Structures Forming Lacrimal Apparatus

Give a short account of parts, relation & nerve supply of lacrimal gland (or) Nasolacrimal apparatus (or) Name the structures forming lacrimal apparatus
Answer:

Lacrimal Gland Parts

1. Lacrimal gland and its duct:

1. Lacrimal gland:
   • Lacrimal gland is serous ‘J’ shaped gland
     Lacrimal gland Site:
   • In the lacrintal fossa on the anterolateral part of the roof of the bony orbit & partly on the upper eyelid
     Lacrimal gland Parts:
   • Orbital part: larger & deeper
   • Palpebral part: smaller & superficial
2. Lacrimal duct:
   • Lacrimal duct pierces the conjunctiva of the upper eyelid, open into the conjunctival sac at the superior fornix
   • Most of the ducts of orbital part pass through the palpebral part

“Understanding the structures forming the lacrimal apparatus through FAQs: Anatomy, functions, and uses explained”

Conjunctival Sac

1. Palpebral conjunctiva:
   • Lines the deep surface of eyelids
   • Palpebral conjunctiva is thick, opaque, highly vascular & adherent to tarsal plate
2. Bulbar conjunctiva:
   • Lines the front of eyeball
   • Bulbar conjunctiva is thin, transparent & loosely attached to eyeball
   • Conjunctival Ssac is the potential space between bulbar & palpebral part
3. Conjunctival fornices:
   • The lines along which the palpebral conjunctiva of the upper & lower eyelids is reflected on eyeball

“Importance of studying the lacrimal apparatus for medical students: Questions explained”

Lacrimal puncta & canaliculi

• Lacrimal canaliculi is 10 mm long structure beginning at lacrimal punctum
• Lacrimal canaliculi has
  • 2 mm long vertical part
  • 8 mm long horizontal part
• Lacrimal canaliculi has dilated ampulla at the bend
  • Opening
• In the lateral wall of the lacrimal sac behind medial palpebral ligament

4. Lacrimal Sac:

• Lacrimal Sac Site: lacrimal groove behind medial palpebral ligament
• Lacrimal Sac Size: 12 mm long & 5 mm wide
  Lacrimal Sac Parts:
• Upper end is blind
• Lower end continuous with nasolacrimal duct
  Lacrimal Sac Relations:
• Anteriorlymedial palpebral ligament, orbicularis oculi
• Mediallylacrimal groove
• Laterallylacrimal fascia & lacrimal part of orbicularis oculi

“Common challenges in mastering lacrimal apparatus notes effectively: FAQs provided”

5. Nasolacrimal Duct:

• Nasolacrimal Duct is 18 mm long membranous passage
  Nasolacrimal Duct Course:
• Begins at lower end of lacrimal sac
• Runs downwards, backwards & laterally
• Opens into inferior meatus of nose

Valve of Hasner:

• Valve of Hasner is a fold of mucous membrane forming imperfect valve at lower end of duct

Valve of Hasner Nerve Supply:

“Factors influencing success with lacrimal apparatus studies: Q&A”