Ayurvedic Concept of Neural Mechanism of the Lacrimal Functional Unit and Its Disruption

The lacrimal functional unit (LFU) is defined as an integrated system comprising the lacrimal glands, ocular surface (cornea, conjunctiva and meibomian glands) and lids, and the sensory and motor nerves that connect them. The majority of dry eye symptoms are due to a chronic inflammation of the lacrimal functional unit resulting in a loss of tear film integrity and normal function. This leads to a reduction in the ability of the ocular surface to respond to environmental challenges. Maintenance of tear film stability is very important for the preservation of ocular surface defense mechanism. It is essential to analyze the Ayurvedic concept of neural mechanism of LFU so that effective management of ocular surface inflammations can be derived. By exploring the Ayurvedic literature, it is evident that Tridoshas play a vital role for the formation and regulation of the lacrimal functional unit which is necessary for the integrity of ocular surface system. In this article an attempt has been made to elaborate the role of Tridoshas in maintaining the proper control of the lacrimal functional unit and how it will cause diseases in conditions of vitiation.