Virginia Mason Medical Center, Seattle, Washington.
Ophthalmology. 2015 May;122(5):897-902. doi: 10.1016/j.ophtha.2014.12.002. Epub 2015 Jan 17.
To compare final spherical equivalent (SE) refractions in patients who previously underwent radial keratotomy (RK) undergoing routine cataract surgery using keratometry (K) values from the Tomey (Topographic Modeling System [TMS]; Tomey Corp., Phoenix, AZ) Placido topographer, manual keratometer, and IOLMaster (Carl Zeiss Meditec AG, Jena, Germany) keratometer using the Haigis formulas.
Retrospective case series.
A total of 26 RK eyes (20 patients) with a minimum of 3 months postoperative follow-up.
The following K values were evaluated: TMS topography (flattest K within first 9 rings, average K, minimum K), manual K, IOLMaster K. The final refractive goal was -0.50 diopters (D) for all eyes. The Haigis formula with target refraction -0.50 D was used. In addition, because of observed hyperopic overcorrections, IOLMaster K with the Haigis formula set to -1.00 D but with a final refractive goal of -0.50 D was also tested. The Haigis-L formula using IOLMaster K values was separately evaluated.
Mean final SE refraction, percent final SE within ideal (-0.12 to -1.00 D), acceptable (0.25 to -1.50 D), or unacceptable (<-1.50 or >0.25 D) range and within ±0.50 D and ±1.00 D of the intended result.
Best results with minimal overcorrections were achieved with TMS flattest K (mean -0.68±0.60 D, 73% within ±0.50 D, and 88% within ±1.00 D of the surgical goal) and IOLMaster K set for target -1.00 D (mean -0.66±0.61 D, 69% within ±0.50 D, and 88% within ±1.00 D of the surgical goal). Other values produced more hyperopic (manual, IOLMaster K set for target -0.50 D, average topography) or higher myopic (minimum topography, Haigis-L) results.
For simplicity, using the IOLMaster K values combined with the Haigis formula set for target refraction -1.00 D produces acceptable results aiming for -0.50 D final SE refractions in former RK patients undergoing routine cataract surgery.
比较在接受常规白内障手术的既往行放射状角膜切开术(RK)患者中,使用 Tomy(TMS)角膜地形图仪(Tomey 公司,凤凰城,AZ)、手动角膜曲率计和 IOLMaster(卡尔蔡司 Meditec AG,耶拿,德国)角膜曲率计中的角膜曲率(K)值,根据 Haigis 公式,对之前行放射状角膜切开术的患者进行常规白内障手术时的最终球镜等效(SE)折射。
回顾性病例系列。
26 只 RK 眼(20 例),术后至少随访 3 个月。
评估以下 K 值:TMS 地形图(前 9 个环内最平坦的 K 值、平均 K 值、最小 K 值)、手动 K 值、IOLMaster K 值。所有眼的最终屈光目标均为-0.50 屈光度(D)。使用目标折射-0.50 D 的 Haigis 公式。此外,由于观察到远视过矫,还测试了将 IOLMaster K 设置为-1.00 D 但最终屈光目标为-0.50 D 的 Haigis 公式。还分别评估了使用 IOLMaster K 值的 Haigis-L 公式。
平均最终 SE 折射、最终 SE 在理想范围内(-0.12 至-1.00 D)的百分比、可接受范围(0.25 至-1.50 D)、不可接受范围(<-1.50 或>0.25 D)以及在±0.50 D 和±1.00 D 范围内的百分比,与预期结果的差异。
使用 TMS 最平坦 K(平均-0.68±0.60 D,73%在±0.50 D 内,88%在±1.00 D 内)和目标为-1.00 D 的 IOLMaster K(平均-0.66±0.61 D,73%在±0.50 D 内,88%在±1.00 D 内)可以获得最佳的低矫正效果。其他值产生更远视(手动,目标为-0.50 D 的 IOLMaster K 设置,平均地形图)或更高近视(最小地形图,Haigis-L)的结果。
为了简单起见,使用 IOLMaster K 值并结合目标折射-1.00 D 的 Haigis 公式,可以为接受常规白内障手术的既往 RK 患者产生可接受的结果,目标为-0.50 D 的最终 SE 折射。