Belmont S C, Lazzaro D R, Muller J W, Troutman R C
New York Hospital-Cornell University Medical Center, NY, USA.
J Refract Surg. 1995 Nov-Dec;11(6):472-6. doi: 10.3928/1081-597X-19951101-14.
Videokeratography may provide information for surgical correction of astigmatism after penetrating keratoplasty. We used a combination of wedge resection and relaxing incisions to treat high refractive astigmatism after penetrating keratoplasty.
Videokeratography using the normalized scale of the Topographic Modeling System was used as a guide in determining the location and the length of incisions and resections. Nine eyes were treated with both relaxing incisions and a wedge resection. All patients had more than 3.00 diopters (D) of refractive astigmatism. All patients were intolerant of spectacles or contact lenses. The depth of the corneal relaxing incisions was constant at 0.5 mm and the width of the corneal wedge resections was constant at 0.75 mm.
The relaxing incisions produced flattening of the steeper meridian and the wedge resection produced steepening of the flatter meridian. The average preoperative keratometric astigmatism was 7.44 D (range, 3.50 to 11.00 D) and the average refractive astigmatism was 5.56 D (range, 4.00 to 8.00 D). The average preoperative spherical equivalent was 0.08 D (range, -7.00 to 4.25 D). Postoperatively, the average keratometric astigmatism was 2.97 D (range, 1.00 to 5.00 D) and the average refractive astigmatism was 2.58 D (range, 0.00 to 5.00 D). The average postoperative spherical equivalent refraction was -0.32 D.
Combined corneal wedge resection and relaxing incisions appears to be effective in reducing high refractive astigmatism following corneal transplantation.
角膜地形图仪可为穿透性角膜移植术后散光的手术矫正提供信息。我们采用楔形切除术和松解切口相结合的方法治疗穿透性角膜移植术后的高度屈光性散光。
使用地形建模系统的标准化量表进行角膜地形图检查,以此指导确定切口和切除术的位置及长度。9只眼接受了松解切口和楔形切除术。所有患者的屈光性散光均超过3.00屈光度(D)。所有患者均不耐受眼镜或隐形眼镜。角膜松解切口的深度恒定为0.5mm,角膜楔形切除术的宽度恒定为0.75mm。
松解切口使较陡子午线变平,楔形切除术使较平子午线变陡。术前平均角膜散光为7.44D(范围3.50至11.00D),平均屈光性散光为5.56D(范围4.00至8.00D)。术前平均等效球镜度为0.08D(范围-7.00至4.25D)。术后,平均角膜散光为2.97D(范围1.00至5.00D),平均屈光性散光为2.58D(范围0.00至5.00D)。术后平均等效球镜度为-0.32D。
角膜楔形切除术和松解切口相结合似乎对降低角膜移植术后的高度屈光性散光有效。