Immobilization of the Cranial Spinal Axis with Alpha Cradle Device

Jane V. Berby, RTRT
J. David Todd, RTRT
Indiana University Hospitals
Indianapolis, Indiana

Treatment of the cranial spinal axis can create difficulties with the reliability and reproducibility of the treatment portals. Most patients are uncomfortable lying prone, which creates positioning problems. Many institutions utilize the prone pillow when patients are to be treated in the prone position. While the prone pillow has improved patient comfort, it has not been able to assure the therapist that the patient is in the exact treatment position. Because of this variable the Department of Radiation Oncology at Indiana University Medical Center has developed a customized immobilization device for the treatment of cranial spinal ports. We have found that immobilization of the cranial spinal axis with the Alpha Cradle device increases the reproducibility of this treatment set up.
Our customized prone immobilization device utilizes Smithers Medical Products, Inc. ALPHA CRADLE® brand devices, aquaplast and Styrofoam®. Once the required products have been acquired a therapist can make this immobilization device in ten simple steps.

1) Prepare the ALPHA CRADLE® foaming agents as directed by the manufacturer. Once mixed pour the foam into the provided bag (Fig. 1).

2) Next, spread the foaming agents evenly inside the bag. The foaming agents should be spread over an area large enough so that the ALPHA CRADLE® device will extend from the patient’s shoulders to their hips. After the foaming agents are spread out fold the bag to the opened end so that the foaming agents are contained (Fig. 2).

3) At this point the patient is instructed to lie on the polyform bag in the prone position. Utilizing the slatted board and wood inserts the bag is formed around the patient. Special attention must be paid to mold the ALPHA CRADLE® device around the patients shoulders and arms (Fig. 3).

Fig. 1 Carefully pour foam deep into bag.

Fig 2. End of bag is carefully folded.

Fig. 3 Keep the rising bag of foam tightly against the patient using the dividers.

4) After the ALPHA CRADLE® form has hardened the patient is helped to a sitting position. The mold is then flipped upside down and double sided foam tape is placed on the ALPHA CRADLE® form. The protective paper is then removed and the mold is turned back over and squarely placed on a large sheet of Styrofoam® (3’ x 4’ x .5”) which serves as the base (Fig. 4).

5) The patient is then asked to lie back down in the mold and a piece of Styrofoam® that is approximately 2”-3” high is positioned under the forehead for support. It is very important that the head be positioned in a neutral position with the face straight down. The position of the support piece is marked and it is then secured with double sided foam tape (Fig. 5)

6) Once the ALPHA CRADLE® form and forehead support have been secured a final piece of Styrofoam® is secured to the top of the main Styrofoam® base. A warmed piece of Aquaplast® is then placed on the edge of the ALPHA CRADLE® form where the patient’s chest would be. The Aquaplast® is then stretched across the forehead support and molded around the top piece of Styrofoam® (Fig. 6).

7) The patient is then instructed to lie down; the head is positioned and the aquaplast is molded to the patient’s face. Once the aquaplast has hardened the patient can get up (Fig. 7).

To provide the immobilization device with greater stability, 2”-3” nails are pushed through the ALPHA CRADLE® form and Styrofoam® base. It is very important that the nails be of correct length so that the protruding points will not injure anyone (Fig. 8).

9) The last step we take in this process is to create greater patient comfort. To do this we place moleskin over the aquaplast where it meets the ALPHA CRADLE® form, Additionally, we cut pieces of moleskin to place on pressure points in the mask. Most often the moleskin is put in the chin and forehead areas (Fig. 9).

10) The final product, a customized cranial spinal immobilization mold (Fig. 10).

Fig. 4 Double-sticky tape is placed on the back of the form.

Fig. 5 The form is mounted on a support piece.

Fig. 6 Aquaplast® is molded around the patient’s face by placing it on the Styrofoam® support pieces.

Fig. 7 Aquaplast® has been molded to patient’s face.

Fig. 8 Nails must be placed carefully.

Fig. 9 Moleskin is placed on chin and forehead areas.

Fig. 10 Completed form.

Increased immobilization is the main advantage of this ALPHA CRADLE® device. Additionally, we have found three other advantages of this customized mold. First, it provides the patient with greater comfort while lying in the prone position. Secondly, we have found that the therapists are less apprehensive when positioning and treating patients with cranial spinal portals. Thirdly, many of the positioning marks can be placed on the mask and not the patient’s face.