Sialendoscopy for Salivary Stones
Sialendoscopy has emerged as an effective and minimally invasive treatment for management of salivary stones and strictures of the parotid and submandibular salivary glands. Although initial efforts to remove salivary stones endoscopically date back to the early 1990s,1,2 it would be another 10 years before the instrumentation and techniques had evolved to allow broad clinical use. This is primarily due to the very small caliber of the salivary ducts. The use of sialendoscopy first became popular in Europe and in recent years has become increasingly available in the United States. Only several years ago, the technique was offered in a minority of academic centers. Now sialendoscopy and related techniques are available in most academic and in some community hospital settings.
Salivary stone occurrence and management
Salivary stones are relatively common, occurring in slightly over 1% of individuals on post-mortem studies.3 However, the percentage of individuals who are symptomatic and require treatment is much lower at 1/20,000.4 Eighty percent of symptomatic stones occur in the submandibular glands and the remaining 20% in the parotid glands. Patients with symptomatic stones have pain and swelling of the affected gland typically with meals. Many are also prone to intermittent infectious sialadenitis. Traditional therapy consisted of direct transoral removal of submandibular duct stones in those few stones located close to the ostium of the submandibular duct. Conservative management with sialogoges, massage, hydration and antibiotics for infections was the only non-invasive therapy possible. In persons with persistent problems who had stones of the parotid duct or stones located further away from the ostium of the submandibular duct, transcervical excision of the gland was required. Apart from the necessary external cervical scar, these transcervical procedures were associated with risks including permanent weakness of the facial nerve branches in 5-10% of persons and a 2-3% injury to the lingual nerve supplying sensation to the tongue.
When to consider sialendoscopy
Sialendoscopy offers us the ability to remove stones of either the submandibular or parotid glands transorally. With these techniques small stones can be extracted through the scopes alone and larger stone removal is now possible transorally using the sialendoscopes for localization. Most parotid stones can be extracted with sialendoscopy alone (80%) whereas submandibular duct stones often require an additional transoral approach.5 This is because stones up to 4.5 mm can be removed using endoscopy alone. Stones of the parotid duct are typically smaller than those of the submandibular duct, and submandibular duct stones are more adherent to the surrounding duct lining.
Sialendoscopy has also become very helpful in managing sialadenitis secondary to stricture or radioactive iodine (I-131) therapy. Chronic sialadenitis secondary to prior I-131 has been found in approximately 20% of patients receiving I-131 therapy.6 Recent case series show improvement in approximately 75% of persons with radioiodine-induced sialadenitis using sailendoscopic treatment options.7
For more information
Sialendoscopy and other minimally invasive techniques are available for managing salivary gland disease such as stones, strictures and tumors. Read about UW Health’s Otolaryngology services online, or make a referral with any of our dedicated head and neck surgeons by contacting the Otolaryngology Clinic at (608) 263-6190.
1 Katz P. A new method of exploration of the salivary glands: the fiberscope. Inf Dent 1990;72:785-786
2 Gundlach P, Hopf J, Linnarz M. Introduction of a new diagnostic procedure: salivary duct endoscopy clinical evaluation of sialendoscopy, sailography, and x-ray imaging. Endosc Surg Allied Technol 1994;2:294-6
3 Capaccio P, Clemente IA, McGurk M, Bossi A, Pignataro L. Transoral removal of hiloparenchymal submandibular calculi: a long-term clinical experience. Eur Arch Otorhinolaryngol. 2011;268:1081-1086
4 Rauch S, Gorlin RJ. Diseases of the salivary glands. In: GorlinRJ, GoldmanHM , eds. Oral Pathology. 6th ed.St Louis, MO: Mosby; 1970:997-1003.
5 Zenk J, Koch M, Klitworth N, Konig B, Konz K, Gillespie M, Iro H. Sialendoscopy in the diagnosis and treatment of sialolithiasis: a study on more than 1000 patients. Otolaryngol Hea Neck Surg 2012 Nov;147(5):858-63.
6 Lee HN, An JY, Lee KM, Choi WS, Kim DY. Salivary gland dysfunction after radioactive iodine (I-131) therapy in patients following total thyroidectomy: emphasis on radioactive iodine therapy dose. Clin Imaging 2015 Jan 7. (14): 324-6
7 Bomeli SR, Schaitkin B, Carrau RL, Walvekar RR. Interventional sialendoscopy for treatment of radioiodine-induced sialadenitis. Laryngoscope. 2009 May;119(5):864-7.