Study: Intravitreal injection needles could pose risk for infection

Bacteria found on needles after injection of intravitreal drugs could be linked to postoperative endophthalmitis, a study found.

While the contamination rate was low, the bacteria are still of concern in intravitreal procedures because of the potential for infection, study authors said.

"[Intravitreal] injection needles became contaminated with bacteria during the injection procedure. ... [T]his supports a mechanism of postinjection endophthalmitis in which there is direct inoculation of ocular surface flora into the vitreous cavity by the injection needle," they said.

Christopher N. Ta, MD, and colleagues studied 104 patients, with 118 intravitreal injection procedures performed on 107 eyes, at the California Vitreoretinal Center and the Vantage Eye Center. They used standard microbiological techniques to culture, identify and quantify bacterial contamination of the injection needles and the bulbar conjunctiva.

They found that two of the 114 needles collected had been contaminated with bacteria. Coagulase-negative Staphylococcus was found on the culture-positive needles, the researchers said.

Before prophylaxis with topical antibiotics and povidone-iodine on the day of injection, bacterial contamination at the injection site on the bulbar conjunctiva was 43%. That was reduced to 13% after prophylaxis, they said.

The study was published in the June issue of Retina.