return to: Salivary Swelling; Salivary Gland Surgery Protocols; Salivary Ultrasound

see also: Combined Open and Endoscopic Removal of Parotid Stone (sialendoscopy case example) and Salivary Stone Removal with Ductoplasty from Submandibular Gland

video (with spoken audio) of procedures: Sialendoscopy with Stone Removal HOW I DO IT

GENERAL CONSIDERATIONS

• Definition: Sialolithiasis = "Salivary stone" (see also: Salivary Swelling)
  • Sialolith (stone) composed of variable amounts of organic cellular debris, glycoproteins, and mucopolysaccharides.
  • Sialoliths (stone) also composed of variable amounts of inorganic materials calcium, magnesium, manganese, copper, iron and phosphate.
• Prevalence / Incidence
  • Estimated 1% of the population are affected (autopsy studies) (Williams1999)
  • Incidence of 1 per 15,000 to 30,000 based on hospital admission statistics in England (Escudier 1999)
  • Incidence of 1 per 10,000 to 20,000 by personal observation by Dr. Marchal (Marchal 2003)
  • Calcifications identified by CT imaging of the parotid glands that occur in the parenchyma and are not associated with sialadenitis are not considered 'sialoliths'
    • Buch et al (2014) identified 4% of patients had incidental parotid calcifications through review of non-contrast head CT scans done on 1,571 patients for reasons other than sialadentitis 
    • Associated with the presence of calcifications were: HIV, alcoholism, chronic kidney disease, autoimmune disease and elevated alkaline phosphatase

• Etiology - What Causes Them: Multiple Factors Considered

  • A primary process reported for parotid stones is a decrease in the salivary secretion, both volume and flow rate (Motamed 2003) due to
    • Obstruction: strictures of the duct or, external pressure on the main duct (tumor), mucus plugging, and congenital abnormalities of the duct.
    • Other: Radiation damage and immune-mediated diseases.
  • A decrease in salivary secretion results in stasis; with retrograde bacterial contamination of the ductal system.
    • Bacterial infection may lead to destruction and fibrosis of gland architecture of acinar elements and ductal ectasia.
      • Acute suppurative sialadenitis - singular acute event may precipitate others or progress to chronic sialadenitis 
      • Chronic sialadenitis is more common and often progressive
      • Sialolithiasis is both a cause and a consequence of chronic recurring sialadenitis (Travis 1977)
  • PCR study found bacterial DNA of Streptococcus genus in all examined sialoliths (Teymoortash 2002)
  • Electron microscopy identified "clear evidence of biofilm caves at the core" of each stone studied supporting a microbial etiology (acknowledging the etiology to be most likely multifactorial) (Kao 2020) 
• Epidemiology studies
  • Tobacco smoking only positive correlation in study of nutritional habits and other behaviors (Marchal 2003)
  • No link between hypercalcemia or ingestion of hard water (Marchal 2003)
  • Katz et al (Katz 2009) suggested a genetic predisposition to form stones with 'over 300 families identified".
    • These investigators identified that in over 3500 cases of salivary lithiasis over a 20 year period, they did not identify cases wtih both submandibular and parotid stones (only one type of gland involved) - further identifying that submandidbular and parotid stones ahve the same composition but different proportions of calicum and phosphate.
• Diagnosis
  • History of recurrent painful parotid swelling
  • Physical exam: swollen gland, palpable stone, massage of gland to produce saliva.
  • Consider blood studies to evaluate auto-immune evaluation: rheumatoid factor, ANA, SS-A, SS-B antibodies.
  • Radiographic imaging (see: Sialograms and Sialography )
    • Ultrasound: advantages - potential for concurrent U/S guided FNA; absence of radiation exposure; inexpensive
    • MRI: advantages: best study for anatomic definition of salivary glands for tumor, absence of radiation exposure; evolving technology permits 'MRI sialogram"
    • CT: controversy w or w/o contrast - currently at UIHC: employ contrast; best for defining lymphadenopathy (see: Sialolithiasis Radiology)
      • Phleboliths may be misinterpreted as sialoliths; sialendoscopy or sialogram will resolve (Su 2009a)
    • Sialogram: useful to identify stones - best definition of intraductal architecture; occasionally proves therapeutic as well as diagnostic (duct dilation, 'flushing out gland') (Gerry RG 1955)
  • Sialendoscopy

MANAGEMENT 

• Conservative management: 
  • Antibiotics / analgesics / mouthwashes / sialogogues / massaging the gland
  • Antibiotic options cover staph aureus: Augmentin, clindamycin (Motamed 2003)
• Failing conservative management:
  • Decision to intervene surgically is dependent on the requests of an informed patient and the clinicians successful correlation of symptoms with the pathologic process of sialectasis.
    • Facial pain in the absence of classic swelling associated with meals may be caused by processes other than salivary disorders.
  •   Counsel re:
    • Gland removal as a a definitive invasive but usually (not always) successful approach with an emphasis on alternatives
      • Parotidectomy / Sjogren's Syndrome ( Sjögrens ) with Sialolithiasis Treated with Bilateral Parotidectomy 
      • Submandibular Gland Resection
        • see also: Case Example 2 Retrograde Sialendoscopy to Prevent Retained Ductal Stone with Submandibular Gland Resection
        • see also: Case Example Retained Submandibular Stone After Submandibular Gland Resection with neck fistula
    • Sialendoscopy with laser fragmentation and basket removal -
      • Small stones (< 3 mm) reported 97% success rate with wire basket removal w/o fragmentation (Marchal 2001)
      • Larger stones (> 3 mm) reported 35% success with wire basket removal w/o fragmentation; increases to 72% with fragmentation; unusual to approach larger stones without attempted laser fragmentation
      • Extracorporeal Lithotripsy
        • Available in Germany and other sites in Europe but not in the United States- external lithotripsy may permit spontaneous extrusion of fragmented parotid stones in 40% of cases
        • Often done along with sialendoscopy to assist in removal of stone fragments (Luers 2009)
      • Pneumatic Lithotripsy
      • Open Approaches to Parotid Stones and Lab Preparation Missouri Sialendoscopy Course April 17 2015
      • Salivary Stone Removal with Ductoplasty from Submandibular Gland

Classification of stone location (Goncalves et al 2017)

REFERENCES

Williams, M: Sialolithiasis in  pp 819 - 835 The Otolaryngology Clinics of North America  Salivary Gland Disease ed Rice DH and Eisele D Vol 32  number 5  October 1999

Marchal F, Dulgeuerov P, Becker M, Barki G, Disant F, Lehmann W. Specificity of parotid sialendoscopy. Laryngoscope 2001;111:264-71

Iro H, Waitz G, Nitsche N, Benninger J, Schneider T, Ell C.: Extracorporeal piezoelectric shock-wave lithotripsy of salivary gland stones. Laryngoscope 1992;102:492-4

Luers JC, Beutner D: Letter to the editor 'in reference to Lithotripsy for Refractory Pediatric Sialolithiasis (Laryngoscope 2009;119:298-299)  Laryngoscope 2009 August 17 epub

Su Y, Liao G, Wang L, Liang Y, Chu M, and Zheng G: Sialoliths or Phleboliths? Laryngoscope, 119:1344-7, 2009a

Walvekar RR, Carrau R, and Schaitkin B: Endoscopic sialolith removal: orientationand shape as predictors of success. American Journal of Otolaryngology. vol 30, Issue 3 Pages 153-6 (May 2009)

Su, Zu, Liao, Zheng, Cheng, Han and Shan: Salivary gland functional recovery after sialendoscopy. Laryngoscop 2009b Apr:119(4):646-52

Iro H, Zenk J, Escudier MP, Nahlieli O, Capaccio P, Katz P, Brown J, and McGurk M: Outcome of minimally invasive management of salivary calculi in 4,691 patients. Laryngoscope 2009 Feb;119(2):263-8.

Marchal F: A combined endoscopic and external approach for extraction of large stones with preservation of parotid and submandibular glands. Laryngoscope. 2007 Feb;117(2):373-7

Marchal F, Dulguerov P:Sialolithiasis management: the state of the art. Arch Otolaryngol Head Neck Surg. 2003 Sep;129(9):951-6

Escudier MP and McGurk M. Symptomatic sialoadenitis and sialolithiasis in the English population: an estimate of the cost of hospital treatment. Br. Dent J. 1999;186:463-466

Teymoortash A, Wollstein AC, Lippert BM, Peldszus R, Werner JA. Bacteria and pathogenesis of human salivary calculus. Acta Otolaryngol. 2002:122:210-214

Fritsch MH: Algorithms for Treatment of Salivary Gland obstructions Without access to Extracorporeal Lithotripsy. Otolaryngologic Clinics of North America Volume 42, Issue 6, December 2009, pages 1193-1197 mfritsch@iupui.edu

Buch K, Nadgir RN, Fujita A, Tannenbaum AD, Ozonoff A, Sakai O. Clinical associations of incidentally detected parotid gland calcification on CT. Laryngoscope. 2015;125(6):1360-1365. doi:10.1002/lary.25095

Goncalves M, Schapher M, Iro H, Wuest W, Mantsopoulos K, and Koch M: Sonography in the Diagnosis of Sialolithiasis  J Ultrasound Med 2017; 36:2227-2235

Katz P, Hartl DM, Guerre A. Clinical ultrasound of the salivary glands. Otolaryngol Clin North Am. 2009 Dec;42(6):973-1000, Table of Contents. doi: 10.1016/j.otc.2009.08.009. PMID: 19962004.     (citing French article:  Katz P, Heran F. Pathologies des glandes salivaires [Salivary gland pathologies]. Encyclopedie M edico-chirurgicale (Elsevier, Masson, SAS, Paris), radiodiagnos- tic cœur-poumon 2007;32-800-A-30.)

Kao WK, Chole RA, Ogden MA. Evidence of a microbial etiology for sialoliths. Laryngoscope. 2020 Jan;130(1):69-74. doi: 10.1002/lary.27860. Epub 2019 Mar 12. PMID: 30861582.