Lacrimal System And Dry Eye

Question 1

the tear film is composed of three layers secreted by ___

Answer 1

1. outer layer (Lipid) by meibomian
2. middel (Aqueous) by lacrimal
3. inner (Mucin layer) by goblet cells

Question 2

can you enumerate the lacrimal system disorder

Answer 2

1. acute / chronic / infantile dacryocystitis
2. acute / chronic dacryadenitis
3. dry/watery eye
4. Canaliculitis

Question 3

excessive lacrimation (watery eye) called

Answer 3

Epiphora

Question 4

Congenital naso-lacrimal duct obstruction called

Answer 4

Congenital or infantile dacryocystitis

Question 5

infantile dacryocystitis caused by

Answer 5

mainly by obstruction of hasner’s valve

Question 6

clinical features of infantile dacryocystitis

Answer 6

1. epiphora
2. recurrent conjunctivitis.
3. Pressure over the lacrimal sac leads to reflux of clear fluid, mucus, muco-pus or sometimes pus.

Question 7

treatment of infantile dacryocystitis

Answer 7

1. conservative (antibiotic + massage) for 6 months
2. Probing carefully [1]
3. Repeated syringing & irrigation (curative)
4. Silicone intubation
5. Dacryo-Cysto-Rhinostomy (DCR)

[1] lacrimal sac still elastic

Question 8

in Acute Dacryocystitis regagitation test is +ve o -ve?
and why?

Answer 8

-ve.. congestion of the epithelium of canaliculi.

Question 9

complications of Acute Dacryocystitis

Answer 9

1. Lacrimal fistula: The sac may burst anteriorly through the skin.
2. Pyocele: Canaliculi may become obstructed.
3. Orbital cellulitis and cavernous sinus thrombosis.
4. Chronic dacryocystitis.

Question 10

treatment of Acute Dacryocystitis

Answer 10

1. During the acute phase:
   a. Antibiotics: Systemic and topical.
   b. Hot fomentations.
   c. Lotions: To clean the pus.
   d. Incision and drainage if an abscess forms.
2. After the acute attack subsides: Dacryocystorhinostomy with
   fistulectomy if needed.

Question 11

causes of dry eye

Answer 11

1. abscence of lacrimal gland
2. inflammation of the gland
3. tumors
4. Keratoconjunctivitis sicca
5. Conjunctival scarring (trachoma, chemical burns, Stevens-Johnson syndrome and ocular cicatricial pemphigoid.

Question 12

treatment of dry eye

Answer 12

1. Protective glasses and contact lenses.
2. Tear substitutes (eye drops, eye gel).
3. Occlusion of the puncti to reduce tear drainage.
4. Systemic steroids (autoimmune cases).