Drop-Free Approaches for Cataract Surgery

Abstract and Introduction

Abstract

Purpose of review: Routine prophylaxis for adverse events following cataract surgery is evolving. Prior reliance on topical eyedrop instillation by patients is giving way to surgeon directed injections at the time of cataract surgery. The benefit of this new approach is assured delivery of drugs in standardized doses which should optimize the healing process and reduce the incidence of untoward events with higher confidence.

Recent findings: Adoption rates of intracameral antibiotic injection amongst European and American cataract surgeons is increasing. Techniques to inject periocular corticosteroid for routine inflammation prophylaxis are also in development. In combination with intraoperative pharmacologic dilation, a drop-free modality can be achieved.

Summary: Intraoperative injections offer the patient and surgeon assured drug delivery and hold promise to avoid the pitfalls of patient adherence, incorrect topical instillation, and topical drop-associated corneal issues.

Introduction

The prior worldwide standard practice for prophylaxis against postoperative infections and inflammation following cataract surgery, and for iris dilation, has involved the application of perioperative eyedrops. Topical drop instillation may have inherent drawbacks including patient adherence, cost, and negative impact on the environment from single-use, plastic containers.

Early work on injectable drugs dates back to the late 1960s^[1,2] when the first steroids were injected for inflammation control following cataract surgery. In the decades that followed, the first antibiotics were injected or added to irrigating solutions to help prevent endophthalmitis.^[3,4]

Barriers to the adoption of injection regimens have been a perceived lack of evidence of safety and effectiveness, absence of government-approved, manufactured products, risk of contamination or dilution error from compounded products, and cost.^[5] This review will consider replacement of eyedrops in favor of injectable drugs in the following three areas: pharmacologic iris dilation; endophthalmitis prophylaxis; and suppression of inflammation, prevention of pain, and postoperative cystoid macular edema (CME) following cataract surgery.

Table 1. Potential eye drop risks
Drug exposure failure	Prescribing error
	Prescription not filled by patient
	Failure to instill the drops
	Discontinuing prematurely
Contamination	Eyelid/lash touch to dropper tip
	Poor hand hygiene
Microtrauma to eye	Corneal abrasion
	Conjunctival abrasion

Table 2. Studies of triamcinolone acetonide injection at the conclusion of cataract surgery
Author	Dose (mg)	Location	Topical comparison	Inflammation in injection group	IOP in injection group
Paganelli [62]	40	PST	PA	Same	Lower
Negi [63]	20–30	PST	BM	Same	Same
Shorstein [18]	2	Subconjunctival	PA	Same	Same
PREMED [64]	40	Subconjunctival	DX þ BF	Lower CST	Higher
Rattan [65]	4	Subconjunctival	DX	Same	Lower
Lindholm [66]	20	Subconjunctival	DX	Lower CST	Same

BF, Bromfenac; BM, betamethasone; CST, central subfield macular thickness on optical coherence tomography; DX, dexamethasone; IOP, intraocular pressure; PA, prednisolone acetate; PST, posterior subtenons.