Abstract
Purpose :
To investigate the role of high resolution anterior segment optical coherence tomography (HR-ASOCT) in assessing the morphology of pterygia and pingueculae and the relationship to corneal scarring or astigmatism.
Methods :
Single centre cross-sectional case series of patients with nasal primary pterygium and or pingueculae were included. A clinical assessment together with HR-ASOCT based morphometric analysis, color photography and keratometry were undertaken in each patient. Associations were tested between the parameters of the pterygium, degree of corneal scarring, astigmatism and best corrected visual acuity (BCVA).
Results :
29 eyes of 26 patients with pterygium and 6 patients with pinguecula were included. Morphometric analysis of pterygia revealed a mean horizontal corneal length of 2.8±1.3 mm, 0.5±0.2mm limbal thickness, 4.8±1.7mm limbal breadth and affected corneal area of 9.4±6.6 mm2. Loss of integrity of the basement membrane with anterior stromal scarring was found in 23 cases (79.3%) reaching a mean depth of 68.8±21.7 µm (min: 33 µm, max: 126 µm). Depth of anterior stromal scarring had a significant inverse association with BCVA and pterygium thickness (p = 0.011 and p = 0.014). Flat bridging of the corneoscleral transition zone was significantly associated with corneal scarring and the degree of corneal astigmatism, while an inverse association was found for limbal nodularity (Figure 1).
Conclusions :
HR-ASOCT provides useful quantification of the affected corneal area, pterygium thickness and stromal scarring for planning of treatment. Morphology of the corneoscleral transition and epithelial thickness differ between pingueculae, small and advanced pterygia, aiding in the understanding of the pathogenic relationship between pingueculae and pterygia.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.