Frequency of Rhegmatogenous Retinal Detachment after Intravitreal Therapy in Neovascular Age-Related Macular Degeneration
Mammo DA, Ringeisen AL, Parke DW. Frequency of rhegmatogenous retinal detachment after intravitreal therapy in neovascular age-related macular degeneration. Ophthalmology Retina 2020; 4:973-8.
The purpose of this study was to look at patients who developed rhegmatogenous retinal detachment (RRD) within 90 days of intravitreal injection for neovascular AMD (nAMD) and had pars plana vitrectomy (PPV) surgery for repair. The authors looked specifically at quadrant of the retinal break and postoperative injection frequency.
There were 203,000 intravitreal injections for nAMD during the study period of January 1, 2014 through October 30, 2019. A total of 11 different physicians performed injections, all in the superotemporal quadrant using a 30 or 31 gauge needle at a location 3.5 to 4.0 mm from the limbus, depending on the lens status. All physicians used a treat-and-extend protocol, with the goal of resolution of all intraretinal and subretinal fluid. Use of subconjunctival lidocaine and lid speculum varied based on physician discretion.
Seventeen eyes from 17 patients demonstrated RRDs, with a rate of RRD formation of 1:11,941 (0.0084%) within 90 days of intravitreal injection. Patients had an average of 27.56 injections (median 22.5, range 2-97) prior to RRD formation. Of the patients who developed RRD, the superotemporal quadrant was involved most frequently (10 of 16 eyes (62.5%)). All patients had PPV surgery, with the surgical approach varying based on physician discretion. Six patients (35.3%) required a second surgery, many due to proliferative vitreoretinopathy formation. The type of anti-VEGF injected was not associated with increased or decreased time to RRD (p=0.43).
Of patients requiring postoperative injections, the average interval increased from 7.18 weeks to 9.17 weeks after surgery. Eleven of 17 patients (64.7%) either increased their injection intervals or required no further injections, 3 maintained similar intervals, and 3 decreased intervals. Overall, in the 6 months prior to RRD formation, these 17 patients averaged 4.94 +/- 1.89 injections. In the 6 months following RRD formation, these 17 patients averaged 2.76 +/- 2.44 injections, the comparison of which is statistically significant (p=0.009).
The take-away from this paper is that the rate of RRD formation in patients receiving intravitreal injections is low. Additionally, single-surgery success rate may be lower than in comparison to noninjection patients, and injection intervals may lengthen after PPV in nAMD patients.