Fig. 19.1
Example of an upper canalicular laceration
In order to inspect the canaliculus the punctum is dilated first. A size “00” Bowman probe can then be passed through the punctum. A laceration can be confirmed if the dilator or probe is visualized distal to the punctum (Fig. 19.2). If there is difficulty in passing the probe, canalicular injury must be suspected as well. In addition, irrigation can be performed and flow of solution out through the open wound is highly suggestive of canalicular involvement. In patients with a laceration near the medial canthus, flow of irrigation fluid out through the wound can indicate a lacrimal sac laceration.
Fig. 19.2
Canalicular laceration with punctal dilator visualized in the wound after being placed through the punctum and proximal canaliculus
In a patient with burns to the eyelids, the authors recommend examination of the punctae to note any degree of stenosis. The punctae can then be dilated and a probe and irrigation of the canaliculus can be performed. This will help to determine if there is any degree of canalicular stenosis.
As mentioned previously patients with fractures of the midface are prone to disruption of the lacrimal sac and/or nasolacrimal canal/duct. The surgeon needs to review the imaging studies to determine if there may be any disruption of the lacrimal sac or nasolacrimal duct. These are patients in whom it may be beneficial to perform probing of the nasolacrimal duct soon after the trauma to assess the extent of injury, especially if the patient is acutely symptomatic; although caution is advised since probing can potentially cause further iatrogenic damage. These injuries are usually identified while the patient is under anesthesia and a proper probe and irrigation can be performed [4].
Management of Injuries
Canalicular Laceration
Repair of canalicular lacerations at one time always involved taking the patient to the operating room to place a bicanalicular stent and closure of the eyelid defect. More recently monocanalicular stents have been introduced which has allowed for repair of canalicular injuries under local anesthesia in the ER or office.
The use of oral antibiotics in these types of lacerations is somewhat controversial. The surgeon can consider prescribing a broad spectrum antibiotic for patients with “dirty” wounds such as a dog bite, although there is some evidence that this is not necessary in this situation [9].
The surgeon first needs to identify the medial end of the cut canaliculus in order to properly repair a canalicular laceration. This is often the most difficult part of the repair. The cut end usually appears as a glistening white ring with rolled edges. The canaliculus is easier to identify if the laceration is closer to the punctum. In patients with more medial lacerations the canalicular injury will be in the deeper tissue, often deep to the medial canthal tendon. A Bowman probe can be place through the punctum and intact canaliculus to help judge where the cut end may be. If the medial cut end still cannot be identified, fluorescein dyed saline can be injected in the intact canaliculus on the same side and the surgeon can attempt to determine where it exits the wound. Alternatively, air can be injected while the medial tissues are submerged under saline.
In order to properly repair the canaliculus we recommend that a stent be placed to keep the canaliculus open while it heals [10]. The standard for many years in the repair of canalicular lacerations was the use of bicanalicular intubation. This involves the use of nasal packing to obtain sufficient anesthesia along with intravenous sedation or general anesthetic. More recently monocanalicular stents have become popular. These can be inserted under local anesthesia. The disadvantage of these stents is that they are less secure and can become dislodged, especially in children. In addition, any disruption of the punctum generally precludes use of this stent because it will likely not seat properly.
For repair with a bicanalicular stent, the authors prefer the use of the Ritleng system (FCI Ophthalmics Inc.) (Fig. 19.3). After punctal dilation the Ritleng probe is inserted into the proximal intact portion of the canaliculus. It is then passed through the medial cut end and then advanced until a hard stop is felt. The probe is then rotated superiorly along the brow and then passed through the nasolacrimal duct into the nasal cavity just below the inferior turbinate. The PolyEtherEtherKetones (PEEK) thread guide which is attached to the silicone stent is then passed through the Ritleng probe into the nasal cavity. The thread can be retrieved from the nose with a Ritleng hook (Fig. 19.4), which is then pulled through until the stent is identified in the nose. The probe can then be removed from the lacrimal system, leaving the stent in place. If the laceration is near the punctum, there is a risk for tearing the punctum when rotating the probe. In these instances the thread/stent can be passed through the punctum and proximal canaliculus first, and then pulled out through the wound. The probe can then be inserted into the medial cut end of the canaliculus. At this point the probe can be rotated superiorly and passed into the nasal passage without inducing a large amount of medial traction on the punctum. This procedure is performed again for the adjacent canaliculus. The PEEK threads are removed from both sides of the stent, and the stent is tied in the nose with a single square knot. The knot may or may not be secured to the wall of the nasal passage with a suture depending on surgeon preference.
Fig. 19.3
Ritleng bicanalicular intubation system with the probe and thread guide
Fig. 19.4
Ritleng hook with thread guide
The monocanalicular stent (Mini-Monoka, FCI Ophthalmics Inc.) is a short silicone tube with a phalange at the proximal end (Fig. 19.5). When using this stent for a canalicular laceration, it is initially passed through the punctum and proximal canaliculus so the phalange is seated appropriately within the punctum. This secures the stent into place. The stent can be pulled from the cut end of the canaliculus to help seat it properly. It is then threaded through the medial cut canaliculus into the lacrimal sac. It does not need to be advanced into the nasolacrimal duct; therefore it can be shortened if needed.
