Intravitreal (IVT) injection is the most common ophthalmic procedure performed in the United States today; the annual number will soon be double that of cataract surgeries. On the 10th anniversary of the 2004 publication of the original IVT injection guidelines,1 an expert panel convened to update the guidelines on injection technique and monitoring. The complete 2014 guidelines are available in Retina.2
Role of antibiotics. The first significant change is a move away from the use of pre-, peri- and postinjection antibiotics intended to minimize endophthalmitis risk. A growing body of evidence has deemed such antibiotics unnecessary, and eliminating their use represents a huge cost savings and reduction in patient burden before and after the procedure, according to Harry W. Flynn Jr., MD, the J. Donald M. Gass Chair of Ophthalmology and professor of ophthalmology at the Bascom Palmer Eye Institute in Miami.
Contaminated droplets. A major addition to the guidelines is an emphasis on limiting the spread of aerosolized droplets from the mouth of the patient or medical staff by using surgical masks or refraining from talking during the procedure. This change was prompted by a growing body of evidence implicating oral contaminants as a potential source of injection-related endophthalmitis.
Use of povidone-iodine. In addition, consensus has grown even stronger regarding several recommendations that were included in the 2004 guidelines. Most notable are the importance of applying povidone-iodine to the site before the injection and the recognition that the eyelids are a major potential source of contamination.
“These aspects of IVT injection technique were universally agreed upon by the panel and continue to be essential to proper technique,” said Emmett T. Cunningham Jr., MD, PhD, MPH, Director of the Uveitis Service at California Pacific Medical Center in San Francisco, adjunct clinical professor of ophthalmology at Stanford University School of Medicine, and research associate at the Francis I. Proctor Foundation, UCSF School of Medicine.
He added that povidone-iodine (5-10 percent) should be the last agent applied to the intended injection site before injection. If a gel anesthetic is used, however, povidone-iodine should be applied both before and after the gel because, said Dr. Cunningham, “gel applied prior to povidone-iodine may prevent the povidone-iodine from contacting the conjunctival surface, thereby decreasing its effectiveness.
Other changes. Dr. Flynn noted two other changes to the guidelines that he considers particularly significant. First, there was concern in 2004 that the use of anticoagulation therapy may increase the risk of intraocular bleeding complications during or after an IVT injection. Clinical experience indicates no difference in the rate between patients using or not using systemic anticoagulants.
Second, past concerns about allergic reactions to povidone-iodine were overblown. “Many patients will give a history of an allergy to shellfish or an iodine dye they may have received in the past. There has been no reported anaphylaxis after the use of topical ophthalmic povidone-iodine,” said Dr. Flynn. “Even though patients may occasionally have swelling or redness after the use of povidone-iodine, the benefit in terms of killing bacteria far outweighs the localized swelling after the procedure.” Patients with previous anaphylactic reaction to iodine can be referred to an allergist, the guidelines advise.
1 Aiello LP et al. Retina. 2004; 24(5 suppl):S3-S19.2 Avery RL et al. Retina. 2014; 34(12):S1-S18.
Drs. Flynn and Cunningham report no related financial interests.
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