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Purpose: To establish determining factors for fast corneal sensitivity (CS) recovery after pterygium excision.Methods: Thirty-two eyes of 14 males and 18 females with primary nasal pterygium were recruited. Differences in CS (in the four quadrants and the center using Cochet-Bonnet esthesiometer), pterygium corneal area (PCA), tear osmolarity, tear break up time, Schirmer test, and ocular symptoms were analyzed before and 1 month after lesion excision. The relationship between CS recovery (difference between the two time points; CS1-CS0) and the other features was assessed.Results: All the studied locations exhibited normal (6 cm) or near normal mean CS at the 2 time points, except tendency for moderate hypoesthesia in nasal CS0 (median 4.5; range: 1.5 -6.0 cm). Point by point comparison revealed significant postoperative improve in nasal location (p=0.008; Wilcoxon rang test) with normal values in 17 eyes (53%) and a median CS1= 5.0 cm (2.5 -5.5 cm) in 15 eyes with no complete recovery. No significant correlation was found between CS0 and the studied variables and CS1 was only significantly correlated with PCA (rho: -0.441; p<0.05). CS recovery also showed significant correlation with PCA (rho= -0.516; p<0.01). Conclusions:Corneal sensitivity recovery after pterygium excision showed important variability and the only studied factor that seems to be determinant could be PCA. It would be advisable to operate while lesion is relatively small, with lower surgical injury, and faster and complete recovery, thus protecting ocular surface homeostasis.3

Considering the results from the three meridians under investigation, it may be concluded that keratoconus onset has an impact on the anterior segment as a whole and not only on corneal structures. The DL distance is a useful parameter to describe limbal changes in keratoconus.

Objectives: To describe and compare corneal peripheral angles in normal and keratoconic eyes, to gain a better understanding of the topography of the periphery of the cornea in keratoconus and assist practitioners in the selection and fitting of large diameter contact lenses. Methods: Eighty-eight eyes were included in the study, divided in three groups: healthy (A0, 28 eyes), keratoconus at stage I according to the Amsler-Krumeich classification (AI, 33 eyes) and keratoconus at stages II to IV (AII, 27 eyes). The Pentacam Scheimpflug system was employed to manually measure the corneal peripheral angles corresponding to a chord length range between 8.6 and 12.6 mm at eight different peripheral locations. Results: The peripheral angle was influenced by ocular condition and by the peripheral location, with no interaction effect between both factors. Statistically significant differences were found in mean corneal peripheral angles between group A0 (30.84º±2.33º) and AI (31.63º±2.02) (p=0.001) and between A0 and AII (31.37º±2.11º) (p=0.030). The differences between AI and AII were not significant. In all eyes, the largest and smallest peripheral angles were found at the temporal inferior and temporal superior locations, respectively, with a mean difference between largest and smallest of 3.37 ±1.42º in healthy eyes and 2.96 ±1.54º in keratoconus (AI + AII). Conclusion: Clinically insignificant differences were found in peripheral angles between keratoconus and healthy eyes, giving support to the use of large diameter, intralimbal contact lenses with peripheral designs, and resting on the same corneal region, as those fitted on normal corneas.

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