LASIK术后眼前节形态变化及相关影响因素分析

背景 准分子激光角膜原位磨镶术(LASIK)是矫正屈光不正的主要方式之一,术中角膜基质层切削、负压吸引等操作可能导致术后眼前节形态和结构的改变,这些改变对术眼会带来何种影响值得关注. 目的 探讨LASIK对眼前节形态变化的影响,并分析其原因. 方法 采用等距抽样方法选择2012年5月至2013年7月于重庆明达眼科接受LASIK患者31例59眼的临床资料进行回顾性分析,患者平均年龄为(24.52±8.41)岁,术眼平均等效球镜度为(-5.96±3.75)D.分别于LASIK术前及术后1、3、6个月采用Sirius眼前节分析仪测量前房角(ACA)、前房容积(ACV)、中央前房深度(ACD)等参数,采用A型超声测量晶状体厚度(LT).以角膜4 mm半径平面为界限将前房分为前、后2段,计算矢高段前房深度(Sag4mmACD)(即角膜后表面顶点至角膜4 mm半径平面高度)和残余前房深度(RACD)(即角膜4 mm半径平面至晶状体前表面高度).采用Pearson相关分析法评估ACD与RACD和LT之间的相关性.结果 术眼术前及术后1、3、6个月ACA、ACV、ACD、RACD和LT测量值的总体比较差异均有统计学意义(F=8.319,P＜0.05;F=11.596,P＜0.05;F=24.045,P＜0.01;F=16.087,P＜0.05;F=15.333,P＜0.01),术眼术后1～6个月ACA、ACV、ACD、RACD测量值较术前均明显减小,差异均有统计学意义(均P＜0.05),而Sag4mmACD值与术前比较差异无统计学意义(P＞0.05);术眼术后各时间点LT值较术前均明显增加,差异均有统计学意义(均P＜0.01).术前及术后1、3、6个月ACD与RACD均呈显著正相关(r=0.976、0.824、0.724、0.938,均P＜0.01);术后3个月和6个月术眼LT值与ACD值均呈明显负相关(r=-0.344,P＜0.01;r=-0.363,P＜0.01). 结论 近视眼LASIK术后ACD变浅,ACD变化区域主要为角膜4 mm半径平面至晶状体前表面,该变化可能与术后视近时调节力增强致LT增加使晶状体前表面前移有关.     

Cirrus HD-OCT与HRT2测量近视眼视盘参数的一致性评估

背景 近视是常见的眼病且是原发性开角型青光眼的风险因素.近视眼视盘参数的准确测量在临床工作中具有重要意义. 目的 比较频域光学相干断层扫描仪(Cirrus HD-OCT)和海德堡激光共焦断层扫描仪(HRT2)测量近视眼视盘参数的一致性,并探讨近视患者眼轴长度(AL)与2种仪器测量差值的关系.方法 采用横断面研究设计,纳入2010年9-12月在汕头大学·香港中文大学联合汕头国际眼科中心就诊的单纯近视患者150例,每例患者任意选择一眼纳入分析.受检眼均接受眼部检查,包括裸眼视力(UCVA)、最佳矫正视力(BCVA)、裂隙灯显微镜、视野检查和眼底检查.根据等效球镜度(SE)将受检眼分为低度近视组(SE≤-3.00 D)、中度近视组(-3.00 D＜SE＜-6.00 D)和高度近视组(SE≥-6.00D),分别为35、60和55眼.分别采用IOLMaster、Cirrus HD-OCT和HRT2测量受检眼AL和视盘参数,后者包括视盘面积、盘沿面积、视杯容积、杯盘面积比(ACDR)和垂直杯盘比(VCDR),对Cirrus HD-OCT测量的视盘参数进行光学放大效应校正,比较HRT2和校正后的Cirrus HD-OCT视盘参数测量值的一致性;分析AL与2种仪器视盘参数测量差值之间的关系.结果 受检者平均屈光度为(-5.22±2.34)D,平均AL为(25.62±1.10)mm.经光学放大效应矫正后的Cirrus HD-OCT视盘参数值均大于校正前的测量值,差异均有统计学意义(均P＜0.001).高度近视组受检眼经Cirrus HD-OCT测量的视盘面积值明显大于HRT2的测量值(P＜0.001),中度近视组HRT2测量的盘沿面积大于Cirrus HD-OCT的测量值(P=0.040),低、中、高度近视组Cirrus HD-OCT测量的ACDR、VCDR和视杯容积值均明显大于HRT2的测量值,差异均有统计学意义(均P＜0.001).Cirrus HD-OCT和HRT2测量的视盘面积的95％一致性范围(LoA)为-0.64～ 0.74 mm2,盘沿面积的95％ LoA为-0.74 ～0.62 mm2,均大于0.5;2种仪器测量的视盘面积、盘沿面积、视杯容积的差值与AL均呈微弱正相关(r=0.158、0.148、0.156,均P＜0.05);2种仪器测量的ACDR和VCDR差值与AL间均无明显相关性(r=0.012、0.093,均P＞0.05).结论 Cirrus HD-OCT测量近视眼视盘参数受光学放大效应的影响,眼轴越长,光学放大效应越明显.Cirrus HD-OCT与HRT2测量的视盘参数一致性较差,临床上2种检测结果不能相互替代,2种仪器测量的差异随着眼轴的增长而变大.     

Ophtha TOP测量角膜屈光参数的稳定性及其与Pentacam测量的一致性评估

背景 角膜屈光参数的准确测量对于眼表疾病的诊治、屈光手术的设计、人工晶状体屈光度的计算等至关重要,Ophtha TOP是一种用于临床的新型角膜人工晶状体测量仪,但验证其测量角膜屈光参数稳定性及准确性的研究尚少见. 目的 评估Ophtha TOP测量正常人群角膜屈光参数的稳定性,并评价白内障术前患者用Ophtha TOP测量的角膜屈光参数与Pentacam测量结果的一致性. 方法 采用诊断试验可靠性评价方法,2013年9月至2014年10月在天津市眼科医院选取健康志愿者30人60眼行Ophtha TOP检查,评价Ophtha TOP测量角膜屈光参数的稳定性;另选取拟行白内障手术的白内障患者30例30眼进行OphthaTOP检查,以评估Ophtha TOP测量角膜屈光参数与Pentacam测量结果的一致性.记录角膜曲率最平坦曲率径线(Kf)、最陡峭曲率径线(Ks)、平均角膜曲率(Km),并记录轴位J0和J45的散光度.正常眼使用OphthaTOP连续测量5次以上,采用组内相关系数(ICC)、变异系数(CoYs)和重复度(2.77Sw)评价Ophtha TOP测量上述参数的稳定性;白内障患者用Ophtha TOP和Pentacam连续测量2次以上,采用Bland-Altman一致性分析法评估Ophtha TOP测量的角膜屈光参数和散光参数与Pentacam测量结果的一致性. 结果 Ophtha TOP测量的正常眼Kf、Ks、Km、J0和J45的ICC均≥0.90,重复度2.77Sw均≤0.36,Kf、Ks、Km的CoVs均≤0.30.Ophtha TOP与Pentacam测量的白内障眼的角膜屈光参数Kf、Ks和Km的平均差值分别为(0.18±0.28)、(0.24±0.29)和(0.21±0.26)D,Ophtha TOP测量值均略高于Pentacam测量值,差异均有统计学意义(t=3.48、4.50、4.49,均P=0.00);而2种测量仪器测量的散光参数J0、J45的平均差值分别为(0.07±0.21)D和(-0.02±0.18)D,差异均无统计学意义(均P＞0.05).Bland-Altman一致性检验显示,2种测定方法测量的Kf、Ks和Km的95％一致性区间(LoA)分别为-0.37 ～0.73、-0.33～0.81和-0.30 ～0.72 D,J0和J45的95％LoA分别为-0.34～0.48和-0.37～0.33D. 结论 Ophtha TOP对正常人眼角膜屈光参数测量结果的稳定性较好.在白内障术前患者中,Ophtha TOP测量的角膜曲率和角膜散光结果与Pentacam测量值一致性好.     

Comparison of plain with pH-adjusted bupivacaine with hyaluronidase for peribulbar block

Fifty patients scheduled for cataract surgery under peribulbar block were randomised to receive either plain (pH 5.4) or pH-adjusted (pH 6.8 range 6.7-6.9) 0.75% bupivacaine. Hyaluronidase was added to both solutions prior to peribulbar block. The time of onset of akinesia of the globe and the need for supplementary injections were recorded by an independent observer. Patients who returned for surgery to the second eye received the alternative local anaesthetic solution for the second peribulbar block. The relative efficacy of the different anaesthetic solutions was compared in patients who underwent unilateral surgery (Group A, n = 50). In 12 patients (Group B) who underwent bilateral surgery, direct comparisons between eyes in the same patient were possible. In both groups of patients, eyes receiving peribulbar block with the pH-adjusted solution showed a shorter time to partial akinesia of the globe (P less than 0.05). However, there was no difference between the solutions in the time to complete akinesia of the globe, but the number of supplementary injections required for an effective block with the pH-adjusted solution was increased. Onset time to akinesia of the lateral and superior rectus muscles was shortened in patients receiving the pH-adjusted solution but there were minimal effects on the medial and inferior recti.     

计算机技术在眼科教学中的应用

运用计算机技术改进了传统眼科教学模式中的授课与见习,出题考查和成绩管理的方法,提高了眼科的教学质量,达到了教与学的和谐发展。     

运用Keratograph 5M眼表综合分析仪评价干眼患者的泪膜及睑板腺功能

目的使用Keratograph 5M眼表综合分析仪测定干眼患者的泪膜功能,并运用睑板腺照相评分系统评估睑板腺功能。方法选取干眼患者及健康对照组各72只眼,所有检查者均先后完成以下检查：眼表疾病指数（OSDI）问卷评估眼部症状;Keratograph 5M测量下睑中央泪河高度（TMH）、非侵袭泪膜破裂时间（NIBUT）包括首次NIBUT和平均NIBUT、上下睑板腺红外线照相评分;传统荧光素钠染色方法测量荧光素钠泪膜破裂时间（FBUT）。结果干眼组OSDI问卷评分高于健康对照组,而TMH、首次NIBUT、平均NIBUT值均低于健康对照组,差异均有统计学意义（均 P < 0.01）。干眼组的睑板腺照相评分总分高于健康对照组,差异均有统计学意义（均 P < 0.01）;上下睑总分与首次NIBUT、平均NIBUT显著相关（ r=-0.449、-0.398,均 P < 0.01）,与年龄无相关性（ r=0.031, P>0.05）。首次NIBUT、平均NIBUT与FBUT均显著相关（ r=0.833、0.727,均 P < 0.01）。 结论使用Keratograph 5M眼表综合分析仪能简便、准确、非侵袭性地评价干眼患者的泪膜及睑板腺功能;睑板腺照相评分系统能较全面、客观、简便地评价睑板腺功能。     

Reproducibility of RTVue retinal nerve fiber layer thickness and optic nerve head measurements in normal and glaucoma eyes

Background RTVue spectral-domain optical coherence tomography （OCT） is a new, ultra high-speed and high-resolution instrument, potentially to measure the presence of glaucoma or its progression accurately. The objective of this study was to evaluate its reproducibility of retinal nerve fiber layer （RNFL） thickness and optic nerve head （ONH） measurements in normal and glaucoma eyes. Methods This study was an observational clinical study. One eye was selected randomly from each of 89 normal individuals and 63 glaucoma patients in a range of severity. RNFL thickness and ONH were measured 3 times on the same day to determine intrasession variability. The same instrument was used by the same operator for all scans. Intrasession within-subject standard deviation （Sw）, precision （1.96xSw）, coefficient of variation （CVw, 100xSw/overall mean）, and intraclass coefficient （ICC） were calculated to evaluate reproducibility. Results RTVue OCT demonstrated double hump patterns in the RNFL profiles. High reproducibility was observed in all ONH parameters. For normal eyes, the value of ICC ranged between 0.98 and 1.00. For eyes with different extent of glaucoma, it ranged between 0.94 and 1.00. High reproducibility was also observed in RNFL thickness measurements. The values of ICC for averaged RNFL thickness ranged between 0,95 and 1.00 in all cases. For regional parameters, it ranged from 0,94 to 0.98 for normal eyes, 0.94 to 1.00 for mild glaucoma eyes, 0.87 to 1.00 for moderate glaucoma eyes, and 0.77 to 0.97 for severe glaucoma eyes. The nasal regions of severe glaucoma appeared to be most variable, as nasal lower region and inferior nasal region had the ICC values of 0.77 and 0.87. Conclusion Reproducibility of RTVue RNFL and ONH measurements was excellent in normal and glaucoma groups.     

Oxygenation of patients undergoing ophthalmic surgery under local anaesthesia

The oxygenation of 30 patients undergoing elective ophthalmic surgery without sedation whilst breathing air was studied and was compared with two methods of oxygen supplementation. Arterial oxygen saturation, inspired and expired oxygen and carbon dioxide were analysed. The delivery of oxygen at 2 l.min⁻¹ via nasal cannulae was shown to be superior to a method which directed oxygen from under the surgical drapes.