Diseases of the lacrimal apparatus

The lacrimal apparatus consists of the lacrimal gland, which secretes the aqueous layer of the tear film, the lacrimal sac, into which the tears drain, and the nasolacrimal duct, through which the tears drain into the nose. Inflammation of the lacrimal gland is called dacryoadenitis and is commonly caused by viral or bacterial infections. The condition typically presents with conjunctival hyperemia, S-shaped ptosis, mucopurulent discharge, and discomfort. Dacryostenosis refers to the congenital or acquired obstruction of the nasolacrimal duct (NLD) and presents with excessive tearing. NLD obstruction can cause stasis of tears in the lacrimal sac, which predisposes to secondary bacterial infection of the sac, known as dacryocystitis. The diagnosis is usually clinical, and may be supported by bacterial cultures, imaging (CT, x-ray), and probing of the nasolacrimal duct. Treatment is often conservative (e.g., NSAIDs, warm compresses), but may also require antibiotics in cases of bacterial infections or invasive procedures to remove obstructions (e.g., NLD dilation).

References:^{[1][2][3][4][5][6]}

Congenital dacryostenosis

• Definition: nasolacrimal duct (NLD) atresia/obstruction in an infant caused by a developmental anomaly and characterized by epiphora (excessive tearing)
• Incidence: up to 6% of live births (common condition)
• Clinical features
  • Epiphora within 2–4 weeks of birth
  • Palpation of the lacrimal sac may cause tears to leak from the lacrimal punctum.
• Diagnostics: clinical diagnosis
  • Syringing or probing of the duct to determine the site of obstruction and remove the obstruction, if necessary
  • Lacrimal syringing: reflux of saline irrigated into the lacrimal punctum indicates NLD obstruction
  • Lacrimal duct probing
    • To determine the site of the obstruction and recanalize the duct; a diagnostic and therapeutic procedure
    • Indicated in infants with persistent epiphora despite lacrimal duct massage (see below)
    • The lacrimal punctum is dilated and a flexible metallic probe is inserted into the NLD. If the probe encounters an obstruction, this confirms the diagnosis.
    • Light pressure on the probe breaks through any obstruction and recanalizes the NLD.
    • Presence of ocular infection is a contraindication to probing.
• Treatment:
  • Lacrimal sac massage
  • Dilation or stenting of the duct
  • Dacryocystorhinostomy (DCR): if other measures fail
    • A surgical procedure in which a direct connection is created between the lacrimal sac and the nose to allow for unimpeded drainage of tears.
    • Can be performed either through a skin incision or endoscopically through the nose.
• Complications (of untreated dacryostenosis): acute/chronic dacryocystitis

Acquired dacryostenosis

• Etiology
  • Concretions in the NLD
  • Granulomatous diseases: sarcoidosis; granulomatosis with polyangiitis, tuberculosis
  • Punctal stenosis: due to chronic conjunctivitis, reaction to eye drops
  • Post-traumatic stenosis (nasal fracture/surgery)
• Clinical features, diagnostics, and complications are similar to those of congenital dacryostenosis.
• Treatment
  • Treatment of the underlying disorder
  • Lacrimal duct probing/intubation: in all patients
  • DCR: in refractory cases

References:^{[2][7][8][9][10][11][12]}

The lacrimal gland should not be probed during acute infection, since this may cause bacteria to spread to other locations.

References:^{[2][10][13][14][15]}

• Etiology
  • Benign tumors: pleomorphic adenoma
  • Malignant tumors
    • Adenocystic carcinoma
    • Mucoepidermoid carcinoma
  • Inflammatory tumors (pseudotumor/inflammatory dacryoadenitis): idiopathic inflammation of the lacrimal gland
• Clinical features
  • Age
    • Benign tumors manifest between 20–40 years of age
    • Malignant tumors manifest > 40 years of age
  • Unilateral swelling of the lateral orbit
  • Unilateral proptosis: painless in benign tumors and painful in malignant tumors
  • Restricted eye movement and diplopia
• Diagnostics
  • CT and/or MRI scan
    • Benign tumors: well encapsulated, no bony destruction
    • Malignant tumors
      • Poorly defined lesions with areas of calcification
      • Destruction of adjacent bones and perineural invasion
    • Pseudotumor: diffusely enlarged lacrimal gland and inflamed surrounding tissue
  • Biopsy of the lacrimal gland
• Treatment
  • Benign tumor: complete removal of the lacrimal gland
  • Malignant tumor
    • Complete removal of the gland in early disease
    • Enucleation of the eye and radiotherapy in advanced disease
  • Pseudotumor: steroids and radiotherapy

References:^[2][16][17]