Retinal perfusion changes in radiation retinopathy

Area of Science:

• Ophthalmology
• Radiation Oncology
• Medical Imaging

Background:

• Radiation therapy is a common treatment for choroidal melanoma.
• Radiation-induced retinopathy can affect visual function.
• Understanding the vascular changes is crucial for patient management.

Purpose of the Study:

• To investigate changes in retinal blood flow and oxygen saturation in patients with retinopathy after plaque radiation therapy for choroidal melanoma.
• To compare vascular parameters between affected and unaffected eyes.

Main Methods:

• Eight patients with unilateral radiation-related retinopathy were studied.
• The fellow eye served as a control.
• Total retinal blood flow (TRBF) and retinal blood oxygen saturation (SaO2, SvO2) were measured using Doppler Spectral Domain Optical Coherence Tomography (OCT) and Hyperspectral Retinal Camera.

Main Results:

• TRBF was significantly lower in the retinopathy eye (33.48 μl/min) compared to the control eye (50.37 μl/min).
• Arteriolar oxygen saturation (SaO2) was higher in the retinopathy eye (101.11%) versus control (94.45%).
• Venular oxygen saturation (SvO2) was also higher in the retinopathy eye (62.96%) versus control (51.24%).

Conclusions:

• Ionizing radiation impacts TRBF, SaO2, and SvO2.
• Clinical presentation resembles rapidly developing diabetic retinopathy.
• Results indicate altered retinal vascular physiology in radiation-related retinopathy.