Minami Keiichiro, Miyata Kazunori, Otani Atsushi, Tokunaga Tadatoshi, Tokuda Shouta, Amano Shiro
Miyata Eye Hospital, 6-3 Kurahara-cho, Miyakonojo, Miyazaki, 885-0051, Japan.
Kagoshima Miyata Eye Clinic, Kagoshima, Japan.
Jpn J Ophthalmol. 2018 May;62(3):342-348. doi: 10.1007/s10384-018-0583-8. Epub 2018 Mar 12.
To determine steep increase of corneal irregularity induced by advancement of pterygium.
A total of 456 eyes from 456 consecutive patients with primary pterygia were examined for corneal topography and advancement of pterygium with respect to the corneal diameter. Corneal irregularity induced by the pterygium advancement was evaluated by Fourier harmonic analyses of the topographic data that were modified for a series of analysis diameters from 1 mm to 6 mm. Incidences of steep increases in the asymmetry or higher-order irregularity components (inflection points) were determined by using segmented regression analysis for each analysis diameter.
The pterygium advancement ranged from 2% to 57%, with a mean of 22.0%. Both components showed steep increases from the inflection points. The inflection points in the higher-order irregularity component altered with the analysis diameter (14.0%-30.6%), while there was no alternation in the asymmetry components (35.5%-36.8%). For the former component, the values at the inflection points were obtained in a range of 0.16 to 0.25 D.
The Fourier harmonic analyses for a series of analysis diameters revealed that the higher-order irregularity component increased with the pterygium advancement. The analysis results confirmed the precedence of corneal irregularity due to pterygium advancement.
确定翼状胬肉进展引起的角膜不规则度急剧增加。
对456例连续的原发性翼状胬肉患者的456只眼进行角膜地形图检查，并测量翼状胬肉相对于角膜直径的进展情况。通过对1毫米至6毫米一系列分析直径的地形图数据进行傅里叶谐波分析，评估翼状胬肉进展引起的角膜不规则度。使用分段回归分析确定每个分析直径下不对称性或高阶不规则度成分（拐点）急剧增加的发生率。
翼状胬肉进展范围为2%至57%，平均为22.0%。两个成分从拐点处均显示出急剧增加。高阶不规则度成分的拐点随分析直径而变化（14.0% - 30.6%），而不对称性成分则无变化（35.5% - 36.8%）。对于前一个成分，拐点处的值在0.16至0.25 D范围内获得。
对一系列分析直径进行的傅里叶谐波分析表明，高阶不规则度成分随翼状胬肉进展而增加。分析结果证实了翼状胬肉进展导致角膜不规则度增加的先后顺序。
