Abstract
Purpose:
Hard exudates (HE) represent lipid-rich extravascular deposits in the retina that are frequently seen with diabetic macular edema (DME). The presence and growth of HE, particularly near the fovea, is thought to be associated with an increased risk of visual impairment. We analyzed the effect of anti-VEGF therapy with ranibizumab on HE lesions in participants from the RIDE and RISE Phase III trials.
Methods:
A total of 759 patients with DME were randomized 1:1:1 to receive monthly 0.3 mg or 0.5 mg ranibizumab, or sham injections. Fundus photographs were graded by a central reading center. The total area of HE in the central, inner and outer subfields of the study eye was categorized as absent (absent or questionable) and present (definite, obvious, moderate or severe). Non-gradable photographs were excluded as missing. Change in total area of HE from baseline was calculated in mm2.
Results:
Data from 739 patients were available for analysis. Through 24 months of treatment the percentages of study eyes in the absent category increased from 20.9% to 36.5% in the sham arm and from 22.1% to 60.7% and 23.6% to 61.2% in the ranibizumab 0.3 and 0.5 mg arms respectively. The resolution of DME was not paralleled by an increase in HE. Decrease in percentage of study eyes in the HE present category was evident after 6 months in the ranibizumab arms. At baseline, there was no correlation between VA and presence of HE in the central subfield in any treatment arm. Post-baseline, there was no consistent correlation between presence of HE in the central subfield and VA change over time.
Conclusions:
In this exploratory analysis, ranibizumab appears to result in a reduction in the distribution of HE in patients with DME. However, baseline VA was not associated with the presence of HE, nor was the therapeutic benefit of ranibizumab on visual acuity clearly associated with the presence or absence of HE in the central subfield. Additionally, contrary to prior expectations, the presence and area of HE did not increase as DME resolved (both in the ranibizumab or sham groups).
Keywords: 499 diabetic retinopathy •
505 edema •
688 retina