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MAGEC System (magnetically-controlled growing rods) (Nuvasive, Inc.)

The MAGEC System (magnetically-controlled growing rods) (Nuvasive, Inc.) offers a unique treatment for early onset scoliosis (EOS) by providing a noninvasive solution to manage growth and progression of spinal deformity in growing children. The system consists of an adjustable growing rod and an External Remote Controller (ERC) that features innovative magnetic technology allowing for noninvasive control of the implanted device. Other distraction-based treatments for EOS require on-going distraction surgeries throughout treatment. After an initial procedure to implant the MAGEC Rod, the device can be distracted or retracted during routine outpatient visits. The MAGEC System is designed to reduce the impact of EOS on the lives of patients and families by eliminating planned distraction surgeries and the risks associated with them while providing optimal clinical outcomes.

MRI Safety Information
Non-clinical testing demonstrated that the MAGEC System is MR Conditional. The following conditions must be followed:
A patient with this device can be scanned in an MR system meeting the following conditions:

- Static magnetic field of 1.5 Tesla (1.5 T)
- Maximum spatial field gradient of 3000 gauss/cm (30 T/m)

-Maximum MR system reported, whole body averaged specific absorption rate (SAR) of 0.5 W/kg at 1.5 T

Under the scan conditions defined above, the MAGEC system is expected to produce a maximum temperature rise of no greater than 3.7° C after 15 minutes of continuous scanning.

Caution: The RF heating behavior does not scale with static field strength. Devices that do not exhibit detectable heating at one field strength may exhibit high values of localized heating at another field strength.
- The patient should not be permitted to roll on the table, as this motion may cause unintended lengthening/shortening of the implant.
- The External Remote Controller, Manual Distractor, and Wand Magnet Locator are MR Unsafe. Do not bring them into the MRI scan room.
-In non-clinical testing, the image artifact caused by the MAGEC® system extends beyond the imaging field of view when imaged with a gradient-echo pulse sequence in a 1.5 T MRI system. However, imaging in locations approximately 20 cm away from the actuator of the MAGEC System may produce images in which anatomical features may be discerned.


  Shellock R & D Services, Inc. email: Frank.ShellockREMOVE@MRIsafety.com.
  © 2004- by Shellock R & D Services, Inc. and Frank G. Shellock, Ph.D. All rights reserved. (v3.1.109)