10 pain scale was 1.13 (minimal discomfort). There was no statistically significant difference in pain or discomfort when comparing first versus second eye operated on, right versus left eye, male versus female, excimer platform used, operating surgeon, or age.

Conclusion

Intra-operative pain or discomfort experienced by patients is minimal. The absence of statistically significant differences in pain scores studied implies that standard of care procedures achieve adequate analgesia in PRK.

Nepafenac-Loaded Cyclodextrin/Polymer Nanoaggregates: A New Approach to Eye Drop Formulation

The topical administration route is commonly used for targeting therapeutics to the eye; however, improving the bioavailability of drugs applied directly to the eye remains a challenge. Different strategies have been studied to address this challenge. One of them is the use of aggregates that are formed easily by self-assembly of cyclodextrin (CD)/drug complexes in aqueous solution. The aim of this study was to design a new eye drop formulation based on aggregates formed between CD/drug complexes. For this purpose, the physicochemical properties of the aggregates associated with six CDs and selected water-soluble polymers were analysed. Complex formation was studied using differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR) and ¹H nuclear magnetic resonance spectroscopy (¹H-NMR). Results showed that HPβCD performed best in terms of solubilization, while γCD performed best in terms of enhancing nanoaggregate formation. Formation of inclusion complexes was confirmed by DSC, FT-IR and ¹H-NMR studies. A mixture of 15% (w/v) γCD and 8% (w/v) HPβCD was selected for formulation studies. It was concluded that formulations with aggregate sizes less than 1 µm and viscosity around 10–19 centipoises can be easily prepared using a mixture of CDs. Formulations containing polymeric drug/CD nanoaggregates represent an interesting strategy for enhanced topical delivery of nepafenac.

Efficacy and safety of transepithelial photorefractive keratectomy

Transepithelial photorefractive keratectomy (PRK) was introduced to prevent complications from conventional PRK and femtosecond laser-assisted laser in situ keratomileusis (LASIK). In the 2-step platform, phototherapeutic keratectomy is followed by PRK. It did not show notable safety or efficacy superiorities over conventional PRK. In the conventional single-step transepithelial PRK, ablation of epithelium and stroma occurs in a single continuous session by an Amaris laser. It showed better comparative safety results. Reverse single-step transepithelial PRK and the platform using smart-pulse technology were recent improvements in the single-step Amaris laser. They provide a smoother postablative stromal bed counter. In the refined single-step platform, a modified nomogram is used for determination of ablation parameters, along with modifications in postablative measures. It yielded better comparative results in hyperopia. Controlled trials comparing reverse, smart-pulse technology-equipped, or refined platforms of single-step transepithelial PRK with other modern laser-assisted methods could provide more robust evidence on the topic. Some key elements with significant roles in post-transepithelial PRK outcomes are discussed.

Application of autologous serum eye drops after pterygium surgery: a prospective study

PURPOSE

The study aims to determine the effect of 50% autologous serum drops (ASD) on corneal healing and patient comfort following pterygium surgery.

METHODS

Fifty eyes of 50 patients who underwent pterygium excision combined with autologous conjunctival graft were included in this prospective randomized study: in 25 eyes, 50% ASD. In the remaining 25 eyes, conventional artificial tears (CAT) were applied postoperatively until corneal epithelium had completely epithelialized. Corneal epithelium healing speed, visual analog scale (VAS) for postoperative pain assessment, conjunctival inflammation, and recurrences were evaluated. Patients were followed up for 6 months.

RESULTS

Mean corneal epithelium closure time was 3.16 ± 0.37 days (range 3 and 4 days) in ASD group and 4.96 ± 0.84 days in CAT group (range 4 and 6 days), and the difference was statistically significant (p < 0.001). VAS scores were significantly lower in ASD group than CAT group in the first 5 days after surgery. In 9 of 50 eyes, moderate conjunctival inflammation continued 1 month: 4 (16%) in ASD group and 5 (20%) in CAT group (p = 0.713). In total, pterygium recurrence was seen in 5 (10%) eyes: 2 eyes (8%) in ASD group and 3 eyes (12%) in CAT group (p = 0.637).

CONCLUSION

ASD accelerated corneal epithelial healing following pterygium surgery. ASD group had lesser pain that was seem to be related with accelerated corneal epithelial healing.

Nepafenac Ophthalmic Suspension 0.3% for the Management of Ocular Pain After Photorefractive Keratectomy

PURPOSE

To investigate the effect of nepafenac 0.3% in a once daily dosage regarding pain and healing after photorefractive keratectomy (PRK).

METHODS

This was a prospective, comparative, contralateral randomized study of 35 patients undergoing PRK for the correction of low to moderate myopia and myopic astigmatism. After randomization, patients received nepafenac 0.3% ophthalmic suspension once daily in one eye (nepafenac 0.3% group) and nepafenac 0.1% ophthalmic suspension three times a day in the other eye (nepafenac 0.1% group) until the second postoperative day. Pain was evaluated every 2 hours on the day of the operation and then once daily using a scale ranging from 0 to 4. Patients were then examined at 2 weeks and 1, 3, 6, and 12 postoperative months. Visual acuity and subepithelial haze were also assessed.

RESULTS

No differences were detected between groups in pain scores, subepithelial haze scores, or visual acuity. Refractive predictability was also similar.

CONCLUSIONS

Nepafenac 0.3% ophthalmic suspension in a daily regimen after PRK seems to be an effective treatment for pain and ocular discomfort with effects similar to the 0.1% suspension. [J Refract Surg. 2018;34(3):171-176.].

Ophthalmic nepafenac use in the Netherlands and Denmark

Purpose

To describe nepafenac use in the Netherlands and Denmark with reference to its approved indications. For context, we also describe the use of ketorolac and diclofenac.

Methods

We identified users in the PHARMO Database Network (the Netherlands, 2008–2013) and the Danish national health registers (Denmark, 1994–2014). We described prevalence of cataract surgery and duration of use in patients with cataract surgery with and without diabetes.

Results

In the Netherlands, 9530 nepafenac users (mean age, 71 years; 60% women) contributed 12 691 therapy episodes, of which 21% had a recently recorded cataract surgery. Of 2266 episodes in adult non‐diabetic patients with cataract surgery, 60% had one bottle dispensed (treatment duration ≤21 days). Of 441 episodes in adult diabetic patients with cataract surgery, 90% had up to two bottles dispensed (≤60 days).

Denmark had 60 403 nepafenac users (mean age, 72 years; 58% women) and 73 648 episodes (41% had recorded cataract surgery). Of 26 649 nepafenac episodes in adult non‐diabetic patients with cataract surgery, 92% had one bottle dispensed. Of 3801 episodes in adult diabetic patients with cataract surgery, 99.8% had up to two bottles dispensed.

Use patterns of nepafenac, ketorolac and diclofenac were roughly similar in the Netherlands, but not in Denmark.

Conclusion

Less than half of therapy episodes were related to cataract surgery; around 90% of episodes with surgery were within the approved duration. Underrecording of ophthalmic conditions and procedures was a challenge in this study.

Pain perception description after advanced surface ablation

Purpose

The objective of this study was to characterize the evolution of ocular pain after advanced surface ablation (ASA) to improve strategies in postoperative pain management.

Methods

This was a multicenter, prospective, descriptive, cohort study. The inclusion criteria were healthy individuals ≥18 years old receiving bilateral alcohol-assisted surface ablation with epithelial removal. Pain intensity was evaluated with the visual analog scale (VAS) and the numeric pain rating scale before and after surgery. Comorbidities (photophobia, burning, tearing, and foreign body sensation) and Hospital Anxiety and Depression (HAD) questionnaire were evaluated before and at 6 hours after surgery. Postoperative treatments included cold patch, topical cold antibiotics, topical steroids, and benzodiazepines.

Results

Thirty-two consecutive patients having similar profiles of postoperative pain evolution were included. At 0.5 hour after ASA, the pain score by VAS was 37±20 mm, and the maximum pain, 61±31 mm, occurred at 24 hours. Afterward, it decreased progressively until 72 hours after surgery (19±20 mm). Most patients (81%) scored >60 mm, and 44% required rescue medication. Among the comorbidities, all patients had photophobia and 84% had burning sensation. At 6 hours, the HAD score was 5.4±3.9, within the range of values considered as normal.

Conclusion

Postoperative acute ocular pain after ASA showed a characteristic evolution over time. Recognition of the pattern could be important for improving the acceptance of ASA and for improving strategies in pain management in the postoperative period.

Efficacy of systemic diclofenac sodium on intravitreal concentration

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs), as an alternative, are replacing corticosteroids in ocular inflammatory diseases. Diclofenac has been used mainly topically, and recent focus has been on intravitreal delivery. Both of these methods have been shown to have complications in long-term application.

PURPOSE

To assess the efficacy of slow release oral diclofenac sodium on intravitreal concentration in experimental model of chemically injured eyes.

METHODS

In an experimental double-masked clinical trial, right eyes of 24 albino rabbits were chemically injured by 1 N NaOH. One hour after chemical injury, 10 cc suspension gavage containing 100 mg slow release diclofenac sodium was administered in all cases. 2, 4, 6, 12, 24, 48 h after gavage, vitreous samples were obtained in all cases. Intravitreal concentration of diclofenac sodium was evaluated in all samples using high-performance liquid chromatography (HPLC) method.

RESULTS

Intravitreal diclofenac levels by oral intake were enhanced by the inflammation in all the measurements. In inflamed eyes, diclofenac concentration was ten times more than control eye (2.658 ± 0.344 vs. 0.242 ± 0.0279 and 1.617 ± 0.527 vs. 0.148 ± 0.095; in 2 and 4 h, respectively). After 6 h, diclofenac concentration was statistically different, although it reduced below 1 μg/ml.

CONCLUSION

Diclofenac is delivered to the inflamed eye more than healthy eye. It seems that by oral diclofenac consumption, it is possible to make a significant intravitreal concentration.

Ocular pain and discomfort after advanced surface ablation: an ignored complaint

Purpose

Laser vision correction is one of the most commonly performed elective surgical procedures in ophthalmology. Generally, discomfort besides pain (photophobia, burning sensation, tearing, and foreign body sensation) after these procedures is not taken into consideration in the clinical practice. The objective is to provide data on these symptoms and their relevance after advanced surface ablation (ASA).

Methods

Single-center survey study based on a structured questionnaire relative to the patients’ perceived symptoms after ASA. Inclusion criteria were: ≥18 years old, no ocular disease, with myopia (0.75 to 9 D) or hyperopia (0.25 to 5 D) with or without astigmatism, receiving ASA on at least one eye. All procedures were performed by the same surgeon. A descriptive analysis was performed.

Results

Seventy-three consecutive patients (34 men and 39 women) were included in the study. The median (range) of age was 33 (19–64) years. Sixty-nine patients had surgery done on both eyes. Postoperative pain was the most frequent comorbidity (97% [95% confidence interval {CI}: 90–100]) with a median (range) of intensity (verbal numerical rating scale) score of 7 (2–10). Photophobia: 85% (95% CI: 75–92); burning sensation: 62% (95% CI: 50–73); tearing: 59% (95% CI: 47–70); and foreign body sensation: 48% (95% CI: 36–60) were also prevalent postoperative symptoms. Pain during ASA was reported for 44% (95% CI: 32–56) of patients.

Conclusion

Comorbidities such as pain, photophobia, burning sensation, tearing, and foreign body sensation are prevalent after ASA procedure. Postoperative pain should be taken into consideration due to its prevalence and intensity. A new and more efficient postoperative analgesic protocol should be established.

Corneal Regeneration After Photorefractive Keratectomy: A Review

Photorefractive keratectomy (PRK) remodels corneal stroma to compensate refractive errors. The removal of epithelium and the ablation of stroma provoke the disruption of corneal nerves and a release of several peptides from tears, epithelium, stroma and nerves. A myriad of cytokines, growth factors, and matrix metalloproteases participate in the process of corneal wound healing. Their balance will determine if reepithelization and stromal remodeling are appropriate. The final aim is to achieve corneal transparency for restoring corneal function, and a proper visual quality. Therefore, wound-healing response is critical for a successful refractive surgery. Our goal is to provide an overview into how corneal wounding develops following PRK. We will also review the influence of intraoperative application of mitomycin C, bandage contact lenses, anti-inflammatory and other drugs in preventing corneal haze and post-PRK pain.

Efficacy and safety of pain relief medications after photorefractive keratectomy: review of prospective randomized trials

The objective of this review was to provide a comprehensive overview and comparison of results from all prospective randomized trials published to date of medications used to treat pain after photorefrative keratectomy (PRK). A PubMed database search revealed 23 prospective and randomized studies. They included the following classes of medications: nonsteroidal antiimflammatory drugs (NSAIDs), anesthetics, opiates, acetaminophen, gabapentin, and pregabalin. The studies found that although the efficacy of drugs tended to be similar, tetracaine 1% and nepafenac 0.1% tended to have the most analgesic effect. Delayed corneal reepithelialization was a common side effect of both topical anesthetics and topical NSAIDs. Tetracaine 1% resulted in the most significant delay in reepithelialization when tested against placebo control compared with other topical medications tested against placebo. Concomitant use of topical NSAIDs and topical anesthetics, especially tetracaine, may have to be avoided to minimize the risk for delayed corneal healing.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Nepafenac 0.1% versus fluorometholone 0.1% for preventing cystoid macular edema after cataract surgery

PURPOSE

To compare a topical nonsteroidal antiinflammatory drug (nepafenac 0.1%) and a topical steroidal antiinflammatory drug (fluorometholone 0.1% ) in preventing cystoid macular edema (CME) and blood-aqueous barrier (BAB) disruption after small-incision cataract extraction with foldable intraocular lens (IOL) implantation.

SETTING

Shohzankai Medical Foundation, Miyake Eye Hospital, Nagoya, Japan.

DESIGN

Randomized double-masked single-center clinical trial.

METHODS

Patients were randomized to receive nepafenac 0.1% eyedrops or fluorometholone 0.1% eyedrops for 5 weeks after phacoemulsification with foldable IOL implantation. The incidence and severity of CME were evaluated by fluorescein angiography, retinal foveal thickness on optical coherence tomography, and BAB disruption on laser flare-cell photometry.

RESULTS

Thirty patients received nepafenac and 29 patients, fluorometholone. Five weeks postoperatively, the incidence of fluorescein angiographic CME was significantly lower in the nepafenac group (14.3%) than in the fluorometholone group (81.5%) (P<.0001). The fovea was thinner in the nepafenac group than in the fluorometholone group at 2 weeks (P=.0266) and 5 weeks (P=.0055). At 1, 2, and 5 weeks, anterior chamber flare was significantly less in the nepafenac group than in the fluorometholone group (P<.0001, P<.0001, and P=.0304, respectively). The visual acuity recovery from baseline was significantly greater in the nepafenac group (80.0%) than in the fluorometholone group (55.2%) (P=.0395). There were no serious side effects in either group.

CONCLUSION

Nepafenac was more effective than fluorometholone in preventing angiographic CME and BAB disruption, and results indicate nepafenac leads to more rapid visual recovery.

Topical ophthalmic NSAIDs: a discussion with focus on nepafenac ophthalmic suspension

The removal of diclofenac sodium ophthalmic solution as a viable pharmaceutical entity in September 1999 from the US market spurred considerable interest in the general safety and effectiveness of topical ophthalmic NSAIDs for treatment of anterior segment inflammation. In late 1999 the use of topical ocular NSAIDs declined in the US as a result of incidents involving corneal melts and toxicity surrounding use of generic diclofenac. However, since the removal of diclofenac sodium ophthalmic solution from the marketplace, ophthalmic NSAIDs have regained use as viable pharmacotherapeutic entities. Moreover, several new ophthalmic NSAID products have recently been introduced for commercial use in the US including the novel chemical entity nepafenac. The purpose of this report is to revisit the use of topical ophthalmic NSAIDs for the treatment of surgically induced anterior segment inflammation with a particular focus on nepafenac. Nepafenac is unique among ophthalmic NSAIDs in that it is a prodrug deaminated to amfenac, a highly effective non-selective cyclooxygenase inhibitor. In the case of topical ophthalmic NSAIDs, practitioners should carefully weigh the cost-benefit of implementing “highly potent” new drug products because perturbations in pharmacodynamic response due to the inherent novelty in terms of chemical designs may outweigh the demonstrated replicative pharmacologic action of all topical ophthalmic NSAIDs.

Effect of preemptive topical diclofenac on postoperative pain relief after photorefractive keratectomy

PURPOSE

To assess the prophylactic effect of preoperative application of topical diclofenac on postoperative pain control in patients having photorefractive keratectomy (PRK).

SETTING

Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.

DESIGN

Randomized masked clinical trial.

METHODS

In this paired-eye study, patients having bilateral PRK received 1 drop of diclofenac 0.1% in 1 eye and 1 drop of placebo in the fellow eye 2 hours before PRK. Postoperatively, both arms of the trial (both eyes of each patient) received topical diclofenac every 6 hours for 2 days. One day and 2 days postoperatively, patients were asked to rate the perceived pain in each eye using an 11-point verbal numerical rating scale. A trained examiner noted the eye-specific responses.

RESULTS

All 70 patients (140 eyes) completed the study and were included in the statistical analysis. Twenty-four hours after PRK, patients reported pain scores that were clinically and statistically significantly lower in the eyes pretreated with diclofenac than in the fellow eyes (0.97 versus 2.09) (P=.018). Pain scores at 2 days did not differ significantly (P=.877).

CONCLUSION

Administration of a single drop of topical diclofenac 0.1% 2 hours before PRK seemed to increase the efficacy of postoperative pain management in a clinically and statistically significant manner.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Nonsteroidal anti-inflammatory drugs in ophthalmology

Nonsteroidal anti-inflammatory drugs (NSAIDs) are increasingly employed in ophthalmology to reduce miosis and inflammation, manage scleritis, and prevent and treat cystoid macular edema associated with cataract surgery. In addition, they may decrease postoperative pain and photophobia associated with refractive surgery and may reduce the itching associated with allergic conjunctivitis. In recent years, the U.S. Food and Drug Administration has approved new topical NSAIDs, and previously approved NSAIDs have been reformulated. These additions and changes result in different pharmacokinetics and dosing intervals, which may offer therapeutic advantages. For example, therapeutic effects on diabetic retinopathy and age-related macular degeneration may now be achievable. We provide an updated review on NSAIDs and a summary of their current uses in ophthalmology with attention to potential future applications.

Effect of topical 0.5% morphine on postoperative pain after photorefractive keratectomy

PURPOSE

To investigate safety and efficacy of 0.5% morphine drops for pain control after photorefractive keratectomy (PRK).

METHODS

In a double-blind prospective study, 40 patients were randomized to either 0.5% morphine drops (n=20) or vehicle control (n=20). Treatment occurred every 2 hours following PRK on the day of the procedure, then four times daily on postoperative days 1 through 3. Patients completed pain assessment questionnaires (visual descriptor, numerical rating, visual analog scales, and oral analgesic consumption) every 2 hours while awake during the treatment period. Daily average and maximum scores were compared between the two groups. Patients were examined daily for 4 days after PRK, weekly for 4 weeks, then monthly for 3 months. Epithelial healing, corneal haze, and refractive outcomes were compared.

RESULTS

Both average and maximum pain scores were lower in the morphine group than in the vehicle control group on all scales and during all 4 days after PRK. Statistical significance (P<.05) was reached on numeric rating scale on procedure day and on postoperative day 1. The difference between the groups on the visual analog scale was statistically significant on procedure day, and on postoperative days 1 and 2. Oral analgesic consumption was higher in the vehicle control group on postoperative day 2. No difference between groups was noted in epithelial healing or refractive outcomes. Stromal haze scores were lower in the morphine group, but the difference was not statistically significant.

CONCLUSIONS

Topical 0.5% morphine may be an effective and safe method of pain control after PRK.