Eye on the Prize: Can You Perform a Lateral Canthotomy?

When a patient presents with orbital compartment syndrome, performing a lateral canthotomy and cantholysis can be vision-saving. You may only have 60-100 minutes until the patient experiences permanent visual sequelae. Are you ready?

Indications:

Indications to perform lateral canthotomy may be remembered with the mnemonic DIP A CONE. They include decreased visual acuity, intraocular pressure > 40 mm Hg (normal is 3-6 mm Hg), proptosis, afferent pupillary defect, cherry red macula, ophthalmoplegia, nerve head pallor, and eye pain. The only absolute contraindication is globe rupture.

Materials:

You won’t need many materials to perform this procedure. In fact, there are only six.

1. 1% epinephrine with lidocaine
2. 25-gauge needle
3. Syringe
4. Hemostat
5. Suture scissors
6. Toothed forceps

The procedure:

Step 1: Clean the area around the lateral canthus, and provide local anesthesia by injecting 1% lidocaine with epinephrine with a 25-gauge needle.

Step 2: Clamp the hemostat to the lateral canthus to crush it for 1-2 minutes. This should reduce incisional bleeding. Then cut through the crushed tissue with scissors.

Step 3: Use the toothed forceps to pull the lower eyelid away from the globe.

Step 4: Strum the tissue to identify the inferior crus of the lateral canthus, and cut through it. Direct your scissors inferiorly, perpendicular to the canthotomy cut you made in Step 2.

Step 5: If pressure is not relieved, cut through the superior crus as well.

Complications are rare. Cosmetic concerns are minimal. Try to avoid damage to the levator aponeurosis, lacrimal gland, and lacrimal arteries.

For a great video of this procedure, click here (thank you, Dr. Alerhand!): https://www.youtube.com/watch?v=MhGQ1ikN93M

References:

1. Custalow CB, Roberts JR, Thomsen TW, Hedges JR. Ophthalmologic procedures. In: Roberts and Hedges’ clinical procedures in emergency medicine, 6^th ed.
2. Ballard SR, Enzenauer RW, O’Donnell T, et al. Emergency lateral canthotomy and cantholysis: a simple procedure to preserve vision from sight threatening orbital hemorrhage. J Spec Oper Med. 2009;9(3):26-32.
3. Nickson, C. Bashed, blind and bulging. http://lifeinthefastlane.com/ophthalmology-befuddler-033-2/
4. McInnes G, Howes DW. Lateral canthotomy and cantholysis: a simple, vision-saving procedure. CJEM. 2002 Jan;4(1):49-52.
5. Lima V, Burt B, Leibovitch I, et al. Orbital compartment syndrome: the ophthalmic surgical emergency. Surv Ophthalmol. 2009;54(4):441-9.