TrueTear review: Managing dry eye disease

On being told that they have dry eye disease, many a patient jokes that they will need to cry more. Management, however, typically involves topical supplementation and sometimes reducing drainage by plugging to increase the tear volume.

The neural control of tear production involves the trigeminal (fifth) cranial nerve. External stimuli on the ocular surface, such as lid activity and atmospheric influence, trigger impulses in afferent fibres in the ophthalmic branch (V1) of the trigeminal.

These pass to the pons in the midbrain where processing occurs to then send signals via both sympathetic and parasympathetic fibres to the sphenopalatine ganglion and then via ophthalmic nerve branches to the lacrimal gland, meibomian glands and goblet cells to produce tears.