Practice Ultrasound Guided Biopsies
A transparent gelatin mold (ultrasound phantom
) is highly recommended as a training tool while learning how to perform ultrasound guided biopsies
. It helps understand the 3 dimensional ultrasound image and hand-eye coordination needed for this sonography procedure.
How To Make Your Own Ultrasound Guided Biopsy Phantom in 9 Steps
- 1 container (no deeper than 2 inches)*
- 8 packets of Knox gelatin
- 5 olives filled with pimento
- 4 plastic forks
- 2 disposable cups ^
- Hot water
- Plastic wrap
Pour 2 gelatin packets into container;
Spread the content over the bottom.
- Slowly add hot water to gelatin;
Dissolve gelatin while stirring with a fork;
Make sure you form as few bubbles as possible.
- After the gelatin is dissolved fill container halfway;
To speed up the process use cool water;
Add an ice cube or two for even speedier results;
Place in fridge and let solidify.
Place olives in the center of the solidified layer.
Place one packet of Knox gelatin in a clean cup;
Dissolve gelatin with hot water and a fork;
Add some cold water and one ice cube to cool mixture;
Use no more than 8 oz. of fluid;
Make sure there are no bubbles in this layer that will interfere and create artifacts in the Ultrasound image.
- Place semi coagulated mixture (room temperature) directly over olives;
Place in fridge to further harden.
- Make more gelatin following Step Five;
Use 4 packets making one at a time;
The batch needs to be enough to nearly fill the container;
Make sure the liquid will not melt the lower layer.
- Make one more packet of gelatin;
Add while container rests in fridge to prevent overflowing.
- Put a few drops of water on the hardened surface;
Lightly spread water over surface;
Place plastic wrap over mold and smooth out wrinkles;
Plastic protects the surface somewhat from cracking.
*TakeAlong container by Rubbermaid works best for two to three participants
^ Styrofoam coffee cups
How To Use The Ultrasound Guided Biopsy Phantom You Made
Ultrasound probe placement should be in the non-dominant hand.
A light touch is needed during ultrasound guided biopsies – the gelatin mold facilitates this since it will crack if too much pressure is applied.
Move the ultrasound probe/transducer over the phantom and understand the placement of the olives under the probe and on the screen.
Decide where the needle should be placed under the probe. Watch the top of the screen to see where the needle appears in the screen. Note if the needle is traveling towards the “nodule”.
Learn to appreciate the fact that: it is not possible to follow the needle if the transducer is not moved when using the “perpendicular” biopsy approach the needle will appear as a smaller than expected object on the screen very small controlled movements of the probe are best.
Tracks created by the needle placement will remain visible in the gelatin. Move the container around to get another spot to retry a biopsy.