Avisar R, Loya N, Yassur Y, Weinberger D
Department of Ophthalmology, Rabin Medical Center, Petah Tiqva, Israel.
Isr Med Assoc J. 2000 Jan;2(1):14-5.
Previous work has suggested an association between increasing size of pterygium and increasing degrees of induced corneal astigmatism.
To assess the quantitative relation between pterygium size and induced corneal astigmatism using a computerized corneal analysis system (TMS II) and slit-lamp beam evaluation of pterygium size, and to conclude whether corneal astigmatism is an early indication for surgical intervention.
We evaluated 94 eyes of 94 patients with unilateral primary pterygium of different sizes, using TMS II and slit-lamp beam measurements of the size of the pterygium (in millimeters) from the limbus to assess parameters of pterygium size with induced corneal astigmatism. Best corrected visual Snellen acuity was performed.
Primary pterygium induced with-the-rule astigmatism. Pterygium extending > 16% of the corneal radius or 1.1 mm or less from the limbus produced increasing degrees of induced astigmatism of more than 1.0 diopter. Significant astigmatism was found in 16.16% of 24 eyes with pterygium of 0.2 up to 1.0 mm in size, in 45.45% of 22 eyes with pterygium of 1.1 up to 3.0 mm in size (P < or = 0.0004), and in 100% of 3 eyes with pterygium of 5.1 up to 6.7 mm in size (P = 0.0005). We found that visual acuity was decreased when topographic astigmatism was increased.
When primary pterygium reaches more than 1.0 mm in size from the limbus it induces with-the-rule significant astigmatism (> or = 1.0 diopter). This significant astigmatism tends to increase with the increasing size of the lesion. Topographic astigmatism tends to be improved by successful removal of the pterygium. These findings suggest that early surgical intervention in the pterygium may be indicated when the lesion is more than 1.0 mm in size from the limbus.
以往的研究表明翼状胬肉大小增加与诱导性角膜散光程度增加之间存在关联。
使用计算机化角膜分析系统（TMS II）和裂隙灯光束评估翼状胬肉大小，评估翼状胬肉大小与诱导性角膜散光之间的定量关系，并得出角膜散光是否是手术干预的早期指征。
我们使用TMS II和裂隙灯光束测量从角膜缘起翼状胬肉的大小（以毫米为单位），评估94例单侧原发性不同大小翼状胬肉患者的94只眼，以评估翼状胬肉大小与诱导性角膜散光的参数。进行最佳矫正视力的Snellen视力检查。
原发性翼状胬肉导致顺规散光。翼状胬肉从角膜缘延伸超过角膜半径的16%或1.1毫米及以下时，诱导性散光度数增加超过1.0屈光度。在24只大小为0.2至1.0毫米的翼状胬肉眼中，16.16%出现显著散光；在22只大小为1.1至3.0毫米的翼状胬肉眼中，45.45%出现显著散光（P≤0.0004）；在3只大小为5.1至6.7毫米的翼状胬肉眼中，100%出现显著散光（P = 0.0005）。我们发现当地形图散光增加时，视力会下降。
当原发性翼状胬肉从角膜缘起大小超过1.0毫米时，会导致顺规显著散光（≥1.0屈光度）。这种显著散光往往随着病变大小的增加而增加。成功切除翼状胬肉后，地形图散光往往会改善。这些发现表明，当病变从角膜缘起大小超过1.0毫米时，可能需要对翼状胬肉进行早期手术干预。
