Abstract
Purpose :
Anti-vascular endothelial growth factor (VEGF) agents are now considered to be the first line therapy for patients with visual loss due to foveal involving diabetic macular edema (DME). However, in many patients, the response is sub-optimal, and about 25%, there is no anatomical response in the first 6 months. As we now have other options, such as steroids and surgery, it might be useful to predict those with poor anatomical response and consider steroids or surgery as first line therapy.
Methods :
A total of 152 consecutive foveal involving DME patients, who have received ranibizumab 0.5 mg (an anti-VEGF agent) monthly for 6 months were included in the study. All patients had spectral-domain optical coherent topography (SD-OCT) using Heidelberg Spectralis (Heidelberg, Germany) at baseline and at 6 months (1 month after the last injection). We divided the patients into 3 groups based on the reduction of central sub-field thickness (CST), namely non-responder NR (<10% reduction), partial-responder PR (>10% reduction but not normal), and good responder GR (normal central thickness). The baseline SD-OCT were scored based on the presence or absence of the following features, subretinal fluid, petalloid appearances, foveal eversion, foval edema, epiretinal membrane (ERM) and central foveal cyst. Only the NR and the GR groups were used for statistical analysis using Chi-Square test.
Results :
There were 47 (31%) patients in the NR group (average age 68, 52% female), 35 (23%) in the PR group (average age 67, 30% female), and 70 (46%) in the GR group (average age 67, 40% female). There were no statistical significant difference in all the analysed features except the presence of ERM (51.1% in NR vs 27.1% in GR group, p=0.008). The presence of subretinal fluid was less common in the NR group but did not reach statistical significant (10.6% in NR vs 20.0 % in GR group, p=0.10).
Conclusions :
The presence of ERM statistically increases the risk of non-anatomical responding in SD-OCT with 6 ranibizimab injections in DME patients. It is unclear whether the thickness or the location of the ERM would increase the prediction value. Furthermore, it is unclear whether steroids would be useful in this group of patients. Surgical intervention might be needed in some cases.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.