Canalicular lacerations are commonly associated with trauma to the eyelids. Since the dense fibrous tissue of the tarsus is much stronger than the medial canalicular portion of the eyelid, any tractional force along the eyelid margin can result in medial eyelid avulsions with canalicular involvement.

To minimize the risk of scarring and epithelialization of the wound, canalicular lacerations should be repaired within one day of the injury. In young children, the repair usually requires taking the patient to the OR for general anesthesia. In adults, the repair can often be accomplished under local anesthesia.

Initial Technique
Isolated canalicular lacerations usually can be repaired rapidly once all supplies have been gathered. Surgical loupes facilitate visualization of the canalicular structures.

When infiltrating the tissues with local anesthetics, an excessive amount of anesthetic should be avoided, as this may impair identification of the cut ends of the canaliculus. We prefer to use a concentrated anesthetic with epinephrine (2 percent lidocaine with epinephrine) to reduce bleeding. After a Betadine prep, the wound should be carefully inspected to locate the cut edges of the canaliculus prior to further manipulation. The key to successful repair is intubation of the canaliculus with a silicone stent to prevent stenosis as the laceration heals. The type of stent used depends on the location of the laceration, whether one or both eyelids are lacerated, and whether both ends of the laceration can be easily identified.

Monocanalicular Intubation
When both ends of a single canalicular laceration can be visualized clearly, the simplest method of intubating the canalicular system is with a monocanalicular stent. These stents have a collar at one end to secure themselves in the punctum similar to silicone punctal plugs.

Technique. The stent is first threaded through the punctum with the metal stylet and retrieved at the distal cut end of the laceration. The collar of the stent is placed securely in the punctum so that the top edge is flush with the eyelid margin. The stent is then cut to the appropriate length to bridge the laceration. The length of the stent should be cut with excess remaining, as a small amount of excess stent should extend into the nasolacrimal sac. The stent is then placed into the proximal (medial) cut end of the canaliculus. The laceration is then repaired as described below. (See “Completing the Repair.”)

Pros and cons. The advantage of this stent is that it does not involve manipulation of the opposite canaliculus or manipulation in the nose. The disadvantage is that, like punctal plugs, the patient can accidentally displace it. Removal often requires a slit lamp and may be difficult to accomplish in children. If the canalicular laceration is located more medially, identification and intubation of the proximal (medial) cut end may be difficult, which precludes the use of this stent.

Bicanalicular “Doughnut” Intubation
In cases where the proximal end of the laceration cannot be readily visualized, we prefer to intubate the canaliculus with a bicanalicular “doughnut” stent.

“Doughnut” intubation is accomplished by passing a silicone stent through one punctum and its corresponding canaliculus into the opposite canaliculus to exit through the other punctum. This is done using the Worst round, eyed pigtail probe.

Technique. Although there is a learning curve to using the pigtail probe, it is extremely useful when the proximal end of the canalicular laceration is not readily identified. The pigtail probe is first introduced into the punctum opposite the laceration. It is then gently rotated within the canalicular system to advance the probe toward the common canaliculus. Since the canaliculus lies posterior to the medial canthal tendon, a slightly posterior direction may facilitate passage of the probe into the opposite canaliculus. Excessive force should be avoided to minimize canalicular trauma and reduce the risk of creating a false passage. In extremely rare cases, a common canaliculus may not exist, and the canaliculi enter the sac independently. The pigtail probe would not be useful under these circumstances and may cause damage.

Once the pigtail probe has entered the lacerated canaliculus, continued rotation will expose the end of the probe through the proximal cut end of the canaliculus. A 6-0 prolene suture is threaded through the eyelet, and the probe is rotated in a retrograde manner to pull the suture through the canalicular system. The probe is then placed through the punctum of the lacerated eyelid to pull the other end of the suture through the distal cut end of the canaliculus and through the remainder of the canalicular system. A silicone stent measuring approximately 25 millimeters is threaded over the suture and clamped to the suture with a needle holder. The suture is then pulled with the stent through the canalicular system, bridging the canalicular laceration. The prolene suture is then tied together with several knots, and the stent is rotated so that the knots lie within the lacrimal sac.

Pros and cons. The advantage of “doughnut” intubation using the pigtail probe is that it facilitates identification and intubation of the proximal end of the transected canaliculus. The stent is also almost impossible to accidentally dislodge or remove. Successful intubation usually requires the presence of a common canaliculus, which in the literature has been estimated to be present in 90 percent of patients. We strongly question this figure, however, as in our experience, we have noted that less than 2 percent of patients undergoing dacryocystorhinostomy lack a common canaliculus. In the remaining patients who lack a common canaliculus, passage of the pigtail probe would be very difficult or impossible.

Care should be taken not to make the stent too tight, as this may result in punctal and canalicular erosion. To remove the stent, the “doughnut” is rotated 180 degrees so that the knot is exposed. The knot is cut and the stent removed.

Bicanalicular Nasolacrimal Duct Intubation
Bicanalicular nasolacrimal duct intubation should be considered in children (as removing the stent may be more challenging than repairing the laceration) and in cases of upper and lower canalicular lacerations. We prefer using the Crawford intubation stents, since the metal probe with the olive tip minimizes trauma to the mucosa.

Technique. The inferior nose should first be sprayed with a nasal decongestant, then packed with cottonoids soaked in 4 percent cocaine. The medial end of the canalicular laceration or lacerations must be visualized. The Crawford probe is first placed through the punctum and out the distal end of the laceration. The probe is placed into the medial end of the laceration, into the nasolacrimal sac, and then down the nasolacrimal duct. Retrieval under the inferior turbinate in the nose can be greatly facilitated with a groove director (JedMed). The other end of the probe is then placed through the opposite punctum and canaliculus and retrieved in the nose with the groove director. The stent is tied together with four single-throw knots and secured to the nasal alar with a 4-0 polyglactin suture. It is important to allow laxity in the stent when it is tied to avoid retraction into the nasolacrimal duct or tension on the puncta.

Pros and cons. The advantage of bicanalicular nasolacrimal duct intubation is that when the stent is to be removed, it can be pulled out through either the nose or the canalicular system. The procedure is identical to that used when intubating the nasolacrimal system in infants and children for tearing. The disadvantage is that the medial end of the lacerated canaliculus must first be identified, which may be difficult if the laceration is more medial.

The procedure also requires intranasal packing and manipulation, which may cause discomfort if the patient is not sedated. The stents also can be accidentally displaced if the patient is not careful.

Completing the Repair
Once the canaliculus has been intubated and the laceration has been bridged, the medial canthal tendon structures should be reconstructed carefully, to ensure that the punctum is returned to its normal position medially.

If a notch is present in the medial eyelid, the patient will tear despite a successful canalicular repair. It is extremely important to get a good eyelid margin repair. While direct microscopic anastomosis of the canaliculus has been advocated, this may actually induce more trauma to the canalicular epithelium and result in a greater risk of stenosis. We prefer to simply approximate the pericanalicular soft tissues. This invariably will bring the canalicular ends together over the indwelling stent. A 4-0 polyglactin suture is placed in the pericanalicular tissue of the distal cut end of the laceration, or the medial tarsus if the laceration is more lateral. The suture is then fixated to the medial canthal tendon near the proximal end of the laceration. The remainder of the laceration is then closed in a routine manner. The silicone stents should be left in place for at least three months.

In summary, repairing canalicular lacerations can be a simple and successful procedure if the surgeon is aware of all the options available. Canalicular lacerations should be repaired promptly (within 24 hours of the injury) and should always be intubated with a silicone stent. Familiarity with canalicular repairs allows the surgeon to provide a service to emergency rooms that most other specialties are hesitant to provide.


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Dr. Yen is assistant professor of ophthalmology at Baylor College in Houston. Dr. Anderson is medical director of the Center for Facial Appearances, Salt Lake City.