两种TECNIS多焦点人工晶状体不同组合方式植入术后视力对比

目的:对比双眼均植入Tecnis Symfony ZXR00(ZXR00)、双眼分别植入ZXR00和Tecnis ZMB00(ZMB00)以及双眼均植入ZMB00患者术后视力、视觉质量及患者满意度。方法:回顾性病例对照研究。收集2020-08/2021-12行白内障超声乳化吸除联合人工晶状体(IOL)植入的白内障患者117例(234眼),根据IOL不同分为三组:37例(74眼)双眼植入ZMB00为MM组;44例(88眼)双眼分别植入ZXR00和ZMB00为MR组;36例(72眼)双眼均植入ZXR00为RR组。观察三组患者术后3 mo裸眼远视力(UDVA,5 m)、裸眼中视力(UIVA,80 cm)、裸眼近视力(UNVA,40 cm)、矫正远视力(CDVA)、离焦曲线、立体视及VF-14、QoV视觉质量评分表问卷调查。结果:MM和MR组UNVA优于RR组(P<0.05);而MM组与MR组不具有统计学差异。RR组UIVA最优。三组的UDVA、CDVA和立体视均不具有统计学意义(P>0.05)。术后3 mo时MR、MM、RR组40 cm近立体视锐度分别为107.27±80.53、105.67±83.79、108.69±97.66 (20-400)弧秒(P> 0.05)。MR、MM、RR组的满意度均达到90%以上。结论:三组术后均具有良好的远、中、近视力和双眼近立体视。其中,MR组具有更优异的全程视力。三组患者术后满意度均较高,可以根据患者的不同需求选择合适的多焦点人工晶状体。

微单视设计双眼连续视程人工晶体植入术后视觉质量分析

目的 评估微单视设计双眼植入连续视程人工晶体后患者视觉质量及满意度。方法 本研究为前瞻性研究,招募2021年8月至12月在四川省人民医院眼科接受手术的40位患者。术前测主视眼,术后第1天、1周、1个月和3个月进行随访。指标:双眼裸眼视力;离焦曲线;OQAS视觉质量;满意度问卷。结果 患者术后视力提高,全程视力表现平稳;客观散射指数、调制传递函数截止频率、斯特列尔比值、模拟对比度视力的差异无统计学意义(P<0.05为有统计学意义);个别患者有光晕、眩光不适,但总体脱镜率高,满意度高。结论 本设计中患者满意度高,可完善围手术期评估与治疗后进一步推广。

基于离散面阵的超大规模MIMO近场性能分析

超大规模多输入多输出(Extremely Large-scale Multiple-Input Multiple-Output, XL-MIMO)技术由于其带来新的近场球面波传播特性,有望大幅提升无线通信系统容量而受到广泛关注。然而,现有研究主要集中于基于均匀线性阵列(Uniform Linear Arrays, ULA)的XL-MIMO系统。针对更一般的基于均匀平面阵列(Uniform Planar Arrays, UPA)的XL-MIMO系统,推导出近场有效自由度(Effective Degrees of Freedom, EDoF)的解析表达式,得到信道容量的解析表达式。通过仿真,验证了所得表达式的准确性,同时揭示了通信距离和天线阵列尺寸等关键因素对XL-MIMO系统近场通信性能的影响机理。

多天线系统中的多维极化分集性能分析

分别研究了六维极化元天线和三维极化偶极子天线模型的空域相关矩阵,计算了系统的信道容量和有效空间自由度(EDOF)。通过定义更广义的角谱分布,指出了在六维极化的元天线模型中,平均入射角对系统性能起着关键的作用,而入射角谱的对称性也是导致元天线模型中低相关性的主要原因;通过对三维正交极化的半波偶极子结合矩量法和蒙特卡罗方法计算,论证了在散射丰富条件下应用三维极化天线,可获得接近三倍单天线信道容量的增益,从而验证了已有的测试结果;最后给出了三维正交极化天线的设计思路。

相关信道下多模式天线选择算法的研究

分析了相关信道情况下,角度扩散对信道增益及有效自由度的影响,提出了基于有效自由度的多模式天线选择算法,该算法不仅可以根据信道相关情况动态选择天线数目,而且可以基于信道条件数动态确定天线子阵。仿真实验表明,采用该天线选择算法后香农信道容量与使用全部天线时的信道容量相比,损失很小,而系统复杂度降低。

Clinical Outcomes with a New Model of Extended Depth of Focus Intraocular Lens

Purpose: To evaluate the early clinical outcomes of a new diffractive extended depth-of-focus (EDOF) intraocular lens (IOL). Methods: Prospective case series enrolling patients undergoing cataract surgery with implantation of the EDOF IOL AT LARA (Carl Zeiss Meditec, Jena, Germany). Distance, intermediate and near visual acuity were evaluated during a follow-up of 1 month. Likewise, defocus curve, binocular mesopic contrast sensitivity, perception of photic phenomena, patient satisfaction and spectacle independence were assessed. Results: The study enrolled 38 eyes of 19 patients with a mean age of 69.5 years. A significant reduction of manifest refraction and improvement in corrected distance visual acuity (CDVA) was observed with surgery (p < 0.001). All eyes achieved a 1-month postoperative binocular CDVA of 20/20 or better. Likewise, all eyes achieved a DCIVA of 20/30 or better at 1 month postoperatively, and a total of 92.1% achieved DCNVA of 20/40 or better. Concerning refractive predictability, 97.4% of eyes had a 1-month postoperative spherical equivalent within ±0.50 D. The level of patient satisfaction with distance, intermediate and near vision was high, with 95% of patients reporting that they would have the same surgical procedure with the same IOL again. Difficulties in night driving or associated to halos were low. A total of 89% of patients reported to be spectacle independent postoperatively. Conclusions: The EDOF IOL AT LARA is able to provide a functional restoration of the visual function across distances after cataract surgery, with very high levels of patient satisfaction and minimal incidence of photic phenomena.

Investigation into the Performance of a MIMO System Equipped with ULA or UCA Antennas: BER, Capacity and Channel Estimation

This paper reports on investigations into the performance of a Multiple Input Multiple Output (MIMO) wireless communication system employing a uniform linear array (ULA) at the transmitter and either a uni-form linear array (ULA) or a uniform circular array (UCA) antenna at the receiver. The transmitter is as-sumed to be surrounded by scattering objects while the receiver is postulated to be free from scattering ob-jects. The Laplacian distribution of angle of arrival (AOA) of a signal reaching the receiver is postulated. The performance of bit error rate (BER), capacity and channel estimation for a MIMO system are evaluated for the two cases that the receiver is equipped with ULA or with UCA antennas.

Visual Performance of a Polynomial Extended Depth of Focus Intraocular Lens

Purpose: To clinically evaluate a new extended depth of focus intraocular lens (ISOPURE, PhysIOL) with optic design modification based on a unique polynomial concept to improve intermediate vision while keeping the quality of distance vision equal to a monofocal lens. Methods: 18 patients (11 female, 7 male, mean age of 69.4 years) with bilateral cataract and regular corneal astigmatism ≤ 1.0 D underwent bilateral cataract surgery with ISOPURE implantation. Patients were followed for up to 6 months. Measured parameters were uncorrected (UDVA) and corrected distance visual acuity (CDVA), uncorrected (UIVA) and distance-corrected intermediate visual acuity at 80 cm and 66 cm (DCI80VA, DCI66VA) subjective refraction, defocus curve, tolerance of cylinder induction, and contrast sensitivity. The data from all implanted eyes (all-eyes) and a subset only including the first eye implanted for each patient were analysed. Results: The mean manifest refraction spherical equivalent (MRSE) decreased from 1.05 D pre-operatively to ?0.15 D at the 4 - 6 month assessment, with 80.6% of eyes within ±0.50 D of emmetropia. At the final follow-up, mean (SD) monocular CDVA was ?0.06 (0.04) logMAR, DCI80VA was 0.18 (0.08) logMAR and DCI66VA was 0.27 (0.13) logMAR. Despite a cylinder induction of ?0.50 D, uncorrected distance visual acuity of 0.02 logMAR was still achieved. Conclusion: The ISOPURE intraocular lens provides excellent distance corrected visual acuity for far and intermediate distances along with high contrast sensitivity and good tolerance of residual refractive cylinder.

The relationship between patient satisfaction and visual and optical outcome after bilateral implantation of an extended depth of focus multifocal intraocular lens

Purpose:To evaluate patient satisfaction after implantation of the Tecnis Symfony multifocal intraocular lens(MIOL).Methods:120 eyes of 60 subjects with senile cataract were bilaterally implanted with the Tecnis Symfony IOL.Follow-up examination was performed 6 months postoperatively.Main outcome measures included uncorrected and corrected distance and near visual acuity,manifest refraction,and visual quality metrics.According to their subjective symptoms patient were divided in two groups:satisfied and unsatisfied.Results:Uncorrected intermediate(0.15±0.11 vs 0.18±0.01,P=0.04)and near(0.26±0.12 vs 0.31±0.11,P=0.04)(UIVA,UNVA)log MAR visual acuity was significantly better,cylindrical error less(0.31±0.36 vs 0.67±0.29,P=0.05),axial length(AL)smaller(23.68±1.3 vs 24.22±1.6,P=0.05),Strehl ratio higher(0.08±0.08 vs 0.05±0.04,P=0.03)and mesopic pupil larger(4.3±1.1 vs 3.7±1.05,P=0.01)among satisfied patients.Residual cylinder,Strehl ratio,halos,mesopic pupil diameter and UNVA were significant predictors of patient satisfaction.Uncorrected distance visual acuity,higher order Strehl ratio and pupil diameter were significant predictors of halos.Near visual acuity significantly correlated(P=0.018,R=0.22)with axial length.Conclusions:Uncorrected cylindrical error,poor reading quality,larger pupil and halos seem to be the most disturbing factors for patients implanted with the Tecnis Symfony IOL.