Lateral Canthotomy

Indications (Retrobulbar Hematoma)

1. decreased VA

2. elevated IOP >40 mmHg

3. afferent pupillary defect (APD): shine light on affected eye, dilated ipsilateral and contralateral pupil

4. severe proptosis

also

5. cherry red macula

6. ophthalmoplegia

7. nerve head pallor

8. eye pain

Contraindications

Globe rupture

- signs of occult Globe rupture

Procedure

1. 1-2 cc of lidocaine with epi into lateral canthus

2. Crush lateral canthus with hemostat for 30-90 seconds

3. Incise lateral canthus 1-2 cm with iris scissors

4. Pull lower lid inferiorly, using tip of iris' cut inferior canthal ligament

5. Reassess IOP: if >40mmHg, cut superior canthal ligament

Notes:

1. Retrobulbar hematoma: Compartment syndrome of the eye

2. Time is vision: 120 minutes before vision is lost

3. Despite high pressure, small amount of blood when released

4. Blind procedure: feel the guitar string

5. When cutting, aim inferoposteriorly toward lateral rim