Beheshtnejad Amir Houshang, Hani Mohammad, Abdolalizadeh Parya, Alipour Fateme
Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Department of Ophthalmology, School of Medicine, Urmia University of Medical Sciences, Urmia, Iran.
J Curr Ophthalmol. 2024 Oct 16;36(1):37-41. doi: 10.4103/joco.joco_169_23. eCollection 2024 Jan-Mar.
To compare the corneal epithelial thickness along the flat and steep meridians of corneas with low and high toricity.
This was a prospective observational comparative study on healthy subjects with normal corneas seeking preoperative evaluation for refractive surgery at a university-based hospital. Subjects with up to 2 diopters (D) of corneal with-the-rule astigmatism were defined as low corneal toricity (CT), whereas cylinder > two-dimensional was considered as high CT. The anterior segment optical coherence tomography was conducted to measure the epithelial thickness along the principle meridians of CT over a diameter of 9 mm. At the eye level, outcome variables (corneal and epithelial thicknesses in low- and high-astigmatism groups) were assessed using generalized estimating equation models.
Included were 98 eyes (49 subjects): 46 eyes (23 subjects) with low CT and 52 eyes (26 subjects) with high CT. Two groups were similar with respect to the age ( = 0.82), sex ( = 0.49), and spherical equivalent ( = 0.11). Although the corneal thickness at steep and flat meridians was not different between two groups, high-CT group had significantly thinner epithelium at inferior 2.5-3.5 and 3.5-4.5 mm zones ( = 0.01 and 0.04) as well as superior 2.5-3.5 mm zone ( = 0.03) along the steep meridian. Two groups were similar with respect to epithelial thickness of flat meridian (all > 0.05).
The epithelium of steep meridian was thinner in the high-CT group compared to the low-CT group.
比较低散光和高散光角膜在平坦和陡峭子午线上的角膜上皮厚度。
这是一项前瞻性观察性比较研究，对象为在一家大学附属医院寻求屈光手术术前评估的角膜正常的健康受试者。角膜顺规散光达2屈光度（D）的受试者被定义为低角膜散光（CT），而柱镜>2D被视为高CT。进行眼前节光学相干断层扫描，以测量9毫米直径范围内CT主要子午线上的上皮厚度。在眼水平，使用广义估计方程模型评估结果变量（低散光和高散光组的角膜和上皮厚度）。
纳入98只眼（49名受试者）：46只眼（23名受试者）为低CT，52只眼（26名受试者）为高CT。两组在年龄（P = 0.82）、性别（P = 0.49）和等效球镜度（P = 0.11）方面相似。尽管两组在陡峭和平坦子午线上的角膜厚度无差异，但高CT组在陡峭子午线下方2.5 - 3.5毫米和3.5 - 4.5毫米区域（P = 0.01和0.04）以及上方2.5 - 3.5毫米区域（P = 0.03）的上皮明显更薄。两组在平坦子午线的上皮厚度方面相似（均P>0.05）。
与低CT组相比，高CT组陡峭子午线的上皮更薄。
