Salivary Mucocele Excision: Proceed with Caution

Definitive treatment of salivary mucoceles involves surgical excision of the gland and associated ducts; percutaneous drainage remains a temporary palliative option with low potential for success. The conventional described lateral surgical approach can potentially leave residual glandular tissue from the polystomatic portion of the sublingual gland. An alternative technique has been proposed to offer more complete excision. This cadaveric study compared traditional lateral approach to tunneling under the digastricus muscle in dogs, which was accomplished through a more laterally located skin incision following the angle of the mandible, then passing an instrument medial to the digastric muscle to grasp the duct for a more rostral transection. The median additional salivary duct length gain was 1.8 cm; this did not vary based on duct side or patient weight. Residual glandular tissue remained in only 2/15 tunneling procedures, compared with 100% of specimens using the conventional approach.

Commentary

Surgical excision of salivary mucoceles is complicated by local vital structures of the ventral cervical region, sometimes obscured by massive saliva accumulation and associated tissue reaction. Long-term success is related to complete excision of all secretory glandular tissue. The mandibular and monostomatic portion of the sublingual salivary glands are easily identified, but the polystomatic portion of the sublingual gland extends a variable distance rostral along the secretory duct and may be responsible for recurrence. Although based on an ex-vivo model in dogs with normal salivary tissue, results suggested that the traditional approach results in inadequate excision. Alternatives include transection of or tunneling under the digastricus muscle. However, a detailed understanding of the local neurovascular anatomy and delicate dissection skills are essential to success.—Jason Bleedorn, DVM, DACVS

Source

Tunneling under the digastricus muscle increases salivary duct exposure and completeness of excision in mandibular and sublingual sialoadenectomy in dogs. Marsh A, Adin C. VET SURG 42:238-242, 2013.