Fluorescence lifetime imaging in retinal artery occlusion

Area of Science:

• Ophthalmology
• Medical Imaging
• Biophotonics

Background:

• Endogenous retinal fluorophores exhibit characteristic decay times.
• Fluorescence lifetime imaging ophthalmoscopy (FLIO) measures these decay times.
• Retinal artery occlusion (RAO) affects blood supply to the retina.

Purpose of the Study:

• To investigate changes in retinal fluorescence lifetimes in patients with central and branch retinal artery occlusion.
• To assess the utility of FLIO in diagnosing acute ischemic retinal damage.

Main Methods:

• FLIO was performed on 24 patients with RAO, using the contralateral unaffected eye as a control.
• Measurements were taken using a HRA Spectralis system with 473 nm excitation.
• Mean fluorescence lifetimes were analyzed in short (498-560 nm) and long (560-720 nm) spectral channels.

Main Results:

• Retinal fluorescence lifetimes were significantly prolonged in ischemic areas within 3 days of RAO compared to controls.
• A 50% increase was observed in the short spectral channel and a 20% increase in the long spectral channel.
• No significant difference in lifetimes was found between affected and unaffected eyes in the post-acute stage.

Conclusions:

• RAO causes prolonged retinal fluorescence lifetimes during the acute phase.
• FLIO shows potential as a valuable indicator for acute ischemic retinal damage.
• This technique may aid in the early detection and diagnosis of RAO.