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Page 1: Lacrimal system for undergraduates
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By/Mohamed Ahmed El –Shafie

Assistant Lecturer in ophthalmology department KafrELShiekh University

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The lacrimal system consists of two parts:

• Structures that secrete tear fluid.

• Structures that facilitate tear drainage.

LACRIMAL SYSTEM

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It lies beneath the superior temporal margin of the orbital bone in the lacrimal fossa of the frontal bone

It is neither visible nor palpable A palpable lacrimal gland is usually a sign of a pathologic change such as dacryoadenitis or tumors.

LACRIMAL GLAND ANATOMY

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The tendon of the levator palpebrae

muscle divides the lacrimal gland into a larger orbital part (two-thirds) and a

smaller palpebral part (one-third).

LACRIMAL GLAND PARTS

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Several tiny accessory lacrimal glands

(glands ofKrause and Wolfring) located in the

superior fornix secrete additional seroustear fluid.

ACCESSORY LACRIMAL GLAND

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Tear Flow Physiology

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may be due to one of two causes:• Reduced tear production in certain systemic disorders (such as Sjögren’s syndrome and rheumatoid arthritis) or as a result of atrophy or destruction of the lacrimal gland.• Altered composition of the tear film due to vitamin A deficiency, medications (such as oral contraceptives), or certain environmental influences (such as nicotine smoking, or air conditioning). The tear film breaks up too quickly and causes corneal

drying and scarring.

DRY EYE

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Patients complain of

• Burning, reddened eyes, and excessive lacrimation (reflex lacrimation) from only slight environmental causes such as wind, cold, low humidity, or reading for an extended period of time.• A foreign body sensation is also present.• May be accompanied by intense pain. • Vision is usually minimally compromised .

DRY EYE SYMPTOMS

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Bitot’s spots: interpalpebral conjunctival foamy patches associated with severe vitamin A & xerophthalmia

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FLUORESCEIN DYE DISAPPEARANCE TESTInstill 2 drops of fluorescein dye in the conjunctival sac and observe after 2 minutes

Normally no dye is seenProlonged retention of dye indicate inadequate drainage

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JONES TEST I

Instill 2 drops 2% fluorescein dye in the conjunctival sac, place a cotton bud dipped in 1% xylocaine in the inferior meatus, inspect the bud after 5 minutes.

Positive test- patent passages (may be hypersecretion)

No staining- Negative test

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JONES TEST II

If Jones I is negative, do Jones II

Place a bud similarly and perform lacrimal syringing

Positive test- lacrimal pump failure

Negative test- mechanical obstruction

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DACRYOCYSTOGRAPHY

To visualize the passage and know the exact site, nature and extent of block.

Inject radioopaque material in the sac.Take X-rays after 5 and 30 minutes

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Congenital nasolacrimal duct obstruction

Delayed canalizationCan be bilateralReflux of purulent material from punctum

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Acute dacryocystitisAcute inflammation of sac or pericystic area

leading to acute pain, swelling, redness and watering from the eye.

No interference like syringing,probing etc.

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DacryocystorhinostomyDCR

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QuizSigns of acute dacryocystitis:Dry eyesPainless swelling Redness &Watering

Nasolacrimal duct opens-in the nose- at:Superior meatus Middle meatusInferior meatus