Borkenstein Andreas F, Borkenstein Eva-Maria, Omidi Pooria, Langenbucher Achim
Borkenstein & Borkenstein Private Practice, Graz, Austria.
Institute of Experimental Ophthalmology, Saarland University, Homburg, Germany.
Curr Eye Res. 2025 Jan;50(1):51-57. doi: 10.1080/02713683.2024.2391382. Epub 2024 Aug 14.
Neodymium yttrium aluminum garnet (Nd:YAG) laser capsulotomy is considered gold standard in the treatment of posterior capsule opacification (PCO). In this laboratory study, we measured spectral transmission to evaluate the image contrast and analyze the impact of Nd:YAG associated defects in presbyopia-correcting intraocular lenses (IOLs).
Two hydrophobic, acrylic IOLs as classic multifocal lenses with diffractive ring segments and different amount of near addition (A, B), one hydrophilic, trifocal IOL (C), one sector-shaped, plate haptic IOL (D) and one hydrophobic, enhanced depth of focus (EDOF) IOL (E) were studied. Measurements included surface topography characterization, United States Air Force resolution test chart (USAF) analysis, spectral transmittance measurements and through focus contrast measurement. Measurements were done with unaltered samples, damages ( = 7) were intentionally created in the central 3.5 mm zone using a photodisruption laser (2.0 mJ) and measurements were repeated.
Significant differences were shown between unmodified samples and samples with YAG pits. The YAG-pits decreased the image contrast and spectral transmission and changed results of USAF test images. The imaging contrast decreased to 66%, 64%, 60%, 52% and 59% with the YAG shots in samples (A-E). The light transmission decreased to 88%, 87%, 92%, 79% and 91% (A-E) on average between 400 nm to 800 nm. In all IOLs a reduction of the relative intensity of transmitted light was observed.
The image performance of all tested presbyopia-correcting IOLs is significantly influenced and disturbed by YAG-pits. The intensity of transmitted light is reduced in the wavelength between 450-800 nm. USAF test targets show worse results compared to unmodified samples and contrast is significantly deteriorated. No ranking/rating among tested IOLs should be made as many other factors play a role in real world scenario. High care should be taken when performing Nd:YAG capsulotomy on premium IOLs to avoid any damages.
钕钇铝石榴石（Nd:YAG）激光晶状体后囊切开术被认为是治疗后囊膜混浊（PCO）的金标准。在本实验室研究中，我们测量了光谱透射率以评估图像对比度，并分析Nd:YAG相关缺陷对矫正老花眼的人工晶状体（IOL）的影响。
研究了两种疏水性丙烯酸IOL，作为具有衍射环段和不同近附加度数的经典多焦点晶状体（A、B），一种亲水性三焦点IOL（C），一种扇形板袢IOL（D）和一种疏水性增强景深（EDOF）IOL（E）。测量包括表面形貌表征、美国空军分辨率测试图（USAF）分析、光谱透射率测量和全焦点对比度测量。对未改变的样品进行测量，使用光击穿激光（2.0 mJ）在中央3.5 mm区域故意造成损伤（=7处），并重复测量。
未改性样品与有YAG凹坑的样品之间存在显著差异。YAG凹坑降低了图像对比度和光谱透射率，并改变了USAF测试图像的结果。在样品（A-E）中进行YAG照射后，成像对比度分别降至66%、64%、60%、52%和59%。在400 nm至800 nm之间，光透射率平均降至88%、87%、92%、79%和91%（A-E）。在所有IOL中均观察到透射光相对强度的降低。
所有测试的矫正老花眼的IOL的图像性能均受到YAG凹坑的显著影响和干扰。在450-800 nm波长范围内，透射光强度降低。与未改性样品相比，USAF测试目标显示出更差的结果，对比度显著恶化。由于在实际情况中还有许多其他因素起作用，因此不应在测试的IOL之间进行排名/评级。对高端IOL进行Nd:YAG晶状体后囊切开术时应格外小心，以避免任何损伤。
