Ultrasound-guided injection of the maxillary nerve in the horse.
Abstract: Infiltration of the equine maxillary nerve with local anaesthetic can be useful for both diagnostic and surgical procedures. The deep location and proximity of the nerve to surrounding vascular and orbital structures make an accurate, complication-free injection a challenge using traditional techniques reliant upon surface anatomical landmarks. Objective: To develop an ultrasound-guided injection technique of the maxillary nerve in equine cadavers and to evaluate its efficacy and potential for complications in vivo. Methods: Descriptive cadaver anatomical and clinical study. Methods: The relevant anatomy of the pterygopalatine fossa was reviewed in 6 cadaver heads from mature horses of a range of ages, breeds and genders. In an additional 13 cadaver heads, ultrasound-guided injection of 0.2 ml New Methylene Blue dye was performed on both left and right maxillary nerves (n = 26 attempts) in the pterygopalatine fossa. An independent observer dissected the area and recorded the number of times that dye successfully contacted the nerve, along with inadvertent penetration of other structures. The procedure was then performed on 8 clinical cases undergoing a variety of standing surgical procedures on the head. Results: Dye was successfully deposited in contact with the nerve during all attempts on cadaver heads, with no penetration of the orbital cone, deep facial vein and maxillary artery or associated branches. In a single cadaver, a unilateral gas artefact in the masseter muscle prohibited an injection attempt. Analgesia of the maxillary nerve was achieved in <15 min in all clinical cases, with complete loss of ipsilateral cutaneous sensation over the rostral face. No gross or ultrasonographic abnormalities were detected following the procedure. Conclusions: Using ultrasonographic landmarks of the pterygopalatine fossa, local anaesthetic can be deposited around the maxillary nerve without the inadvertent penetration of adjacent vital structures. Conclusions: The technique allows for vascular structures to be visualised and avoided, which is currently not possible using traditional blind approaches.
© 2013 EVJ Ltd.
Publication Date: 2013-08-30 PubMed ID: 23679076DOI: 10.1111/evj.12106Google Scholar: Lookup
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- Journal Article
Summary
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This research article presents a study on the use of ultrasound-guided injections to administer local anaesthetic to the maxillary nerve in horses. The study found that using ultrasound to guide the injection allowed for a more accurate deposition of the anaesthetic, which avoided inadvertent penetration into the surrounding vascular and orbital structures.
Research Goals and Methods
- The primary aim of this research was to develop an ultrasound-guided injection technique for the maxillary nerve in horses and to assess its effectiveness and potential for complications in live animals.
- The researchers initially studied the relevant anatomy of the pterygopalatine fossa in 6 equine cadaver heads from a diverse range of ages, breeds, and genders.
- In 13 additional cadaver heads, the researchers used ultrasound guidance to inject a dye into the maxillary nerve. An independent observer dissected the nerve area after injection to record the number of successful dye contacts and any inadvertent penetration of other structures.
- The procedure was later implemented on 8 horses undergoing various standing surgical procedures on the head.
Findings and Results
- The dye was successfully deposited in contact with the nerve in every cadaver trial, without any inadvertent penetration into adjacent vital structures such as the orbital cone, deep facial vein, and maxillary artery or its branches.
- In one cadaver, an injection attempt was not made due to a unilateral gas artefact in the masseter muscle.
- In the live case studies, the maxillary nerve was anesthetized in under 15 minutes in all cases. Complete loss of sensation on the corresponding side of the face was observed.
- No gross or ultrasonographic abnormalities were reported following the procedure.
Conclusions
- The researchers concluded that using ultrasonographic landmarks of the pterygopalatine fossa, local anaesthetic could be deposited around the maxillary nerve without causing inadvertent penetration into adjacent structures.
- This new approach makes it possible to visualize and avoid impacting vascular structures, which is not currently possible when using traditional blind injection techniques.
Cite This Article
APA
O'Neill HD, Garcia-Pereira FL, Mohankumar PS.
(2013).
Ultrasound-guided injection of the maxillary nerve in the horse.
Equine Vet J, 46(2), 180-184.
https://doi.org/10.1111/evj.12106 Publication
Researcher Affiliations
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, USA.
MeSH Terms
- Anesthesia, Local / methods
- Anesthesia, Local / veterinary
- Animals
- Cadaver
- Horses / anatomy & histology
- Injections / methods
- Injections / veterinary
- Maxillary Nerve / anatomy & histology
- Methylene Blue / analogs & derivatives
- Nerve Block / methods
- Nerve Block / veterinary
- Ultrasonography / veterinary
Citations
This article has been cited 9 times.- Vuerich M, Nannarone S. Retrograde Approach to Maxillary Nerve Block: An Alternative in Orofacial Surgeries in Horses. Animals (Basel) 2022 May 27;12(11).
- Hermans H, Lloyd-Edwards RA, Ferrão-van Sommeren AJH, Tersmette AA, Schouten JCM, Serra Bragança FM, van Loon JPAM. Comparing Blind and Ultrasound-Guided Retrobulbar Nerve Blocks in Equine Cadavers: The Training Effect. Animals (Basel) 2022 Jan 9;12(2).
- Johnson JP, Vinardell T, David F. Ultrasound-guided injections of the equine head and neck: review and expert opinion. J Equine Sci 2021 Dec;32(4):103-115.
- Pezzanite LM, Hackett ES, McCready E, Easley JT. Outcomes following single, caudally based bilateral versus unilateral frontonasal sinusotomy for treatment of equine paranasal sinus disease. Vet Med Sci 2021 Nov;7(6):2209-2218.
- Shilo-Benjamini Y, Letz S, Peery D, Abu Ahmad W, Bar-Am Y. Comparison of three regional anaesthetic techniques for infraorbital or maxillary nerve block in cats: a cadaveric study. J Feline Med Surg 2022 Apr;24(4):322-327.
- Leigh H, Gozalo-Marcilla M, Esteve V, Gutiérrez Bautista ÁJ, Martin Gimenez T, Viscasillas J. Description of a novel ultrasound guided peribulbar block in horses: a cadaveric study. J Vet Sci 2021 Mar;22(2):e22.
- Bell C, Hnenny L, Torske K. Internal neurolysis of the maxillary branch of the trigeminal nerve for the treatment of equine trigeminal mediated headshaking syndrome. Can Vet J 2018 Jul;59(7):763-769.
- Woodman MJ, MacKenzie J, Osinchuk S, Husulak M. Severe orbital hematoma with third eyelid swelling and prolapse following a blind maxillary nerve block in a horse. Can Vet J 2024 Apr;65(4):359-362.
- McAndrews A, Zarucco L, Hopster K, Stefanovski D, Foster D, Driessen B. Evaluation of Three Methods of Sensory Function Testing for the Assessment of Successful Maxillary Nerve Blockade in Horses. J Vet Dent 2025 Jan;42(1):48-54.
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