Case Reports

A Rare Case of Traumatic Tension Pneumo-orbitum

Emergency Medicine. 2016 August;48(8):357-361 | 10.12788/emed.2016.0050

References

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4. Roberts JR, Hedges JR (eds). Clinical Procedures in Emergency Medicine, 4th ed. Philadelphia, PA: Saunders; 2004.

5. Hatton MP, Thakker MM, Ray S. Orbital and adnexal trauma associated with open-globe injuries. Ophthal Plast Reconstr Surg. 2002;18(6):458-461.

6. Suner S, Simmons W, Savitt DL. A porcine model for instruction of lateral canthotomy. Acad Emerg Med. 2000;7(7):837-838.

7. Goodall KL, Brahma A, Bates A, Leatherbarrow B. Lateral canthotomy and inferior cantholysis: an effective method of urgent orbital decompression for sight threatening acute retrobulbar hemorrhage. Injury. 1999;30(7):485-490.

8. Gerbino G, Ramieri GA, Nasi A. Diagnosis and treatment of retrobulbar haematomas following blunt orbital trauma: a description of eight cases. Int J Oral Maxillofac Surg. 2005;34(2):127-131.

9. Machado RA, Silveira RL, Borges HO, Filho AM, de Oliveira GM. Retrobulbar hemorrhage: A case report. J Contemp Dent Pract. 2006;7(2):130-136.

10. Winans JM, House LR, Robinson HE. Self-induced orbital emphysema as a presenting sign of Munchausen’s syndrome. Laryngoscope. 1983;93(9):1209-1211.

11. Zimmer-Galler IE, Bartley GB. Orbital emphysema: case reports and review of the literature. Mayo Clin Proc. 1994;69(2):115-121.

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Lateral Canthotomy

Although EPs rarely perform lateral canthotomy, knowledge of this procedure is important, because it can prevent vision loss in the appropriate clinical setting. To perform a lateral canthotomy, the area around the affected eye is cleaned with saline irrigation.⁴ One percent or 2% lidocaine with epinephrine is then injected into the lateral canthus of the affected eye.^4,10 A straight hemostat is applied between the upper and lower lids, producing a crush injury along the site of local anesthesia for 1 to 2 minutes.^3,4,10 This is done to reduce the risk of bleeding by devitalizing the tissue.⁴ Straight scissors are then used to make a 1-cm horizontal incision from the lateral canthal tendon to the lateral orbital rim.⁴ This initial incision exposes the orbicularis muscle, orbital septum, palpebral conjunctiva, and an area called Eisler’s pocket that sits anterior to the lateral canthal tendon.³

Cantholysis can then be performed by blunt dissection.¹⁰ The inferior crus of the lateral canthus is identified either visually or by palpation, and a 1- to 2-cm inferior-posterior cut of the inferior crus accomplishes the lateral canthotomy.^3-4 After cutting the inferior crus, the lower lid should be pulled away easily, and if this does not occur, repeated attempts at cutting the inferior crus should be made.³ Pulling the lower eyelid down and away from the lateral orbital rim separates the skin and conjunctiva, aiding in visualization.⁴

After cutting the inferior crus, only a small amount of blood or air typically is expressed, but this is usually enough to prevent vision loss.³ When the procedure is performed correctly, the practitioner should be able to palpate a difference in the pressure of the globe, and tonography will show a reduced IOP. If the ocular pressure is still significantly elevated, the physician can proceed to cut the superior canthus of the lateral canthal tendon in a manner similar to cutting the inferior crus of the tendon.⁴ After the procedure is performed, urgent ophthalmologic consultation is required.

The risks of performing a lateral canthotomy include mechanical injury, hemorrhage, and infection.⁴ The incision from a lateral canthotomy generally does not need suturing and will heal without significant scarring.⁴ If the scissors are aimed superiorly instead of inferiorly for the inferior crus of the lateral canthal tendon, there is risk of injuring the levator aponeurosis leading to ptosis, as well as a small risk of injury to the lacrimal gland and lacrimal artery.³

Conclusion

Our patient demonstrates a case of traumatic OCS, a vision-threatening medical condition that requires rapid diagnosis and lateral canthotomy to lower IOP and reduce the risk of permanent vision loss. While an orbital CT scan may assist in confirming the diagnosis, treatment of IOP should not be delayed.