Positioning blocks and sandbags for medical imaging are a crucial component in capturing the correct image, yet often get downplayed as equipment technology improves scanning accuracy. Additionally, the positioning devices you use everyday have probably been in your department longer than you. Because of their long work life, these older accessories may not be in compliance with your organization’s policies.
Increased attention on patient and staff safety, with regards to infection control and inter-department sharing of equipment, has caused many departments to update their policies and/or replace their positioning devices.
Make sure your department is up to speed! Spend a few minutes now to avoid headaches later.
Ideal for patient positioning, support and pressure, sandbags are used and shared among many hospital departments – radiology, ultrasound, physical therapy, etc. While sharing sandbags saves money, problems can occur if the wrong sandbag is brought in to the MRI suite.
Sandbags on the market today may contain ferromagnetic shavings or iron pellets, in addition to sand, to add weight to the bag. Furthermore, grommets can sometimes be made of metal or impure brass (pure brass is non-magnetic). Both of these factors can cause damage to a MRI scanner, or worse, injure the patient or staff.
If you are in the market for new sandbags, the FDA suggests that sites purchase only sandbags that are labeled with the MR Safe or MR Conditional icon. If you don’t know the contents of your current supply of sandbags, assume they are MR Unsafe and label accordingly. Buy new sandbags specifically for MRI, and keep your current set available for other departments’ use.
Foam positioning blocks and extremity immobilizers are the reliable standard to achieve proper patient positioning in the most cost-effective way. Unlike the foam used in the early days, today’s positioners are available in a different foam types and soil-resistant coatings.
Open-Cell Foam: The most economic option for general positioning needs, open-cell foam is lightweight, radiolucent (producing minmal or no shadows or artifacts) and flame resistant. However, its open-cell structure causes it to absorb fluids, and it can’t be cleaned. Because of this, many state health departments and JCAHO are now requiring open-cell foam to be covered or coated with a cleanable surface. Avoid “tricks of the trade” shortcuts! We’ve heard instances where techs wrap open-cell foam blocks in plastic wrap to prevent cross-contamination and fluid absorption. No cases of cross-contamination have been reported by using this technique, but with the increased concern over infection control procedures, it makes sense to purchase new, covered open-foam blocks.
Closed-Cell Foam: Closed-cell foam’s composition makes it highly-resistant to fluid absorption and is a snap to clean. It typically costs more than open-cell foam because it is denser, requiring more material.. Great care must be taken with closed cell foam. Seemingly innocent brushes with fingernails, rings, beltbuckles, etc. will cause small tears. Once tears form, fluid will absorb into the block and can’t be wiped away.
Vinyl Coatings and Covers
Vinyl is a popular choice to cover foam positioning blocks/immobilizers and is available as both a cover and spray-coat.
Vinyl covers are available in different thicknesses and are heat-sealed to prevent fluid absorption, making them easy to clean. A vinyl cover’s seams may show in an image if positioned in the field of view, so this must be considered when positioning. Heavier vinyl covers are not recommended for low KVP techniques.
Sprayed-on vinyl coatings are tough and durable, and can be easily cleaned with aseptic solution or alchohol, or washed with a mild detergent and water. Spray-coat vinyl is not recommended for positioners for thin anatomical areas (like extremities), and its edges may appear as white lines on low dose exposures. Positioners with this covering have a small “blow hole” that releases air when compressed, so it doesn’t damage the seal of the coating. Care should be taken to not get the area around the blow hole wet.
We know there are a lot of options out there when it comes to positioning devices, and we’re here to help. Contact our helpful customer service department at 800-321-6964 with questions or view our full line medical imaging positioning devices. Don't see what you need? Foam positioners in custom shapes and coverings are also available. Get your best image the first time, every time.