Nasolacrimal Duct Obstruction
Why does excessive tearing occur?
Tears are produced by the main and accessory lacrimal glands, evenly distributed over the eye surface through the blinking reflex, and drained via the lacrimal drainage system. Excessive production or impaired clearance of tears leads to tearing (epiphora). Causes of excessive tear production include environmental irritants, allergens, eye and eyelid infections, and surface eye diseases. Impaired tear clearance can result from anatomical abnormalities of the eyelids, obstruction of the lacrimal drainage system, or functional disorders. These conditions can occur congenitally or later in life.
How is excessive tearing treated?
When a patient presents with complaints of excessive tearing, it is crucial to inquire about the patient's age, duration of symptoms, and any existing medical conditions. A detailed eye examination, evaluation of the tear ducts, and assessment of the nasal passages are performed to first determine the underlying cause. Subsequently, treatment is planned based on the identified cause, which may involve medication or surgical intervention.
What is lacrimal duct obstruction? What are its symptoms?
Following the completion of tear circulation, the lacrimal drainage system, including the lacrimal canaliculi and sac, facilitates the drainage of tears into the nasal cavity and subsequently into the throat. Any level of blockage within this system disrupts the drainage of tears. The most common complaint in such cases is persistent excessive tearing. Excessive tearing can lead to blurred vision due to constant exposure to tears on the skin surrounding the eyes, which can cause irritation.
Blockage within the system can lead to microbial proliferation and subsequent infection, characterized by heavy crusting, eye redness, and eyelid swelling in the patient. Accumulation within the tear sac may increase, and with pressure between the eye and nose, infected contents from the sac can discharge toward the eye. This area may exhibit painful, inflamed, soft, or hard lumps, and in advanced cases, may rupture through the skin.
Treatment of Lacrimal Duct Obstruction in Infants and Children
In newborns, an incomplete membrane opening where the tear duct meets the nose can lead to persistent tearing starting in the first months after birth. Severe cases may present with swelling and redness at the base of the nose where the tear sac is located, and pressure on the nose can cause discharge into the eye. Diagnosis is confirmed through a detailed eye examination by an oculoplastic surgeon. In congenital lacrimal duct obstruction, massage of the tear sac during the first year is the initial and primary treatment. In cases complicated by infection, antibiotic eye drops may be added to the treatment regimen. Proper technique is crucial for effective massage, and therefore, the massage technique should be demonstrated in detail by an oculoplastic surgeon. With appropriate massage technique, tearing improves in approximately 90% of cases. For cases unresponsive to massage, treatment options include probing, silicone tube intubation, or lacrimal duct surgery based on the patient's age and clinical findings.
Treatment of Lacrimal Duct Obstruction in Adults
In adults, the sole treatment for lacrimal duct obstruction is surgery. Surgical technique is determined based on the level of obstruction. Most commonly, dacryocystorhinostomy (DCR) is performed, creating a new drainage pathway from the tear sac to the nasal cavity, typically at the site where the duct opens into the nose. DCR can be performed through a skin incision or endoscopically through the nasal passage. Success rates for DCR are reported as 95-99% with external incision and 80-95% with endoscopic techniques. Placement of a silicone tube into the duct can enhance surgical outcomes and is easily removable in an office setting after 1-2 months. Different techniques are preferred for more advanced obstructions.