The Lacrimal Apparatus

It consists of the secretory portion and collecting portion. the secretory portion is composed of the lacrimal gland. The collecting portion consists of canaliculi with their orifices (puncti), the lacrimal sac and lacrimal duct which has its opening in the inferior nasal meatus.

The secretory portion

NB. Removal or gross injury to the palpebral part of the gland cuts off all the connecting ducts and this prevents the secretion of the entire gland.

Functions of the lacrimal gland

Blood supply

Nerve supply

Lymphatic drainage joins with the conjunctival lymphatics to drain into the pre-auricular lymph nodes.

COPIED from the book Clinical Anatomy of the Visual System.

The collecting portion


Lacrimal canaliculi

Lacrimal sac

Nasolacrimal duct (NLD)

Tear production and drainage

COPIED from the book Comprehensive Ophthalmology
  1. Eyes open, tears flow into puncta and canaliculi passively.
  2. Eyes closed, palpebral portion of orbicularis oculi muscle contracts, pulls lacrimal sac open creating a vacuum. Tears are then sucked from the canaliculi into the sac (blinking reflex) hence the lacrimal bulging.
  3. Eyes open, orbicularis oculi muscle relaxed leading to collapse of the lacrimal sac forcing the tears to drain into the NLD.