Session Title: Free Paper Session 11: Vascular Diseases & Diabetic Retinopathy III
Session Date/Time: Friday 08/09/2017 | 11:00-12:30
Paper Time: 11:06
Venue: Room 114
First Author: : B.Clarke UK
Co Author(s): : D. Inzerillo B. Gupta
To our knowledge, there are no major reports on incidence of endophthalmitis following dexamethasone implant without co-injection of anti-vascular endothelial growth factor agents (anti-VEGF.) We report the first clinical data on incidence of endophthalmitis after 815 dexamethasone-only procedures in a tertiary referral eye unit based in the United Kingdom. We discuss risk factors and outcomes for the cases involved.
Southampton University Hospital Eye Unit is a tertiary referral centre on the south coast of England. It runs a specialised intravitreal injection unit for medical retina patients, as well as ophthalmic operating theatres with access to vitreoretinal services. Data from both settings were reviewed.
This was a retrospective study of all patients between 1st March 2010 and 1st March 2017. Data were collected from the electronic patient record system to find all cases of postoperative endophthalmitis. Patient records were evaluated to determine causative surgery and identify dexamethasone implant-related cases. This was compared to total numbers of dexamethasone implant injections performed to determine incidence rate. Cases were also analysed to determine pre-existing risk factors, management of infection, and final visual outcome.
We found documentation for 815 intravitreal dexamethasone implants over the period studied. There were a total of three cases treated for endophthalmitis, giving an incidence rate of 0.37%. One of these cases was in a vitrectomised eye with postoperative wound leak and hypotony requiring surgical exploration and suturing of the injection site. All patients had reduced acuity post infection, but retained enough vision to be considered for subsequent anti-VEGF injections.
Our rate of 0.37% was higher than recent data from the USA reporting on mixed dexamethasone with or without anti-VEGF co-injections (0.06-0.13%). By comparison, anti-VEGF injections alone have been reported to carry in infection rate of 0.053%. The main risk factor identified in our group was previous vitrectomy with post injection wound leak in one of the three cases. If this case were to be excluded, the incidence rate falls to 0.25%, which would be more closely in line with the previous data. With such small numbers of endophthalmitis, post vitrectomy status requires further study as a risk factor for possible increased rate of infection. In the meantime, this case has changed our local injection protocol: Any vitrectomised eye requiring dexamethasone implant undergoes injection in ophthalmic operating theatres, and the intraocular pressure is checked before being discharged, with a view to wound suturing if hypotony occurs. Eyes requiring dexamethasone implant are at a higher risk of complications and these findings are crucially important for informed consent. Analysis of the cases involved has guided review of our local injection policies, and may be worth considering by other health providers as indications and volume of intravitreal steroid injection continue to expand.