Intubation options
Monocanalicular stents
- Varieties
- With guide wire, retrieved from nasal cavity
- Without guide wire, pushed down canaliculi
- Benefit
- Retrieval in nose may not be required
- Can be performed without general anesthesia
- Easier removal, pulled out through puncta
- Disadvantage
- Smaller girth: single stent at level of common canaliculi and onward
- Seating in puncta may be less stable
Bicanalicular stents
- Varieties
- With long guide wire: retrieved with groove director or hemostat
- With olive tip: can be hooked in the nasal cavity
- Patent for threading of suture: Suture is pulled out nasal cavity dragging stent through lacrimal drainage duct.
- Pigtail (ring stent): looped through canaliculi system
- Variable thickness, with thin interpunctal segment
- Some brands attached to long olive tip probe
- Some brands with short guide wire that pushes stent into duct, then pulls out from above, avoiding the need to rescue the probe in the nose
- Benefit
- Secure: less likely be lost/fall out
- Can increased girth with two stents
- Disadvantage
- Can cause abnormal enlargement of puncta, i.e., cheese-wiring
- Can be challenging to remove
Anesthesia
General anesthesia
- Usually needed when stents are retrieved within the nasal cavity
Local anesthesia with/without sedation
Nasal cavity passage is too uncomfortable for most patients.
Monocanalicular stents (without the guide wire) can be placed under local anesthesia.
Nasal decongestion/vasoconstriction
- Useful for procedures involving entry into nasal cavity
Technique
Monocanalicular intubation
- Punctal dilation
- Variety
- No guide wire: simply push into distal canaliculi
- With guide wire: passed through lacrimal drainage system, same as with bicanalicular stents.
- Seating of punctal plug portion of monocanalicular stent in punctum, or suturing of free end of tube anterior to punctum
Bicanalicular intubation (ring intubation)
- Punctal dilation
- Introduction of pig-tail probe
- Careful passage of pig-tail probe through both canaliculi
- Placement of silicone tubing loop containing internal suture in lumen
- Tying of internal suture with rotation of tied ends of tubing into canaliculus
Bicanalicular intubation (nasolacrimal duct)
- Nasal decongestion/anesthesia
- Punctal dilation
- Passage of probe attached to tubing through canaliculus into lacrimal sac, and down nasolacrimal duct with retrieval of probe from inferior meatus (with/without endoscopy)
- Passage of second probe through other canaliculus in similar fashion
Tying/suturing of tubing ends in nasal vestibule
- +/- suturing of tubing knot to mucosa of lateral nasal wall
- A variation is to avoid knotting the stent, but rather join the 2 arms with a tight wrap-around absorbing suture, which is then tied to the nasal wall. When the suture absorbs, the stent will fall out or can be pulled out from above.
Bicanalicular intubation performed with DCR, etc.
- Passage of probes through canaliculi into DCR ostium
- Intranasal probe retrieval from ostium
- Tying/suturing/securing of tubes as above
Intubation with microendoscopic intracanalicular visualization
- Might decrease incidence of false passage, but equipment not widely available