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,12 it would be another 10 years before the instrumentation and techniques had evolved to allow broad clinical use. 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 many academic and community hospital settings.
Salivary stones occurr 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 percent in the parotid glands. Traditional therapy for those with symptomatic sialadenitis secondary to stone disease consisted of direct transoral removal of submandibular duct stones in those few stones located close to the ostium of the submandibular duct, and conservative management with sialogoges, massage, hydration and antibiotics. In persons with persistent or recurring sialadenitis secondary to inaccessible stones, transcervical excision of the involved gland was required.
Sialendoscopy has both diagnostic and therapeutic value in the management of salivary stones, strictures, and chronic sialadenitis secondary to I-131 therapy. The small caliber semi-rigid scopes employed have a working channel which allow a minimally invasive approach managing obstructive disease. The working channel can accommodate wire baskets for removal of small stones, balloons for dilation of strictures, and even laser fibers or drilling burrs. The irrigation channel allows removal of organic debris, fragments of calculi, and allows the instillation of steroids. 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 percent) whereas submandibular duct stones often require an additional transoral approach.5 This is because using endoscopy alone; stones up to 4.5 mm can be removed. 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 percent of patients receiving I-131 therapy.6 Recent case series show improvement in approximately 75 percent of persons with radioiodine-induced sialadenitis using sailendoscopic treatment options.7
A recent quality of life survey by Gillispie et al. 8 of 206 patents treated with sialendoscopic technique found that resolution of symptoms and improvements in quality of life were reported in 89%. Although persons with stone disease did the best, the majority of those with other types of obstructive salivary gland disease saw improvement with this minimally invasive technique as well.
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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 DYSalivary 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.
8 Gillespie MB, O-Connell BP, Rawl JW, McLaughlin CW, Carroll WW, Nguyen SA. Clinical and quality of life outcomes following gland-preserving surgery for chronic sialadenitis.Laryngoscope 2014 Nov 25 Epub ahead of print.