Canthotomy(also calledlateral canthotomyandcanthotomy with cantholysis) is a surgical procedure where the lateralcanthus,or corner, of theeyeis cut to relieve thefluid pressureinside or behind the eye, known asintraocular pressure(IOC).[1]The procedure is typically done in emergency situations when the intraocular pressure becomes too high, which can damage theoptic nerveand lead to blindness if left untreated.[2]
| Canthotomy | |
|---|---|
 Eye anatomy demonstrating the medial canthus | |
| Pronunciation | kăn-thŏt′ə-mē |
| Other names | Lateral canthotomy, canthotomy with cantholysis |
| Specialty | Ophthalmologyandemergency medicine |
| Complications | Iatrogenic globe injury, bleeding, infection |
The most common cause of elevated intraocular pressure is orbitalcompartment syndrome(OCS) caused by trauma,retrobulbar hemorrhage,infections, tumors, or prolongedhypoxemia.[3]Absolute contraindicationsto canthotomy includeglobe rupture.Complications include bleeding, infections, cosmetic deformities, and functional impairment of eyelids.[3]Lateral canthotomy further specifies that the lateral canthus is being cut. Canthotomy with cantholysis includes cutting thelateral palpebral ligament,also known as the canthal tendon.
History
editThe first case of orbital compartment syndrome causing monocular blindness was published in 1950 due to a complication of azygomatic fracturerepair.[4]In 1953, the first surgical orbital decompression was performed. Two incisions below and above the external canthus were made andsurgical drainswere put in place.[5]In 1990, the first lateral canthotomy procedure as presently performed was completed.[6]In 1994, lateral canthotomy was first published in a review of procedures that emergency physicians can perform.[7]Today, a canthotomy is almost always performed with cantholysis of the inferior canthal tendon as this provides the best decompression of intraocular pressure.[8]
Indications
editA canthotomy is often used as a last resort to decompress orbital compartment syndrome. Orbital compartment syndrome can be caused by trauma, infections, tumors, retrobulbar hemorrhage, or prolonged hypoxemia.[9]Orbital compartment syndrome can be recognized by elevated intraocular pressure, globe compressibility,afferent pupillary defect,proptosis,decreased visual acuity, and decreasedextraocular musclemovements.
Studies in animals have demonstrated irreversible vision loss within 90 to 120 minutes, further indicating the emergent nature of this procedure.[8]
In an unconscious patient who is unable to comply with a physical exam, an intraocular pressure greater than 40 indicates emergent canthotomy.[2]
Contraindications
edit
The foremost absolute contraindication to canthotomy isglobe rupture,sometimes referred to as an open globe injury.[9]Globe rupture can be recognized by these symptoms or physical exam features:
- Irregular-shapedpupiloriris
- Subconjunctival hemorrhage
- Enophthalmos
- Conjunctival or scleral tear
Due to the emergent nature of this procedure and the possibility of restoring or preventing vision loss, globe rupture is the only absolute contraindication.
Complications
edit
Due to portions of the procedure having poor visualization of anatomical structures, and the overall rarity and difficulty of the procedure,iatrogenicglobe injury is an immediate complication that can occur. Other complications include infections, bleeding, cosmetic deformities, and functional impairment of eyelids.[3]
Alternatives
editDue to the infrequency and difficulty of canthotomy,emergency medicine physiciansdefer more than 50 percent of canthotomies to a consulting physician,[10]which in turn can increase time to treatment. In an effort to decrease difficulty and improve patient outcomes, vertical lid split or paracanthal "one-snip" procedures have been studied. This is performed by making a full-thickness vertical incision a few millimeters medial from the lateral canthus in both the upper and lower eyelids.[11]
References
edit- ^Nagelhout, John J.; Plaus, Karen (2009). "Chapter 40. Anesthesia For Ophthalmic Procedures".Nurse Anesthesia.Elsevier Health Sciences. p.963.ISBN9780323081016.RetrievedMarch 24,2023– viaGoogle Books.
Canthotomy is a procedure performed to increase the orbital space by cutting the lateral canthus. This procedure reduces the orbital pressure that results from a retrobulbar hemorrhage.
- ^abMcInnes, Gord; Howes, Daniel W. (January 2002)."Lateral canthotomy and cantholysis: a simple, vision-saving procedure".CJEM.4(1): 49–52.doi:10.1017/s1481803500006060.ISSN1481-8035.PMID17637149.
- ^abcRowh, Adam D.; Ufberg, Jacob W.; Chan, Theodore C.; Vilke, Gary M.; Harrigan, Richard A. (March 2015)."Lateral canthotomy and cantholysis: emergency management of orbital compartment syndrome".The Journal of Emergency Medicine.48(3): 325–330.doi:10.1016/j.jemermed.2014.11.002.ISSN0736-4679.PMID25524455.
- ^Gordon, Stuart; Macrae, Harry (September 1950)."Monocular Blindness as a Complication of the Treatment of a Malar Fracture".Plastic and Reconstructive Surgery.6(3): 228–232.doi:10.1097/00006534-195009000-00005.ISSN0032-1052.PMID14780862.
- ^Penn, Jack; Epstein, Edward (January 1, 1953)."Complication following late manipulation of impacted fracture of the malar bone".British Journal of Plastic Surgery.6:65.doi:10.1016/S0007-1226(53)80009-3.ISSN0007-1226.
- ^Thompson, R.F., Gluckman, J.L., Kulwin, D. and Savoury, L. (1990), Orbital hemorrhage during ethmoid sinus surgery. Otolaryngology–Head and Neck Surgery, 102: 45-50.doi:10.1177/019459989010200108
- ^Knoop, K. and Trott, A. (1994), Ophthalmologic Procedures in the Emergency Department—Part I: Immediate Sight-saving Procedures. Academic Emergency Medicine, 1: 408-411.doi:10.1111/j.1553-2712.1994.tb02657.x
- ^abHaubner, Frank; Jägle, Herbert; Nunes, Diogo Pereira; Schleder, Stephan; Cvetkova, Nadezha; Kühnel, Thomas; Gassner, Holger G. (February 2015)."Orbital compartment: effects of emergent canthotomy and cantholysis".European Archives of Oto-Rhino-Laryngology.272(2): 479–483.doi:10.1007/s00405-014-3238-5.ISSN0937-4477.PMID25115315.
- ^abDesai, Ninad M.; Shah, Sumir u (2022),"Lateral Orbital Canthotomy",StatPearls,Treasure Island (FL): StatPearls Publishing,PMID32491408,retrievedMarch 10,2023
- ^Yarter, Jason T.; Racht, Justin; Michels, Kevin S. (February 2023)."Retrobulbar hemorrhage decompression with paracanthal" one-snip "method: Time to retire lateral canthotomy?".The American Journal of Emergency Medicine.64:206.e1–206.e3.doi:10.1016/j.ajem.2022.11.027.ISSN1532-8171.PMID36564334.
- ^Elpers, Julia; Areephanthu, Christopher; Timoney, Peter J.; Nunery, William R.; Lee, H.B. Harold; Fu, Roxana (May 4, 2021)."Efficacy of vertical lid split versus lateral canthotomy and cantholysis in the management of orbital compartment syndrome".Orbit.40(3): 222–227.doi:10.1080/01676830.2020.1767154.ISSN0167-6830.PMID32460574.
Further reading
edit- Brady, C. J. (2023, February 14). "How to do lateral canthotomy - eye disorders".Merck Manuals Professional Edition.Retrieved March 11, 2023, fromhttps:// merckmanuals /professional/eye-disorders/how-to-do-eye-procedures/how-to-do-lateral-canthotomy
- Chapter 162. "Lateral canthotomy and cantholysis or acute orbital compartment syndrome management". Reichman E.F.(Ed.), (2013).Emergency Medicine Procedures, 2e.McGraw Hill.https://accessemergencymedicine.mhmedical /content.aspx?bookid=683§ionid=45343809
- Lem M, Oyur KB, Labove G, Hoang-Tran C, Bhola R, Pfaff MJ. "Lateral Canthotomy and Cantholysis for Spontaneous Retrobulbar Hemorrhage With Normal Intraocular Pressures: Case Report and Review of the Literature".FACE.2022;3(4):536-539.doi:10.1177/27325016221128771