目的:使用运动跟踪(MT)布里渊显微镜表征亚临床圆锥角膜(SKC)的局灶性生物力学改变,并评估MT布里渊指标区分SKC眼与正常对照组的能力。
方法:前瞻性横断面研究参与者:对30例患者的30只眼进行了评估,包括15例双侧正常患者的15只眼和15例患者的15只眼SKC。
方法:所有患者均使用定制设备进行Scheimpflug断层扫描和MT布里渊显微镜成像。产生前平台区域(高原)和前150微米(A150)内的平均和最小(Min)MT布里渊值。评估的Scheimpflug指标包括劣等(IS)值,KMax,最薄角膜厚度(TCT),不对称指数,BAD-D,艺术max为评估的所有Scheimpflug和MT布里渊指标生成接收器工作特征(ROC)曲线,以确定曲线下面积(AUROC),灵敏度,和每个变量的特异性。
方法:基于AUROC的判别性能,灵敏度,和特异性。
结果:各组之间的年龄没有显着差异,性别,明显折射球面等效折射(MRSE),远距矫正视力CDVA,KMax,或KISA%索引。在Scheimpflug指标中,TCT组间存在显著差异(556μmvs.522μm,p<0.001),IS值(0.29Dv=1.05D,p<0.001),IVA(0.10对0.19,p<0.001)和KI(1.01对1.05,p<0.001),对于任何其他Scheimpflug度量没有显著差异。在MT布里渊指标中,对于平均高原,对照组和SKC眼睛之间存在明显差异(5.71GHz与5.68GHz,p<0.0001),最小高原(5.69GHz与5.65GHz,p<0.0001),平均A150(5.72GHz与5.68GHz,p<0.0001)和MinA150(5.70GHzvs.5.65GHz,p<0.001)。所有MT布里渊高原和A150均值和最小值指标全分化组(AUROC=1.0),而表现最好的Scheimpflug指标是圆锥角膜指数(AUROC=0.91),IS值(AUROC=0.89),和垂直不对称指数(IVA,AUROC=0.88)。
结论:MT布里渊显微镜指标有效地表征了SKC眼的局灶性角膜生物力学改变,并将这些眼与对照组明显区分开来。包括使用Scheimpflug指标不能准确区分的眼睛。
OBJECTIVE: To characterize focal biomechanical alterations in subclinical keratoconus (SKC) using motion-tracking (MT) Brillouin microscopy and evaluate the ability of MT Brillouin metrics to differentiate eyes with SKC from normal control eyes.
METHODS: Prospective cross-sectional study.
METHODS: Thirty eyes from 30 patients were evaluated, including 15 eyes from 15 bilaterally normal patients and 15 eyes with SKC from 15 patients.
METHODS: All patients underwent Scheimpflug tomography and MT Brillouin microscopy using a custom-built device. Mean and minimum MT Brillouin values within the anterior plateau region and anterior 150 μm were generated. Scheimpflug metrics evaluated included inferior-superior (IS) value, maximum keratometry (Kmax), thinnest corneal thickness, asymmetry indices, Belin/Ambrosio display total deviation, and Ambrosio relational thickness. Receiver operating characteristic (ROC) curves were generated for all Scheimpflug and MT Brillouin metrics evaluated to determine the area under the ROC curve (AUC), sensitivity, and specificity for each variable.
METHODS: Discriminative performance based on AUC, sensitivity, and specificity.
RESULTS: No significant differences were found between groups for age, sex, manifest refraction spherical equivalent, corrected distance visual acuity, Kmax, or KISA% index. Among Scheimpflug metrics, significant differences were found between groups for thinnest corneal thickness (556 μm vs. 522 μm; P < 0.001), IS value (0.29 diopter [D] vs. 1.05 D; P < 0.001), index of vertical asymmetry (IVA; 0.10 vs. 0.19; P < 0.001), and keratoconus index (1.01 vs. 1.05; P < 0.001), and no significant differences were found for any other Scheimpflug metric. Among MT Brillouin metrics, clear differences were found between control eyes and eyes with SKC for mean plateau (5.71 GHz vs. 5.68 GHz; P < 0.0001), minimum plateau (5.69 GHz vs. 5.65 GHz; P < 0.0001), mean anterior 150 μm (5.72 GHz vs. 5.68 GHz; P < 0.0001), and minimum anterior 150 μm (5.70 GHz vs. 5.66 GHz; P < 0.001). All MT Brillouin plateau and anterior 150 μm mean and minimum metrics fully differentiated groups (AUC, 1.0 for each), whereas the best performing Scheimpflug metrics were keratoconus index (AUC, 0.91), IS value (AUC, 0.89), and IVA (AUC, 0.88).
CONCLUSIONS: Motion-tracking Brillouin microscopy metrics effectively characterize focal corneal biomechanical alterations in eyes with SKC and clearly differentiated these eyes from control eyes, including eyes that were not differentiated accurately using Scheimpflug metrics.
BACKGROUND: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.