Salivary Gland Obstruction

Educational Objectives

The goals of this program are to improve diagnosis and treatment of disorders of the salivary glands. After hearing and assimilating this program, the clinician will be better able to:

1. Recognize symptoms and signs of obstruction of the salivary duct.
2. Safely relieve an obstruction of the parotid gland. 

Summary

Obstructive symptoms: include painful swelling of gland; caused by stones, Sjögren syndrome, sarcoid, sialadenosis, and radioiodine

Salivary duct scar: second most common cause of obstruction of salivary duct, after stones; ductal scar present in most patients with obstructive symptoms who have no stone on imaging; scar may be related to previous infection, stone, autoimmune or inflammatory condition, trauma, radiation, ductal reflux, congenital anomaly, or kinking of duct; scarring most common in parotid gland (75% of cases); in contrast, ≈75% of stones in submandibular gland; in parotid, scarring occurs primarily in main duct and near ostium; endoscopic treatment indicated

Anatomy: luminal diameter of Wharton duct 2.5 to 3 mm; mean diameter of Stenson duct 2 to 2.5 mm; ostium ≈0.5 mm; scarring may form band that blocks lumen; in contrast, stenosis presents as lengthwise, circumferential narrowing without loss of lumen

Symptoms: patients symptomatic when size of duct <1.6 mm; symptoms include painful swelling (typically associated with meals) and occasionally infection with fever, pain, erythema, or purulent discharge; dry mouth less common

Management: includes addressing underlying cause and reducing exposure to drying medications, caffeine, and smoking; for patient with dry mouth and eyes, unstimulated saliva collection for 15 min used to detect Sjögren syndrome; spitting <1.5 mL in 15 min indicates underproduction and should lead to serologic testing for SSA and SSB; these antibodies appear late (patients may have symptoms for 5 yr before tests become positive); biopsy of minor salivary gland should be considered if patient has dry mouth and eyes, multiglandular complaints, negative serology for Sjögren, or intraglandular nodes on ultrasonography (common finding in Sjögren syndrome)

Imaging: computed tomography can show stone but often negative in patients with scarring; ultrasonography preferred when scar suspected; study may include sialagogue challenge with sour foods; objective to localize scar; sialography or magnetic resonance (MR) sialography helpful; on ultrasonography, stenosis appears as hyperechoic structure around dilated duct with thick wall; sialography most sensitive technique for diagnosing scar; in study of >1300 sialographies, 66% of strictures at single site, 33% at multiple sites, and 7% bilateral; strictures more common in women; when sialendoscopy used to confirm stenosis, MR sialography 100% sensitive and 93% specific

Diagnostic sialendoscopy: normal tissue pink (resembling salmon) with thin vessels; scars pale and avascular; in patient with inflammatory condition, tissue erythematous with dilated vessels; clinician should examine consistency of tissue; normal duct pliable; stiffness suggests change in wall; location of scar (eg, ostium, distal or proximal main duct, hilum, or intraglandular duct) and distance from ostium should be described

Classifying findings: Cotton-Myer — scar graded based on luminal diameter using system for grading airway; stenosis of ≤50% (ability to pass 1.3-mm scope) grade I; stenosis of 50% to 70% (1.1-mm scope can pass) grade II; stenosis of 70% to 99% (0.8-mm scope can pass) grade III; complete stenosis grade IV; LSD (lithiasis, stenosis, dilatation) — S0 means no stenosis; S1 refers to ≥1 diaphragmatic stenoses; S2 means single stenosis of main duct; S3 means multiple stenoses or complete stenosis of main duct; S4 denotes intraglandular ductal stenosis and stenosis of main duct; Erlangen classification — describes nature of scar; type 1 inflammatory; type 2 weblike stenosis and segmental dilation; type 3 fibrotic, long-segment stenosis

Surgical pearls: stenoses may be dilated with tip of scope, basket, balloon, guidewire, or bougie; scar tissue often firm; speaker prefers Cook balloon, which offers high pressure and low volume but requires passage of 1.6-mm scope; for tight stricture, clinician may begin with 0.8-mm scope, then pass balloon beside scope; for complete stricture, use hand drill to make hole that can admit guidewire; malleable dilators unlikely to perforate duct, but instruments should not be advanced too far; most perforations occur at hilum; hydrostatic dilation and tip of scope or basket used for intraglandular stenosis in second- or third-order duct; in some cases, strategically placed incisions used to repair ductal pathology not amenable to endoscopic treatment; retrograde approach may be useful for stenoses of Stenson duct

Surgical approach by grade: grade I — most scopes passable; treated with serial passage of larger scopes and hydrostatic dilation; grade II — may require guidewire, malleable dilators, or balloon; grade III and IV — scar perforated with hand drill and tip of scope, then dilated with guidewire or malleable dilators; if neither scope nor wire passable, combined approach with incision needed; intraglandular stenosis — surgeon may dilate with tip of scope, hydrostatic dilation, and wire basket; when every technique fails, duct may be tied off and gland allowed to atrophy; injections of onabotulinumtoxinA may be needed

Readings

Erkul E, Gillespie MB: Sialendoscopy for non-stone disorders: The current evidence. Laryngoscope Investig Otolaryngol 2016 Sep 7;1(5):140-145; Gadodia A et al: Magnetic resonance sialography using CISS and HASTE sequences in inflammatory salivary gland diseases: comparison with digital sialography. Acta Radiol 2010 Mar;51(2):156-63; Koch M et al: Sialendoscopy-based diagnosis and classification of parotid duct stenoses. Laryngoscope 2009 Sep;119(9):1696-703; Marchal F et al: Salivary stones and stenosis. A comprehensive classification. Rev Stomatol Chir Maxillofac 2008 Sep;109(4):233-6; Ngu RK et al: Salivary duct strictures: nature and incidence in benign salivary obstruction. Dentomaxillofac Radiol 2007 Feb;36(2):63-7.

Disclosures

For this program, members of the faculty and planning committee reported nothing to disclose.

Acknowledgements

Dr. Gillespie was recorded at Sialendoscopy and Salivary Duct Surgery Course, presented by University of California, San Francisco, School of Medicine and held November 17, 2016, in San Francisco, CA. To learn about upcoming CME opportunities from the University of California, San Francisco, School of Medicine, please go to meded.ucsf.edu/cme. The Audio Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

OT510101

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.