Abstract
Purpose :
To determine limbal vascular changes in patients with limbal stem cell deficiency (LSCD) as measured by anterior segment optical coherence tomography angiography (AS-OCTA).
Methods :
Retrospective review of 20 LSCD patients (20 eyes), classified according to their clinical findings into mild (8 eyes), moderate (7 eyes) and severe (5 eyes), and 10 age- and sex-matched healthy controls (10 eyes) with AS-OCTA. For the limbal vascular analysis, the limbus was defined as the 2mm area posterior to the corneascleral transition that extended to the location of disease in the LSCD group, or the entire limbal area of the scan in the controls. The vessel density (VD), vessel diameter index (VDI) and fractal dimension (FD) were calculated using a validated methodology with ImageJ software. Independent t-tests and ANOVAs were performed to compare these parameters between controls and LSCD patients and between controls and the LSCD stages, accordingly.
Results :
Mean age in the LSCD group and controls were 54.2±19.4 and 41.8±15.1 years, respectively (p= 0.088) with a female prevalence in both groups (62.5% and 55.5%, respectively; p=0.112). Compared to the controls, the limbal vasculature of the LSCD group had an increased VD (43.5±4.9% and 37.3±3.7%, p= 0.002) and FD (1.750±0.041 and 1.710±0.029, p= 0.014). In the LSCD group, the limbal vasculature of the affected area when compared to the area without LSCD, showed increased VD (41.0±4.3% and 37.6±3.1%, p=0.001) and FD (1.730±0.040 and 1.690±0.038, p=0.040). Lastly, there was a significant increase of VD and FD in the moderate and severe LSCD as shown in Figures 1 and 2, but no significant VDI differences between groups.
Conclusions :
AS-OCTA showed a focal increase of the limbal VD and FD that may provide novel, non-invasive and objective parameters for the LSCD assessment, particularly in moderate and severe stages.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.