Tear film lipid layer thickness and ocular comfort after meibomian therapy via latent heat with a novel device in normal subjects

Abstract

Aim This study measures changes in tear film lipid layer thickness (LLT) and ocular comfort in normal subjects after 10 min use of a novel device, which delivers meibomian therapy with latent heat. The device is designed to promote the release of meibomian sebum into the tear film by delivering latent heat to the eyelids, thus thickening the lipid layer. Normal lid movements are maintained, facilitating resurfacing of the tear film. Method A prospective, controlled, observer masked, single intervention trial in which 24 normal subjects were randomised into three groups. Group I underwent 10 min treatment with the activated device, Group II used the inactivated device for the same duration of time, and Group III had no intervention. The LLT of each subject was measured with a Keeler Tearscope s prior and subsequent to the 10-min period. Subjective alteration in ocular comfort was also assessed. Results Seven of eight subjects (87.5%) in Group I exhibited an increase in LLT. The mean LLT in this group showed a statistically significant increase (left eyes 1.0 levels, Po0.001, right eyes 0.9 levels, Po0.003) compared to Groups II and III. Six of eight subjects (75%) using the activated device experienced subjective improvement in ocular comfort. Conclusion Meibomian therapy with this device increases LLT in normal individuals. This implies a more stable tear film, reflected in subjective improvement in ocular comfort.

Comparison of the Efficacy of Two Lipid Emulsion Eyedrops in Increasing Tear Film Lipid Layer Thickness

“…Of the 64 patients with a deficient lipid layer in at least one eye, 29.7% (n ϭ 19) were able to increase the lipid layer by more than 15 nm by forceful blinking. Because thickened lipid layers have been associated with improvement in dry eye symptoms, 34,35 this finding illustrates that, in many cases, dry eye symptoms may be ameliorated by proper blinking. From these data, it appears that partial or inadequate blinking may be an important component to the cause of dry eye symptoms.…”

“…30 -32 A stable tear film is also critical to successful contact lens wear because a major cause of contact lens-related dryness is thought to be increased evaporation from the tear film. 33 The lipid layer has also been correlated with dry eye symptoms, 32,34,35 another criterion used to diagnose dry eye. 7 Of the 79 patients in the current study capable of LLT evaluation and having considerable dry eye symptoms, as defined by a score of at least five points on the SPEED questionnaire, 68.4% had thin lipid layers in both eyes and 81.0% had thin lipid layers in at least one eye.…”

Ex vivo heat retention of different eyelid warming masks

“…In addition to eyelid masks, promising new eyelid warming technologies include steam [17,19,34,35], thermal [36][37][38][39] and chemically activated disposable sachets [40]. Aside from the effect on the meibum, warm compresses can also transiently degrade vision from the light pressure of the compress [41].…”

Lipid phase behaviour under steady state conditions

“…2,[33][34][35] Another physiological case where 40 these effects can be relevant is for the liquid film of the cornea. 9 In section 5 and 7, we discussed two different possibilities for formation of oriented multilamellar structures at the air-water interface, either by the use of micelles as transporters of insoluble lipids, or due to the interfacial density gradient that can occur if 45 the lipid solution is exposed to an atmosphere with D 2 O. One area of application of this is the preparation of thin ordered lamellar structures, where also other components can be incorporated.…”

“…This generates non-equilibrium transport processes across the air-water interface, which could in 60 turn give rise to unexpected structural changes. [4][5][6][7][8] Similar conditions exist also in the lipid tear film formed on our eyes, which indeed should act to prevent evaporation and dry eyes 9 .…”