Prospective evaluation of the incidence and risk factors for the development of RPE tears after high- and low-dose ranibizumab therapy

Abstract

Purpose: To prospectively determine the incidence and risk factors for retinal pigment epithelial (RPE) tears in eyes with vascularized pigment epithelial detachments (PED) and exudative age-related macular degeneration receiving antivascular endothelial growth factor therapy.

Methods: Eyes were prospectively randomized into 1 of 4 arms: 1) 0.5 mg of ranibizumab monthly for 12 months; 2) 0.5 mg of ranibizumab monthly for 3 months and then pro re nata on the basis of clinical and optical coherence tomography-guided indications; 3) high-dose 2.0 mg of ranibizumab monthly for 12 months; or 4) 2.0 mg of ranibizumab monthly for 3 months and then pro re nata thereafter. All PEDs were measured for height, greatest linear diameter, and surface area at baseline. The incidence of RPE tears in the entire 4-arm cohort was determined at the end of 12 months. Eyes were divided into two groups (tear vs. nontear) and statistically compared to determine risk factors for the development of RPE tear.

Results: Of 37 eyes, a total of 5 developed postranibizumab RPE tears during the course of the study (incidence 14%). Four of the 5 tears occurred in the high-dose 2.0-mg groups. Baseline PED height, surface area, and greatest linear diameter were significantly greater in the group that developed RPE tears versus the nontear group (P = 0.018, 0.031, and 0.048, respectively). There were significantly more eyes with PED height >550 microns in the RPE tear group (4 of 5, 80%) compared with the nontear group (9 of 32, 18%) (P = 0.042). The presence of PED height >550 microns was associated with an increased tear rate from 14% to 31%. Furthermore, retrospective identification of a ring sign or Grade 1 tear at baseline, in addition to PED height >550 microns, was associated with a further increase in the tear rate to 67%.

Conclusion: In this study, the prospective incidence of RPE tears was ∼14%. A baseline PED height >550 microns and presence of a Grade 1 tear, or positive ring sign, were identified as high-risk factors for the subsequent development of an RPE tear.