A lacrimal stone, or dacryolith, is a small, hardened deposit that forms within the tear drainage system of the eye. This intricate system collects tears from the eye’s surface and channels them into the nasal cavity. Dacryoliths primarily develop in the lacrimal sac or the nasolacrimal duct, components of this pathway. These formations can impede the normal flow of tears, leading to blockages and discomfort.
Causes of Lacrimal Stones
Lacrimal stones develop from the accumulation and hardening of various cellular and organic materials within the tear drainage system. Debris such as dead epithelial cells, lipids, and mucus can collect, particularly when tear flow is stagnant. Over time, these materials can calcify, forming dacryoliths.
Chronic inflammation or recurrent infections of the tear sac, a condition termed dacryocystitis, contribute to dacryolith formation. These inflammatory processes create an environment conducive to the aggregation and mineralization of debris. Anatomical narrowings within the tear ducts, age-related changes, or even previous eye surgeries can also hinder proper tear drainage, increasing the likelihood of stone development.
Recognizing the Symptoms
The presence of a lacrimal stone manifests through several signs, with excessive tearing, or epiphora, being a common indicator. Tears may constantly overflow onto the cheek because the drainage pathway is obstructed. Individuals might also observe a recurrent discharge from the affected eye, which can appear as mucus or pus. This discharge may lead to crusting along the eyelids, especially upon waking.
Swelling and tenderness near the inner corner of the eye, around the lacrimal sac, are frequent experiences. The skin in this region might appear red and feel warm to the touch. In some instances, if infection or significant swelling occurs, a person’s vision might become temporarily blurred.
Medical Diagnosis and Treatment
Diagnosing a lacrimal stone begins with a physical examination. The doctor may gently press on the tear sac near the inner corner of the eye, a maneuver that can sometimes express mucus or pus, providing material for culture if an infection is suspected. To confirm the presence and location of a dacryolith, imaging studies are employed. A computed tomography (CT) scan can reveal focal areas of high density within the lacrimal sac, sometimes showing a peripheral rim of calcification. A dacryocystogram (DCG), which involves injecting a contrast medium into the tear ducts, can also visualize blockages or filling defects caused by the stone.
Treatment approaches vary based on the stone’s size and the presence of infection. Conservative measures may include applying warm compresses to the affected area and performing gentle massages of the tear sac to encourage drainage. If an infection is present, antibiotic eye drops, such as moxifloxacin or tobramycin, are prescribed for 7-10 days. Oral antibiotics may also be necessary for more extensive infections.
When conservative methods are insufficient, procedural interventions may be considered. Tear duct probing involves inserting a thin, blunt metal wire through the tear duct to physically clear the obstruction. This procedure can be successful in more than 70% of cases but is avoided during acute infections.
For persistent or recurrent blockages, surgical intervention, specifically dacryocystorhinostomy (DCR), is the definitive solution. This procedure creates a new drainage pathway between the lacrimal sac and the nasal cavity, bypassing the obstruction. DCR can be performed externally through a small skin incision near the nose or endoscopically through the nasal passage, with both methods demonstrating high success rates, exceeding 90%.