Schneider Hanka, Stachs Oliver, Göbel Katja, Guthoff Rudolf
Department of Ophthalmology, Rostock University, Doberaner Strasse 140, 18055, Rostock, Germany.
Graefes Arch Clin Exp Ophthalmol. 2006 Mar;244(3):322-9. doi: 10.1007/s00417-004-1052-2. Epub 2005 Aug 17.
Modern cataract surgery is interested in recovery of the accommodative power. This investigation aimed at determining pseudophakic accommodation in subjects implanted with the accommodative Human Optics 1 CU intraocular lens after drug-induced ciliary muscle stimulation by measuring the objective refraction and the changes in anterior chamber depth in comparison with a PMMA intraocular lens with rigid haptics.
The studied sample involved 30 eyes of 30 patients undergoing cataract surgery due to age-related cataract. Patients were between 50 and 77 years of age (67.71 +/- 8.0). No randomization was performed. The 1 CU accommodative intraocular lens and the PMMA intraocular lens were implanted in 15 eyes of patients with an expected visual acuity of at least 0.7. Objective refraction under pilocarpine-stimulated ciliary muscle contraction was determined with a Hartinger coincidence refractometer. The anterior chamber depth was measured with Jäger's Haag-Streit slit-lamp attachment. The accommodative amplitude and the anterior chamber flattening were calculated from the measured values.
Twelve weeks after surgery the average accommodative amplitude in eyes with a 1 CU intraocular lens calculated from the refractive change under drug-induced stimulation was 0.48 +/- 0.36 D (with a maximum of 1.25 D). The measured change of anterior chamber depth under drug-induced stimulation was 0.3 +/- 0.32 mm (at a maximum of 0.9 mm). In the reference group with PMMA lenses, the mean accommodative amplitude derived from the refractive changes under drug-induced stimulation was 0.34 +/- 0.27 D (at a maximum of 0.85 D). The measured change in anterior chamber depth under drug-induced stimulation was 0.18 +/- 0.09 mm (at a maximum of 0.31 mm). No statistically significant differences were found between the two groups of lenses concerning change in anterior chamber depth and accommodative amplitude.
This investigations indicate a mean anterior 1 CU shift of only 0.32 mm and a maximum of 0.9 mm. The accommodative amplitudes measured with the Hartinger coincidence refractometer (mean value 0.47 D) correspond to these values. Similar conclusions may be drawn from existing investigative results of the reference group, which are on the same order of magnitude as those of the 1 CU group. Objective accommodation measurements are needed to evaluate commercially available accommodative intraocular lenses in a scientifically satisfactory manner. Objectively measurable parameters include changes of the anterior chamber depth as well as refraction, as determined for instance by coincidence refractometry and streak retinoscopy. Future studies should also consider the IOL properties, astigmatism, and pupillary diameter. This is the only way to identify pseudoaccommodation and a decisive factor for further development of accommodative artificial lenses.
现代白内障手术关注调节力的恢复。本研究旨在通过测量客观屈光度数和前房深度变化，确定在药物诱导睫状肌刺激后植入可调节的Human Optics 1 CU人工晶状体的受试者的人工晶状体调节能力，并与具有刚性襻的聚甲基丙烯酸甲酯（PMMA）人工晶状体进行比较。
研究样本包括30例因年龄相关性白内障接受白内障手术患者的30只眼。患者年龄在50至77岁之间（67.71±8.0）。未进行随机分组。将1 CU可调节人工晶状体和PMMA人工晶状体植入预期视力至少为0.7的15例患者眼中。使用Hartinger重合验光仪测定毛果芸香碱刺激睫状肌收缩时的客观屈光度数。使用耶格（Jäger）的 Haag-Streit裂隙灯附件测量前房深度。根据测量值计算调节幅度和前房变平情况。
手术后12周，根据药物诱导刺激下的屈光变化计算，植入1 CU人工晶状体的眼中平均调节幅度为0.48±0.36 D（最大值为1.25 D）。药物诱导刺激下测量的前房深度变化为0.3±0.32 mm（最大值为0.9 mm）。在PMMA人工晶状体的参照组中，根据药物诱导刺激下的屈光变化得出的平均调节幅度为0.34±0.27 D（最大值为0.85 D）。药物诱导刺激下测量的前房深度变化为0.18±0.09 mm（最大值为0.31 mm）。两组人工晶状体在前房深度变化和调节幅度方面未发现统计学上的显著差异。
本研究表明前房平均1 CU位移仅为0.32 mm，最大值为0.9 mm。用Hartinger重合验光仪测量的调节幅度（平均值0.47 D）与这些值相符。从参照组的现有研究结果中可得出类似结论，其与1 CU组的结果处于同一数量级。需要进行客观的调节测量，以便以科学上令人满意的方式评估市售的可调节人工晶状体。客观可测量参数包括前房深度变化以及屈光度数变化，例如通过重合验光法和带状检影法确定。未来的研究还应考虑人工晶状体特性、散光和瞳孔直径。这是识别假调节的唯一方法，也是可调节人工晶状体进一步发展的决定性因素。
