Effect of pterygium on corneal astigmatism, irregularity and higher-order aberrations: a comparative study with normal fellow eyes

Abstract

Pterygium is an abnormal growth of fibrous conjunctival tissue that invades the cornea, resulting in corneal distortion, astigmatism, and increased higher-order aberrations (HOAs). However, few studies have compared eyes with pterygium to normal fellow eyes when interpreting HOAs and there is no study that revealed the effect of the thickness or grading of the pterygium on the change of HOAs. Therefore, we evaluated the effects of nasal pterygium by comparing the normal fellow eye of 59 patients. The pterygium significantly increased with-the-rule corneal astigmatism and corneal irregularity. Trefoils, horizontal coma, and quatrefoils were significantly induced by the pterygium. The grading of the pterygium was not correlated with its characteristics except for the thickness. In multiple linear regression analysis, pterygium-induced corneal astigmatic/irregularity values and horizontal trefoil/quatrefoil were associated with the area of the pterygium. The length of the pterygium was an independent inducer of oblique trefoil/quatrefoil, while horizontal coma was independently associated with both its length and width. The thickness was not correlated with any optical parameters. Together, the results demonstrate that nasal pterygium significantly induces corneal astigmatism, irregularity and some HOAs. These pterygium-associated changes in optical parameters could be predicted by the length, width and area of the pterygium.

Influence of Ocular Biometry Parameters on the Predictive Accuracy of IOL Power Formulas in Patients with High Myopia

“…The exclusion criteria of this study included a history of contact lens wearing, corneal abnormalities, pterygium, glaucoma, uveitis, zonular weakness, lens luxation, diabetic retinopathy, invalid ocular biometry, missing postoperative refractive information, and postoperative corrected distance visual acuity (CDVA) less than 20/40. We ruled out patients who had undergone pterygium surgery [ 21 ], corneal refractive surgery [ 22 ], implantable collamer lens (ICL) implantation [ 23 ], or vitrectomy surgery [ 24 ]. These cases were excluded to avoid preexisting surgery-induced changes in ocular anatomical and optical properties.…”

Potential applications of artificial intelligence in image analysis in cornea diseases: a review

“…The prevalence varies but can be as high as 30% depending on population and location [ 40 ]. Whilst generally benign, it has the ability to affect visual acuity through its effect on corneal astigmatism, irregularity and high-order aberrations, or when it covers the visual axis [ 41 ].…”

Resveratrol inhibits TGF-β1–induced fibrotic effects in human pterygium fibroblasts

“…Pterygium is a fibrovascular degenerations of the conjunctiva that extends into the corneal limbus [ 1 ]. It can cause significant damage to visual function, triggering irritation [ 2 ], inflammation [ 3 ] and astigmatism [ 4 ]. Currently, there is no effective drug or conservative treatment for advanced pterygium, and surgery remains the best treatment option.…”