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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 33  |  Issue : 2  |  Page : 604-610

Evaluation of nepafenac eye drops in prevention of macular edema following cataract surgery


1 Department of Ophthalmology, Faculty of Medicine, College of Medicine, Menoufia University, Menoufia, Egypt
2 Department of Ophthalmology, College of Medicine, Menoufia University, Menoufia, Egypt

Date of Submission27-Oct-2019
Date of Decision23-Nov-2019
Date of Acceptance01-Dec-2019
Date of Web Publication27-Jun-2020

Correspondence Address:
Marwa A Al Said
Department of Ophthalmology, College of Medicine, Menoufia University, Menoufia
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/mmj.mmj_333_19

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  Abstract 


Objective
The aim was to evaluate the prophylactic use of topical NSAIDs instead of topical steroids preoperatively and postoperatively to reduce the incidence of macular edema.
Background
Macular thickening is a postoperative complication following cataract surgery, even with uncomplicated small-incision phacoemulsification surgery. Subclinical cystoid macular edema (CME) is diagnosed with fluorescein angiography as leakage from perifoveal dilated capillaries without visual acuity affection. After uncomplicated phacoemulsification in healthy individuals, the incidence of subclinical CME has been reported to be less than 20%.
Patients and methods
The study included 75 patients who visited the Outpatient Clinics, previously diagnosed as having cataract between January 2018 and December 2018. The eligible 75 patients were randomly allocated into three equal groups (25 patients each) by using a computer-generated list of random permutations according to the drugs that were used.
Results
There was no statistically significant difference between the study groups. The preoperative mean of Best-corrected visual acuity (BCVA) was 1.56, 1.39, and 1.48 in the control, nepafenac, and dexamethasone groups, and there was no significant difference among them (P = 0.433). Regarding central macular thickness, there was no statistically significant difference between the study groups (P = 0.126). Despite being not statistically different from each other in the preoperative period regarding central macular thickness, there was improvement in the nepafenac and dexamethasone groups when compared with the placebo group at 1-week, 1-month, and 3-month follow-up visits.
Conclusion
This study revealed the prophylactic effect of topical NSAIDs and steroids in reducing the frequency and severity of CME in patients undergoing cataract surgery.

Keywords: cataract surgery, dexamethasone, macular edema–nepafenac


How to cite this article:
Ellakwa AF, Badawy NM, Al Said MA. Evaluation of nepafenac eye drops in prevention of macular edema following cataract surgery. Menoufia Med J 2020;33:604-10

How to cite this URL:
Ellakwa AF, Badawy NM, Al Said MA. Evaluation of nepafenac eye drops in prevention of macular edema following cataract surgery. Menoufia Med J [serial online] 2020 [cited 2020 Oct 24];33:604-10. Available from: http://www.mmj.eg.net/text.asp?2020/33/2/604/287781




  Introduction Top


Macular thickening is a well-known postoperative complication after cataract surgery, even with uncomplicated small-incision phacoemulsification surgery[1].

Subclinical cystoid macular edema (CME) is diagnosed with fluorescein angiography as leakage from perifoveal dilated capillaries without visual acuity affection. After uncomplicated phacoemulsification in healthy individuals, the incidence of subclinical CME has been reported to be less than 20%[1].

Clinical CME can be identified on bio-microscopic examination and is associated with decreased visual acuity. After phacoemulsification surgery, clinical CME has been reported to be less than 3% in healthy patients[2].

The pathogenesis of CME is disruption of blood–retinal barrier by inflammatory mediators generated through several cascades as a result of surgical trauma to iris, ciliary body, or lens epithelial cells. So, the incidence of CME is increased by surgical complications, for example, vitreous loss. Moreover, pre-existing ocular conditions such as diabetes, hypertension, uveitis, and latanoprost drugs that affect blood–retinal barrier can increase the risk of CME[3].

Cataract in diabetic patients, with its high prevalence and earlier age of development, is considered as a major problem against adequate fundus examination and laser photocoagulation therapy in addition to decreased visual acuity[4].

Postoperative CME has been reported to have a strong association with non-insulin-dependent diabetes mellitus more than insulin-dependent diabetes mellitus. Many studies reported that retinopathy and macular changes in diabetic patients are accelerated by cataract surgery. However, other studies attributed this acceleration to natural course of diabetic disease[5].

Although fluorescein angiography is considered the gold standard for diagnosis of macular edema, quantification of fluorescein leakage is difficult. Optical coherence tomography (OCT) nowadays has an upper hand in diagnosis of macular edema because of its advantages as a noninvasive device and can detect macular edema quantitatively and qualitatively[6].

Recently, there is increased evidence that prostaglandins play a role in pathogenesis of changes of diabetic retinopathy and macular edema[7].

In spite of using corticosteroids as the gold standard in the treatment of ocular inflammation, it is associated with adverse effects that warrant their judicious use. Multiple adverse effects of topical steroids make them not safe for extended periods. Topical corticosteroid adverse effects include suppression of host immune response, which increases susceptibility to microbial infections, retardation of corneal epithelium and stromal wound healing, and rise in intraocular pressure (IOP)[8].

NSAIDs are potent anti-inflammatory medications that decrease proinflammatory prostaglandins by their inhibitory effect on cyclooxygenase[7].

The therapeutic efficacy of topical NSAIDs may have a role in the treatment of allergic conjunctivitis, postoperative inflammation, pain, and macular edema in addition to stability of intraoperative dilated pupil[8].

Intravitreal diclofenac may affect the treatment of diffuse diabetic macular edema up to 12 weeks with significant reduction in IOP, with comparable therapeutic effects to intravitreal triamcinolone on retinal thickness[9].

The aim of this study was to evaluate the prophylactic use of topical NSAIDs instead of topical steroids preoperatively and postoperatively to reduce the incidence of macular edema.


  Patients and Methods Top


This is a comparative prospective randomized clinical study. The sample size was calculated according to previous study results.

The study was approved by the ethical committee of Menoufia Faculty of Medicine, and an informed consent was obtained from all patients before the study was commenced. The study included 75 patients who visited the Outpatient Clinics of the Department of Ophthalmology, Menoufia University Hospitals, previously diagnosed as having cataract between January 2018 and December 2018.

Eligible 75 patients were randomly allocated into three equal groups (25 patients in each) by using a computer-generated list of random permutations according to the drugs that were used.

The study included all patients aged greater than 50 years who had phacoemulsification cataract extraction with intraocular posterior chamber (IOL) implantation.

Exclusion criteria included patients with one of the following: anterior segment pathology (e.g., corneal opacities, pseudoexfoliation, or dense cataract that interfere with OCT imaging), chronic or recurrent ocular inflammation, posterior segment pathology (e.g. history of macular edema, age-related maculopathy, diabetic retinopathy, retinal vascular disorders, or vetreoretinal interface), previous ocular trauma or intraocular surgery to the same eye, and systemic diseases (e.g. kidney, liver, and heart disease and chronic autoimmune diseases).

Placebo group (PL group, n = 25) included patients who received topical antibiotic four times per day starting 2 days before operation and ending 4 weeks after operation (control group).

Nepafenac group (NF group, n = 25) included patients who received 0.1% nepafenac eye drops three times per day starting 2 days before operation and ending 4 weeks after operation plus topical antibiotic.

Dexamethasone group (DEX group, n = 25) included patients who received 0.1% dexamethasone eye drops four times per day starting 2 days before operation and ending 4 weeks after operation plus topical antibiotic.

  1. Prophylactic topical antibiotic included moxifloxacin 0.3% eye drops QID on the day before the operative day
  2. The medications in the research study were started 2 days preoperatively:
  3. Pupil dilatation: one hour before surgery, the pupil was dilated with tropicamide 1%, cyclopentolate HCl 1%, and phenylephrine 2.5% every 15 min, 2 h preoperatively
  4. Anesthesia: the surgery was performed under local anesthesia: 2 ml of mepivacaine hydrochloride 3% as retrobulbar injection or subtenon injection
  5. Sterilization: (a) periocular skin sterilization was achieved by povidone iodine (betadine 10%), and (b) two drops of 5% povidone iodine solution were instilled in the conjunctival sac followed by irrigation with balanced salt saline after 1 min.


Surgical technique

All phaco-operations were performed by the same experienced surgeon (Professor Amin Faisal Ellakwa).

The standardized surgical technique was clear corneal incision, phacoemulsification using divide and conquer technique, and posterior chamber foldable IOL implantation into the capsular bag. Steps of phacoemulsification surgery were as follows: (a) intraocular povidone iodine drops administration; (b) the main and side port incisions; (c) viscoelastic injection; (d) anterior capsulorhexis; (e) hydrodissection and hydrodelineation; (f) divide and conquer technique; (g) irrigation and aspiration (I/A) of lens cortex; (h) IOL implantation in bag; and (i) wound hydration.

Postoperative care

Patients in all groups received standard regimen of topical steroid-antibiotic drops four times daily for a week and then tapered over the next 3 weeks. Eyes in the study groups received medication for 2 months as follows:

In group I, patients received topical antibiotic as placebo in the operative eye four times per day (morning, afternoon, evening, and before bedtime).

In group II, patients received nepafenac 0.1% one drop three times per day (morning, afternoon, and before bedtime) plus topical antibiotic.

In group III, patients received dexamethasone 0.1% one drop four times per day (morning, afternoon, evening, and before bedtime) plus topical antibiotic.

Postoperative follow-up was done as follows.

All patients were followed up postoperatively at first day, 1 week, 1 month, 2 months, and 3 months intervals:

  1. Postoperative follow-up on the first day was done using slit lamp regarding the following: state of the tunnel incision and side ports, state of the cornea including edema, signs of postoperative inflammation (anterior chamber cells, flare), the state of iris and pupil, PCIOL regarding its position and any deposits on its surface, and measurement of ocular tension using applanation tonometer. Any patient with postoperative pathology was excluded (sever corneal edema, AC flare and cells, abnormal IOL position, or abnormal IOP)
  2. Postoperative follow-ups at first week, first month, second month, and third month were done regarding the following: best-corrected visual acuity using chart of Landolt's broken rings, OCT to measure the macular thickness and anterior segment examination by slit lamp biomicroscopy.



  Results Top


The mean age of the nepafenac group was 60.43 years, whereas it was 59.23 years for the dexamethasone group. No statistically significant difference was found between the study groups regarding patient age (P > 0.05). Like age, sex was not statistically significant between the study groups (P = 0.362). The right eye was dominantly affected by cataract in our study groups (68, 72, and 72% for placebo, nepafenac, and dexamethasone groups, respectively). Most cataracts included in our study were classified as age related, whereas only three cases were caused by a different factor [Table 1].
Table 1: Demographic data of the cases included in study

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When it comes to the comorbidities, the incidence of diabetes and hypertension was not statistically significant among the study groups. The preoperative mean of BCVA was 1.56, 1.39, and 1.48 for placebo, nepafenac, and dexamethasone groups, respectively, and there was no significant difference between them (P = 0.433). Regarding central macular thickness, it was not statistically different among the study groups (P = 0.126) [Table 2].
Table 2: Preoperative data of the cases of the study groups

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The mean operative time was 11.32, 10.61, and 10.77 in the placebo group, nepafenac group, and dexamethasone group, respectively (P = 0.372). Neither the number of sutures nor the surgeon number was found to be significant between the study groups (P > 0.05) [Table 3].
Table 3: Assessment of the operative data of the cases of the study groups

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Despite being not statistically different from each other at the preoperative period, the central macular thickness showed improvement in the nepafenac and dexamethasone groups when compared with the placebo group at 1-week, 1-month, and 3-month follow-up visits. Despite the nepafenac group experiencing a smaller central macular thickness at these follow-up visits when compared with the dexamethasone group, there was no statistically significant difference between these two groups ([Table 4] and [Figure 1]).
Figure 1: Central macular thickness changes.

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Table 4: Analysis of complications in study groups

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BCVA between the study groups

During the postoperative follow-up visits, the study groups did not show significant difference when compared with each other (P > 0.05) [Figure 2].
Figure 2: Best-corrected visual acuity.

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When it comes to the postoperative complications, there was no significant difference among the three study groups (P > 0.05) [Table 4].


  Discussion Top


The study included 75 patients who visited the Outpatient Clinics of the Department of Ophthalmology, Menoufia University hospitals. The patients were subdivided into three groups, with 25 patients each, as follows: control group, nepafenac-treated group, and dexamethasone-treated group. In this study, the mean age of the nepafenac group was 60.43 years, whereas it was 59.23 years for the dexamethasone group. No statistically significant difference was found among the study groups regarding patient age. Like age, sex was not statistically significant among the study groups.

In this study, the central macular thickness showed improvement in the nepafenac and dexamethasone groups when compared with the placebo group at 1-week, 1-month, and 3-month follow-up visits. Despite the nepafenac group experiencing a smaller central macular thickness at these follow-up visits when compared with the dexamethasone group, there was no statistically significant difference between these two groups.

This was similar to another study that revealed that 10% of patients in control group had clinical CME with significant increase in macular thickness in comparison with NSAID groups. A higher incidence of increased CMT was noticed, as seen in 65% of patients in control group, 25% in nepafenac group, and 35% in ketorolac group[10].

Moreover, in consistence with these results, Wittpenn et al.[11] reported 11.5% of patients in control group had an increase in the foveal thickness (25–40 μm) and 8.4% in ketorolac group. They evaluated macular thickening in low risk patients for 4 weeks only and used NSAIDs four drops over 1 h preoperatively in both control and therapeutic groups to maintain mydriasis during surgery, which could explain the decrease in CME incidence in comparison with the current study.

In contrast to these results, Cervantes-Coste et al.[12] reported that the use of prophylactic ketorolac or nepafenac was not effective in the prevention of macular thickening after uneventful cataract surgery compared with placebo. In their study, macular thickness greater than 25 μm was reported in 7% of placebo group, 6% of nepafenac group, and 3% in ketorolac group[12].

When it comes to the comorbidities, the prevalence of diabetes and hypertension was not statistically significant between the study groups. The preoperative mean of BCVA was 1.56, 1.39, and 1.48, for placebo, nepafenac, and dexamethasone groups, respectively, and there was no significant difference among them. Regarding central macular thickness, it was not statistically different between the study groups.

The study did not show any significant difference regarding BCVA between the study groups during the post-operative follow-up visits, when compared with each other.

Our results came in agreement with Aboud (2018) who revealed that UCVA and BCVA improved significantly throughout the duration of follow-up in the patients included in their study; however, there was no statistically significant difference between ketorolac 4% plus steroid and steroid alone groups in UCVA or BCVA[13].

In consistence with these findings, Asano et al.[13] did not find any difference between both groups in visual acuity. Similar to the current study, Singh et al. reported that postoperative BCVA was affected in correlation with OCT macular thickness[14]. Cervantes-Coste et al.[12] documented that diclofenac effectively maintains mydriasis and decreases macular thickness[15],[16]. Moreover, diclofenac eye drops in Rossetti et al.[17] effectively reduced incidence of angiographic CME and ocular inflammation after cataract surgery.

Capote et al.[18] approved that bromfenac is more effective than diclofenac and nepafenac in reducing macular thickness after phacoemulsification. In other study, bromfenac was more effective and safer in comparison with topical steroid, in spite of using oral prednisolone for all patients in the study.

In other studies, NSAIDs did not seem to offer any additional benefit after uneventful phacoemulsification of diclofenac in the study of Moschos et al.[19] Miyanaga et al.[20] documented that 2-month use of topical NSAIDs, different topical steroids, or alternating steroids and NSAIDs had no significant differences.

In contrast, Endo et al.[21] preferred NSAIDs for visual acuity. Later, Kessel et al.[22] carried out a meta-analysis on four studies that reported the visual acuity at the longest follow-up (6–8 weeks) after cataract surgery, and concluded that NSAID groups achieved better BCVA.

In our study, there was no significant difference in the percentage of postoperative inflammation in the three groups.

This was in consistent with another study which also showed that both NSAIDS and steroids were effective in preventing anterior chamber flare, with no preference of any of them. In agreement with this, Holzer et al.[23] and Asano et al.[13] reached the same conclusion.

However, in the meta-analysis of Kessel et al.[22], the authors concluded that topical NSAIDs were more effective than steroid eye drops in reducing postoperative inflammation, measured as the amount of flare by laser flare photometry at 1 week postoperatively.

Results in two controlled studies[10],[24] confirm these properties of nepafenac; however, the studies evaluated nepafenac as a single treatment vs a placebo.

In another study, the results were variable as anterior segment inflammation on postoperative day 1 was significantly less in the nepafenac plus prednisolone group (group II) compared with prednisolone alone group. On day 7, three patients in prednisolone alone group and one in nepafenac plus prednisolone group had iritis, though the difference was not statistically significant[23].

Zaczek et al.[25] had compared nepafenac plus dexamethasone vs dexamethasone alone and had also found that addition of nepafenac reduced inflammation and subjective complaints.


  Conclusion Top


This study revealed the prophylactic effect of topical NSAIDs and steroids in reducing the frequency and severity of CME in patients undergoing cataract surgery and showed insignificant difference between the two modalities of treatment in the incidence and outcomes postoperatively.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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Mentes J, Erakgun T, Afrashi F, Kerci G. Incidence of cystoid macular edema after uncomplicated phacoemulsification. Ophthalmologica 2003; 217 :408–412.  Back to cited text no. 1
    
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Shahidi M, Ogura Y, Blair NP, Rusin MM, Zeimer RJ. Retinal thickness analysis for quantitative assessment of diabetic macular edema. Arch Ophthalmol 1991; 109 :1115–1119.  Back to cited text no. 4
    
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Flesner P, Sander B, Henning V, Parving HH, De La Cour MD, Lund Andersen HJ. Cataract surgery on diabetic patients. A prospective evaluation of risk factors and complications. Acta Ophthalmol Scand 2002; 80 :19–24.  Back to cited text no. 5
    
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11.
Wittpenn JR, Silverstein S, Heier J, Kenyon KR, Hunkeler JD, Earl M, et al. A randomized, masked comparison of topical ketorolac 0.4% plus steroid vs steroid alone in low-risk cataract surgery patients. Am J Ophthalmol 2008; 146 :554–560.  Back to cited text no. 11
    
12.
Cervantes-Coste G, Sánchez-Castro YG, Orozco-CarrollM, Mendoza-Schuster E and Velasco-Barona, C. Inhibition of surgically induced miosis and prevention of postoperative macular edema with nepafenac. Clin Ophthalmol 2009; 3 :219.  Back to cited text no. 12
    
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Asano S, Miyake K, Ota I, Sugita G, Kimura W, Sakka Y, Yabe N. Reducing angiographic cystoid macular edema and blood-aqueous barrier disruption after small-incision phacoemulsification and foldable intraocular lens implantation: multicenter prospective randomized comparison of topical diclofenac 0.1% and betamethasone 0.1%. J Cataract Refract Surg 2008; 34 :57–63  Back to cited text no. 13
    
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Singh R, Alpern L, Jaffe GJ, Lehmann RP, Lim J, Reiser HJ, et al. Evaluation of nepafenac in prevention of macular edema following cataract surgery in patients with diabetic retinopathy. Clin Ophthalmol 2012; 6:1259.   Back to cited text no. 14
    
15.
Wang Q, Yao K, Xu W, Chen P, Shentu X, Xie X, et al. Bromfenac sodium 0.1%, fluorometholone 0.1% and dexamethasone 0.1% for control of ocular inflammation and prevention of cystoid macular edema after phacoemulsification. Ophthalmologica 2013; 229 :187–194.  Back to cited text no. 15
    
16.
Moschos MM, Chatziralli IP, Pantazis P, Rouvas AA, Sergentanis TN. Is topical diclofenac essential before and after uneventful phacoemulsification cataract surgery?. J Ocular Pharmacol Ther 2012; 28 :335–339.  Back to cited text no. 16
    
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18.
Capote AM, Soto ML, Ruiz FR, Peláez EC, Vazquez AG, OftaCosta G, et al. Comparative study of the efficacy and safety of bromfenac, nepafenac and diclofenac sodium for the prevention of cystoid macular edema after phacoemulsification. Int J Ophthalmol 2018; 11 :1210.  Back to cited text no. 18
    
19.
Moschos MM, Chatziralli IP, Pantazis P, Rouvas AA, Sergentanis TN. Is topical diclofenac essential before and after uneventful phacoemulsification cataract surgery?. J Ocular Pharmacol Ther 2012; 28 :335–339.  Back to cited text no. 19
    
20.
Miyanaga M, Miyai T, Nejima R, Maruyama Y, Miyata K, Kato S. Effect of bromfenac ophthalmic solution on ocular inflammation following cataract surgery. Acta ophthalmol 2009; 87 :300–305.   Back to cited text no. 20
    
21.
Endo N, Kato S, Haruyama K, Shoji M, Kitano S. Efficacy of bromfenac sodium ophthalmic solution in preventing cystoid macular oedema after cataract surgery in patients with diabetes. Acta ophthalmol 2010; 88 :896–900.   Back to cited text no. 21
    
22.
Kessel L, Tendal B, Jørgensen KJ, Erngaard D, Flesner P, Andresen JL, et al. Post-cataract prevention of inflammation and macular edema by steroid and nonsteroidal anti-inflammatory eye drops: a systematic review. Ophthalmology 2014; 121 :1915–1924.  Back to cited text no. 22
    
23.
Hozler MP, Solomon KD, Sandoval HP, Vroman DT. Comparison of ketorolac tromethamine 0.5% and loteprednol etabonate 0.5% for inflammation after phacoemulsification: prospective randomized double-masked study. J Cataract Refract Surg 2002; 28 :93–99.  Back to cited text no. 23
    
24.
Zaczek A, Artzen D, Laurell CG, Stenevi U, Montan P. Nepafenac 0.1% plus dexamethasone 0.1% versus dexamethasone alone: effect on macular swelling after cataract surgery. J Cataract Refract Surg 2014; 40 :1498–1505.  Back to cited text no. 24
    
25.
Zaczek A, Artzen D, Laurell CG, Stenevi U, Montan P: Nepafenac 0.1% plus dexamethasone 0.1% versus dexamethasone alone: effect on macular swelling after cataract surgery. J Cataract Refract Surg. 2014; 40 :1498–505. doi: 10.1016/j.jcrs.2013.12.023.  Back to cited text no. 25
    


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