Abstract
Purpose: :
To evaluate the effect of developing a partial vitreous separation, at the optic nerve, on peripapillary retinal nerve fiber layer thickness (RNFL) as measured by time domain OCT.
Methods: :
The OCT database for patients followed as glaucoma suspects at Montefiore Medical Center was searched for the developement of a partial PVD (pPVD) surrounding the optic nerve. Included subjects had a partial vitreous separation at the optic nerve not seen in previous scans. Twenty-nine patients were identified. Nine of twenty-nine patients were included, based on good quality scans and clearly visible vitreous separation.
Results: :
Average RNFL thickening before partial PVD (no PVD) was 99.00 microns which increased to 104.44 microns (p<0.006) with the development of pPVD. One subject measured the same RNFL thickness while the rest (n=8) had an increase in the RNFL thickness with the development of a pPVD. No subjects demonstrated decreased RNFL thickness with the development of a pPVD.
Conclusions: :
Development of partial vitreous separation increases the thickness of the peripapillary RNFL. Traction to the RNFL by the partially separated vitreous could be an explanation for this observation. Presence of a pPVD should be taken into account when interpreting RNFL thickness at the optic nerve.
Keywords: imaging/image analysis: clinical • optic nerve • vitreous