SIALOGRAPHY.pptx

SIALOGRAPHY

1. SIALOGRAPHY DR.AMBIKA.PATIL

2. SIALOGRAPHY Sialography can be defined as the radiographic demonstration of the major salivary glands by introducing a radiopaque contrast medium into their ductal system Very effective for the diagnosis of obstruction whether caused by stones or strictures.

3. indications To determine the presence and/or position of calculi or other blockages. To assess the extent of ductal and glandular destruction secondary to an obstruction To determine the extent of glandular breakdown and as a crude assessment of function in cases of dry mouth

4. Contraindications Allergy to compounds containing iodine Periods of acute infection/inflammation, when there is discharge of pus from the duct opening When clinical examination or routine radiographs have shown a calculus close to the duct opening, as injection of the contrast medium may push the calculus back down the main duct where it may be inaccessible

5. The procedure is divided into three phases. The preoperative phase The filling phase The emptying phase

6. Preoperative Phase This involves taking preoperative (scout) radiographs before the introduction of the contrast medium, for the following reasons: To note the position and/or presence of any radiopaque obstruction To assess the position of shadows cast by normal anatomical structures that may overlie the gland, such as the hyoid bone To assess the exposure factors.

7. Filling phase Duct orifice needs to be found clinically, probed and dilated, and then cannulated

8. The contrast medium can then be introduced. Three main techniques are available for introducing the contrast medium

9. Emptying phase The cannula is removed and the patient allowed to rinse out. The use of lemon juice at this stage to aid excretion of the contrast medium After one and five minutes, the emptying phase radiographs are taken, usually oblique laterals. These films can be used as a crude assessment of function. If any ammount of contrast medium is remaining then sialogogues are given.

10. The three main techniques available for introducing the contrast medium into the ductal system, having cannulated the relevant duct orifice, include: Simple injection Hydrostatic Continuous infusion pressure-monitored

11. Simple injection technique Oil-based or aqueous contrast medium is introduced using gentle hand pressure until the patient experiences tightness or discomfort in the gland, (about 1.0 ml for the parotid gland, 0.8 ml for the submandibular gland)

12. Hydrostatic technique Aqueous contrast media is allowed to flow freely from an overhead reservior into the gland under the force of gravity until the patient experiences discomfort

13. Continuous infusion pressure-monitored technique Using aqueous contrast medium, a constant flow rate is adopted and the ductal pressure monitored throughout the procedure.

14. Contrast media used The types of contrast media suitable for sialography are all iodine-based, and include: Ionic aqueous solutions, including: Diatrizoate (Urografin) Metrizoate (Triosil) Non-ionic aqueous solutions , including: Iohexol (Omnipaque) Oil-based solutions , including: Iodized oil, e.g. Lipiodol (iodized poppy seed oil) Water-insoluble organic iodine compounds, e.g. Pantopaque. Most radiology departments use aqueous solutions

15. Sialographic interpretation Normal sialographic appearances of the parotid gland TREE IN WIN TER APPEARANCE

16. Normal sialographic appearances of the submandibular gland BUSH IN WINTER APPEARANCE

17. Pathological appearances Sialographic appearances of calculi include : Filling defect(s) in the main duct Ductal dilatation proximal to the calculus The emptying film usually shows contrast medium retained behind the stone

18. Sialographic appearances in Sjögren’s syndrome Sialographic appearances in Sjögren’s syndrome include SNOWSTORM

19. Sialographic appearances of intrinsic tumours Sialograph of a right parotid showing a large area of underfilling in the lower lobe (arrowed) caused by an intrinsic tumour