Karabatsas C H, Cook S D, Figueiredo F C, Diamond J P, Easty D L
Department of Ophthalmology, Bristol Eye Hospital, England.
Ophthalmology. 1998 Nov;105(11):1999-2006. doi: 10.1016/S0161-6420(98)91115-0.
To assess the effectiveness of computerized videokeratography (CVK) in refining the surgical design and in improving predictability of surgical correction of postkeratoplasty astigmatism.
A prospective, controlled, randomized, clinical trial.
A total of 31 postkeratoplasty eyes, divided into 2 groups (group A, 16 eyes; group B, 15 eyes), with more than 4 diopters (D) of disabling astigmatism were studied.
All eyes were treated with a combination of arcuate relaxing incisions and compression sutures. The surgical plan in group A was based on topographic information, whereas in the control group B, the surgical plan was based on information obtained by refraction and keratometry alone.
Change in the surgical plan induced by the CVK information, astigmatism, topographic patterns, and factors associated with outcome were measured.
In all 16 cases of group A, the use of CVK changed some aspect of the surgical plan. At 12 months after surgery, both groups showed a significant net reduction (P = 0.001) of baseline astigmatism. However, the reduction (47% and 41 % for groups A and B, respectively) did not differ significantly between the two groups. The topographic astigmatism at 12 months measured 4.24 +/- 0.71 D in group A and 5.60 +/- 0.51 D in group B (P = 0.139). Significant differences between the two groups at 12 months were seen only for keratometric astigmatism (3.60 +/- 0.81 D in group A vs. 5.77 +/- 0.52 D in group B, P = 0.035) and refractive astigmatism (2.34 +/- 0.37 D in group A vs. 4.88 +/- 0.52 D in group B, P = 0.000). The mean vector surgical effect was 91 % for group A and 70% for group B. Regular astigmatism patterns had a greater benefit from surgery than irregular patterns (P = 0.008). Previous refractive surgery was associated with less-favorable outcome (P = 0.045).
The current study indicates that the use of CVK provides a benefit compared to keratometry and refraction alone in the planning and outcome of surgical treatment for high postgraft astigmatism.
评估电脑化角膜地形图（CVK）在优化手术设计及提高角膜移植术后散光手术矫正可预测性方面的有效性。
一项前瞻性、对照、随机临床试验。
共31只角膜移植术后眼，分为2组（A组16只眼；B组15只眼），研究对象为散光度数超过4屈光度（D）且导致视力障碍的患者。
所有眼睛均采用弧形松解切口和压迫性缝线联合治疗。A组的手术方案基于地形信息，而对照组B的手术方案仅基于验光和角膜曲率计获得的信息。
测量由CVK信息引起的手术方案变化、散光、地形模式以及与手术结果相关的因素。
A组的所有16例病例中，CVK的使用改变了手术方案的某些方面。术后12个月，两组的基线散光均有显著净减少（P = 0.001）。然而，两组之间的减少幅度（A组和B组分别为47%和41%）无显著差异。A组术后12个月的地形性散光为4.24±0.71 D，B组为5.60±0.51 D（P = 0.139）。两组在术后12个月时的显著差异仅见于角膜曲率性散光（A组为3.60±0.81 D，B组为5.77±0.52 D，P = 0.035）和屈光性散光（A组为2.34±0.37 D，B组为4.88±0.52 D，P = 0.000）。A组的平均矢量手术效果为91%，B组为70%。规则散光模式从手术中获得的益处比不规则模式更大（P = 0.008）。既往屈光手术与较差的手术结果相关（P = 0.045）。
当前研究表明，与单独使用角膜曲率计和验光相比，在高植片散光的手术治疗规划和结果方面，使用CVK具有优势。
