2.1.1 Therapeutic sialendoscopy is used in the treatment of suspected salivary gland obstruction. Obstruction of the ducts is most commonly caused by sialolithiasis (stones).
2.1.2 Symptoms of salivary gland obstruction are varied and include swelling of the face or neck, swelling in front of the ear, pain in the face or mouth and decreased ability to open the mouth.
2.1.3 Treatment of salivary gland obstruction depends on the underlying cause and location. For most benign ductal disorders such as sialolithiasis treatment includes surgical excision of the stone from within the mouth if it is easily accessible. Interventional sialography and extracorporeal or endoscopic lithotripsy may also be used. Removal of the affected salivary gland may be required for large or less accessible stones.
2.2.1 The procedure is typically performed under local anaesthesia. Progressive dilatation of the salivary duct, with or without stents, is performed until the opening is large enough to allow the introduction of an endoscope. The duct is irrigated initially with a local anaesthetic solution and then with saline as the scope is passed through the ductal system. Instruments (such as wire retrieval baskets) are then introduced through the endoscope to remove stones. A stent may sometimes be left in the duct postoperatively.
2.3.1 The evidence of efficacy was based on five case series. Across these studies therapeutic sialendoscopy relieved duct obstruction in between 82% (90/110) and 87% (47/54) of cases.
2.3.2 In a study of 72 patients, 8% (6/72) had continuing symptoms or other clinical problems which did not improve after the procedure and required removal of the gland (sialadenectomy). In another study of 129 patients, 110 of whom underwent therapeutic sialendoscopy, the treatment was considered a failure in 18% (20/110) of patients, 5 of whom required gland removal.
2.3.3 Recurrence of obstructive symptoms was reported in two of the studies, with rates of 2% (4/236) and 5% (3/55), respectively. All recurrences occurred between 15 and 24 months after the procedure. For more details, refer to the 'Sources of evidence' section.
2.3.4 The Specialist Advisers did not consider there to be any uncertainties about this procedure. One Adviser noted that high success rates are reported in the published literature.
2.4.1 Few complications were reported in the five case series reviewed. Temporary swelling of the gland was common. In one study of 129 patients, ductal wall perforation occurred in 11 patients (9%), with two of these patients requiring hospitalisation and one patient undergoing gland resection. Three other studies reported cases of salivary gland perforation with an incidence of between < 1% and 5% (3/55, 1/103, 1/236). One patient (1/236) developed lingual nerve paraesthesia caused by the perforation. Ductal strictures were also reported in seven patients (3%) in a case series of 236 patients. Five patients underwent successful dilatation but two required open surgery. Other complications included difficulty in retrieving the wire basket after engaging the stone and postoperative infections. For more details, refer to the 'Sources of evidence' section.
2.4.2 The Specialist Advisers stated the potential complications include infection, perforation of the duct, ranula formation, lingual nerve injury and duct stenosis.