Radiology - Other Imaging modalities Flashcards
Where is the parotid duct orifice located?
adjacent to the upper 1st/2nd permanent molar in the buccal mucosa
Where is the submandibular duct orifice located?
Adjacent to the lingual frenum
Where is the sublingual duct orifice located?
Adjacent to the lingual frenum
Why do we image salivary glands? (3)
- Obstruction;
* Mucous plugs
* Stones (sialoliths)
* Neoplastic mass – benign or malignant - Dry mouth
* Sjogrens syndrome associated changes - characteristic US appearance - Swelling
* Neoplastic
* Infection
* Mumps or other viral infection
Where are mucous plug obstructions more commonly found?
parotid gland
Why are ultrasounds used to image salivary glands? (3)
- Superficially positioned in the face (However Struggle to see the deep lobe as it wraps around the medial surface of the ramus)
- it can Assess parenchymal Pattern changes:
- Vascularity
- Ductal dilatation
- Neoplastic masses
- Can use to give a Sialogogue
- Stimulates saliva and improves imaging of dilated ducts (increased dilation)
What does ductal dilatation usually indicate?
obstruction
Briefly describe how ultrasounds work.
Uses high freq soundwaves (short waves) which are transmitted through tissues via a coupling agent (can’t transmit through air – must use gel)
What does hyperechoic mean on an US?
whiter areas
What does hypoechoic mean on an US?
darker areas
What is a bend in the salivary ducts called?
What is the implication of this?
hilum
stones can become obstructed here
What is the first line imaging method for the salivary gland?
why is this first line?
Ultrasound
- no radiation dose to px
(however in practice you may use a mandibular true occlusal for submandibular/sublingual areas as a first line since US may not be readily available)
What are the symptoms of obstructive disease of the salivary glands? (5)
- Mealtime symptoms (Thinking about or eating)
- Pressure
- Prandial Pain over salivary gland
- Prandial swelling
- Rush of saliva into the mouth once swelling gone (salty and thicker)
- Dry mouth
What are the symptoms of obstructive disease of the salivary glands? (5)
- Mealtime symptoms (Thinking about or eating)
- Pressure
- Prandial Pain over salivary gland
- Prandial swelling
- Rush of saliva into the mouth once swelling gone (salty and thicker)
- Dry mouth
What can cause obstructive disease of the salivary glands? (2)
Stones
mucous plugs
Why is the full ductal structure examined if a px is suspected/found to have salivary stones?
if a px has one salivary stone they likely have others elsewhere in the ductal system
What does posterior shadowing of the duct indicate?
There is a calcification present within the duct
What salivary stones can be assessed on an OPT? (2)
anterior parotid stones
submandibular stones
What is Sialography?
Where iodinated radiographic contrast is Injected through the ductal orifice into the salicary duct to look for obstruction
(third line investigation of the salivary glands)
What are the indications for sialography? (3)
- Find out what is causing the symptoms e.g. what is causing obstruction/narrow/stricture
- To assess gland function
- plan for intervention procedures e.g. basket retrieval or balloon dilatation
What radiographic imaging is sialography used alongside? (3)
- Panoramic = static view
- Skull views = static view
- Fluoroscopic approaches = dynamic (live) view
Describe the risks associated with sialography? (4)
- (even although No LA/Scalpel) Can feel discomfort as the contrast is being pushed in against the flow of saliva
Px will feel Pushing and pressure - Swelling
- No risk of infection however if there is infection we can’t complete the procedure it as it pushes bacteria back into the gland
If Pus present = short AB’s and reappoint for 1 weeks time - Risk of allergy to contrast (iodone based) low risk as it’s a small amount of contrast through the duct
What are the alternatives to sialography?
MRI
What are the advantages of sialogrpahy? (2)
No needles/LA
Patient can swallow contrast
