Mouldroom Flashcards
What areas are important when fitting and moulding a thermoplastic mask for whole brain irradiation
ITN, SOM, nose bridge
What treatments are shells used for
Head and neck, chest, breast, limbs and brain
When is vas gauze more preferable to jelly bolus
avoiding air gaps in ears and nose to avoid scatter and ensure beam dosimetry
When is jelly bolus more preferable to vas gauze
to mock skin surface
What are the characteristics of the ideal bolus material
No bubbles
Uniform thickness and consistency
Durable, non-toxic, inexpensive, easily disposable
Contrast the use of alginate over regular plaster bandage
alginate is finer than plaster porous and allows better detail and definition
What precautions should be taken for alginate and plaster bandage application and usage
Check allergies in latex
Can harden in 45 seconds
Stir fast to remove air, clumps before colour changes
Can harden on lip or in airways if ingested or breathed in
Suitable site for wax use and features of wax
Facial structures
Heat needed for use, less detailed, dries quicker
Suitable site for plaster use and features
Whole face, not as detailed, dries slowly and uncomfortable
Alginate use
Fingers
What considerations are required in constructing a mouthpiece
Sup-inf or L/R orientation
Tongue positioning
Lip protection (include or exclude)
Separation
Why are mouthpieces used
For keeping jaw position stable
What potential difficulties could occur when making a mouthpiece
- patients biting on it too hard
- sup/in or L/R orientation wrong
- wax not halfway above syringe
- bitemark not on syringe
Why is wax used to cover all internal shields
To reduce scatter of secondary electrons
What is the purpose of the serration on the shields
Helpful for cosmetic purposes. Helpful for smoother edges as dosage is given. May not be beneficial in fractionated dose.
