Herman Christiaan Izaak Themen , Dennis Ricardo August Mans , Robert Bipat , Denise Judith Doelwijt , Dineshpersad Jiawan , Annemarie Thelma Bueno de Mesquita-Voigt
Background: Loss of elastic properties, the introduction of tractional forces, and shortening of the plica-limbal distance (the distance between the nasal limbus and the semilunar plica bottom in full abduction) are common anatomical abnormalities in eyes of patients with primary medial pterygium. In this study, we assessed whether, and to which degree the latter phenomenon correlated with the presence of pterygium.
Methods and findings: Plica-limbal distance was measured using a slit lamp in individuals who came for routine eye examination, and was related to pterygium size, as well as to patients’ gender and age. Data were expressed as means (95% CI). Eighty-three males and 118 females were enrolled in the study. There were 49 eyes from patients with unilateral pterygium, 84 from patients with bilateral pterygium, and 220 from individuals who did not suffer from either uni- or bilateral pterygium. The mean plica-limbal distance in eyes with pterygium (7.3 mm, 95% CI: 6.9 – 7.7 mm) was significantly shorter than that in eyes without pterygium (9.9 mm, 95% CI: 9.7 – 10.1 mm). Plica-limbal distance correlated inversely with pterygium size (r2 = 0.32, p < 0.0001), was not related to gender, but decreased with increasing age in both individuals with and without pterygium.
Conclusion: Our results suggest that plica-limbal distance correlated inversely with the presence of pterygium. This finding may have important consequences for the identification of individuals at risk, as well as for improvement of the treatment of this condition.
