Longitudinal changes in vessel density and retinal nerve fiber layer thickness after acute primary angle closure

Area of Science:

• Ophthalmology
• Glaucoma Research
• Vascular Imaging

Background:

• Acute primary angle closure (APAC) is a serious ophthalmic condition.
• Understanding the long-term effects of APAC on optic nerve vasculature is crucial for managing glaucoma progression.
• Peripapillary optic disc vessel index changes after APAC require further investigation.

Purpose of the Study:

• To evaluate initial and longitudinal changes in peripapillary optic disc vessel index in eyes with a history of APAC.
• To determine if circumpapillary vessel density (cpVD) or retinal nerve fiber layer (RNFL) thickness is a better predictor of glaucoma progression after APAC.

Main Methods:

• A study included 21 Chinese patients treated for unilateral APAC.
• APAC eyes and contralateral control eyes were monitored post-treatment (surgery for APAC eyes, laser peripheral iridotomy for control eyes).
• Ophthalmic examinations including cpVD and RNFL thickness using SS-OCT were performed at multiple follow-up points up to 1 year.

Main Results:

• APAC eyes showed significantly reduced cpVD 1 day after the episode and 1 week post-surgery compared to unaffected eyes.
• cpVD remained stable during the 1-year follow-up.
• RNFL thickness initially thickened then progressively thinned, stabilizing at 6 months.
• Peripapillary VD correlated positively with RNFL thickness and negatively with VF mean deviation.

Conclusions:

• Circumpapillary VD significantly decreases in APAC eyes post-resolution and remains stable.
• RNFL thickness stabilizes later at 6 months.
• cpVD appears to be a more sensitive predictor of glaucomatous progression in APAC patients than RNFL thickness.