This systems originates with the puncta (there is one in both the upper and the lower eyelid) and is a conduit for tears to travel from the eyelid through the nasolacrimal sac into the nose.

Tension, from trauma such as a blow from the fist, can result in an eyelid laceration which involves the canalicular system.

Repair requires re-approximation of the eyelid as well as re-approximation of the conduit; this is best achieved with a stent such as with silastic and fine sutures such as 6,7, or 8-0 vicryls..

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Technique Simplifies Lacrimal Intubation
(Ocular Surgery News, April 1, 1996)

• First the punctum is dilated (enlarged). 
• Next the medial (portion closest to the nose) cut end of the canalicular system is identified (this usually requires either high-powered magnifying loupes or an operating microscope). 
• The stent is then placed through the punctum, through the medial cut end of the canalicular laceration, and retrieved from the nose; if a mini-Monoka is used, no retrieval is performed. 
• The laceration is then reapproximated with fine sutures.

• Following dilation and preliminary probing of lacrimal ducts, the Ritleng Probe (S1-1460u) is introduced into the canaliculus and nasolacrimal duct until contact is made with the nasal fossa floor.

• The probe is pulled back slightly (1 cm) to facilitate the introduction of the prolene thread-guide into the nasal cavity.

• The probe is oriented with its slit side facing anteriorly and pushed backwards so that the inferior end of the probe is facing anterior, thus
  directing the prolene towards the front of the nasal cavity.

• The prolene is threaded through the probe to obtain a large loop which spreads out in the nasal cavity making it easy to locate. Retrieval of the blue prolene is easy when it appears in the anterior portion of the nose.

• The prolene is retrieved under nasal illumination and visual control (nasal endoscope) with endonasal forceps or with the Ritleng Hook (S1-1480u)

• If the prolene thread-guide is not easily located in the anterior portion of the nose, or if it takes a posterior direction, the following technique is used for retrieval:

  • The probe is introduced until contact is made with the nasal fossa floor.

  • Metal-to-metal contact is made using the Ritleng Hook (S2-1480u) high up in the inferior meatus near the exit of the nasolacrimal duct.
     

• The probe is then rotated 180 degrees while keeping the metal-to-metal contact with the hook thus orienting its inferior opening towards the back.

• The hook should be above the probe's opening and the prolene.

• This will enable the hook to catch the prolene loop when removing from the nose.

• The probe is slowly backed out of the inferior meatus and as soon as the metal-to-metal contact between the probe and the hook is lost, the hook catches the prolene loop and is carefully removed from the nose.

• The probe is removed from the canaliculus and detached from the stent by sliding the thinner light blue portion of the prolene out through the probe's slit.

• The prolene thread-guide is pulled out the nose along with the attached silicone tubing.

• This same technique is used to intubate the second canaliculus in the case of a bicanaliqilar intubation.
  In the case of a monocanalicular intubation, the punctal plug at the other end of the silicone tubing is seated in the punctum using a punctal plug dilator inserter (S1-3090u).