A transorbital approach to the maxillary nerve block in dogs: a cadaver study

This is the author accepted manuscript. The final version is available from Elsevier via https://doi.org/10.1111/vaa.12381Objective: To describe a transorbital approach to the maxillary nerve block in dogs and compare it to a traditional one. Study Design: Prospective, randomised controlled study. Animals: Heads from 17 euthanized dogs (10 greyhounds, 3 border collies and 4 mixed breed). Methods: A volume of 1 mL of methylene blue dye was injected by each of two techniques, a traditional percutaneous and a transorbital approach to the maxillary nerve block. Both techniques were used on each head with left and right sides alternating following random assignment to the first head. The heads were dissected to reveal the maxillary nerve and the length of nerve stained was measured. Results: There was no significant difference (p = 0.67) in the proportion of nerves stained greater than 6 mm by either technique (88.2% transorbital, 82.3% percutaneous). The mean length of nerve stained did not differ significantly between the techniques (p = 0.26). Conclusions and clinical relevance: The transorbital approach to the maxillary nerve block described here presents a viable alternative to the traditional percutaneous approach. Further study is required to confirm efficacy and safety under clinical conditions