Bourcier Tristan, Acosta M Carmen, Borderie Vincent, Borrás Fernando, Gallar Juana, Bury Thierry, Laroche Laurent, Belmonte Carlos
Quinze-Vingts National Center of Ophthalmology, University of Paris 6, Paris, France.
Invest Ophthalmol Vis Sci. 2005 Jul;46(7):2341-5. doi: 10.1167/iovs.04-1426.
To explore changes in corneal sensitivity that develop in patients with dry eye and the relationship between sensibility and severity of the dry eye disease.
Experiments were performed in 44 patients with dry eye and 42 healthy individuals. Corneal sensitivity was measured with the Belmonte noncontact gas esthesiometer. Mechanical (air jets at flow rates from 0 to 200 mL/min, reaching the corneal surface at 34 degrees C), thermal (cold or warm air at subthreshold flow rates changing corneal basal temperature +/-1 degrees C), and chemical stimuli (air containing 0% to 50% CO2 at subthreshold flow rate and temperature at the cornea of 34 degrees C) were applied to the center of the cornea to determine the sensitivity threshold for each stimulus modality. The clinical state of the ocular surface was also explored, measuring the fluorescein tear break-up time, the degree of corneal staining with fluorescein and Lissamine green, and tear production with the Schirmer test.
Both in control subjects and patients with dry eye, the corneal thresholds for mechanical, chemical, and thermal stimulation increased with age. Moreover, the thresholds for the three modalities of stimuli were significantly higher in patients with dry eye than in control subjects. In both groups, individual mechanical, chemical, and thermal thresholds correlated significantly. Also, high thresholds in patients with dry eye correlated with the intensity of fluorescein and Lissamine green corneal staining but not with the results of the Schirmer test.
Patients with dry eye exhibit corneal hypoesthesia after mechanical, thermal, and chemical stimulation that appears to be related to damage to the corneal sensory innervation.
探讨干眼症患者角膜敏感性的变化以及敏感性与干眼症严重程度之间的关系。
对44例干眼症患者和42名健康个体进行实验。使用贝尔蒙特非接触式气体感觉计测量角膜敏感性。将机械刺激（流速为0至200 mL/min的气流，在34℃时到达角膜表面）、热刺激（亚阈值流速的冷空气或热空气，使角膜基础温度变化±1℃）和化学刺激（亚阈值流速且角膜温度为34℃时含0%至50%二氧化碳的空气）施加于角膜中央，以确定每种刺激方式的敏感性阈值。还对眼表的临床状态进行了评估，测量荧光素泪膜破裂时间、荧光素和丽丝胺绿角膜染色程度以及用泪液分泌试验测量泪液分泌量。
在对照组和干眼症患者中，机械、化学和热刺激的角膜阈值均随年龄增加。此外，干眼症患者三种刺激方式的阈值显著高于对照组。在两组中，个体的机械、化学和热阈值显著相关。而且，干眼症患者的高阈值与荧光素和丽丝胺绿角膜染色强度相关，但与泪液分泌试验结果无关。
干眼症患者在机械、热和化学刺激后表现出角膜感觉减退，这似乎与角膜感觉神经支配受损有关。
