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Flashcards in Lacrimal glands Deck (15):
1

Diseases of the Lacrimal system

Abnormal tear film
1. Aqueous layer deficiency: Keratoconjunctivitis sicca
2. Lipid and mucin layer deficiency
3. Eyelid abnormalities
4. Ocular surface abnormalities

Lacrimal drainage apparatus abnormalities
1. Obstruction
2. Acute Dacryocystitis
3. Chronic Dacryocystitis
4. Trauma

2

Aqueous layer deficiency: Keratoconjunctivitis sicca

causes
clinical
Treatment

Causes:
1. Idiopathic
- Postmenopausal woman
- Associated with dryness of mouth and genitals
2. Injury of Lacrimal gland
- Infection
- Surgery
- Autoimmune
- CT disorders: RA
3. Occlusion of draining system: cicarticial conjunctival diseases:
- Chemical burns
- Trachoma
- Stevens-Johnsons syndrome

Clinical:
- Burning and scratching eyes (> wind and aircon)
- Dryness
- Corneal vascularization
- Opacification
- Keratinization
- Secondary infection (< antibacterial activity of tear film and ep damage)

Treatment:
1. Avoid triggers
2. Artificial Tears: Used reguraly, Try different products, try different application frequency
3. Preservative free cartridges for one day use --> these avoid the problems of preservative sensitivity and irritation.
4. Gels @ night: greater relief, but interfere with vision
5. Ointments only in severe cases: cause blurring of vision and feel unpleasant in the eye.

3

Lipid and mucin layer deficiency
Causes
Clinical picture
Treatment

Causes:
1. Blepharitis: < in the lipid layer secreted by the tarsal glands.
2. Condition that leads to > destruction of mucous secreting conjunctival goblet cells will cause a mucin deficiency.
(a) Cicatricial conjunctival diseases such as chemical burns, trachoma and Stevens-Johnson syndrome.
(b) Xerophthalmia (vitamin A deficiency).

Clinical picture:
1. Dry eye
2. Burning and scratching eyes
3. Paradoxical symptom of tearing.
4. Dry spots: Tear film instability--> irritation and reflex aqueous tear secretion by the lacrimal gland to produce an excessive volume of fluid in the eye despite the dryness.
5. Corneal vascularisation, opacification and even keratinisation. (severe)

4

Eyelid abnormalities
Consequences
Causes
Treatment

Consequences:
1. Inadequate wetting of parts of the cornea. 2. Keratitis
3. Initially damage is confined to the epithelium--> vascularisation, opacification and eventually keratinisation.

Causes:
1 Abnormal eyelid contour
(a) Trauma
(b) Trachoma
(c) Tumour
2 Disruption of eyelid movements
(a) Lagophthalmos (incomplete eyelid closure): VII paralysis.
(b) Symblepharon (adhesion between palpebral and bulbar conjunctiva): trauma, trachoma, Stevens-Johnson syndrome.

5

Ocular surface abnormalities
Causes
Pathophysiology
Treatment

Causes:
1. abnormal contour
2. abnormal epithelium: pterygium or scarring.

Pathophysiology:
Abnormal contour or epithelium--> tear film turbulence/resist mucin adhesion--> unstable tear film--> formation of dry patches.

6

Obstruction in neonates and infants
Physiology
Incidence
Pathophysiology
Clinical picture
Complications
Treatment
Prognosis

Physiology: Obstruction to tear outflow --> tears collecting in the conjunctival sac--> flowing over the lid margin. This is called epiphora.
Obstruction causes stasis which predisposes to acute and chronic infections of the lacrimal sac.
Incidence: 5% of neonates
Pathophysiology: thin membrane occludes the nasal orifice of the nasolacrimal duct
Clinical picture: tearing and discharging eyes
Complications: Acute dacryocystitis
Prognosis: 90% of cases the tearing clears spontaneously by about 12 months of age.
Treatment:
1. Massaging the lacrimal sac twice a day,
2. Probing: If the problem is not resolved by 12 months of age

7

Acute Dacryocystitis

path
clinical
treatment

Pathophysiology:
Obstruction of tear film distal to lacrimal sac--> stasis--> secondary infection --> Lacrimal duct fills with puss--> Cellulitis

Clinical
- Epiphora
- Pain
- Redness of lacrimal sac
- Swelling of lacrimal sac
- Abcess with discharge

Treatment:
1. AB local and systemic
2. Abcess drainage
3. Dacryocystorhinostomy when infection cleared: Opening from lacrimal sac to nasal opening

8

Chronic Dacryocystitis

path
clinical

Pathophysiology:
Obstruction of tear flow distal to lacrimal sac--> Stasis--> secondary infection--> lacrimal sac fills with material--> chronic irritation of eye

Clinical
-Epiphora
-Mucopurulent discharge
- Swelling over Lacrimal sac
Pressure on Lacrimal sac causing mucopurulent material expressed from puncta

Treatment:
1. Dacryocystorhinostomy

9

Trauma

Path
clinical
treatment

Path: Canalicular injury
Clinical: lower and upper across each other--> if shifted--> abnormal
Treatment: Surgical Repair

10

Anatomy of Lacrimal system: Tear film

3 layers of tear film:

1. Outer lipid layer
- secreted: Tarsal glands
- function: Retards evaporation of the aqueous layer
Prevent tears from spilling over the edge
2. Middle Aqueous layer
- secreted: Lacrimal glands
3. Inner Mucin layer
- secreted: Conjunctival goblet cells
- function: Hydrophilic surface on which aqueous layer can be spread

11

Physiology of Lacrimal system: tear film

Structure unstable--> stabilized by methods:
-renewed by blinking- need normal 3 layers of tear film
- Corneal epithelium surface must be smooth and normal
- Good eyelid apposition
- Good contact of eyelids and anterior surface of eye

Irregular areas--> unstable tear film--> dry spots
- tear film turbulence--> mixing of layers
- mucin adhesion

12

Lacrimal drainage system anatomy

1. Lacrimal sac
2. Inferior punctum
3. Inferior canaliculus
4. Inferior turbinate
5. Nasalacrimal duct

13

Lacrimal drainage system physiology

Blinking--> tears to flow to the medial canthus --> siphoned into the canaliculi--> squeezed into the lacrimal sac--> They flow down the nasolacrimal duct and into the nose.

14

Lacrimal drainage system anatomy

1. Lacrimal sac
2. Inferior punctum
3. Inferior canaliculus
4. Inferior turbinate
5. Nasalacrimal duct

15

Lacrimal drainage system physiology

Blinking--> tears to flow to the medial canthus --> siphoned into the canaliculi--> squeezed into the lacrimal sac--> They flow down the nasolacrimal duct and into the nose.