Glaucoma drainage devices: risk of exposure and infection

To identify risk factors for device exposure and intraocular infection following implantation of a glaucoma drainage device.

Retrospective case series.

The medical records of adult patients undergoing glaucoma drainage device implantation at an academic medical center between 2000 and 2010 were reviewed. Main outcome measures included device exposure and intraocular infection.

Seven hundred and sixty-three cases were identified. These included 702 primary implants (ie, the first drainage device implanted into an eye) and 61 sequential implants. Among 702 primary implants, there were 41 cases of exposure (5.8%). None of the potential risk factors were statistically significant. Implant location was found to be a marginally significant risk factor. The exposure rates for inferior and superior implants were 12.8% (5 of 39) and 5.4% (36 of 663), respectively (P = .056). The highest rate of exposure for primary implants occurred in the inferior-nasal quadrant (17.2%, 5 of 29). The rate of exposure for sequential devices was 13.1% (8 of 61), with the highest rate also found in the inferior-nasal quadrant (20%, 5 of 25). Of 49 total exposures, 8 were associated with intraocular infection (16.3%). Exposures over inferior implants were more likely to be associated with infection than exposures over superior implants (41.7% vs 8.1%; P = .0151).

Implant location approached, but did not reach, statistical significance as a risk factor for exposure. Exposures over inferior implants place patients at a higher risk of infection than superior exposures. More studies are needed to identify modifiable risk factors for device exposure.