Post-cataract surgery eye drops

Key Points at a Glance

Post-cataract surgery eye drops consist of four categories: antibiotics, steroids, NSAIDs, and dry eye treatments.
Intracameral cefuroxime injection (1 mg/0.1 mL) has the strongest evidence for preventing endophthalmitis. ¹⁾²⁾
Combined use of NSAIDs and steroids is recommended for prevention of cystoid macular edema (CME) (GRADE +/++). ¹⁾
In diabetic patients, combined NSAIDs and steroids can prevent 75.8% of postoperative CME. ⁸⁾
Preservative-free artificial tears are the first choice for postoperative dry eye.
Drop-less cataract surgery is a strategy that omits eye drops by intraoperative intracameral, subconjunctival, or sub-Tenon administration, and is considered useful for patients with poor eyedrop adherence. ¹⁾³⁾
The optimal drug, dosage, and route of administration have not been established and are being investigated in the ESCRS EPICAT trial. ¹⁾

1. Purpose and significance of postoperative eyedrops after cataract surgery

Cataract affects an estimated 95 million people worldwide, and approximately 10 million surgeries are performed annually. Cataract surgery is one of the most common outpatient procedures globally. Multiple topical eyedrops are prescribed to prevent postoperative complications.

The main postoperative complications are as follows:

Postoperative corneal edema: Corneal endothelial damage due to surgical trauma
Cystoid macular edema (CME): Clinically significant incidence up to 2%¹⁾. Most cases resolve spontaneously, but persistence can lead to visual impairment¹⁾
Postoperative endophthalmitis: Incidence 0.006–0.04%. Can lead to severe vision loss
Postoperative dry eye: Caused by corneal nerve damage, intraoperative drying, and toxicity of eye drops

The main drug classes for postoperative eye drops are topical antibiotics, topical steroids, and topical NSAIDs. Data supporting optimal postoperative eye drop regimens are limited, and drug selection varies among surgeons.

Q What types of eye drops are used after cataract surgery?

Four main categories of eye drops are used: antibiotics to prevent endophthalmitis, NSAIDs to prevent cystoid macular edema, steroids to control inflammation, and artificial tears or cyclosporine for postoperative dry eye.

Clinical Findings of Postoperative Complications

The postoperative evaluation items are as follows.

Anterior chamber cells and flare: Indicators of anterior chamber inflammation. The NSAIDs group showed significantly less flare at 1 week postoperatively compared to the steroid-only group¹⁾
Corneal edema: Caused by corneal endothelial damage due to surgical trauma
Cystoid macular edema: Cystic thickening of the macula. Often develops 1 to 3 months postoperatively
Eyelid edema, conjunctival injection, and ciliary injection: Associated with postoperative inflammation
Dry eye findings: Tear film instability, corneal epithelial damage

Evaluation tests are as follows:

OCT (Optical Coherence Tomography): Used to diagnose cystoid macular edema, quantitatively assessing central retinal thickness (CRT)
Slit-lamp microscopy: Quantifies anterior chamber cells and flare to assess the degree of inflammation
Intraocular pressure measurement: Detects steroid-induced intraocular pressure elevation
Tear film tests: Dry eye evaluation using tear break-up time (BUT) and Schirmer test

2. Antibiotic Eye Drops

The protocol for preventing postoperative endophthalmitis combines multiple measures. Topical antibiotic eye drops are adjunctive, with povidone-iodine disinfection and intracameral antibiotic administration forming the foundation of prevention.

Preoperative povidone-iodine disinfection: Apply 5–10% povidone-iodine to the cornea, conjunctival fornix, and periorbital skin at least 3 minutes before surgery. This is an established method for infection prevention¹⁾
5% povidone-iodine conjunctival sac instillation: Evidence shows it reduces bacterial load and decreases the incidence of postoperative infection²⁾
Intracameral cefuroxime injection (1 mg/0.1 mL): Efficacy was demonstrated in a large prospective RCT by ESCRS¹⁾²⁾. Intracameral administration delivers higher drug concentrations to the surgical site than topical administration, resulting in greater bactericidal activity²⁾
Postoperative topical antibiotic eye drops: When intracameral antibiotics are used, the additional benefit of postoperative eye drops in reducing endophthalmitis incidence is unclear⁴⁾. However, some reports indicate a reduction in conjunctival sac bacterial load at 1 week postoperatively⁵⁾
Preoperative topical antibiotics: There are reports that they reduce Staphylococcus epidermidis in the conjunctival sac⁶⁾. The evidence for directly reducing the incidence of endophthalmitis is not as strong as for intracameral administration.
Consideration of resistant bacteria: Levofloxacin eye drops reduce bacterial load but may promote the selection of highly resistant strains⁵⁾.

The first choice for typical postoperative topical antibiotics is the fourth-generation fluoroquinolones (gatifloxacin, moxifloxacin).

Q Which is more effective: postoperative topical antibiotics or intracameral antibiotic injection?

Intracameral cefuroxime injection (1 mg/0.1 mL) has the most established evidence for directly reducing the incidence of endophthalmitis²⁾. Pre- and postoperative topical antibiotics are an adjunctive measure to reduce the bacterial load on the ocular surface, but a consistent additive benefit over intracameral administration has not been demonstrated⁴⁾⁵⁾.

3. Steroid eye drops

Steroids are used for both prevention of cystoid macular edema and suppression of postoperative inflammation.

Main drugs: Prednisolone 1%, Rimexolone 1%, Loteprednol 0.5%, Difluprednate 0.05%, Betamethasone
Difluprednate 0.05%: Prophylactic use starting 24 hours before surgery is effective for postoperative inflammation and pain management
Prednisolone 1% vs Rimexolone 1%: Rimexolone has a lower tendency to increase intraocular pressure compared to prednisolone
Characteristics of steroids: More rapid effect than NSAIDs in reducing anterior chamber cell count. Particularly effective for suppressing inflammation in cases with uveitis

Steroids inhibit phospholipase A2 (PLA2) and suppress the entire arachidonic acid cascade, thereby exerting a broad anti-inflammatory effect.

Precautions

Increased intraocular pressure: Postoperative steroid eye drops can cause elevated intraocular pressure. Regular intraocular pressure measurement is necessary, especially in young patients, high myopes, and glaucoma patients.
Steroid responders: The risk of steroid response is high in patients under 51 years of age and those with an axial length of 29.0 mm or more.
Effects of long-term use: There is a risk of promoting infections and accelerating posterior subcapsular cataract.

4. NSAIDs Eye Drops

NSAIDs are used to maintain intraoperative mydriasis and prevent cystoid macular edema. They inhibit cyclooxygenase (COX) and suppress prostaglandin synthesis.

Comparison of representative NSAID eye drops:

Drug name	Concentration	Dosage
Bromfenac	0.09%	Twice daily
Nepafenac	0.1%	3 times daily
Ketorolac	—	4 times daily
Diclofenac	—	4 times daily

The recommended schedule is to start the day before surgery and continue for 4 weeks postoperatively. During surgery, instill drops every 15 minutes starting 1 hour before the procedure.

Evidence for NSAID and steroid combination (ESCRS guidelines)

NSAIDs vs steroids (CME incidence): The incidence of CME at 1 month postoperatively is lower in the NSAID-only group (RR 0.26, 95% CI 0.17–0.41)¹⁾
NSAIDs + steroids vs steroids alone (CME incidence): RR 0.40 (95% CI 0.32–0.49, 21 trials, n=3,638 eyes) ¹⁾
NSAIDs + steroids vs steroids alone (risk of poor visual acuity at 3 months): RR 0.41 (95% CI 0.23–0.76, 5 trials, n=1,360 eyes) ¹⁾
NSAIDs + steroids vs steroids alone (change in macular volume): MD −0.14 (95% CI −0.21 to −0.07, 6 trials, n=570 eyes), favoring combination therapy ¹⁾
NSAIDs vs placebo (incidence of macular edema at 3 months): RR 0.26 (95% CI 0.15–0.43) ¹⁾

In the ESCRS PREMED RCT, the combination of bromfenac 0.09% twice daily plus dexamethasone 0.1% four times daily showed a lower incidence of CME than either agent alone ²⁾.

Combination of NSAIDs and steroids is recommended (GRADE +/++) ¹⁾. NSAIDs or steroid eye drops are positioned as first-line treatment for CME ¹⁾.

NSAIDs and steroids act synergistically by inhibiting different stages of the arachidonic acid metabolic cascade.

Property	NSAIDs	Steroids
Target enzyme	COX	PLA2
Inhibition pathway	PG synthesis	All AA pathways

Precautions

Corneal melting: Use of NSAIDs in the presence of corneal epithelial defects carries a risk of corneal melting.
Exacerbation of postoperative dry eye: NSAID eye drops may worsen postoperative dry eye and corneal hypoesthesia.

5. Postoperative Eye Drop Regimen and Duration

Antibiotics

Purpose: Prevention of postoperative endophthalmitis

First choice: Fourth-generation fluoroquinolone

Position: Intracameral cefuroxime injection has the strongest evidence. Postoperative topical eye drops are an adjunctive measure¹⁾⁴⁾

NSAIDs

Purpose: Maintain intraoperative mydriasis and prevent CME

Main drugs: Bromfenac 0.09%, Nepafenac 0.1%, Ketorolac

Recommendation: Combination with steroids most reduces CME incidence¹⁾

Steroids

Purpose: Suppress postoperative inflammation and prevent CME

Main drugs: Prednisolone 1%, Rimexolone 1%, Loteprednol 0.5%

Prescription period: Usually 2–6 weeks after surgery

Dry Eye Treatment

Purpose: Relief of postoperative dry eye symptoms

First choice: Preservative-free artificial tears, gels, and ointments

Second choice: Topical cyclosporine

Special Management for Diabetic Patients

NSAIDs + Steroids

Recommendation level: First choice¹⁾

Effect: Prevents 75.8% of postoperative CME (compared to steroids alone)⁸⁾

Evidence: OR 0.17 (95% CI 0.05–0.50)⁸⁾

Depot Steroid

Indication: Consider in patients with diabetic retinopathy¹⁾

Drug: Subconjunctival injection of triamcinolone acetonide (single dose)¹⁾

Caution: Increased risk of elevated intraocular pressure¹⁾

Anti-VEGF

Current status: Insufficient evidence to support regular use¹⁾

Issues: The anti-VEGF group had a significantly higher incidence of macular edema than the NSAID eye drop group (RR 2.31, 95% CI 1.04–5.14)¹⁾

Conclusion: Regular use is not recommended¹⁾

Additional evidence in diabetic patients is as follows.

Combination of steroid + NSAIDs prevents 75.8% of PCME events (compared to steroid alone) ⁸⁾
Depot steroid (triamcinolone) + topical steroid is superior to topical steroid alone, but the incidence of intraocular pressure elevation increases ¹⁾
Intravitreal injection of bevacizumab 1.25 mg does not significantly reduce postoperative macular thickness or macular volume in diabetic patients ¹⁾

Topical dry eye treatment

First-line: preservative-free artificial tears, gels, ointments
Second-line: topical cyclosporine for 2–4 weeks (suppresses ocular surface inflammation and improves lacrimal gland function)
Additional therapeutic agents: diquafosol sodium (P2Y2 receptor agonist, increases mucin secretion), rebamipide (increases mucin secretion). Both reduce symptoms and incidence of dry eye after cataract surgery.

Postoperative management in complicated cases

In complicated cases such as posterior capsule rupture or extra-capsular lens placement, postoperative inflammation is more severe and prolonged.

Examine within 24 hours after surgery, then follow up frequently thereafter.
The topical regimen is the same as for routine cases (NSAIDs + steroids + antibiotics).
Miosis cases: Add pilocarpine 1–2% for 1–2 weeks

Q How often does cystoid macular edema occur after cataract surgery?

The incidence of clinically significant cystoid macular edema has been reported to be up to 2% ¹⁾. Most cases resolve spontaneously, but if prolonged, it can lead to visual impairment. The combination of NSAIDs and steroids significantly reduces the incidence ¹⁾.

Q Is special consideration needed for postoperative eye drops in cataract surgery for diabetic patients?

In diabetic patients, the combination of NSAIDs and steroids is strongly recommended. This combination can prevent 75.8% of postoperative cystoid macular edema compared to steroids alone ¹⁾. In cases with diabetic retinopathy, subconjunctival injection of triamcinolone acetonide may be considered as an adjunct, but it carries a risk of increased intraocular pressure ¹⁾.

6. Overview of Dropless Strategy

Dropless cataract surgery is a method that omits postoperative eye drops and injects anti-inflammatory and antimicrobial agents intraocularly or periocularly during surgery. It is positioned as an option for patients expected to have poor adherence to eye drops ¹⁾.

Background Factors for Difficulty with Eye Drops

Physical factors: Arthritis, decreased manual dexterity, tremor
Cognitive factors: Cognitive impairment, memory impairment
Social factors: Lack of caregiver, elderly living alone
Economic factors: Cost burden of eye drops

Route of Administration

Subconjunctival Injection

Administration site: Subconjunctival (bulbar or palpebral)

Advantages: Minimally invasive. If postoperative intraocular pressure elevation occurs, the depot can be removed by conjunctival resection.

Drug examples: Triamcinolone acetonide (TA) 2–5 mg, betamethasone acetate 5.7 mg/mL¹⁾

Sub-Tenon injection

Administration site: Sub-Tenon space between Tenon’s capsule and the sclera

Drug examples: TA 20–40 mg¹⁾

Caution: Visualization of the needle tip and monitoring of the depot are slightly more difficult than with subconjunctival injection.

Intravitreal Injection

Injection site: Center of the vitreous cavity through the pars plana.

Advantages: Can directly prevent retinal inflammation.

Risks: Complications in the retina can be more severe than with other routes of administration.

Intracameral Antibiotic Administration

Intracameral administration of antibiotics during surgery has been shown to be effective in preventing postoperative endophthalmitis ²⁾.

Cefuroxime: Standard drug for intracameral administration. In the ESCRS multicenter prospective randomized trial (16,603 cases), the risk of endophthalmitis increased 4.92-fold (95% CI 1.87-12.9) in the group that did not receive intracameral cefuroxime 1 mg/0.1 mL ¹⁾
Moxifloxacin: In the United States, preservative-free 0.5% moxifloxacin is most commonly used. Intracameral administration significantly reduced the incidence of endophthalmitis (OR 0.29; 95% CI 0.15-0.56) ¹⁾

In a retrospective study of 315,246 cataract surgeries, intracameral antibiotic administration was more effective in preventing endophthalmitis than topical antibiotics alone ²⁾. When intracameral antibiotics were not used, the RR of endophthalmitis was 2.94 (95% CI 1.07-8.12) ¹⁾.

Three-step approach to disinfection and infection prevention

A three-step approach to endophthalmitis prevention has been proposed ¹⁾.

Ocular surface disinfection: Apply 5–10% povidone-iodine to the cornea, conjunctival fornix, and periorbital skin 3 minutes before surgery. There is also a method (Shimada method) of irrigating with 0.25% povidone-iodine every 20–30 seconds during surgery¹⁾
Anterior chamber irrigation: Wash out bacteria that have entered the anterior chamber by irrigation
Antibiotic administration: Administer intracameral antibiotics at the end of surgery

Pharmacokinetics

Intracameral antibiotic administration: The intracameral route delivers much higher drug concentrations to the surgical site compared to eye drops, resulting in higher bactericidal activity²⁾
Depot steroids: Triamcinolone injected subconjunctivally or under the Tenon capsule forms a depot and slowly releases into the eye. Low concentration and high volume (TA 10 mg/mL) cover a large surface area and disappear more quickly via scleral diffusion, conjunctival lymphatics, and blood vessels
Risk of intraocular pressure elevation: Depot steroids are more difficult to remove than eye drops, and intraocular pressure elevation may be prolonged¹⁾

7. Evidence for dropless therapy

Intracameral antibiotics and postoperative eye drops

Recent meta-analyses have shown that when intracameral antibiotics are used, adding postoperative antibiotic eye drops does not clearly reduce the incidence of endophthalmitis⁴⁾. However, preoperative and postoperative eye drops help reduce the bacterial load on the ocular surface⁵⁾⁶⁾. The decision to adopt a dropless approach should consider patient risk, wound status, eye drop adherence, and the risk of antibiotic resistance⁵⁾.

Dose optimization of subconjunctival triamcinolone

Shorstein et al. (2024) compared four triamcinolone injection groups and two eye drop groups⁷⁾. When TA 10 mg/mL was injected at 4 mg into the subconjunctival space 6–8 mm from the inferior corneal limbus, the incidence of postoperative macular edema and iritis was low, and glaucoma-related events were similar to the eye drop groups. In contrast, the TA 40 mg/mL group had a statistically higher incidence of glaucoma events.

This result suggests that subconjunctival injection at a low concentration and appropriate dose is promising.

Intracameral Drug Delivery System

Dexycu: An intracameral dexamethasone sustained-release suspension that gradually releases the drug with a single injection. It has been reported to be more effective than eye drops in controlling inflammation after vitreoretinal surgery. However, iris atrophy after routine cataract surgery has been reported, and safety confirmation is ongoing.
Dextenza: A 0.4 mg dexamethasone sustained-release insert placed in the lacrimal canaliculus, releasing the drug for up to 30 days. Compared with steroid tapering eye drops, no significant differences were observed in breakthrough inflammation, intraocular pressure changes, cystoid macular edema, or pain.

Intravitreal Combination Formulations such as Tri-Moxi

Intravitreal combination formulations such as Tri-Moxi (triamcinolone + moxifloxacin) and Tri-Moxi-Vanc are also being investigated. They have the advantage of using the vitreous cavity as a drug reservoir. However, formulations containing vancomycin pose a risk of hemorrhagic occlusive retinal vasculitis (HORV). Large-scale randomized trials are also lacking.

ESCRS EPICAT Study

ESCRS is planning the EPICAT (Effectiveness of Periocular drug Injection in CATaract surgery) study to elucidate the optimal strategy for dropless cataract surgery ¹⁾. Currently, the optimal drug, dose, and route of administration have not been defined, and the results of this study are expected to influence future clinical guidelines.

8. Benefits, Challenges, and Complications

Benefits of Dropless Surgery

Reduces the burden of eye drops on patients
Expected to improve treatment outcomes in patients with poor adherence to eye drops
May help reduce financial burden
Highly practical for elderly patients, those with dementia, or those with difficulty in assisted care

Complications and Precautions

Complications to be aware of after dropless surgery are as follows:

Toxic anterior segment syndrome (TASS): Sterile inflammation limited to the anterior segment occurring 12–48 hours postoperatively. Presents with extensive corneal edema, fibrinous reaction in the anterior chamber, and hypopyon. Usually confined to the anterior segment and resolves with steroid eye drops.
Endophthalmitis: Inflammation extends to both the anterior and posterior chambers. Differentiated by culture testing. Requires tap and inject or vitrectomy.
Toxic posterior segment syndrome (TPSS): Progressive toxic maculopathy reported after intravitreal injection of a triamcinolone-moxifloxacin combination. OCT shows thinning of the outer retinal layers.

Condition	Onset time	Features
Postoperative anterior segment toxic syndrome	12–48 hours postoperatively	Sterile inflammation limited to the anterior segment
Endophthalmitis	A few days after surgery	Inflammation of the anterior and posterior chambers
Toxic posterior segment syndrome (TPSS)	About 3 months after surgery	Painless vision loss

Periocular injection of depot steroids carries a risk of prolonged intraocular pressure elevation compared to eye drops. If intraocular pressure elevation persists beyond 1 month postoperatively, additional monitoring is recommended¹⁾.
Intracameral vancomycin is associated with hemorrhagic occlusive retinal vasculitis (HORV), which can lead to severe vision loss.
Use of compounded triamcinolone-moxifloxacin preparations carries a risk of toxic posterior segment syndrome (TPSS)²⁾. It is necessary to confirm that the compounding process does not include potentially toxic compounds.
Overdose of cefuroxime can cause corneal and retinal toxicity²⁾.
Intracameral antibiotics should be used after confirming their approval status and preparation safety.

Q How to differentiate TASS from endophthalmitis?

TASS is a sterile inflammation that occurs within 12 to 48 hours after surgery and is limited to the anterior segment. In contrast, endophthalmitis involves inflammation in both the anterior and posterior chambers and is often associated with infection. Differentiation is made by culture tests and clinical course. TASS usually improves with steroids, while endophthalmitis requires tap and inject or vitrectomy.

9. Patient Selection and Clinical Decision-Making

Candidates for Dropless Surgery

Dropless surgery is particularly considered in the following patients.

Patients with hand function impairment such as arthritis or Parkinson’s disease.
Patients with cognitive or memory impairment who are expected to forget eye drops
Elderly patients living alone without a caregiver
Patients who cannot afford the cost of eye drops
Patients with a history of poor adherence to eye drops

Patients Requiring Careful Consideration

In the following patients, the risks of a dropless strategy may outweigh the benefits.

Steroid responders/glaucoma patients: High risk of intraocular pressure elevation
Young patients (under 51 years): High risk of steroid response
High myopia (axial length ≥29.0 mm): High risk of steroid response
High-risk cases with posterior capsule rupture/vitreous prolapse: Adjunctive eye drops are desirable
Patients with diabetic retinopathy: High risk of CME, may require additional NSAID eye drops

Key Points for Clinical Judgment

Complete dropless or partial omission: Stepwise omission is also an option, such as intracameral antibiotics only and continued steroid eye drops.
Enhanced postoperative follow-up: In cases with omitted eye drops, check inflammation and intraocular pressure at postoperative day 1, week 1, and month 1.
Patient education: Emphasize immediate consultation if eye pain or sudden vision loss occurs.
Facility protocol: Safety of drug preparation and collaboration with pharmacists are prerequisites.

Q Which is better: dropless surgery or conventional eye drop therapy?

At present, it is unclear whether dropless surgery is as safe and effective as conventional eye drop therapy¹⁾. Although suppression of general postoperative inflammatory indicators (flare) has been reported to be equivalent, results regarding prevention of cystoid macular edema are inconsistent. For patients with expected good adherence to eye drops, combined use of NSAIDs and steroid eye drops is recommended¹⁾.

Q Can eye drops after cataract surgery be omitted in the future?

There are studies showing that intracameral administration alone can maintain a low infection rate. However, there is insufficient evidence that eye drops can be omitted in all cases. It is important to make individual decisions based on the burden of eye drops, wound condition, infection risk, and risk of resistant bacteria.

10. References

European Society of Cataract and Refractive Surgeons (ESCRS). ESCRS Recommendations for Cataract Surgery. ESCRS; 2024. https://www.escrs.org/escrs-recommendations-for-cataract-surgery.
American Academy of Ophthalmology (AAO). Cataract in the Adult Eye Preferred Practice Pattern. Ophthalmology. 2022;129(4):S1-S126.
Lindstrom RL, Galloway MS, Grzybowski A, Liegner JT. Dropless cataract surgery: an overview. Curr Pharm Des. 2017;23(4):558-564. PMID: 27897120. doi:10.2174/1381612822666161129150628.
Passaro ML, Posarelli M, Avolio FC, Ferrara M, Costagliola C, Semeraro F, et al. Evaluating the efficacy of postoperative topical antibiotics in cataract surgery: A systematic review and meta-analysis. Acta Ophthalmol. 2025;103(6):622-633. doi:10.1111/aos.17469. PMID:40018950.
Matsuura K, Miyazaki D, Inoue Y, Sasaki Y, Shimizu Y. Comparison of iodine compounds and levofloxacin as postoperative instillation; conjunctival bacterial flora and antimicrobial susceptibility following cataract surgery. Jpn J Ophthalmol. 2024;68(6):702-708. doi:10.1007/s10384-024-01117-8. PMID:39240403.
Totsuka N, Koide R. The effect of preoperative topical antibiotics in cataract surgery. Nippon Ganka Gakkai Zasshi. 2006;110(7):504-510. PMID:16884070.
Shorstein NH, McCabe SE, Alavi M, Kwan ML, Chandra NS. Triamcinolone acetonide subconjunctival injection as stand-alone inflammation prophylaxis after phacoemulsification cataract surgery. Ophthalmology. 2024;131(10):1145-1156. PMID: 38582155. PMCID: PMC11416342. doi:10.1016/j.ophtha.2024.03.025.
Laursen SB, Erngaard D, Madi HA, et al. Prevention of macular edema in patients with diabetes after cataract surgery. J Cataract Refract Surg. 2019;45(6):854-869. doi:10.1016/j.jcrs.2019.04.025.

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