Abstract
Purpose: :
We hypothesize that retinal damage from cotton wool spots (CWS) is permanent and can be evaluated if the resolved inner retinal gliosis can be imaged accurately. The purpose is to visualize CWS and characterize the optical density change of the inner retina (hyper–reflective sign) after ophthalmoscopic resolution of CWS with a new device combining real time OCT and SLO fundus imaging (OTI Inc., Toronto, Canada) that allows simultaneous retinal imaging and high–resolution OCT B and C (coronal) scans.
Methods: :
Non–interventional, consecutive case series. The group included 13 eyes of 11 patients (5 men, 6 women) presenting with CWS due to diabetes (n=5), human immunodeficiency virus (HIV) (n=3), branch retinal vein occlusion (BRVO) (n=3) and hypertension (n=2). Eight eyes had acute CWS visible on fundus photographs and 5 eyes had resolved CWS. The fundus photography served as a template for localization of OCT scanning in acute and resolved CWS using both types of imaging.
Results: :
We were able to image both active and resolved CWS and show that the presumed glial scar after resolved CWS is permanent and visible as a hyper–reflective inner retinal scar. These images confirmed the changes we had previously observed with StratusOCT instrument. The combined instrument has a wide angle of view and makes imaging and localizing lesions external to the major vascular arcades easy. Real time images of OCT and SLO were acquired simultaneously making precise localization possible. The combined instrument acquires adjoining B scans without the necessity of patient realignment or re–orientation of the scan after a single capture. The combined instrument also allows scanning in coronal en face plane which enables three dimensional reconstruction of the image. Overlaying SLO and OCT images with the combined instrument creates a high precision image of co–localization of intraretinal lesions.
Conclusions: :
Using the new combined SLO/OCT instrument shows that retinal cotton wool spots leave permanent hyper–reflective scars which may be used to quantify retinal damage. The use of the combined SLO/OCT may be advantageous in definitive localization of lesions using either the serial B scan mode or C scan mode and in mapping total retinal damage in patients who sustain multiple retinal microinfarctions.
Keywords: imaging/image analysis: clinical • retina