Retina is our “window to the brain” and can be assessed by numerous non-invasive techniques. Many cerebral vascular and neurodegenerative experts have studied retinal thickness, geometry, vascular supply and so on seeking for the associations and answers related to their fields.
In this study, Li at al studied 154 patients with acute ischemic stroke diagnosed based on TOAST classification. All patients underwent spectral-domain optical coherence tomography (OCT) of the retina for the detection of localized retinal nerve fiber layer defects (RNFLDs) within seven days after the onset of stroke. A RNFLD was defined as a sector on the OCT printout in which the RNFL contour line dipped into the red zone for a length of <180°. The study group was compared with a control group, which was formed from the population of the Beijing Eye Study 2011 with 2890 subjects.
In a first step of the analysis, patients with acute stroke were compared to a control population free of stroke. In a second step, the group of participants of the Beijing Eye Study with previous stroke was compared with the group of participants of the Beijing Eye Study without previous stroke. In a third step of the analysis, the hospital-based group and the Beijing Eye Study with previous stroke group were merged. In a final fourth step of the analysis, the presence of localized RNFLDs was taken as dependent variable. Multiple runs of univariant and multivariant analysis were performed.
This investigation combining a hospital-based study group with a population-based group showed that acute or previous stroke was significantly associated with localized RNFLDs (P<0.001) after adjusting for parameters such as age, gender, arterial hypertension and diabetes mellitus. In a reverse manner, presence of localized RNFL defects was significantly associated with cerebral stroke (P<0.001) in multivariate analysis. Study also established association of localized RNFDLs and arterial hypertension.
Localized RNFLDs can be assessed by noninvasive OCT imaging may be added to the panel of retinal morphological features of stroke. So, relationship is established, now what to do with it?