concise knowhow on pathogenesis, clinical presentation, diagnostic modalities and treatment of sialolithiasis

1. SIALOLITHIASIS :

2. INTRODUCTION :
• Is a pathological condition, characterized by the presence of one/more
calcified structures within the salivary gland itself or within its duct
• In general, sialoliths present one core partially or highly mineralized
structure surrounded by concentric layers of organic and mineralized
matter that alternate in succession following a chronologic sequence
• Obstructive sialadenitis (from stones or strictures) accounts for
approximately one-half of benign salivary gland disorders1
• The submandibular gland is most often affected (80% to 90% of cases),
and nearly all other cases involve the parotid duct2,3
• Most cases of submandibular sialoliths are larger & lodged intraductally,
while parotid sialoliths are smaller in size and lodged within the gland
1. Epker BN. Obstructive and inflammatory diseases of the major salivary glands. Oral Surg Oral Med Oral Pathol.1972;33(1):2-27
2. Levy DM, Remine WH, Devine KD. Salivary gland calculi. Pain, swelling associated with eating. JAMA. 1962; 181:1115-1119
3. Bodner L. Salivary gland calculi: diagnostic imaging and surgical management. Compendium. 1993;14(5):572, 574-576, 578

3. PATHOGENESIS :
• Multifactorial event
Formation of a small nidus
within glands or ducts
Overtime, concentric lamellar
crystallizations occur due to
precipitation of Ca salts
Size increase as layer after
layers of salt gets deposited,
just like growth rings in a
tree
Microliths can be expelled in
the mouth alongwith salivary
secretions, but those which
cannot be expelled continue
to enlarge until a duct or its
branch is completely
occluded

4. CLINICAL PRESENTATION :
• In many cases, sialoliths remain symptomless, and can only be detected on
routine radiographic examination
• Patients with sialolithiasis typically present with postprandial salivary pain and
swelling. They may have a history of recurrent acute suppurative sialadenitis4
• The chief complaints are intermittent pain, discomfort and recurrent mandibular
swellings especially during meals
• The pain can be felt like a pulling, drawing or a stinging sensation in mild cases
due to partial obstruction of the duct due to sialolith
• Severe and stabbing type alongwith appreciable swelling incase of complete
occlusion
• The affected glands become enlarged and firm but still movable
• Sialoliths at submandibular salivary glands can be palpated by bimanual
palpation with fingers of both hands
4. Kevin f. Wilson,; Jeremy d. Meier, and P. Daniel Ward; salivary gland disorders ; Am fam physician. 2014;89(11):882-
888

5. CLINICAL PRESENTATION :
• Sialoliths usually form unilaterally, however bilateral sialoliths have also
been reported
• Secondary infection causes pain, swelling and formation of sinus tracts or
fistulas. Chronicity may also lead to development of an ulcer
• In chronically obstructed glands, necrosis of the gland acini and lobular
fibrosis may occur, which results in complete loss of secretion from the
gland
• Sialoliths do not cause xerostomia, since they involve only one or two
glands and/or associated structures

6. DIAGNOSTIC FINDINGS :

7. IMAGING MODALITIES :
Sialoendoscopy
MRI
CT scan
USG
Sialography
Conventional Radiography

8. CONVENTIONAL RADIOGRAPHY :
• Plain film radiography is typically the
appropriate starting point for
imaging the major salivary glands
from a cost-benefit point of view
• Not all stones are radiopaque. Hence,
it is expedient to use about half or
less of the usual exposure for better
identification
• Plain radiography is able to visualise
only 80-90% of submandibular stones
and around 60% of parotid duct
stones presumably due to differences
in the composition of the secretion of
the parent glands

9. CONVENTIONAL RADIOGRAPHY :
• As a rule, only siaoliths in the anterior part of the duct, anterior to the
masseter muscle, can be imaged on an intra oral film
• Sialoliths in the distal portion of stenson’s duct or in the parotid gland are
difficult to demonstrate by intraoral or extraoral views
• However, a PA skull projection with the cheeks puffed out may move the
image of the sialolith free of the bone, rendering it visible on the projected
image
• Oblique views are usually preferred over panoramic views as they are able
to project the stones away from the adjacent bone and teeth

10. SIALOGRAPHY :
• Gold standard for diagnosis of salivary gland
pathology
• Sialography or radiosialography is the radiographic
visualization of the salivary gland following
retrograde instillation of contrast material into the
ducts
• It excels at delineating the exact size and location
of stones with in salivary gland ducts. The stone
will be visualised as a filling defect within the duct.
In some cases contrast will not be able to pass
beyond the stone

11. SIALOGRAPHY :
Indications
• Evaluation of functional integrity of
salivary glands
• Incase of obstructions
• Evaluate ductal anatomy
• Rule out salivary gland pathology
incase of facial swellings
• Incase of intra-glandular neoplasms
Contraindications
• Persons allergic to iodine and/or
contrast medium
• Acute infection
• Calculi located in anterior part of the
salivary duct
Adverse reactions
• Pain on injection
• Post procedural infection
• Ductal rupture
• Extravasation of contrast media
• Allergic reaction to iodine

12. ULTRASONOGRAPHY :
• Non invasive, alternate method
• A typical USG image of a stone involves: an echogenic, round or oval
structure, producing an acoustic shadow
• Stones in salivary ducts may lead to the distension of the duct above the
obstacle, which may be shown on USG
• Despite many advantages of this method, USG turns out to be less precise
in differentiating a cluster of stones from a single, large stone

13. COMPUTED TOMOGRAPHY :
• Unenhanced CT is the superior method in sialolithiasis detection ,
especially in case of painful salivary glands and suspicion of a few, very tiny
calculi
• CT detects calcifications with high sensitivity, but its disadvantage is a
poor visualisation of salivary ducts and lesions within them, as well as
patient’s exposition to ionising radiation and a relatively high cost of the
examination
• Recent alterations have proposed the use of CBCT in sialolithiasis
diagnosis. This method produces high-resolution, 3D images of bony
structures of the head and neck, with the use of up to 15 times lower
ionising radiation dose, and being much cheaper

14. COMPUTED TOMOGRAPHY :

15. SIALO-MRI :
• Sialo- MRI is a diagnostic, non-invasive, method recently introduced, with
promising results, in the evaluation of salivary gland disease
• It is performed using a heavily T2-weighted sequence that allows the
imaging of the salivary ducts because the containing saliva appears
hyperintense and the surrounding tissue appears hypointense
• This technique produces sialographic images but without contrast medium
injection and without the disadvantage of ionizing radiation (CT and
contrast sialography).
• An important advantage of sialo-MRI is the fact that the structural
anatomy of the salivary glands remains unchanged with this technique,
which allows an exact delimitation of the glandular acini and duct

16. SIALO-MRI :
2 parts
Anatomical – which also
contributes to determine the
relationship with adjacent
structures thanks to its
dimensional, morphological and
structural examination of the
parotid and submandibular
Sialographic – which shows
only the ductal components
and possible liquid areas
taken by the slices, which
improves after stimulation
using citric acid

17. SIALO-MRI :
• Sialo-MRI offers a simultaneous evaluation both of the parotid and
submandibular glands
• Allows acute to be differentiated from chronic inflammation, on the basis
of the signal intensities, T2 weight in particular, since it is possible to
perform this method even during acute inflammation
Crucial to be used in conjunction with conventional radiography and USG since it is
impossible to visualize the stones directly by sialo-MRI, these being hypointense both
in T1 and T2 weights and, in particular, in the presence of small calculi

18. SIALOENDOSCOPY :
• The causes of salivary duct stenosis remain unknown in 5–10% of cases
• The diagnostic gap is filled by sialoendoscopy that allows for a direct
visualisation of the salivary duct lumen, i.e. visualisation of calculi, mucosal
plugs, foreign bodies and polyps.
• Introduced for the first time in the early 1990s by Katz, sialendoscopy uses
semi-rigid or rigid miniaturized endoscopes with optical fibers providing
high-quality images to explore the parotid and submaxillary salivary ducts
• For diagnostic purposes, sialendoscopy is superior to imaging for
obstructive pathologies. The radiolucent stones, stenosis, polyps, mucosal
plugs and foreign bodies often missed by imaging methods, can be
visualized by this technique
• When used for therapeutic purposes, sialendoscopy is a minimally invasive
and non-traumatic surgical technique enabling endoscopic stone removal,
stricture dilatation and salivary gland lavage

19. SIALOENDOSCOPY :
• When used for therapeutic purposes, sialendoscopy is a minimally invasive
and non-traumatic surgical technique enabling endoscopic stone removal,
stricture dilatation and salivary gland lavage

20. SIALOENDOSCOPY :
The only contraindication reported in the literature
is acute salivary gland infection due to the
increased risk of perforation of inflammatory ducts
Some authors recommend dilatation of the ductal
openings before performing sialoendoscopy.
Others recommend papillotomy

21. TREATMENT :
Symptomatic
• Antibiotics
• Anti inflammatory agents
• Sialogogues
• Glandular Massage
Surgical
• Sialoendoscopy
• Sialodochotomies with papillotomies
• Sialoadenectomy
Non surgical
• Lithotripsy
• Radiofrequency devices (Surgitron RF
device)

22. LITHOTRIPSY :
• Extra corporeal Shock wave lithotripsy is proposed as a non- invasive
procedure incorporating ultrasound shockwaves applied from a transducer
outside the body to crush or pulverize the sialolith inside the tissue
• The purpose of this treatment is to disintegrate the salivary stone into
concentrations smaller than 2 mm to permit spontaneous or induced
salivation to flush out the sandy material

23. LITHOTRIPSY :
• Continuous ultrasound recordings through an inline transducer positioned
along the longitudinal axis of the reflector allow waves to be precisely
directed at stone and monitor its disintegration
• Immediate side effects may include mild pain, gland swelling, self-limiting
duct bleeding and cutaneous petechiae

24. DECISION TREE FOR DIAGNOSIS & MANAGEMENT OF
SIALOLITH:

25. CONSOLIDATED DECISION TREE FOR DIAGNOSIS &
MANAGEMENT :

26. REFERENCES :
• Oral and Maxillofacial Pathology; 3rd edition; Neville; page 459 -462
• Burket’s Oral Medicine; Greenberg, Glick, Ship; 11th edition ; page 193-200
• Essentials of Oral Pathology; 3rd edition ; Swapan Purkait; page 201 – 04
• Iwona-Rzymska Grala et al; Salivary gland calculi – contemporary methods
of imaging; Pol J Radiol. 2010 Jul-Sep; 75(3): 25–37.
• T Sridhar, N. Gnanasundaram ; Ultrasonographic Evaluation of Salivary
Gland Enlargements: A Pilot Study. International Journal of Dental Sciences
and Research, 1(2), 28-35
• K Yonetsu et al; Sonography as a replacement for sialography for the
diagnosis of salivary glands affected by Sjögren's syndrome; Ann Rheum
Dis 2002;61:276-277

27. REFERENCES :
• Kevin f. WILSON et al; Salivary Gland Disorders; Am Fam Physician.
2014;89(11):882-888
• A. Meyer et al; Sialendoscopy: A new diagnostic and therapeutic tool;
European Annals of Otorhinolaryngology, Head and Neck diseases (2013)
130, 61—65
• G Revadi et al; Submandibular Intraductal Calculi Removal as an Office
Procedure With Radiofrequency Device; Med J Malaysia Vol 65 No 1 March
2010
• www.google.com/images

28. THANK YOU & GOOD DAY ..