Comparison of Vascular Outgrowth Rate and Retinal Vascular Development Border after Intravitreal Injection of Aflibercept or Bevacizumab to Treat Retinopathy of Prematurity

Quantitative vascular outgrowth and anatomic and refractive outcomes of eyes treated with bevacizumab in posterior zone Ⅰ

PURPOSE

To report the anatomic and refractive outcomes and retinal vascular outgrowth in eyes with posterior zone Ⅰ retinopathy of prematurity (ROP) treated with intravitreal bevacizumab (IVB).

METHODS

Thirty-eight eyes of 21 infants treated with IVB for type 1 and aggressive-ROP, and whose posterior border of retinal vascularization was shorter than the optic disc-to-fovea distance were defined as posterior zone Ⅰ and included in the study.

RESULTS

Nine eyes of five infants whose follow-up time was lower than four months were accepted as insufficient for clinical outcomes. Additional treatment(s) had been performed up to 60 weeks postmenstrual age (PMA) in 10 of 29 eyes whose follow-up were higher than four months. Macula was attached at the final examination in all eyes with > 4 months follow-up. Anatomical outcome of two eyes of one infant was accepted as unfavorable whose routine follow-up was interrupted after successful initial treatment and who was presented with straightening of the temporal vascular arcade and residual fibrovascular tractional bands on the temporal periphery. The mean progression of temporal retinal vascularization was 3.6 ± 2.0 horizontal disc diameters (DD) within 7.3 weeks and 5.1 ± 2.5 horizontal DD within 69.1 weeks in the short-term (n=15) and long-term evaluated eyes (n=21), respectively. The mean spherical equivalent was -4.1 diopters at a mean age of 21 months (n=28).

CONCLUSIONS

A favorable outcome had been achieved in almost all bevacizumab-treated eyes, but additional treatments were required. Significant progression of retinal vascularization was detected even in the eyes with short follow-up.

Inter-eye comparison of retinal vascular growth rate and angiographic findings following unilateral bevacizumab treatment

PURPOSE

To compare retinal vascularization progression rate, final retinal vascularization, and fluorescein angiography (FA) findings in infants who received intravitreal bevacizumab (IVB) treatment in one eye and with spontaneous regression in the other eye.

METHODS

Thirty eyes of 15 infants who underwent IVB in one eye due to asymmetric retinopathy of prematurity, and who had pre-treatment fundus photographs and fluorescein angiography images were included in the study. Horizontal disc diameter (DD), optic disc-to-fovea distance (FD), and the length of temporal retinal vascularization (LTRV) distance were measured by evaluating pre-treatment and FA images.

RESULTS

The mean ages at the time of treatment and FA were 40.38  ±  3.35 and 68.72  ±  10.52 weeks postmenstrual age, respectively. The pre-treatment LTRV/FD ratio was 3.11  ±  0.41 in the treated eyes and 3.26  ±  0.43 in the non-treated eyes (p  =  0.053). The final LTRV/FD ratio was 4.23  ±  0.38 in the treated group and 4.33  ±  0.37 in the non-treated group (p  =  0.286). Staining of the vessels, hyperfluorescent focus, and irregular branching of the vessels were similar between the groups, respectively (p  =  1.000; p  =  0.250; p  =  0.625).

CONCLUSION

The progression rate of retinal vascularization and angiographic findings were similar between the treated eyes and the non-treated eyes. Our study suggests that incomplete retinal vascularization in eyes treated with anti-vascular endothelial growth factor (VEGF) is due to the nature of the disease, and anti-VEGF treatment was not to cause cessation in vascular progression.

Comparison of aflibercept and bevacizumab in the treatment of type 1 retinopathy of prematurity

Background

To evaluate the outcome of intravitreal bevacizumab (IVB) and aflibercept (IVA) injection for patients with retinopathy of prematurity (ROP).

Methods

In this single-center retrospective cohort, the recorded medical data of the infants who had been undergone intravitreal injection with either bevacizumab or aflibercept for type 1 ROP were reviewed. The infants were allocated into two groups. IVB group included patients who were treated with bevacizumab as initial treatment and the IVA group included patients who were treated with aflibercept as initial treatment. The rate and time of complete regression, as well as the recurrence rates, were compared between the groups.

Results

A total of 889 eyes of 453 infants were enrolled in the study. There were 865 eyes of 441 infants in the IVB group and 24 eyes of 12 infants in the IVA group. Follow-up time was 289 ± 257 days in the IVB group and 143 ± 25 days in the IVA group (p < 0.001). The difference in the ROP zone was not statistically significant between the 2 treatment groups (p = 0.328). All eyes in the IVA group showed initial regression of ROP after the intravitreal injections. These regressions were achieved in 830 (96.0%) eyes that were injected with IVB (p = 0.023). The median observed regression time was 10 days and 16 days in eyes treated with bevacizumab and aflibercept respectively. Recurrence was noted in 3.9% of eyes (34/865) in the IVB group and 58.3% of eyes (14/24) in the IVA group (p < 0.001).

Conclusion

While the regression rate in the IVA group was significantly higher than in the IVB group, the recurrence rate was significantly more in the IVA group, which may be attributed to differences in the pharmacokinetics of these drugs in the vitreous body.