Tear duct surgery does not give the expected result in every patient, and watering can persist. The most common cause is narrowing of the new passage by scar tissue. In revision, the decisive step is establishing the level of the obstruction and the state of the nose before operating.
Nasolacrimal duct obstruction prevents tears from draining into the nose, causing persistent watering, discharge and recurrent infection. In adults it most often occurs where the duct enters the nose, and complete obstruction is treated surgically by creating a new passage between the lacrimal sac and the nose.
The commonest reason a baby's eye waters is that the thin membrane where the tear duct opens into the nose has not opened after birth. The great majority of these congenital blockages resolve within the first twelve months. Lacrimal sac massage, lid hygiene and regular review carry that period, while pictures such as sac infection are assessed without waiting.
The lacrimal system has two parts. The secretory part consists of the lacrimal gland, which sits in the upper outer corner of the orbit, together with the accessory glands in the lid margin and conjunctiva. The drainage part is the channel system that carries tears from the ocular surface into the nose.
The tear film has three layers: an outer oily layer from the meibomian glands of the lid margin, a middle watery layer, and an inner mucin layer that lets the film adhere to the ocular surface. Every blink renews this film and draws tears into the upper and lower puncta at the inner corner of the eye. From there they pass through the canaliculi, the lacrimal sac and the nasolacrimal duct into the nasal cavity. This is why the nose runs when we cry.
A disorder anywhere along this chain is described as a lacrimal system disorder. Problems on the secretory side cause dryness; problems on the drainage side cause watering.
Watering (epiphora) is one of the complaints I hear most often. Most patients assume the only cause is a blocked duct, but there are two distinct mechanisms.
It may sound contradictory, but dry eye also causes watering. When the surface dries out, a reflex produces dilute, poor-quality tears, and the patient describes both burning and watering. Treatment given without making this distinction does not work. See the dry eye disease and ingrown eyelashes pages for detail.
Dacryocystitis is inflammation of the lacrimal sac, and there is almost always an underlying duct obstruction. Tears stagnating in the sac create a favourable environment for bacterial growth.
Acute dacryocystitis begins abruptly, with a painful, red, warm swelling beside the bridge of the nose, sometimes with fever and malaise. The infection has to be brought under control first. Chronic dacryocystitis is more insidious: persistent watering, morning crusting and discharge that appears when the sac is pressed.
Settling the infection is only a temporary solution; unless the obstruction is relieved, the picture recurs. Definitive treatment is surgical, and it is planned once the acute episode has settled. See adult nasolacrimal duct obstruction.
In the short video below I describe the newborn form of sac distension, the dacryocystocele.
Treatment follows the diagnosis; the same approach is not applied to every kind of watering.
Options are not exhausted in patients whose symptoms persist after earlier surgery. I have set this out on the revisional surgery for failed nasolacrimal duct obstruction treatment page.
Lacrimal system disorders can largely be brought under control with early diagnosis and appropriate treatment. Identifying the true source of the watering is the step that determines everything that follows.
Ayşe Dolar Bilge MD, FEBOphth.
Ophthalmologist, Oculoplastic Surgery
English
