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Published on: August 11, 2023
Cotton Wool Spots after Anti-Vascular Endothelial Growth Factor Therapy for Macular Edema Associated with Central
Teruyo Kida1, Akitaka Tsujikawa, Yuki Muraoka
1Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan.
Purpose:
To report a case series, whereby we encountered a transient increase in retinal cotton wool spots (CWS) following anti-vascular endothelial growth factor (anti-VEGF) therapy for the treatment of macular edema secondary to central retinal vein occlusion (CRVO).
Methods:
Eighteen eyes were treated with intravitreal aflibercept (IVA), and 5 were treated with intravitreal ranibizumab (IVR). Fundus photographs obtained 1 month after initial IVA or IVR injections were retrospectively evaluated for the presence of CWS.
Results:
Twenty-one (91.3%) patients had the following systemic diseases: hypertension, diabetes mellitus without retinopathy, dyslipidemia, or chronic renal failure requiring dialysis. One month after treatment, reduced macular edema was observed in 21 (91.3%) eyes. Initial injections facilitated complete resolution in 14 eyes, and CWS gradually became fainter with additional injections.
Conclusion:
Some eyes with CRVO-related macular edema can show a transient increase in CWS after initial anti-VEGF therapy; however, macular edema, retinal hemorrhage, and visual acuity were improved in almost every case.

