Intravitreal injection (IVI) therapy, either with anti-vascular endothelial growth factor (VEGF) drugs alone or combined with steroids, was associated with a reduced need for panretinal photocoagulation (PRP) within 2 years, according to new research from Clinical Ophthalmology.
PRP carries a risk of exacerbating preexisting diabetic macular edema (DME). Researchers hoped to determine whether a combination of PRP and injections might reduce laser spots and, consequently, damage to the retina.
Adult patients with diabetes and primary onset proliferative diabetic retinopathy (PDR) (102 eyes) who presented at a German university medical center between 2016 and 2018 were divided into groups based on presence of DME. If eyes did not have DME, they were treated with PRP (group 1). Eyes with DME were treated with PRP and IVI and anti-VEGF agents during the observation period (group 2a). A subgroup of the eyes with DME, group 2b, were treated initially with anti-VEGF agents before changing to steroids treatment.
The researchers classified PDR based on the Early Treatment Diabetic Retinopathy Study Research Group (ETDRS) system and observed the patients from diagnosis of PDR to 24 months.
CMT was higher among the groups 2a and 2b compared with group 1 at baseline (432.1±164.2 μm vs 296.6±69.5 μm P <.01) and at the end of the observation period (382.1±143.8 μm vs 308.9±59.7 μm P =.01). CMT was lower in group 2a at baseline (385.1±128.9 vs 474.8±182.2 P =.01) and last visit 338.8±132.3 vs 425.0±144.0 P <.01) compared with group 2b.
Best-corrected visual acuity (BCVA) was higher among group 2b compared with group 1 at baseline (0.36±0.39 vs 0.27±0.44 P =.01) and at the end of the study period (0.46±0.45 vs 0.28±0.31 P =.01). BCVA was not significantly different in group 2a compared with group 2b at the beginning or end of the study.
At the end of the observation period, applied PRP spots were higher among the group 1 group compared with groups 2a and 2b (2427.4±885.0 vs 1528.8±468.6 P <.01). Quantity of applied PRP spots was not significantly different in both group 2 subgroups (G2a 1428±424.6 vs G2b 1552.8±512 P =.6).
Group 2b underwent 12±4 IVI in the 2 years (8±4 of which with anti-VEGF agents and 4±2 with steroids), compared with 10±4 anti-VEGF agents in group 2a (P =.035). Steroid treatment in group 2b began at 9.9±4.7 months.
“We found that the combined treatment in [group 2] with IVI and PRP therapy has a better outcome on the activity of PDR compared to monotherapy with PRP in terms of a significantly lower number of needed PRP therapy after 24 months,” the researchers report. “Furthermore, switching to steroids in [group 2b] did not lead to a higher number of PRP spots required compared to eyes in [group 2a], which received a sole IVI therapy with anti-VEGF agents alone. This may suggest that IVI therapy with steroids could be a possible alternative to reduce the activity of PDR, too.”
Limitations of the study included its use of decimal visual acuity and a small population from 1 medical center.
Aljundi W, Suffo S, Munteanu C, et al. Intravitreal injection for diabetic macular edemaas adjunctive therapy for proliferative diabetic retinopathy: a retrospective study. Clin Ophthalmol. 2022;16:135-143. doi:10.2147/OPTH.S346065