Delicado-Miralles Miguel, Velasco Enrique, Díaz-Tahoces Ariadna, Gallar Juana, Acosta M Carmen, Aracil-Marco Adolfo
Cellular and Systems Neurobiology Unit, Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, San Juan de Alicante, Spain.
The European University of Brain and Technology-NeurotechEU, San Juan de Alicante, Spain.
Front Med (Lausanne). 2021 Oct 26;8:709712. doi: 10.3389/fmed.2021.709712. eCollection 2021.
Perfluorohexyloctane (F6H8) eyedrops have been recently introduced in Europe as a product to treat dry eye disease, based on its ability to reduce tear film instability in Meibomian gland dysfunction and evaporative dry eye disease, although its mechanism of action is still unknown. In the present pilot study, we evaluated the effects of the ocular instillation of a single drop of commercial F6H8 eyedrops in 20 healthy humans (9 women/11 men), measuring: (a) Corneal surface temperature (CST) from infrared video images; (b) tear volume using phenol red threads; (c) blinking frequency; and (d) ocular surface sensations (cold, dryness, pricking, foreign body, burning, itching, gritty, eye fatigue, watering eyes, and light-evoked discomfort sensations; scored using 10 cm Visual Analog Scales), before and 5-60 min after F6H8 or saline treatment. CST decreased and tearing and blinking frequency increased significantly after F6H8 but not after saline solution. When applied unilaterally, CST decreased only in the F6H8-treated eye. No sensations were evoked after F6H8 or saline. The corneal surface temperature reduction produced by topical F6H8 does not evoke conscious ocular sensations but is sufficient to increase the activity of corneal cold thermoreceptors, leading to an increased reflex lacrimation and blinking that may relieve dry eye condition thus reducing ocular discomfort and pain.
全氟己基辛烷（F6H8）眼药水最近在欧洲推出，作为一种治疗干眼症的产品，基于其在睑板腺功能障碍和蒸发型干眼症中减少泪膜不稳定的能力，尽管其作用机制仍不清楚。在本初步研究中，我们评估了向20名健康人（9名女性/11名男性）单眼滴入一滴市售F6H8眼药水的效果，测量：（a）从红外视频图像中获取角膜表面温度（CST）；（b）使用酚红棉线测量泪液量；（c）眨眼频率；以及（d）眼表感觉（冷、干、刺痛、异物感、烧灼感、瘙痒感、磨砂感、眼疲劳、流泪和光诱发不适感；使用10厘米视觉模拟量表评分），在F6H8或生理盐水治疗前以及治疗后5 - 60分钟进行测量。F6H8治疗后CST降低，流泪和眨眼频率显著增加，而生理盐水治疗后则无此现象。单侧应用时，CST仅在F6H8治疗的眼睛中降低。F6H8或生理盐水应用后均未诱发感觉。局部应用F6H8引起的角膜表面温度降低不会诱发有意识的眼表感觉，但足以增加角膜冷感受器的活性，导致反射性流泪和眨眼增加，这可能缓解干眼状况，从而减轻眼部不适和疼痛。
