Is the RPE typically hyper reflective or hypo reflective on OCT?

Is the RPE typically hyper reflective or hypo reflective on OCT?

• A. Hyper reflective
• B. Hypo reflective
• C. Iso reflective
• D. Not visible

Answer: (A)

The RPE appears as a bright, highly reflective band on OCT because its pigmented, densely packed cells and the strong refractive index contrast at the RPE–Bruch’s membrane interface backscatter incident light very effectively. This intense backscatter makes the RPE stand out compared with surrounding retinal layers, so it is seen as a hyperreflective layer with a corresponding signal shadow behind it. If the RPE were hypo reflective, it would imply loss or damage of the RPE; iso reflective would mean it blends with adjacent layers, which is not typical on standard OCT. Not visible would be incorrect since the RPE band is a clearly identifiable feature.

The RPE appears as a bright, highly reflective band on OCT because its pigmented, densely packed cells and the strong refractive index contrast at the RPE–Bruch’s membrane interface backscatter incident light very effectively. This intense backscatter makes the RPE stand out compared with surrounding retinal layers, so it is seen as a hyperreflective layer with a corresponding signal shadow behind it. If the RPE were hypo reflective, it would imply loss or damage of the RPE; iso reflective would mean it blends with adjacent layers, which is not typical on standard OCT. Not visible would be incorrect since the RPE band is a clearly identifiable feature.