SIGNS AND SYMPTOMS
Epiphora is more of a clinical sign than an absolute diagnosis. This condition constitutes insufficient drainage of the tear film from the eyes.
Be aware of the distinction between chronic and acute epiphora. Chronic epiphora results from long-standing or unremitting disorders, and presents a greater clinical challenge than acute epiphora. The acute variety most often results from irritative ocular conditions such as corneal foreign bodies or allergic conjunctivitis, and usually resolves with treatment of the associated disorder. Patients with chronic epiphora report excessive lacrimation, in some cases to the point of tears actually streaming over the lid margins and down their face.
The symptoms may be exacerbated by environmental factors such as excessive cold, wind, pollen or other airborne particulate matter, sleep deprivation, nearpoint strain, or emotional stress. Regarding the latter, some patients may report that they "cry very easily," or that they are constantly wiping their eyes.
Often, the patient complains of intermittently reduced acuity, owing to excessive tears. Irritation to the lids, and in particular the inner canthus, is common because of the constant wetting of that area as well as the continuous mechanical abrasion of tissues. Punctate epithelial keratopathy is another prevalent finding in patients with epiphora. Lid-globe appositional abnormalities, punctal stenosis and lacrimal sac disorders may also be noted.
PATHOPHYSIOLOGY
Epiphora may result from a variety of conditions, but all can be ascribed to one of four basic categories: lid-globe appositional abnormalities, obstructive lacrimal drainage disorders, ocular surface disorders, and rarely, neurogenic lacrimal hypersecretory disorders.
In conditions that alter the normal proximity of the lacrimal puncta to the ocular surface, outflow of tears is impeded. The most obvious cause is acquired ectropion; other examples include entropion and floppy eyelid syndrome.
Obstructive disorders of the lacrimal system are similar to appositional abnormalities, except that in these conditions there is mechanical impedance of the outflow channel. This may take the form of acquired punctal stenosis, canalicular stenosis or canaliculitis, dacryocystitis or lacrimal sac tumors. Occasionally, a large hordeolum or chalazion may induce punctal or canalicular stenosis.
Ocular surface disorders can in some instances induce excessive and symptomatic reflex tearing. While this is typically not significant enough to constitute true epiphora, it should be considered when patients present with complaints of "excessive tearing." Disorders such as chronic keratoconjunctivitis sicca may induce reflex epiphora, in the absence of any lid or lacrimal abnormalities.
Finally, hypersecretion of tears may be encountered in rare neurogenic disorders. Compressive irritation of the parasympathetic lacrimal fibers or aberrant regeneration of cranial nerve VII after trauma may result in enhanced lacrimation, sometimes referred to as "crocodile tears." Rule out neurogenic complications prior to initiating therapy for a lacrimal outflow problem.
MANAGEMENT
Treatment for epiphora involves alleviating the symptoms and correcting the underlying disorder. For lid-globe appositional abnormalities, such as ectropion, the only cure is to surgically realign the punctum with the globe. In some cases of mild medial laxity with punctal eversion, the lid may be repositioned with local cautery alone. Most often, however, this involves modified resection of the lid tissue, or "horizontal lid shortening procedures."
Obstructive disorders generally require somewhat invasive therapeutic measures as well. Punctal and/or canalicular dilation and irrigation is the most common management for stenosis of the lacrimal system. In cases of chronically flaccid or stenotic puncta, laser punctoplasty or ampullotomy may be used to enlarge the outflow orifice. If the blockade exists more distally within the nasolacrimal system, probing alone may be inadequate to alleviate the problem. In these cases, dacryocystorhinostomy (DCR) is often required; this creates a surgical bypass of the common canaliculus directly into the nasal mucosa. Probing procedures are contraindicated in cases of inflammation, such as chronic dacryocystitis, or suspected neoplasm; implement DCR for these conditions.
When ocular surface disorder is the etiology of chronic epiphora, aim treatment at replenishing the normal basal tear volume and improving the overall quality of the tear film. Use artificial tear preparations, punctal or lacrimal occlusion therapy, moist chamber effects, or a combination of these strategies.
Neurogenic hypersecretory disorders, when suspected, should be referred for evaluation and management by a neurologist.
CLINICAL PEARLS
"Tearing" is a common complaint in most optometric practices. For proper management, differentiate between functional epiphora and occasional, symptomatic lacrimation. True epiphora constitutes a chronic problem warranting intervention, whereas normal tearing does not.
Dilation and irrigation, the most common management strategy for punctal and canalicular obstruction, is a quick and easy in-office procedure that can be performed by an optometrist. It is not a permanent solution, however, and may need to be repeated several times each year to maximize patient comfort and satisfaction. Surgical intervention, when necessary, should be d
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