![]() ĭespite its frequent recommendation by eye care practitioners (ECP), warm compress treatments are poorly standardized. Warm compresses have been shown to reduce dry eyes in patients with MGD by improving symptoms, tear film stability, tear evaporation, tear film lipid layer thickness and decreased meibomian gland orifice obstruction, ,,. Although the exact temperature for warm compress therapy in unknown, temperature of 40 ☌ to 45 ☌ have been advocated. Ocular massage is typically advocated following warm compress therapy to empty the ducts and pierce through the obstructive orifices of the meibomian gland, eventually increasing the lipid layer of the tear film. The therapeutic purpose of the warm compresses, placed on the closed eyelids, is to slowly transfer the heat from the compress, through the eyelid tissues to ultimately reach the inner meibomian glands, in an attempt to melt or soften the stagnant meibum. Īlthough management of MGD is not globally standardized, warm compresses are regarded as a primary therapy,. Patients with MGD, and hence evaporative dry eye, are typically more sensitive to evaporation effects from air currents resulting in decreased tear film stability. Consequently, the meibum accumulates in the gland ducts and the force exerted by a simple blink is insufficient to release it onto the ocular surface, resulting in the underlying tear film being more vulnerable to evaporation. Even if the melting point of the meibum in MGD is below that of body temperature at 37 ☌, rendering the meibum liquid, hyperkeratinization of the terminal duct and orifice of the gland prevents the meibum from being secreted. The resulting meibum in patients with MGD is stagnant and thickened. ![]() Despite this variability, the melting point for meibum in obstructed meibomian glands is reported to be between 32 and 45 ☌. The exact melting point of meibum in those suffering from MGD has yet to be determined, as the chemical composition of the secretions is variable and in turn affects its physical attributes. In patients with MGD, the meibum has an altered chemical structure that increases its melting point compared to the physiological 32 ☌. These glands are squeezed by the action of a normal blink to release the meibum, which is subsequently distributed by the action of the lids onto the ocular surface, to minimize the evaporation of the underlying tear film layers. Each eye possesses approximately 60 meibomian glands (25–40 on the upper eyelid and 20–30 on the lower eyelid), which, under normal circumstances, should secrete a clear, liquid oil, called meibum. ![]() It is estimated that the prevalence of MGD is 38.9%, increasing with age. The most common cause of evaporative dry eye appears to be meibomian gland dysfunction (MGD).
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