Tehrani M, Schwenn O, Dick H B
John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA.
Klin Monbl Augenheilkd. 2001 Dec;218(12):795-9. doi: 10.1055/s-2001-19690.
After penetrating keratoplasty residual astigmatism can be treated with various options. Correction with spectacles or contact lenses, methods such as radial keratotomy, photorefractive keratectomy (PRK) or Laser-in-situ keratomileusis (LASIK) are limited only to mild and moderate astigmatism. In laser ablation a sufficient corneal thickness must be ensured. On the other hand surgical correction is performed on transplanted tissue which can increase the risk of allograft rejection. In pseudophakic eyes the implantation of an individually designed toric intraocular lens (IOL) according to keratometry and biometry with a cylindrical power up to 12 D provides an alternative method for correcting higher astigmatism. This individually designed IOL can be implanted additionally to the existing IOL.
A 66-year-old patient presented after penetrating keratoplasty and implantation of an IOL 4 years ago with a visual acuity of 20/160 and residual astigmatism of - 10 D x 151(o). After biometry an individually manufactured toric PMMA-IOL of + 12 D cylindrical and - 9.5 D spherical power was implanted via a sclerocorneal tunnel incision additionally to the existing IOL into the ciliary sulcus. Postoperatively a well centered and stable positioned IOL was found. One year after implantation of the toric IOL the position was still unchanged and the graft had remained clear. Spherical equivalent refraction was + 1,5 D - 3,0 D x 141(o), with an uncorrected visual acuity of 20/60.
Implantation of a toric intraocular lens in pseudophakic eyes allows the correction of high astigmatism after penetrating keratoplasty. The advantage of this method compared to the keratorefractive options lies in its minor manipulation on the allograft.
穿透性角膜移植术后残留散光可通过多种方法治疗。使用眼镜或隐形眼镜进行矫正,以及放射状角膜切开术、光性屈光性角膜切削术(PRK)或准分子原位角膜磨镶术(LASIK)等方法仅适用于轻度和中度散光。在激光消融术中,必须确保有足够的角膜厚度。另一方面,手术矫正针对的是移植组织,这可能会增加同种异体移植排斥反应的风险。在人工晶状体眼内,根据角膜曲率计测量和生物测量结果植入个性化设计的散光人工晶状体(IOL),其柱镜度数可达12 D,为矫正更高度数的散光提供了一种替代方法。这种个性化设计的IOL可额外植入到现有的IOL旁边。
一名66岁患者4年前接受了穿透性角膜移植术并植入了IOL,就诊时视力为20/160,残留散光为-10 D×151(o)。经过生物测量后,通过巩膜隧道切口,在现有的IOL旁边将一个柱镜度数为+12 D、球镜度数为-9.5 D的个性化制造的散光聚甲基丙烯酸甲酯人工晶状体植入睫状沟。术后发现人工晶状体居中良好且位置稳定。植入散光人工晶状体一年后,其位置仍未改变,移植片保持透明。等效球镜度为+1.5 D - 3.0 D×141(o),未矫正视力为20/60。
在人工晶状体眼中植入散光人工晶状体可矫正穿透性角膜移植术后的高度散光。与角膜屈光手术相比,该方法的优势在于对同种异体移植组织的操作较少。