Chalazion: Etiology, Pathogenesis, Diagnosis and Treatment Methods

A chalazion (translated from the Greek “chálaza”, meaning “small hailstone” or “small lump”) is a chronic, aseptic, lipogranulomatous inflammation caused by the obstruction of the meibomian gland’s outlets. The conditions can affect both the upper and lower eyelids.

Etiology and risk factors

Although the pathophysiology of chalazia is well known, the predisposing factors of this meibomian gland dysfunction are less well known. A chalazion results from obstruction of the meibomian gland duct.

Major provoking factors

The exact underlying cause of this obstruction remains unclear, but a number of key triggers stand out:

• Hormonal changes: puberty and pregnancy.
• Dermatologic and ophthalmologic diseases: rosacea, chronic blepharitis, and seborrheic dermatitis.
• Infections: viral and bacterial.
• General diseases: diabetes mellitus, immunodeficiency, hyperlipidemia, tuberculosis, and leishmaniasis.
• External factors: exposure to air pollutants and poor eyelid hygiene.

The role of hormones and IVF

The meibomian glands are abundantly innervated, and their function is regulated by a complex array of substances, such as androgens, estrogens, progestins, retinoic acid, growth factors, and possibly neurotransmitters. Sex hormone levels are known to affect the structure of the lacrimal and meibomian glands, the conjunctiva, the lateral cells, the cornea, the anterior chamber, the iris, the ciliary body, the lens, the vitreous, and the retina.

Hormone therapy is also a risk factor for meibomian gland dysfunction and dry eye syndrome. Studies suggest that in vitro fertilization (IVF), coupled with powerful hormonal therapy at the stage of embryo implantation and sometimes even throughout the entire pregnancy, also affects the meibomian glands’ functioning.

IVF patients tend to develop meibomian gland dysfunction, meibomitis, styes, and chalazia, which often recur.

Epidemiology

The incidence of chalazion in various medical literature studies varies from 0.2% to 0.7%.

• Gender: some data suggest a higher prevalence in women (due to hormonal influences and cosmetic use), but other studies show no significant difference.
• Age: a chalazion can occur at any age, but it is most common in adolescents and adults under the age of 30. This is due to high levels of androgens, which stimulate the production of skin secretion and increase its viscosity.
• Localization: chalazions are more common on the upper eyelids because more meibomian glands are located there compared to the lower eyelids.

Pathogenesis

Meibomian glands usually produce an oily sebaceous secretion, which is distributed over the surface of the cornea and conjunctiva to keep them moist and prevent the ocular surface from drying.

Mechanism of development:

1. Clogging: the ducts of the meibomian glands become obstructed. Sebaceous secretion accumulates inside the gland with no outlet.
2. Cyst: a cyst gradually grows in the thickness of the eyelid.
3. Inflammation: histopathology shows a lipogranulomatous chronic inflammatory pattern with extracellular fatty deposits surrounded by lipid-laden epithelioid cells, multinucleated giant cells, and lymphocytes.

Clinical presentation and symptoms

When a chalazion develops, patients most often complain about the formation of an elastic mass (“bump”) that creates a cosmetic defect and discomfort.

Main symptoms:

• A dense nodule localized in the thickness of the eyelid;
• Gradual increase in the size of the formation;
• Irritation and swelling of the eyelid;
• Moderate soreness (especially at the beginning of the process, then the pain may go away).

Diagnosis

Diagnosis is made after physical examination. Comprehensive examination: biomicroscopy of the anterior segment, visometry, keratometry, tonometry, and echoscopy.

Picture during visual inspection (slit lamp):

• A nodule in the thickness of the tarsal plate of the eyelid.
• There is an occasional perifocal inflammation associated with it.
• Accumulations of thick secretion can be seen in the aperture of the affected gland.
• Upon palpation, the formation is painless, the skin over it is unchanged, mobile, and not fused with adjacent tissues.
• When turning the eyelid out (examination of the posterior surface), local hyperemia is detected on the conjunctiva in the projection of the chalazion.

Treatment of chalazia

In about a quarter of cases (25%), chalazia go untreated.

Non-surgical treatment

The first line of therapy for chalazia is non-surgical therapy.

• Locally: antibacterial and steroid eye drops and ointments are prescribed.
• Antibiotics: therapy is empirical. Broad-spectrum agents, such as fluoroquinolones, are the drugs of choice.
• Systemic therapy: oral antibiotics are rarely used (only in cases of severe inflammation). In the event of a severe toxic-allergic reaction and significant eyelid edema, oral antihistamines are recommended.

Injection treatment

If a chalazion is recurrent or when non-surgical treatment is ineffective, it may be necessary to inject corticosteroids (betamethasone) into the chalazion cavity.

The probability of success after a single injection is about 80%. A repeat injection can be given after 1-2 weeks.

Surgical therapy

Removal of the chalazion is performed if non-surgical methods fail or the formation is too large. Course of the procedure:

1. Local anesthesia.
2. Application of a special final clamp on the eyelid.
3. Vertical incision of the prominent cyst through the tarsal plate (from the conjunctiva side).
4. Scraping out the contents with a curette and capsule.