Purpose This study evaluates the predictive power of the critical flicker fusion frequency (CFF) test for visual outcomes in keratoprosthesis (KPro) candidates, comparing its accuracy with B-scan ultrasound, flash visual evoked potentials (fVEP) and endoscopy. Methods The study included 42 patients (42 eyes) scheduled for KPro surgery with a median follow-up period of 6 months. The receiver operating characteristic curve identified the cut-off threshold for CFF in the model development study (17 eyes). All patients in the comparison study (25 eyes) underwent preoperative assessments including trichromatic CFF (red, green and yellow), B-scan ultrasound, fVEP and perioperative endoscopy. Results were classified as either favourable or unfavourable predictors of visual outcomes based on predefined criteria. Sensitivity and specificity of each assessment were calculated based on postoperative best-corrected visual acuity (BCVA)≥20/200. The Bland-Altman test assessed the consistency between CFF-predicted BCVA and actual BCVA. Results Among the trichromatic CFF tests, the yellow-CFF (yCFF) exhibited the highest area under the curve value of 0.97 and a cut-off threshold at 10 Hz for predicting postoperative BCVA≥20/200 (p<0.05). yCFF achieved 90% sensitivity and 80% specificity in predicting satisfactory postoperative outcomes. Endoscopy had 80% sensitivity and 80% specificity, B-scan showed 70% sensitivity and 60% specificity, and fVEP had 75% sensitivity and 40% specificity. yCFF showed a mean bias of 0.091 logarithm of the minimum angle of resolution (logMAR) in postoperative prediction. Conclusions The CFF test provides robust visual function evaluation in KPro candidates. It demonstrates superior predictive accuracy for visual prognosis compared with routine ophthalmologic examinations, such as B-scan ultrasonography, fVEP and endoscopy. All data relevant to the study are included in the article or uploaded as online supplemental information.

中文翻译：

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利用临界闪烁融合频率、B 扫描、视觉电生理学和内窥镜预测人工角膜手术中的视觉结果


目的 本研究评估临界闪烁融合频率 (CFF) 测试对人工角膜 (KPro) 候选者视觉结果的预测能力，并将其与 B 扫描超声、闪光视觉诱发电位 (fVEP) 和内窥镜检查的准确性进行比较。方法 该研究包括 42 名计划接受 KPro 手术的患者（42 只眼睛），中位随访时间为 6 个月。受试者工作特征曲线确定了模型开发研究（17 只眼）中 CFF 的截止阈值。比较研究中的所有患者（25 只眼睛）均接受了术前评估，包括三色 CFF（红、绿、黄）、B 扫描超声、fVEP 和围手术期内窥镜检查。根据预定义的标准，结果被分为有利或不利的视觉结果预测因子。每个评估的敏感性和特异性根据术后最佳矫正视力（BCVA）≥20/200计算。 Bland-Altman 检验评估了 CFF 预测的 BCVA 与实际 BCVA 之间的一致性。结果 在三色 CFF 测试中，黄色 CFF (yCFF) 的曲线下面积值最高，为 0.97，预测术后 BCVA ≥20/200 的截止阈值为 10 Hz（p<0.05）。 yCFF 在预测满意的术后结果方面达到了 90% 的敏感性和 80% 的特异性。内窥镜检查的敏感性为 80%，特异性为 80%，B 扫描的敏感性为 70%，特异性为 60%，fVEP 的敏感性为 75%，特异性为 40%。 yCFF 在术后预测中显示最小分辨率 (logMAR) 的平均偏差为 0.091 对数。结论 CFF 测试为 KPro 候选者提供了可靠的视觉功能评估。 与常规眼科检查（如 B 扫描超声检查、fVEP 和内窥镜检查）相比，它对视觉预后的预测准确性更高。与研究相关的所有数据都包含在文章中或作为在线补充信息上传。