A dissection of the larynges of 7 mature dogs was performed and the existence of anastomotic branches between the bilateral laryngeal nerves was histologically confirmed. The motor nerve branches were found to make an anastomosis in all of the 7 dogs. In 2 of the 7 dogs, the sensory branches were also found to make an anastomosis, while this was not confirmed in the remaining 5-possibly due to technical failures. The branches of the recurrent laryngeal nerve to the arytenoid (transversus) muscle were found to ramify into two smaller branches just before its entrance to the muscle. One of the two smaller branches made an anastomosis with the corresponding branch of the opposite side beneath the lower margin of the arytenoid muscle. This seemed to be a motor anastomosis. Accordingly, the arytenoid muscle appeared to be supplied not only from the branch of the recurrent laryngeal nerve directly, but also via the anastomosis. The sensory nerve anastomosis appeared to be derived from the bilateral Galen's loop at the level of the posterior upper margin of the cricoid cartilage. The motor and sensory anastomoses described above have not been reported in the previous literature.
