Lacrimal Apparatus is the system which helps the secretion of tear fluid and its drainage. Here is the complete discussion of lacrimal apparatus i.e: Applied Anatomy, Applied Physiology, Drainage of tear, Watering, Pre-corneal tear film and Disease of Lacrimal gland and sac.
LACRIMAL APPARATUS
APPLIED ANATOMY:
A) Secretory Portion:
i)Lacrimal Gland
ii) Accessory Lacrimal Glands [Glands of Krause & Glands of Wolfring]
B) Drainage Portion:
i) Puncta: Superior & Inferior
ii) Canaliculi: Superior, Inferior, Common
iii) Lacrimal Sac
iv) Nasolacrimal Duct
APPLIED PHYSIOLOGY:
The tear is secreted from Lacrimal and Accessory Lacrimal Glands:
i) Evaporation
ii) Drain
iii) Form Aqueous Humour
DRAINAGE OF TEAR:
Tear > Conjunctival Sac > Puncta > Inferior Canaliculi > Common Canaliculi > Lacrimal Sac > Nasolacrimal Duct > Inferior Meatus of Nose.
WATERING:
It is the overflow of tear fluid.
a) Lacrimation: Due to lacrimal hypersecretion.
b) Epiphora: Due to lacrimal drainage problem:
i) Obstruction
ii) Malposition due to Ectropion or Entropion
iii) Lacrimal Pump Failure
PRE-CORNEAL TEAR FILM:
Consists of [Outside to Inwards]
a) Lipid bilayer: Outer layer, secreted by the Meibomian glands.
b) Aqueous layer: Middle Layer, secreted by the Lacrimal gland.
c) Mucin layer: Inner layer, secreted by the Goblet cells of the conjunctiva.
DISEASES OF LACRIMAL GLAND:
a) Dacryoadenitis: Inflammation of lacrimal gland.
b) Tumor: Pleomorphic adenocarcinoma, Benign Mixed Tumour
DISEASES OF THE LACRIMAL SAC:
a) Dacryocystitis: Inflammation of lacrimal sac.
Types: i) Infantile dacryocystitis
ii) Adult dacryocystitis: Acute, Chronic
Thanks for the post. Really informative.
Good information. Thanks.