Assesment of gland function with sialo-scintigrapy following sialolithectomy for calculi in posterior submandibular duct

Controversy continued as to surgical treatment of a sialolith located close to the submandibular gland, the opinions being excision of the submandibular gland and transoral removal of the stone.To determine the extent of grandular recovery, we examined the submandibular gland function with 99mTc-pertechnetate sialo-scintigraphy following sailolithectomy or spontaneous excretion in four cases of sialolithiasis in which the stone was located on the posterior submandibular duct. An intraindividual comparison of the function of the treated gland with that of the contralateral normal gland was made by time-activity curve from regions of interest over both submadibular glands.In two cases the function of surgically treated submandibuar gland was restored to the same condition as that of the contralateral normal gland at more than two months later after the removal of the stone. In the other two cases submandibular gland was firm on palpation and extensive inflammation was noted showing pus secretion from the orifice of Wharton's duct at first visit. Salivary excrete function on the sialo-scintigraphy was not seen soon after removal of the stone. More than three months later, however, it recovered to about 60% of contralateral normal gland associated with a production of clear saliva from treated submandibular gland.These results suggested that functional recovery may be expectd to some extent in a submandibular gland strikingly damaged by sialolithiasis, and that transoral removal is a valid treatment for a stone located close to the submandibular gland.