Canalicular lacerations can be caused by any type of trauma, from motor vehicle accidents to dog bites, coat hangers to tree branches. When a laceration is located medial to the punctum or involves the medial canthal tendon, the tear drainage system should be closely inspected for damage.
In part 1 of 'When Tearing is the Issue', inspection tips were given, including injection of air, viscoelastic or fluorescein through the intact edge of the system to look for bubbles, viscous fluid or dye emerging from the lacerated edge. As well, a Bowman probe can be placed through the punctum and canaliculus to look for exposure of the probe. It is important to also inspect for retained foreign bodies in the laceration, especially if a broken windshield or tree branch was involved in the trauma. This inspection is best done after local anesthesia has been given.
Treatment after inspection begins with irrigation of the lacerated area with an antibiotic solution. Next, locate the lacerated edges of the canaliculus. The damaged system should be stented first. There are various stents that can be used, including the Mini-Monoka monocanalicular stent, a donut silicone stent fashioned from a piece of Crawford stent, a full Crawford stent or a Goldberg Cerclage. If using a monocanalicular stent, feed the tube through the punctum, through the lacerated edge and into the lacrimal sac. The stent should be trimmed to allow the end of the stent to reach the sac. If a donut style stent is used, a pigtail probe is ideal for feeding through the system. The probe is placed through the intact punctum, exiting out through the lacerated edge. If using the full Crawford stent, the entire system must be stented with care not to create a false passage.
After the damaged system has been stented, the soft tissues surrounding the canaliculus should be approximated. Take bites with a 7-0 vicryl of the tissues adjacent to the stent for best approximation. The overlying skin can be closed with either 7-0 nylon or 7-0 vicryl if suture removal is to be avoided. Antibiotic ointment is applied to the wound three times per day for a week. Stents can remain in place for at least 3 months. Follow up every 6 weeks or so will allow the physician to check for cheese wiring or infection.
Occasionally the stent requires early removal if there is evidence of infection or inflammation. Be suspicious of an atypical mycobacteria infection if discharge, erythema and edema are present around the stent. Treatment beyond removal of the stent would be with topical and oral clarithromycin and/or amikacin potentially for several weeks to months until the infection clears.
Stenting of canalicular lacerations is successful in the majority of cases. If the system is badly scarred, a conjunctivodacryocystorhinostomy is sometimes needed.