Purpose: The aim of our study was to assess the visual quality of pterygium patients with total ocular aberrations, and not only corneal aberrations. Methods: 46 eyes of 37 pterygium patients (mean age 48 ± 15 years) were evaluated in a retrospective study. Inclusion criteria were primary pterygium, without any previous surgical treatment. Before surgery, subjective refraction, corrected distance visual acuity (CDVA), with an EDTRS optotype chart, and Zernike coefficients for a 5 millimetres (mm) pupil diameter measured with an Alcon LadarWave total aberrometer (Fort Worth, Texas, USA) were determined. Pterygium size in mm was measured by an experienced ophthalmologist using a slit beam of light from the limbus to the limit of the pterygium. Statistical analysis was performed using SPSS software version 26.0. The Kruskal‐Wallis test with the Tukey–Kramer criterion was used to examine the influence of the extent of corneal invasion on manifest refraction and Zernike coefficients. One‐way analysis of variance (ANOVA) with the Bonferroni criterion was performed to compare different extent values. A p value less than or equal to 0.05 was considered statistically significant. Results: The sample was divided in four groups, according to the extent of corneal invasion. The upper limits of each category were 1, 2, 3 and 4 mm, with 9, 20, 11 and 6 patients in each group, respectively. Preoperatively spheres more positive were found at high corneal invasion groups, statistically significant between 1 and 3 mm, and between 2 and 3 mm (p = 0.013 and p = 0.011) and cylinder axes were between 20° and 50° in all groups. CDVA was lower in patients with greater corneal invasion. Regarding total ocular aberrations, statistically significant differences between groups were found only in a reduced set of Zernike polynomials but oblique astigmatism (2,‐2) appeared in most of the comparatives. Most of the Zernike coefficients, were out of normal limits, compared to control values, including spherical aberration. Conclusions: Pterygium‐induced aberrations also modify the visual quality of patients when the effect of the crystalline lens aberrations is considered, the conclusions are similar to those derived from corneal aberrations. CDVA was lower preoperatively in patients with greater corneal invasion (4 mm).

Purpose: to assess anterior scleral thickness (AST) across diverse scleral meridians and to evaluate the relationship with corneal biomechanical response and several ocular parameters. Methods: This prospective non‐randomized study comprised 50 eyes of 50 patients (mean age, 29.02 ± 9.48 years). Anterior scleral thickness was measured meridionally at three scleral locations (1‐, 2‐, and 3‐mm posterior to the scleral spur) using swept‐source optical coherence tomography. A multivariate model was created to associate AST with several ocular parameters. Principal component analysis (PCA) was used to reduce linearly the dimensionality of seven biomechanical input metrics to two significant components, C1 and C2. Two multivariate analyses were performed to associate C1 and C2 with AST and ocular parameters. Results: AST was thickest in the inferior (581 ± 52 μm) and thinnest in the superior meridian (441 ± 42 μm) when compared to all meridians (p < 0.001), and similar in the nasal (529 ± 53 μm) and temporal (511 ± 59 μm) meridians (p > 0.05). The sclera exhibited the thinnest point 2 mm posterior to the scleral spur (p < 0.001). The AST was significantly linked with axial length, central corneal thickness, and intraocular pressure (p < 0.001). The PCA showed that C1 accounts for 53.84% whereas C2 for the 16.51% of the total variance in the original variables. The C1 model was significantly associated with AST along all meridians (p < 0.001). The partial correlation was moderate in the nasal (r = −0.36, p < 0.001) and inferior (r = −0.26, p = 0.004) meridians whereas weak in the temporal (r = −0.14, p = 0.05) and superior (r = −0.15, p = 0.05) meridians. Conclusions: The relationship between the new biomechanical component and the AST provides the first evidence of the association of AST with the corneal response parameters which should be considered in corneal response interpretation. Tissue thickness varied significantly among meridians supporting the asymmetrical expansion of the ocular globe. The AST was associated with several ocular parameters.

No abstract

No abstract