EyeWorld China December 2018 Issue

2018年12月 EWAP ॖෂ新闻 21 618 Copyright © SLACK Incorporated Corneal Tomography vs New Biomechanical Index/Chan et al combined parameter based on Scheimpflug-based cor- neal tomography and biomechanical assessments. S TATISTICAL A NALYSIS Only one eye with the lower average keratometry was selected for analysis for normal participants. As for pa- tients with subclinical keratoconus, the less severe eye with lower average keratometry value was selected. Statistical analysis was performed using R 3.2.5 soft- ware (R Foundation, Vienna, Austria). Classification analyses between normal and subclinical keratoconus were evaluated using receiver operating characteristic (ROC) curves. The area under the ROC curve (AUC) and partial AUC (pAUC) with specificity of 80% or greater for each classifying parameter was compared based on bootstrap resampling with 200 replicates, one eye from each participant was sampled with re- placement in each bootstrap replicate. AUCs provide an overall comparison of the whole ROC curves with an AUC of 1 representing a perfect classification at any level of specificity. A common classifying system in which AUC 0.5 to 0.6 = fail; 0.6 to 0.7 = poor; 0.7 to 0.8 = fair; 0.8 to 0.9 = good; and 0.9 to 1.0 = excellent is adopted. Although pAUCs focus on the comparison of ROC curves at the sector with specificity of 80% or greater, a pAUC of 0.2 represents a perfect classifica- tion at any level of specificity of 80% or greater. Be- cause a low level of specificity is usually irrelevant to practical use, it is believed that the pAUC is more rele- vant to clinical practice. The mean and median values for each parameter measured for all eyes were estimat- ed. Comparison of median values in each parameter between groups was performed using Mann–Whitney U tests. A P value of less than .05 was considered sta- tistically significant. RESULTS The study included 23 eyes with subclinical kera- toconus and 37 normal eyes. The mean age was 32.4 ± 8.4 years (range: 16 to 53 years) with no difference be- tween groups ( P = .779). Parameters obtained from the Pentacam are shown in Table A (available in the online version of this article). There was no difference in Km, astigmatism, BFS from the anterior and posterior cor- nea, and CKI and KI between normal and SCKC eyes ( P ≥ .097). Significant differences were found in ISV, IVA, CTmin, CTapex, ARTmax, and final D value of BAD between normal and SCKC eyes ( P ≤ .007). Parameters measured with the Corvis ST and the combined TBI are shown in Table A . Significant differences were found in A1T, A1V, DA ratio 1, DA ratio 2, ARTh, RC, IR, Max Inv Rad, SPA1, TBI, and CBI between normal and SCKC eyes ( P ≤ .011). Parameters from the Corvis ST and Pentacam were analyzed for differentiating normal and SCKC eyes. The TBI and BAD final D value demonstrated the high- est AUC (0.925 and 0.786, respectively) and pAUC (0.150 and 0.088, respectively) from the two devices TABLE 1 AUC and pAUC With Specificity ≥ 80% for Classification Between Normal and Subclinical Keratoconus Parameter a AUC pAUC Cut-off Specificity Sensitivity TBI 0.925 0.150 0.16 82.4% 84.4% Corvis ST ARTh 0.836 0.129 444.0 82.4% 81.3% Max inv rad 0.754 0.079 0.19 82.4% 59.4% A1T 0.750 0.052 7.18 82.4% 46.9% RC 0.736 0.094 6.78 82.4% 62.5% Pentacam BAD final D 0.786 0.088 1.38 85.3% 53.1% IVA 0.781 0.125 0.15 88.2% 68.8% ARTmax 0.759 0.095 386.5 82.4% 65.6% CTapex 0.722 0.058 534.5 82.4% 37.5% CTmin 0.710 0.059 529.5 82.4% 43.8% AUC = area under the receiver operating curve; pAUC = partial area under the receiver operating curve; TBI = tomographic biomechanical index; ARTh = hori- zontal Ambrósio’s relational thickness; Max Inv Rad = maximum inverse radius; A1T = time from the initiation of air-puff until the first applanation; RC = radius of curvature at highest concavity; BAD final D = Belin/Ambrósio Enhanced Ectasia Display final D value; IVA = index of vertical asymmetry; ARTmax = maximum Ambrósio’s relational thickness; CTapex = corneal thickness at apex, CTmin = minimum corneal thickness a Only the highest 5 parameters from each device were selected. The Pentacam and the Corvis ST are manufactured by Oculus Optikgeräte, Wetzlar, Germany. ʏ 3. TBI 鉴别正常和 ۈ ࡥռࠦᩕ角膜的 AUC Ҳ较高。 Ď۷：Tommy Chan MD ʏ 4. ؤ ː 1 参数 Ď۷：Usanee Reinprayoon MD Applanation 1 Inward motio 1.79 1.84 1.92 1.6 1.65 1.7 1.75 1.8 1.85 1.9 1.95 2 2.05 Stage1 Stage2 Stage3 A1- Length (mm) 6.89 6.83 6.66 5.8 6 6.2 6.4 6.6 6.8 7 7.2 7.4 Stage1 Stage2 Stage3 A1- Time (ms) 0.14 0.14 0.16 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2 Stage1 Stage2 Stage3 A1- Velocity (m/s) General linear model Applanation 1 Inward moti 1.79 1.84 1.92 1.6 1.65 1.7 1.75 1.8 1.85 1.9 1.95 2 2.05 Stage1 Stage2 Stage3 A1- Length (mm) 6.89 6.83 6.66 5.8 6 6.2 6.4 6.6 6.8 7 7.2 7.4 Stage1 Stage2 Stage3 A1- Time (ms) 0.14 0.14 0.16 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2 Stage1 Stage2 Stage3 A1- Velocity (m/s) General linear model Applanation 1 Inward motion Copyright 2019 ASCRS Ophthalmic Corporation. All rights reserved. The views expressed here do not necessarily reflect those of the editor, editorial board, or publisher, and in no way imply endorsement by EyeWorld, ASCRS, or APACRS. 究分析：(1) 眼轴ԏ量成功的要 ̂—Pentacam 质量ઠ控显示 1K，I1L Master 没有感ൄ号提示；(2) 比较同一Ů眼两种ѳ҄的 Ɓơ重复ԏ量结果，对比眼轴、角膜 ف 率、散光和轴位、前Ӯ深度和ǌː角膜ˢ径 (HWTW) 的重复性； (3) 重复性系数，标准 ו 和ː ߴ Ҳ。 Dr. Hengerer 和同Ƃ发现 Pentacam AXL 的眼轴ԏ量成功率更高，眼轴、角膜 ف 率、散光、轴位和 HWTW 的重复性更 Č，而 IOLMaster ԏ量 ACD 的重复性更Č。 5oNNZ $han, MD ，分享了 2 Sponsored by Alcon Corvis ST (OCULUS) 的应用，他的ʚ目是 “ 断 ڝ ై෗ԓ合生物 ƺ学ԏ量在ା光术前ᒖз中的应用。 ” ණʽ Scheimp뽀ug ʏɏ能够为早期角膜จ˚改变的ႊ断提供有用信ʜ，这些信ʜ是基于断 ڝ 地形ʏ的数֪。他形ճ地将角膜 จ˚؆为“ဘ̀”。这是随时都可能 ڞ 发的角膜ା光术后最严重的 ˄发症。虽然当前的方法ŉ̗Ͳď能鉴别角膜จ˚和正常眼，但 ۈ ࡥռ 疾病的鉴别π常 ܒ ȧ，例如ࠢཊ 性ࠦᩕ角膜和正常眼。 “ פ 了断 ڝ 地形ʏ，我们Џ ʬ评ଦ角膜的生物ƺ学特性，以此更全面了解角膜的特征。特别是因为角膜生物ƺ学的下降是ࠦ ᩕ角膜发生的基础。”Dr. Chan 说。Corvis ST 能够提供这个信 ʜ。 Corvis ST 是一Ѓɸ高ю Scheimpflug ѳ҄，Ѹު角膜受到ǯ ؤ ໢ ڮ 后的形变过ԙ，ై෗ ю度为 4,330 ḃ / ，ځ Ѹުǌː径达 8mm 。 Dr. Chan ؜论了一系ԉনз 参数，介绍了 Vinciguerra 筛查报告，其中包含 7 个重要参数，如DA 比、综合半径、Ambrosio 相关厚度 (ART)、新硬度参数 (SP-A1) 和 Corvis 生物力学指数 (CBI)。 Vinciguerra 利用 CBI 鉴别 ࠦᩕ角膜和正常眼，其 AUC Ҳ 高达 0.990。Dr. Chan 和同Ƃ 研究发现，使用 CBI 鉴别ࠦᩕ角膜和正常角膜的 AUC 为 0.971 。CBI (AUC=0.785) 和 BAD (AUC=0.757) (p=0.590) 鉴别ࠢ ཊࠦᩕ角膜的敏感性分别为 65 和 53 ，特异性为 80 。 Dr. Chan 认为ԓ合断 ڝ 地形ʏ和角膜生物ƺ学特性ԏ量，可以更Č地发现 ۈ ࡥռ或ࠢཊࠦ ᩕ角膜。 OCULUS 将二者结合引入一个新参数：断层地形联合生物力学指数 (TBI)。新的软件应用 Corvis 参数和断层地形数据，最后生成 TBI。 Dr. Chan 和同事分析了 41 例圆锥角膜病例、37 例对照和 23 例亚临床圆锥角膜数据。他们发现，使用 TBI 鉴别正常和亚临床圆锥角膜，AUC 值高达 0.925，特异性为 82.4%，敏感性为 84.4%。 “ ԓ合角膜断 ڝ 地形和生物ƺ 学特性，可以提高手术的安全性和有效性 ”Dr. Chan 说。 6Tanee ReinpraZoon, MD ，分享了她使用 Corvis ST 的经验， ʚ目为 “ 角膜疾病患者角膜生物 ƺ学的ࡥռ应用。 ” Dr. Reinprayoon 介绍了她的ખЯᅣ ：ߑ 如果你ƈ ۈ ࡥռ ࠦᩕ角膜患者做ା光手术，患者可能会出现角膜จ˚。同样，如果是 Fuchs 角膜内皮 ؽ 养不良 (FECD) 做Ƀ内ච手术，患者可能会出现角膜失代ခ。 FECD 是一种进Ǆ性角膜内皮细胞丢失，可以导致 ٲ Մ或๷֍ 的角膜增য和ǌఏ。需要进Ǆࡥ ռনз，角膜内皮镜ّՄ于小的中 ೚区域，细胞计数变异大，角膜য 度౯可以ǎ接ԏ量评ଦ内皮细胞功能。 FECD 组࢚ǌ化的增加对于角膜ࢫ度和生物ƺ学特性有什么影响？ Dr. Reinprayoon 说，角膜生物ƺ学特性有助于理解 FECD 的自然病ԙ，病理和预后。她和同Ƃ采用 Corvis ST 分析了 80 例 FECD 患者的角膜生物ƺ学特性，观察不同的参数。在向内 ̬动೛ь ( ؤ ː 1) ，他们观察了 A1- 时ǎ，角膜达到第一ơ ؤ ː的时ǎ； A1- 长度，第一ơ ؤ ː时 ؤ ː部位长度；和最大፼ౢ点 (HC) ， HC 时ǎ，角膜达到 HC 的时 ǎ；峰Ҳ ࡎ ͼ，峰Ҳǎ ࡎ ͼ； HC ͤ径， HC 时 ف 率ͤ径；变形વ度 (DA) ح， ˨状态的形变量。最后，向外̬动 ( ؤ ː 2) ，他们观察 A2- 时ǎ，角膜达到第ȕơ ؤ ː的时 ǎ； A2- 长度，第ȕơ ؤ ː时 ؤ ː 部位长度； A2- ю度，第ȕơ ؤ ː 时内̬动ю度。她说几乎所有生物ƺ学参数都和ࡥռ分期相关；和正常人群相比， FECD 患者的角膜更̗Ͳ ƻǯ ؤؤ ː。疾病ɿ严重，角膜ɿ ː。 A1- 时ǎ和 A1- 长度似乎是所分析的参数中最敏感的参数。她认为这对患者治疗方ޯ的制定有ъ助。 Dr. Reinprayoon 说，λĎ角膜生物ƺ学特性可以用于ႊ断其它疾病引起的内皮失代ခ，用于角膜移植术后患者的随ਲ਼，可以预ԏ 角膜疾病，评价角膜移植效果和供体参数。 Sponsored by OCULUS Optikgeräte GmbH