A watery eye is a common complaint, which may be transient or longstanding.
It may be due to one or more factors including: increased tear production due to ocular surface or lid disease; eyelid laxity, which impedes the active process of tear drainage which occurs during blinking, and finally, reduced outflow of tears due to narrowing or blocking of the lacrimal (tear) drainage system.
Treatment is directed towards the cause:
Increased tear production is usually due to reflex tearing in response to a local irritant such as misdirected eyelashes (trichiasis) or eyelid malposition (ectropion or entropion)
Eyelid laxity causes failure of the lacrimal pump, the mechanism by which tears flow across the eye surface and into the tear drainage holes (punctae) in the inner corners of the eyelids. The eyelids are an essential part of the lacrimal pump system so that when they are lax due to ageing changes, trauma, or facial nerve palsy for example, tear drainage is reduced causing tears to spill over onto the face. Treatment may involve restoring correct eyelid position, often by tightening the lower lid (ectropion repair)
Reduced tear drainage may be caused by obstruction at any point along the tear drainage pathway from the puncate (tear drainage holes at the inner aspect of the eyelids), to the canaliculi to the nasolacrimal duct. Surgery is usually required and may involve a punctoplasty for a stenosed or occluded punctum or DCR (dacryocystorhinostomy) for obstructions further along the drainage system.