植入可调节人工晶状体和多焦点人工晶状体后视功能的对比研究

目的比较超声乳化白内障吸除术后植入可调节人工晶状体和多焦点人工晶状体的视功能。方法32例年龄相关性白内障患者根据自愿原则,采用非随机对照方式分成两组,试验组13例患者（24只眼）植入1CU可调节人工晶状体,对照组19例患者（30只眼）植入Array多焦点人工晶状体。术后3个月使用标准对数视力表检测患者最佳矫正视力及在最佳矫正视力基础上获得的近视力、近点及调节幅度、立体视觉。检查结果以年龄作为协变量,进行成组设计定量资料一元协方差分析。结果随诊期间所有患者均无明显的术后并发症。术后3个月试验组最佳矫正视力为4．96±0．15,对照组为5．02±0．08,两组比较差异无统计学意义（P=0．085）。试验组术后最佳矫正视力基础上获得的近视力为4．65±0．15,对照组为4．60±0．10,两组比较差异无统计学意义（P=0．398）。试验组术后主观近点为（56±9）cm,对照组为（61±11）cm,两组比较差异无统计学意义（P=0．80）。试验组术后调节幅度为（1．30±0．40）D,对照组为（1．20±0．36）D,两组比较差异无统计学意义（P=0．093）。试验组术后立体视觉为43．24”±18．25”,对照组为60．00”±23．09”,两组比较差异无统计学意义（P=0．543）。结论植入1CU可调节人工晶状体的患者术后可在保持最佳远视力的同时获得一定的近视力。两种人工晶状体在矫正远视力、远矫下近视力、主观近点、术后调节幅度及近距矫正基础上的立体视觉检查方面均无统计学意义。     

Stability of refraction, accommodation, and lens position after implantation of the 1CU accommodating posterior chamber intraocular lens

PURPOSE: To investigate stability of refraction, anterior chamber depth (ACD), and accommodation up to 12 months after implantation of the 1CU accommodating posterior chamber intraocular lens (PC IOL). SETTING: Department of Ophthalmology, University Erlangen-Nürnberg, Erlangen, Germany. METHODS: In a prospective study, 15 eyes of 15 patients (mean age 62.2 years +/- 13.4 [SD] [range 44 to 86 years]) had phacoemulsification and PC IOL implantation. Distance refraction, accommodative range measured by the near point with an accommodometer, ACD measured with the IOLMaster (Carl Zeiss Meditec), and near visual acuity with best distance correction (Birkh?user charts at 35 cm) were determined after 3, 6, and 12 months and analyzed for signs of systematic changes. RESULTS: After 3, 6, and 12 months, the mean distance refraction was -0.28 +/- 0.54 diopters (D), -0.29 +/- 0.52 D, and -0.21 +/- 0.54 D, respectively; the mean accommodative range, 1.93 +/- 0.47 D, 1.85 +/- 0.62 D, and 2.02 +/- 0.38 D, respectively; the mean ACD without pharmacological induction of ciliary muscle contraction, 4.40 +/- 0.44 mm, 4.35 +/- 0.50 mm, 4.25 +/- 0.53 mm, respectively; and the mean near visual acuity with best distance correction, 0.41 +/- 0.15, 0.37 +/- 0.12, and 0.39 +/- 0.11, respectively. There were no statistically significant changes in any measurement during the follow-up (P>.1). CONCLUSIONS: Refraction, ACD, and accommodative range remained stable without indication of a systemic trend toward myopia, hyperopia, PC IOL dislocation, or regression of accommodative properties. The 1CU accommodating PC IOL provided stable refraction, accommodation, and PC IOL position for up to 1 year.     

Comparison of 6-month results of implantation of the 1CU accommodative intraocular lens with conventional intraocular lenses

OBJECTIVE: To evaluate the clinical results of implantation of the new 1CU accommodative intraocular lens (IOL) in cataract patients and to compare results with those of conventional IOLs. DESIGN: Nonrandomized comparative trial. PARTICIPANTS: Twenty eyes of 20 patients (mean age = 65.8+/-13.3 years) in the 1CU group and 20 eyes of 20 patients (mean age = 67.4+/-11.6 years) in the control group. METHODS: All patients underwent phacoemulsification and IOL implantation. The 1CU accommodative lens was used in 20 eyes, and conventional IOLs (polymethyl methacrylate, hydrophilic or hydrophobic acrylate) were used in the control group. Patients were observed prospectively, and 6-month data were analyzed. MAIN OUTCOME MEASURES: Accommodative ranges determined by 3 different methods (near point, defocusing, and retinoscopy). Secondary outcome measures were (1) increase of anterior chamber depth after topical application of 1% cyclopentolate eyedrops and (2) distance-corrected near visual acuity with Birkh?user reading charts at 35 cm. RESULTS: We observed a higher accommodative range with all 3 methods (mean = 1.83+/-0.49 vs. 1.16+/-0.27 diopters [D] [near point], 1.85+/-0.43 vs. 0.64+/-0.21 D [defocusing], and 0.98+/-0.55 vs. 0.17+/-0.22 D [retinoscopy]), a larger increase of anterior chamber depth after cyclopentolate eyedrops (mean = 0.42+/-0.18 vs. 0.11+/-0.06 mm), and better distance-corrected near visual acuity (median = 0.4 vs. 0.2) in the 1CU group relative to the control group. All differences between the 2 groups were statistically highly significant (P<0.001). CONCLUSIONS: In the present study, the 1CU accommodative IOL showed increased accommodative range and better near visual acuity than a control group with conventional IOLs. Further research is necessary to confirm these results in masked, randomized, prospective studies and to confirm further the accommodative power of this group of new IOLs.     

Cardinal points and image–object magnification with an accommodative lens implant (1 CU)

A simple mathematical method for the determination of the cardinal points of pseudophakic eyes after implantation of an accommodative intraocular lens [posterior chamber intraocular lenses (PCIOL)] is presented. The purpose of this study was to explore the changes during pseudophakic accommodation (PAC) in (1). the positions of the cardinal points, (2). the distance of the object conjugate with the retina, and (3). the image-object magnification. These theoretical accommodation data are compared with clinical measurements. METHODS AND PATIENTS: Using biometrical measurements of the axial length, equivalent power of the cornea and the anterior chamber depth (ACD) in the non-accommodated state we used linear geometric optics for determination of the cardinal points and object distance as well as lateral magnification (the ratio of image to object size). With the measurement of ACD decrease (following pharmacological stimulation of the ciliary muscle with 2% pilocarpine eye drops) we determined the changes of the cardinal points and magnification to assess PAC amplitude from the shortening of the object distance. Calculated values of PAC amplitude were compared with the respective measured values derived from amplitude measures by accommodometer, defocusing and streak retinoscopy. We analysed the results of a prospective study on 35 eyes of 28 patients after cataract surgery (target refraction: -0.2 D) and accommodative PCIOL implantation (1 CU, Human Optics AG, Erlangen, Germany) 3 months after surgery. RESULTS: After pilocarpine eye drops, ACD (mean +/- S.D., range; median) decreased by 0.88 +/- 0.48 mm (0.51-1.91; 0.66). Distance of the in-focus object decreased from the non-accommodated state (-5.62 +/- 1.83 m, -25 to -1.1; -4.83 m) to the accommodated state (ACD decrease) (-0.81 +/- 0.21, -2.11 to -0.65; -0.79 m). For a theoretical ACD decrease of 1.0 mm (the intrinsic limitation of the PCIOL design) it was -0.59 +/- 0.28, -1.31 to -0.51; -0.63 m and resulted in an objective accommodative response of 1.49 +/- 0.16, 1.21-1.81; 1.46 D, depending on the actual geometry of the individual eye. On average, magnification as induced by PAC in contrast to that induced by adequate spectacle addition differed by only about 1%. Accommodation measured with defocusing and the accommodometer correlated significantly with the theoretical value based on IOLMaster measurement of ACD decrease (r = 0.752, p = 0.005 and r = 0.676, p = 0.02). Likewise, accommodation measured with streak retinoscopy correlated weakly with the theoretical value based on IOLMaster ACD decrease (r = 0.465, p = 0.05). CONCLUSIONS: Using geometrical optics, PAC can be derived from the biometric data of the eye and the measured ACD decrease. This approach may be an additional indicator for the accommodative response in pseudophakic patients and may allow a subdivision of the measured accommodation into true PAC and pseudoaccommodation, for example, because of increased depth of focus induced by pupillary constriction.     

Ultrasound biomicroscopic findings in aniridia

PURPOSE: To describe the ultrasound biomicroscopic features of eyes with aniridia. DESIGN: Observational case series. METHODS: Nineteen eyes of 10 patients with aniridia (six males and four females) ranging in age from 3 months to 53 years (21.0 +/- 16.4, mean +/- SD), and 50 normal subjects (30 men and 20 women) ranging from 16 to 56 years (31.1 +/- 13.2) were evaluated. Ultrasound biomicroscopic findings were recorded in the 3-, 6-, 9-, and 12-o'clock directions. Adult patients (aged 16 years or older) with aniridia were compared with the age-matched controls. RESULTS: Ultrasound biomicroscopy (UBM) detected extremely tiny irises in all eyes with aniridia. The eyes with aniridia showed significantly smaller values than the controls in ciliary body length (4.49 +/- 0.63 versus 5.79 +/- 0.44 mm, P <.001, unpaired Student t test), ciliary body thickness (0.75 +/- 0.17 versus 1.24 +/- 0.22 mm, P <.001), iris root thickness (0.47 +/- 0.14 versus 0.61 +/- 0.07 mm, P <.001), scleral-ciliary process angle (31.7 +/- 3.26 versus 43.1 +/- 4.48 degree, P <.001), and anterior chamber depth (1.99 +/- 0.43 versus 2.94 +/- 0.34 mm, P <.001). In the aniridia eyes, there was a significantly positive correlation between iris thickness and ciliary body thickness (Pearson r = 0.829, P =.001). CONCLUSION: Ultrasound biomicroscopic imaging demonstrated that not only iris hypoplasia but also ciliary body hypoplasia exist in aniridia. Anterior inclination of the ciliary process was also found, which was thought to be at least partly responsible for the shallow anterior chamber.     

Validity of anterior chamber depth measurements for the evaluation of accommodation after implantation of an accommodative Humanoptics 1CU intraocular lens

BACKGROUND: Changes in the anterior chamber depth (ACD) after pilocarpin application are generally regarded as reflecting an accommodative effect of accommodative intraocular lenses (IOLs) METHODS: We implanted Humanoptics 1CU accommodative IOLs into 25 eyes of 20 patients aged 53.2+/-14.7 years (range: 30-83 years). In seven of these patients, we were able to measure anterior chamber depth changes after the application of pilocarpine (2%) eye drops 3 months postoperatively using a Zeiss IOLMaster, an Orbscan II topography system, as well as by ultrasound biomicroscopy (20 MHz-US-head). RESULTS: Uncorrected near acuity was on average 0.4+/-0.23 (0.1-0.8) and uncorrected distance acuity was 0.76+/-0.23 (0.3-1). Before pilocarpine, ACD was 3.19+/-2.11 mm (IOL-Master), 3.35+/-2.22 mm (Orbscan II) and 3.35+/-2.21 mm (US-biomicroscopy) ( P=0.96). After pilocarpine, ACD was 2.61+/-1.71 mm (IOL-Master), 2.63+/-1.78 mm (Orbscan II) and 3.15+/-2.08 mm (US-biomicroscopy) ( P=0.002). The average individual ACD change before/after pilocarpine was 0.83+/-0.25 mm with the IOL-Master, 1.04+/-0.39 mm with the Orbscan II System and 0.28+/-0.14 with US-biomicroscopy ( P=0.0004). DISCUSSION: The 1CU Humanoptics accommodative IOL presented with potential accommodative capabilities in clinical evaluation. Drug induced accommodation by pilocarpine does not reflect real accommodative effects. The differences in ACD measurements between three different methods were statistically significant. Evaluation methods for accommodative IOLs should be carefully analysed and further development of objective means for evaluation is needed.     

Repeatability and validity of Zywave aberrometer measurements

PURPOSE: To study the repeatability of Zywave aberrometer (Bausch & Lomb) measurements and compare the measurements with those of subjective refraction and noncycloplegic and cycloplegic autorefractions in a clinical setting. SETTING: Department of Ophthalmology, University Hospital Maastricht, Maastricht, The Netherlands. METHODS: Subjective manifest refraction, noncycloplegic autorefraction, cycloplegic autorefraction, and Zywave aberrometer measurements were performed in 20 eyes of 20 myopic patients. Three consecutive Zywave measurements were performed with and without dilation of the pupil. The mean difference and 95% limits of agreement among the measurement methods were determined for dilated and 3.5 mm pupils. The repeatability coefficient of the Zywave aberrometer measurements was determined. RESULTS: The mean differences in spherical equivalent (SE), sphere, and cylinder between subjective refraction and Zywave predicted phoropter refraction (PPR) with a dilated pupil were -1.10 diopters (D) +/- 0.46 (SD) (P <.001), -1.08 +/- 0.44 D (P <.001), and -0.02 +/- 0.37 D (P =.87), respectively (paired Student t test). After the data were converted to a 3.5 mm pupil, the mean differences were -0.55 +/- 0.48 D (P <.001), -0.50 +/- 0.49 D (P <.001), and -0.16 +/- 0.50 D (P =.15), respectively. The mean difference in SE between autorefraction and cycloplegic autorefraction versus subjective refraction was +0.18 +/- 0.71 D (P =.27) and +0.35 +/- 0.62 D (P =.02), respectively. The mean difference in SE between cycloplegic autorefraction and Zywave PPR with a dilated pupil was -1.44 +/- 0.79 D (P <.001). The repeatability coefficient of Zywave PPR was +/-0.25 D for SE, +/-0.29 D for sphere, and +/-0.29 D for cylinder. CONCLUSIONS: Subjective refraction measurements are slightly more myopic than cycloplegic autorefraction measurements. With a dilated pupil, the Zywave measurements were significantly more myopic than subjective refractions and even more myopic than cycloplegic autorefractions. Zywave measurements and subjective refractions were in better agreement with a 3.5 mm pupil. The repeatability of Zywave aberrometer measurements is adequate for lower-order aberrations.     

Longterm results of 1 CU accommodative intraocular lens implantation: 2-year follow-up study

PURPOSE: To evaluate the longterm efficacy of 1 CU accommodative intraocular lenses (IOLs) to restore near visual performance. METHODS: This prospective study comprised 14 eyes previously included in a 6-month, case-control clinical trial, undergoing phacoemulsification and implantation of a 1 CU accommodative IOL. The main outcome measures were subjective refraction, uncorrected distance visual acuity (UCDVA), best corrected distance VA (BCDVA), distance-corrected near VA (DCNVA), best corrected near VA (BCNVA), and subjective amplitude of accommodation (AA). In addition, anterior and posterior capsule opacification were assessed. Patients were examined over a 2-year follow-up period. RESULTS: Distance and near visual performance worsened after 6 months. Uncorrected DVA and BCDVA were 0.8 +/- 2.1 and 1.0 +/- 0.8 at 6 months and 0.4 +/- 0.1 and 0.6 +/- 0.1 at 1 year, respectively (p = 0.001). Distance-corrected NVA and BCNVA were 3.7 +/- 2.1 Jaeger (J) and 1.0 +/- 0.7 J at 6 months and 8.1 +/- 0.7 J and 1.5 +/- 0.5 J at 1 year, respectively (p = 0.001). Anterior and posterior capsule opacification were present, respectively, in 28% and 21% of patients at 6 months and in 100% of patients at 1 and 2 years (p < 0.001). After Nd:YAG laser capsulotomy (performed in 100% of patients), UCDVA and BCDVA increased to 0.7 +/- 0.2 (p = 0.007) and 1.0 +/- 0.1 (p = 0.001), respectively, at 2 years. Distance-corrected NVA improved to 7.3 +/- 0.5 J (p = 0.006). Mean AA was 1.9 +/- 0.8 D at 6 months, 0.3 +/- 0.2 D (p = 0.004) at 1 year and 0.3 +/- 0.2 D at 2 years. CONCLUSIONS: Patients implanted with 1 CU IOLs lost their accommodation capacities with time because of the high incidence and degree of anterior and posterior capsule opacification. The accommodative lens material and design may have played a role in capsule fibrosis.     

First results of implantation of a new, potentially accommodative posterior chamber intraocular lens

PURPOSE: Conventional posterior chamber intraocular lenses (PCIOL) generally provide excellent visual acuity but do not restore accommodation. A new, potentially accommodative PCIOL has been designed after principles elaborated by K.D.Hanna using finite element models. However, before newly developed PCIOL may be implanted routinely in larger numbers of patients, careful and meticulous evaluation in clinical studies is necessary. Thus, it was the aim of this study to investigate intra- and early 3-month postoperative findings after implantation of the newly designed PCIOL. PATIENTS AND METHODS: In a prospective pilot and safety study that was approved by the ethics committee of our university, six eyes of six patients (2 males, 4 females, age range 54 to 87 years) with senile or presenile cataract underwent phacoemulsification and implantation of the new PCIOL by one surgeon between June and November 2000. The PCIOL (1 CU, HumanOptics AG, Erlangen, Germany) is a one-piece hydrophilic acrylic foldable lens with an optic diameter of 5.5 mm. Modified haptics are intended to allow anterior movement of the lens optic as a function of contraction of the ciliary muscle. Intra- and early postoperative findings obtained after one and two days, one, two and six weeks and 3 months postoperatively were documented prospectively. Postoperative examinations included recording of distance and near visual acuity both obtained with best distance correction, determination of subjective near point and measurement of distance and near refraction by streak retinoscopy. Follow-up was at least three months in all patients. RESULTS: Surgery was uncomplicated in all patients with successful in-the-bag implantation and good centration of the PCIOL. The postoperative course was uncomplicated without inflammation, hemorrhage, synechiae or decentration. Visual acuity improved in all patients according to the status of the macula with values between 20/200 (atrophic maculopathy) and 20/20. After three to six months we observed a difference between retinoscopic near and distance refraction of 0.625 to 1.875 D and subjective near points of 40 to 100 cm. Near visual acuity with distance correction ranged from 0.1 or J 16 (atrophic maculopathy) to 0.4 or J 7. CONCLUSIONS: These early and preliminary results of our small pilot study are encouraging. Our findings may indicate at least some degree of pseudophakic accommodation. However, further studies with additional methods of measurements, with longer follow-up, more patients and controlled studies with control groups are essential to further determine safety and potential accommodative power of this new PCIOL.     

角膜塑形术后眼前节形态及调节功能

目的研究近视儿童在配戴角膜塑形镜前及3个月后,调节反应及调节过程中眼前节形态的变化。方法前瞻性实验研究。本实验共纳入18名进展性近视青少年[（14.4±2.6）岁]作为研究对象。在配戴角膜塑形镜前及持续夜戴3个月后（摘镜后2 h内）,在采用Badal光学系统矫正受检者屈光不正的基础上,使用开放视野型红外验光仪分别在0 D、3 D和5 D的调节刺激下测量眼球屈光力,并计算调节反应量。同时使用实验室自行搭建的超长深度光学相干断层扫描仪（OCT）获取不同调节刺激下眼前节形态,每种刺激均重复拍摄2次。眼前节形态参数包括瞳孔直径（PD）、前房深度（ACD）、晶状体厚度（LT）以及晶状体前表面曲率半径（LAC）。分析戴镜前及戴镜3个月后调节反应及眼前节形态变化量的差异,数据采用配对t检验进行比较。结果在配戴角膜塑形镜3个月后,调节反应在3 D[（1.72±0.59）D vs. （2.42±0.84）D]和5 D[（3.09±0.63）D vs. （3.61±0.86）D]刺激下均显著增加,差异有统计学意义（t=2.84、2.12,P＜0.05）。戴镜3个月后,2种调节刺激下调节刺激前后的ΔACD、ΔLAC、ΔPD、ΔLT均较戴镜前变化更为显著。ΔACD[3 D：（-0.11±0.04）mm vs. （-0.16±0.06）mm,t=3.88,P＜0.01;5 D：（-0.15±0.05）mm vs. （-0.20±0.07）mm,t=2.37,P＜0.05]、ΔLAC[3 D：（-2.60±0.79）mm vs. （-3.81±1.08）mm,t=3.96,P＜0.01;5 D：（-3.57±1.14）mm vs. （-4.32±1.36）mm,t=2.08,P＜0.05]、ΔLT[3 D：（0.22±0.13）mm vs. （0.27±0.06）mm,t=-1.94,P＜0.05;5 D：（0.26±0.09）mm vs. （0.30±0.10）mm,t=-1.99,P＜0.05]在戴镜前后的差异均有统计学意义,而ΔPD仅在3 D[（-1.55±0.42）mm vs. （-1.71±0.37）mm]调节刺激下变化量具有统计学意义（t=1.76,P＜0.05）。结论配戴角膜塑形镜后,调节过程中调节反应及眼前节形态的变化幅度增大,调节滞后减少,调节功能得到改善。     

Accommodation after Nd: YAG capsulotomy in patients with accommodative posterior chamber lens 1CU

Purpose After initial encouraging results with the accommodative 1CU posterior chamber lens (PCIOL), we investigated the rate, the postoperative time point of posterior capsular opacification (PCO) necessitating YAG capsulotomy and the accommodative range after Nd: YAG capsulotomy in patients with 1CU-PCIOL.Patients and methods This prospective clinical study included 65 patients who underwent phacoemulsification and implantation of the accommodative 1CU-PCIOL with postoperative follow-up from 3 to 24 months. Postoperative examination was performed 3, 6 and 12 months after surgery, then before and 6 weeks after Nd: YAG capsulotomy. Measurements included: the best corrected distance visual acuity, distance refraction, near visual acuity (Birkhäuser charts in 35 cm) obtained with best distance correction, accommodative range measured by subjective near point with an accodommometer and defocusing with a visual acuity fall to 0.4.Results Both best corrected distance visual acuity (1.1±0.1) and near visual acuity with best distance correction (0.4±0.1) remained stable over the follow-up period until 12 months postoperatively. The accommodative range determined by near point was stable (mean 2.0±0.5 D). Also, the defocusing range remained stable over 12 months (1.8±0.4 D). A clinically relevant posterior capsule opacification with a significant decrease of visual acuity (0.4±0.2) and a need for Nd: YAG capsulotomy was diagnosed in 12 patients between 15 and 22 (mean 20±4, median 20) months postoperatively. All capsulotomies were performed without complication. Six weeks after capsulotomy, best corrected distance visual acuity was improved (1.1±0.1), near visual acuity with best distance correction was 0.4±0.1 and the accommodative range determined by near point was 1.95±0.6 D and by defocusing was 1.88±0.47 D. Six weeks after capsulotomy, measurements of the accommodative range did not show any statistical difference to the 12-month results before the occurrence of PCO (P>0.5).Conclusions A clinically relevant PCO with a significant decrease of visual acuity necessitating Nd: YAG capsulotomy occurred mainly after 15 postoperative months in patients with 1CU. Our results indicate that Nd: YAG capsulotomy may not affect the accommodation ability of the 1CU. Nevertheless, long-term studies are needed to further analyze the accommodative properties.     

Quality of vision following clinically successful penetrating keratoplasty

PURPOSE: To evaluate visual function following clinically successful penetrating keratoplasty (PKP). SETTING: Department of Ophthalmology, Ege University, School of Medicine, Izmir, Turkey. METHODS: Patient group (PG) included 9 patients (12 eyes) who had clinically successful PKP in our department. The control group (CG) included 12 people (18 eyes) who had no ocular disease other than refractive errors. Those with a visual acuity level less than 20/25 were not included in the study. Contrast sensitivity levels and light threshold values of the central retina were measured; scanning-slit corneal topography-pachymetry and aberrometric analysis were performed. RESULTS: There were no statistical difference in terms of age (32.55 years +/- 9.25 (SD) in PG, 36.75 +/- 5.85 years in CG; P =.53), cylinder power in plus form (2.60 +/- 1.25 diopter (D) in PG, 2.79 D +/- 2.51 D in CG; P =.88), and spherical equivalent of refractive errors (-3.66 +/- 3.57 D in PG, -5.52 +/- 3.37 D in CG; P =.29) between the PG and CG. Cambridge low-contrast grating scores were 96.5 +/- 41.1 in grafted eyes and 148 +/- 27.7 in CG (P =.004). Central retinal light sensitivity was measured as 29.91 +/- 2.39 db in PG and 33.08 +/- 1.56 db in CG (P =.001). In corneal topographic analysis, mean kappa intercept was 0.69 +/- 0.37 mm in PG and 0.55 +/- 0.24 mm in CG (P =.20). Lower-order Zernike root mean squares (RMS) were 7.30 +/- 3.89 microm for PG and 8.58 +/- 3.46 microm for CG (P =.37). However, higher-order Zernike RMS were 2.15 +/- 0.78 in PG and 0.38 +/- 0.10 in CG, which is a statistically significant difference (P<.001). CONCLUSIONS: Even though the clinically successful PKP patients have correctable amount of spherocylindrical refractive errors with spectacle lenses, they still have reduced visual quality because of the significantly high amount of higher- order aberrations when compared with naturally occurring refractive errors.     

可调节人工晶状体植入术的早期疗效观察

目的探讨超声乳化白内障吸除可调节人工晶状体植入术的临床疗效和调节幅度。方法对75例(94只眼)白内障患者行超声乳化白内障吸除1CU型可调节人工晶状体植入术,观察并记录术眼的主观屈光状态、裸眼远视力、裸眼近视力、最佳矫正远视力、30cm处远视力矫正后近视力、30cm处最佳矫正近视力、主观调节幅度(分别采用主观移近法和负镜片法测量)。术后随访时间1～12个月,对术后1周、1个月及3个月的资料进行分析。结果术后1周、1个月及3个月裸眼近视力≥Jr5者分别占81.9%(77/94)、85.1%(80/94)及84.0%(79/94);远视力矫正后近视力≥Jr5者分别占78.7%(74/94)、79.8%(75/94)及74.5%(70/94)。采用主观移近法和负镜片法检查调节幅度,术后1周分别为(1.96±0.63)D(0.75～4.50D)和(1.74±0.59)D(0.75～4.50D),术后1个月分别为(1.89±0.54)D(0.75～3.25D)和(1.68±0.47)D(0.75～3.25D),术后3个月分别为(1.77±0.53)D(0.75～2.75D)和(1.66±0.50)D(0.75～2.75D)。术后1周、1个月及3个月2种方法测量的主观调节幅度比较,差异均无统计学意义(P>0.05)。远视力矫正后近视力和调节幅度之间为正相关(P=0.00)。结论早期观察结果显示1CU型可调节人工晶状体植入术后视功能恢复良好,患者在具有较好远视力的同时,具备良好的视近能力。远期效果有待进一步观察。     

Intraocular pressure after phacoemulsification and intraocular lens implantation in nonglaucomatous eyes with and without exfoliation

PURPOSE: To evaluate intraocular pressure (IOP) after phacoemulsification and intraocular lens (IOL) implantation in nonglaucomatous eyes with and without exfoliation. SETTING: Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland. METHODS: One hundred ninety-six eyes that had phacoemulsification with IOL implantation were examined. Eyes with a history of intraocular disease or surgery that could affect IOP were excluded. The study comprised the remaining 160 eyes: 23 with exfoliation (EXF group) and 137 without exfoliation (non-EXF group). Follow-up data were available for 136 eyes. The same surgeon performed all surgeries. Patients were examined on the first postoperative day and after 1 week, 4 months, and 1.0 to 2.7 years. RESULTS: One day postoperatively, IOP rose in the EXF group from a mean preoperative level of 16.3 mm Hg +/- 2.7 (SD) to 21.0 +/- 8.5 mm Hg, a 28.4% increase (P =.0061). In the non-EXF group, mean IOP rose from 16.2 +/- 3.4 mm Hg to 20.5 +/- 5.7 mm Hg, a 29.9% increase (P =.001). In 4 eyes (17.4%) in the EXF group and 8 eyes (5.8%) in the non-EXF group, IOP increased to 30 mm Hg or higher at 1 day. After this, significant IOP decreases occurred in both the EXF and non-EXF group, respectively, as follows: 14.2 +/- 3.0 mm Hg (12.0% decrease from preoperative value; P =.001) and 15.0 +/- 2.9 mm Hg (5.9%; P =.001) 1 week postoperatively; 12.8 +/- 2.7 mm Hg (20.2%; P =.0002) and 13.8 +/- 2.7 mm Hg (13.2%; P =.001) after 4 months; and 12.3 +/- 2.6 mm Hg (23.2%; P =.0001) and 12.7 +/- 2.7 mm Hg (21.2%; P =.001) after 1.0 to 2.7 years. There was no significant difference between the 2 groups. CONCLUSION: After phacoemulsification with IOL implantation, IOP decreased significantly and remained lower than preoperatively in eyes with and without exfoliation. One day postoperatively, transient pressure peaks were more common in eyes with exfoliation. One eye without exfoliation developed glaucoma.     

Efficacy of glaucoma filtration surgery in pseudophakic patients with or without conjunctival scarring

PURPOSE: To analyze the intraocular pressure (IOP), glaucoma medication requirements, and visual acuity after glaucoma filtration surgery in pseudophakic eyes. SETTING: Private practice, Boston, Massachusetts, USA. METHODS: The results of glaucoma filtration surgery in 47 eyes of 40 pseudophakic patients with a minimum follow-up of 1 year were retrospectively reviewed. Eyes with previously surgically manipulated conjunctiva in the area of filtration were compared to eyes without previous manipulation. RESULTS: Preoperatively, the mean IOP was 25 mm Hg +/- 7.3 (SD); mean number of glaucoma medications, 3.3 +/- 1.0; and mean logMAR visual acuity, 0.41 +/- 0.38. At the final follow-up visit (mean 36.5 +/- 31.5 months), the respective means were 13.6 +/- 6.6 mm Hg (P<.001), 0.9 +/- 1.4 (P<.001), and 0.46 +/- 0.43 (P=.53). The mean postoperative IOP, glaucoma medication requirements, and visual acuity at the final follow-up in eyes with virgin conjunctiva and eyes with previously manipulated conjunctiva were, respectively, as follows: IOP, 12.5 +/- 3.2 mm Hg and 14.1 +/- 7.6 mm Hg (P=.52); medications, 1.1 +/- 1.3 and 0.9 +/- 1.4 (P=.66); and logMAR acuity, 0.6 +/- 0.52 and 0.4 +/- 0.39 (P=.23). CONCLUSIONS: Glaucoma filtration surgery in pseudophakic eyes significantly improved IOP and reduced glaucoma medication requirements while maintaining stability of vision. There were no statistically significant differences in final IOP, glaucoma medication requirements, or visual acuity between eyes with virgin conjunctiva and eyes with previously surgically manipulated conjunctiva.     

Late dislocation of scleral-sutured posterior chamber intraocular lenses

PURPOSE: To examine a recent series of late scleral-sutured posterior chamber intraocular lens (PCIOL) dislocations to identify possible causes and preventive measures. SETTING: Price Vision Group, Indianapolis, Indiana, USA. METHODS: In this retrospective non-comparative interventional case series, 5 consecutive patients received treatment for dislocated scleral-sutured PCIOLs between July 2002 and March 2004. Dislocated lenses were resutured or replaced with another scleral-sutured PCIOL. RESULTS: Dislocation of scleral-sutured PCIOLs occurred 7 to 14 years after implantation. Four dislocations were spontaneous, and 1 was precipitated by trauma. In each case, the suture affixing 1 or both haptics failed. There was no evidence that the suture had eroded through the tissue or that the knot had untied. Microscopic analysis of an explanted IOL with remnants of the suture attached showed localized degradation and cracking of the polypropylene suture material where it had been embedded in the scleral tissue. CONCLUSION: Suture-fixated PCIOLs can dislocate due to degradation of the suture material over time. The use of larger diameter (9-0 instead of 10-0) polypropylene suture material and placement of the haptic and sutures in the ciliary sulcus to promote attachment of scar tissue may enhance the long-term stability of scleral-fixated PCIOLs.     

Keratocyte density in keratoconus. A confocal microscopy study(a)

PURPOSE: To estimate keratocyte density in human corneas with keratoconus by confocal microscopy. DESIGN: Prospective, observational cohort study. METHODS: Twenty-nine unscarred corneas of 19 patients with keratoconus and 29 corneas of 19 controls matched for age (+/-3 years) and contact lens wear were examined by using confocal microscopy. Images were recorded from the full-thickness central cornea. A masked observer manually counted bright objects (keratocyte nuclei) in images without motion blur. Cell densities in anteroposterior stromal layers of keratoconus corneas were compared with densities in corresponding layers of control corneas. RESULTS: In keratoconus patients, age 40 +/- 15 years (mean +/- standard deviation), keratocyte density was 19% lower in those who wore contact lenses (16,894 +/- 4032 cell/mm(3), n = 12) than in those who did not wear contact lenses (20,827 +/- 4934 cell/mm(3), n = 17, P =.03). In control patients, age 39 +/- 16 years, there was no difference in keratocyte density between those who wore contact lenses (n = 12) and those who did not wear contact lenses (n = 17, P =.80). Among contact lens wearers, keratocyte density was 25% lower in keratoconus corneas (16,894 +/- 4, 032 cell/mm(3), n = 12 [9 = rigid gas-permeable lenses, 3 = soft lenses]) than in control corneas (22,579 +/- 2, 387 cell/mm(3), n = 12 [3 = rigid gas-permeable lenses, 9 = soft lenses], P =.002), the result of cell density being lower in the most anterior keratocyte layer (P =.001) and the layers between 0% to 10% (P <.001), 67% to 90% (P <.001), and 91% to 100% (P <.001) of stromal thickness. Among noncontact lens wearers, there was no difference in cell density between keratoconus and controls (P =.41). CONCLUSION: Keratocyte density is decreased in the anterior and posterior stroma of keratoconus patients who wear contact lenses.     

两种拟调节型人工晶状体植入术后视功能对比分析

目的 比较超声乳化术后植入可调节人工晶状体和多焦点人工晶状体的视功能.方法 30例白内障患者按自愿原则,采用非随机对照方式分成两组,试验组①10例患者(10只眼)植入Tetraflex可调节人工晶状体.试验组②20例患者(30只眼)植入+3.0D ReSTOR多焦点人工晶状体.术后6个月以ETDRS视力表检测患者最佳矫正远视力及在最佳矫正远视力基础上获得的近视力、中距离视力,综合验光仪检测近点及调节幅度.结果 随访期间所有患者均无明显的术后并发症.试验组①最佳矫正远视力为(-0.21±0.06)LogMAR,近视力为J3/40cm,试验组②为(-0.23±0.09)LogMAR,近视力为J1/35cm,两组比较近视力差异有统计学意义(P=0.035).试验组①术后主观近点为(39±10)cm,试验组②为(35±9)cm,两组比较差异无统计学意义(P=0.80).试验组①术后调节幅度为(1.94±0.13)D,试验组②为(2.08±0.63)D,两组比较差异有统计学意义(P=0.048).结论 可调节人工晶状体与多焦点人工晶状体植入术后均可使患者的视近困难得以改善.医生应根据患者情况为其选择合适的人工晶状体.

Abstract：

Objective To compare the visual performance of accommodative IOLS and that of multifocal IOLs implantation after phacoemulsification. Methods A total of 40 eyes from 30 patients undergoing phacoemulsification received intraocular lens based on the principle of voluntary. Ten eyes from 20 patients who had implantation of Tetraflex accommodative intraocular lens were randomized into group 1. Thirty eyes from 20 patients who had implantation of +3.0 aspheric ReSTOR multifocal intraocular lens were randomized into group 2. Main outcome measures included best corrected distance visual acuity, distance corrected near vision, near point, intermediate vision, and the accommodation amplitude. All the clinical data were obtained at 6months postoperatively. Results No patients had undergone any complications. At 6 months postoperatively,best corrected distance visual acuity were similar between the groupl and group2 (-0.23± 0.09LogMAR versus-0.14 ± 0.08LogMAR, P =0.085). Distance corrected near vision were similar between the two groups (J3/40cm versusJ1/35cm, P =0.035). Subjective near point were similar between the two groups [(39± 10) cm versus (35± 9) cm F=0.065, P=0.80]. The accommodation amplitude were similar between the two groups [(1.94± 0.13)D versus (2.08± 0.63)D, P =0.093]. The defocus line showed a double-peak in group 2 and single peak in group 1 which declined at intermediate distance. Conclusions Both accommodative IOLs and multifocal IOLs can correct presbyopia effectively after operation. It is best to prefer the proper IOLs for patients.     

Effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis

PURPOSE: To assess effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis (LASIK). DESIGN: Prospective, nonrandomized clinical trial. METHODS: We examined 27 eyes with mean myopic regression +/- standard deviation of -1.26 +/- 0.48 diopters (D; range, -0.50 to -2.25 D) after LASIK. Nipradilol 2.5% was administered topically twice daily to these regressive eyes. We obtained the refraction (spherical equivalent, astigmatism), intraocular pressure (IOP) measurements, pachymetry, geometry, and refractive power of the cornea before and three months after treatment. RESULTS: Mean manifest refraction was improved significantly from -1.02 +/- 0.52 D to -0.44 +/- 0.39 D (P < .001). However, mean manifest astigmatism was changed from -0.55 +/- 0.30 D to -0.49 +/- 0.22 D, but the difference was not significant (P = .23). The IOP was decreased significantly from 11.4 +/- 2.4 mm Hg to 9.4 +/- 1.3 mm Hg (P < .001). Central corneal thickness was not changed significantly from 505.2 +/- 39.3 microm to 503.6 +/- 38.7 microm (P = .61). The posterior corneal surface was shifted posteriorly by 9.1 +/- 8.2 microm, and the total refractive power of the cornea was decreased significantly, by 0.63 +/- 0.62 D (P < .001), at three months after application. CONCLUSIONS: The preliminary data show that antiglaucoma drugs are effective for the reduction of the refractive regression, especially of the spherical errors, after LASIK. It is suggested that backward movement of the cornea may occur, possibly flattening the corneal curvature by lowering the IOP. Reduction of the IOP may contribute to improving regression after keratorefractive surgery.     

Efficacy of anterior chamber decompression in controlling early intraocular pressure spikes after uneventful phacoemulsification

PURPOSE: To determine the efficacy of anterior chamber decompression in the management of intraocular pressure (IOP) spikes in the early period after uneventful phacoemulsification. SETTING: Royal Free Hospital, Department of Ophthalmology, Royal Free and University College London Medical School, London, United Kingdom. METHODS: This prospective case series comprised 11 consecutive patients with otherwise healthy eyes who an IOP of at least 40 mm Hg 4 to 6 hours after phacoemulsification. After anterior chamber decompression, the IOP was measured at 0, 15, 30, 45, and 60 minutes or until it exceeded 40 mm Hg. RESULTS: The mean IOP 4 to 6 hours postoperatively was 47.09 mm Hg +/- 7.92 (SD) (range 40 to 68 mm Hg). After decompression, the IOP dropped significantly to a mean of 4.73 +/- 3.00 mm Hg at 0 minutes (P<.001) and then increased progressively to 23.36 +/- 10.80 mm Hg at 15 minutes (P<.001), 33.82 +/- 11.74 mm Hg at 30 minutes (P=.005), 35.00 +/- 6.53 mm Hg at 45 minutes (P=.015), and 38.50 +/- 2.51 mm Hg at 60 minutes (P=.041). CONCLUSIONS: Marked IOP spikes developed in eyes without glaucoma or ocular hypertension after uneventful phacoemulsification. Anterior chamber decompression immediately lowered IOP, but the effect was transient.