Transient Retinal Vessel Whitening After Whole-Ventricle Radiotherapy.

We report a case of transient peripheral retinal vessel whitening following whole-ventricle radiotherapy in a pediatric patient, which resolved spontaneously without signs of ischemia. An 11-year-old girl with a pituitary germinoma underwent chemotherapy and whole-ventricle radiotherapy (23.4 Gy in 13 fractions). At two months post-treatment, ultra-widefield scanning laser ophthalmoscopy revealed bilateral peripheral retinal vessel whitening, raising suspicion of nonperfusion areas. However, optical coherence tomography angiography (OCTA) confirmed preserved retinal blood flow without ischemia. Visual field testing did not reveal any abnormalities. No intervention was performed, and the whitening resolved spontaneously within two months. Unlike typical radiation retinopathy, this represents a reversible, non-ischemic process, which could be attributed to the limited radiation exposure received during whole-ventricle radiotherapy and vascular plasticity in young patients. Given that radiation retinopathy is generally considered uncommon below 45 Gy, this case presents a characteristic retinal vascular change occurring at lower radiation doses and underscores the importance of retinal evaluation even in low-dose irradiation settings. Non-invasive imaging techniques, such as OCTA and ultra-widefield scanning laser ophthalmoscopy, can be valuable for monitoring subtle radiation-induced retinal changes. Further research is needed to refine screening and management strategies for radiation-induced retinal effects.