Blepharitis

Question 1

What are Meibomian glands?

Answer 1

Meibomian glands are modified sebaceous glands, located within the tarsal plates of the eyelids, responsible for secretion of the oily layer of the tear film

Question 2

Function of the oily layer of the tear film?

Answer 2

1. prevents tear evaporation
2. reduces the surface tension of the tear layer
3. facilitates the spread of tears
   - It is critical for normal eye lubrication.

Question 3

What is blepharitis?

Answer 3

Blepharitis is an inflammation of the eyelid margin that affects the eye lashes or tear production.

Question 4

Epidemiology of blepharitis?

Answer 4

• Blepharitis is not specific to any group of people. It affects people of all ages, ethnicities, and gender.
• The mean age of people with all types of blepharitis is 50 years.
• Compared to other forms of blepharitis, staphylococcal blepharitis is more common at a slightly younger age (mean 42 years) and affects predominantly females (80%).
• Blepharitis is more common in adults than children, and its prevalence increases with age

Question 5

Infectious causes?

Answer 5

1. Bacterial: Staphylococci (most common causative pathogen)
2. Viral: Herpes simplex, varicella zoster
3. Fungal: Molluscum contagiosum
4. Parasitic: Demodex eyelash mites

Question 6

Etiology of blepharitis?

Answer 6

1. Endogenous factors
   - oily deposits, hypersecretion of the eyelid glands, accumulation of secretion from the meibomian glands
2. External factors
   - smoke, dust, dry indoor climate, chemicals, drug toxicity
3. Systemic diseases
   - rosacea, psoriasis and seborrheic dermatitis
4. Ocular diseases
   - dry eye syndromes (e.g., Sjögren syndrome), chalazion, trichiasis, conjunctivitis, and keratitis

Question 7

Pathophysiology of blepharitis?

Answer 7

1. Involves bacterial colonization of the eyelids.
2. This results in direct microbial invasion of tissues, immune system–mediated damage, or damage caused by the production of bacterial toxins, waste products, and enzymes.
3. Colonization of the lid margin is increased in the presence of seborrheic dermatitis or meibomian gland dysfunction.

Question 8

Risk factors of blepharitis?

Answer 8

1. Poor eye hygiene
2. Wearing contact lenses
3. Not removing makeup thoroughly
4. Having oily skin
5. Having allergies
6. Having rosacea

Question 9

Classification of blepharitis based on location?

Answer 9

1. Anterior blepharitis
   - inflammation of the anterior margin of the eyelids, involving the skin, eyelashes, and follicles
   - It can further be classified into staphylococcal and seborrheic.
2. Posterior blepharitis
   - inflammation of the posterior margin of the eyelids; associated with meibomian gland dysfunction and/or obstruction (meibomitis) as well as abnormalities of the tarsal plate.

Question 10

Describe acute blepharitis?

Answer 10

1. Acute ulcerative blepharitis
   - May be bacterial (Staph) or Viral (herpes simplex, varicella zoster)
2. Acute non ulcerative
   - Due to allergic reactions localized in the same area
   e.g. Allergic blepharon-dermatitis, Seasonal allergic blepharon-conjunctivitis

Question 11

Describe chronic blepharitis?

Answer 11

• Noninfectious
• Meibomian gland dysfunction leads to abnormal lipid composition hence blocked gland ducts with hard, waxy plugs
• Seborrheic blepharitis with secondary bacterial colonization in the scales developing on the eyelid margin blocking the Meibomian glands

Question 12

Signs and symptoms of blepharitis?

Answer 12

1. Chronic or recurrent red, swollen eyelids and irregular eyelid margins
2. Burning sensation
3. Tearing
4. Itchiness
5. Grittiness or foreign body sensation
6. Photophobia and blurred vision
7. Madarosis - loss of eyelashes
8. poliosis - localized patches of hypopigmented hair due to reduction or absence of melanin
9. trichiasis - inward growth of eyelashes

Question 13

Physical signs and symptoms of blepharitis and what they represent?

Answer 13

1. Crusty, scaly plaques, and/or oily deposits on the eyelid margin and eyelashes
   - Crusting usually represents seborrheic disease.
2. A ring-like collection around the eyelashes (collarette) with ulceration upon removal (ulcerative blepharitis) is typical of staphylococcal disease.
3. A smooth tubular collection at the base of the eyelash is typical of Demodex

Question 14

Mnemonic for blepharitis synptoms?

Answer 14

LIGHTS
L - loss of eye lashes
I - itchy eyelids, irritation
G -grittiness
H - light sensitivity
T - excessive tears
S -scales on lid margin

Question 15

Diagnosis of blepharitis?

Answer 15

Blepharitis is a clinical diagnosis based on characteristic findings of redness and irritation of the eyelid margin associated with crusting or flakes on the lashes or lid margins.

Question 16

Ddx for blepharitis?

Answer 16

1. Infections
   - Bacterial: Impetigo, erysipelas
   - Viral: Herpes simplex, varicella zoster
2. Dermatoses
   - psoriasis, dermatitis
3. Malignant eyelid tumors
   - Basal cell carcinoma, melanoma
4. Other ophthalmological conditions
   -Ocular rosacea
   - Bacterial keratitis
   - pre-septal cellulitis
   - conjunctivitis
   - stye
   - keratoconjunctivitis sicca (KCS)

Question 17

Management of blepharitis?

Answer 17

General
1. Eyelid hygiene (Mainstay treatment)
Medical
2. Topical antibiotics such as erythromycin, Bacitracin, Azithromycin.
3. Oral antibiotics: Doxycycline, Tetracycline, Azithromycin
4. Topical steroids like glucocorticoids (in cases of severe inflammation)
5. Eye drops

Question 18

Therapeutic procedures of blepharitis?

Answer 18

1. BlephEx treatment (electromechanical lid margin debridement)
   - A spinning brush is used to gently clean and exfoliate the eyelids, removing debris and bacteria.
2. Thermal pulsation treatment e.g. LipiFlow
   - It works by applying heat and pressure to the eyelids which helps unclog meibomian glands and restore healthy oil production.
3. Intense Pulsed light (IPL)
   - It works by applying heat and pressure to inner eyelids, loosening and liquefying blocked meibomian glands and resume normal flow of oils into the tear film.

Question 19

Prognosis of blepharitis?

Answer 19

• Overall, the prognosis for patients with blepharitis is good.
• Blepharitis only causes significant morbidity in an extremely small subset of patients.
• Patients with chronic blepharitis experience a considerable amount of discomfort that can greatly reduce their well-being and ability to carry out the daily activities of life and work.

Question 20

Complications of blepharitis?

Answer 20

Conjunctivitis
Chalazion
Marginal keratitis
Ectropion
Entropion
Recurrence