de Paiva Cintia Sade, Lindsey Jennifer Luiz, Pflugfelder Stephen C
Ocular Surface Center, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA.
Ophthalmology. 2003 Jun;110(6):1102-9. doi: 10.1016/s0161-6420(03)00245-8.
To determine the correlation between the regularity indices of the Tomey TMS-2N computerized videokeratoscopy (CVK) instrument (Tomey, Waltham, MA) with conventional measures of dry eye symptoms and disease.
A retrospective, clinic-based, case-control study.
A total of 16 eyes of 16 asymptomatic normal subjects and 74 eyes of 74 patients with reports of ocular irritation.
Corneal surface regularity and potential visual acuity indices of the Tomey TMS-2N CVK instrument were evaluated in patients with ocular irritation symptoms and in normal subjects.
The surface regularity index (SRI), surface asymmetry index (SAI), potential visual acuity index (PVA), and irregular astigmatism index (IAI) of the Tomey TMS-2N were compared between normal and dry-eye patients. Severity of dry-eye symptoms was assessed with a validated questionnaire. Schirmer 1 test (without anesthesia), biomicroscopic meibomian gland evaluation with a composite severity score (MGD score), fluorescein tear break-up time (TBUT), and corneal fluorescein staining were performed. The correlations between CVK indices of the Tomey TMS-2N and the symptom severity score, Schirmer 1 test, MGD score, TBUT, and corneal fluorescein staining score were studied.
Dry-eye patients had greater mean symptom severity scores, lower Schirmer 1 test scores, greater MGD scores, more rapid TBUT, and greater total corneal fluorescein staining scores (P < 0.001 for all parameters). The SRI, SAI, and IAI were all significantly greater in dry-eye patients than normal subjects. These were 0.46 +/- 0.36 (normal) versus 1.09 +/- 0.76 (dry) for the SRI (P = 0.0017), 0.30 +/- 0.15 (normal) versus 0.90 +/- 1.09 (dry) for the SAI (P = 0.0321), and 0.42 +/- 0.28 (normal) versus 0.56 +/- 0.24 (dry) for the IAI (P = 0.0321). The PVA index was significantly lower in the dry-eye patients (0.89 +/- 0.13) than normal eyes (0.68 +/- 0.23; P = 0.0008). The SRI, SAI, and IAI were positively correlated with total and central corneal fluorescein staining scores (P < 0.00001 for all indices). An SRI (> or =0.80), SAI (> or =0.50), and IAI (> or =0.50) had sensitivities in predicting total corneal fluorescein staining (score > or = 3) of 89%, 69%, and 82%, respectively. The specificity of these indices was 80%, 78%, and 82%, respectively. In all 90 eyes, the mean SRI was greater in subjects older than 50 years (P = 0.012) compared with younger patients, whereas no age effect was noted in the dry-eye patients. The SRI and PVA index showed better correlation with symptoms of blurred vision than the best-corrected visual acuity.
Patients with ocular irritation have an irregular corneal surface that may contribute to their irritation and visual symptoms. Because of their high sensitivity and specificity, the regularity indices of the Tomey TMS-2N have the potential to be used as objective diagnostic indices for dry eye, as well as a means to evaluate the severity of this disease.
确定拓普康TMS - 2N电脑化角膜地形图仪（CVK）（拓普康公司，美国马萨诸塞州沃尔瑟姆）的规则性指数与干眼症状及疾病传统测量指标之间的相关性。
一项基于临床的回顾性病例对照研究。
16名无症状正常受试者的16只眼以及74名有眼部刺激症状报告的患者的74只眼。
对有眼部刺激症状的患者和正常受试者评估拓普康TMS - 2N CVK仪器的角膜表面规则性和潜在视力指数。
比较正常受试者和干眼患者的拓普康TMS - 2N的表面规则性指数（SRI）、表面不对称指数（SAI）、潜在视力指数（PVA）和不规则散光指数（IAI）。使用经过验证的问卷评估干眼症状的严重程度。进行Schirmer 1试验（无麻醉）、用综合严重程度评分（MGD评分）进行生物显微镜下睑板腺评估、荧光素泪膜破裂时间（TBUT）以及角膜荧光素染色。研究拓普康TMS - 2N的CVK指数与症状严重程度评分、Schirmer 1试验、MGD评分、TBUT以及角膜荧光素染色评分之间的相关性。
干眼患者的平均症状严重程度评分更高、Schirmer 1试验评分更低、MGD评分更高、TBUT更快以及角膜荧光素染色总分更高（所有参数P < 0.001）。干眼患者的SRI、SAI和IAI均显著高于正常受试者。SRI分别为0.46±0.36（正常）和1.09±0.76（干眼）（P = 0.0017），SAI分别为0.30±0.15（正常）和0.90±1.09（干眼）（P = 0.0321），IAI分别为0.42±0.28（正常）和0.56±0.24（干眼）（P = 0.0321）。干眼患者的PVA指数（0.89±0.13）显著低于正常眼（(0.68±0.23；P = 0.0008）。SRI、SAI和IAI与角膜荧光素染色总分及中央染色评分呈正相关（所有指数P < 0.00001）。SRI（≥0.80）、SAI（≥0.50）和IAI（≥0.50）预测角膜荧光素染色总分（评分≥3）的敏感度分别为89%、69%和82%。这些指数的特异度分别为80%、78%和82%。在所有90只眼中，50岁以上受试者的平均SRI高于年轻患者（P = 0.012），而干眼患者未观察到年龄效应。SRI和PVA指数与视力模糊症状的相关性优于最佳矫正视力。
有眼部刺激症状的患者角膜表面不规则，这可能导致其刺激症状和视觉症状。由于拓普康TMS - 2N的规则性指数具有高敏感性和特异性，它们有可能用作干眼的客观诊断指标，以及评估该疾病严重程度的一种手段。
