Ultrasound Utilization to Measure Spinal Lengthening with Magnetic Expansion Control (MAGEC System)
Purpose or Case Report: The MAGEC System is a surgical treatment for children with severe spinal deformities. The system utilizes surgically implanted rods, which are periodically extended by an External Remote Control (ERC). The traditional method to measure lengthening progression involved radiation exposure. Ultrasound provides an immediate evaluation with no bio-effects. Additionally, soft tissue changes incurred by rod implantation can be seen, which is difficult to assess with a radiograph. The sonographer acquires both pre- and post-lengthening measurements before and after the ERC is applied to the child’s skin at the level of the rods. The entire process can be completed in minutes within a single outpatient room, for the ease of both patient and parent. Methods & Materials: Children with scoliosis too severe for bracing or casting and too young for spinal fusion, have been traditionally managed with growing rods. This involves repeated surgical elongation, often requiring ten or more surgeries before the child reaches skeletal maturity. MAGEC rods require initial implantation surgery and are expanded with the use of an externally applied ERC. The sonographer scans each rod, measuring the pre-lengthening measurement. The physician utilizes the ERC to externally manipulate the MAGEC rods. The sonographer scans the child again, and can determine if the rods have been sufficiently extended. Additional ERC applications, if necessary, can then be employed. Results: Ultrasound has proven to be a useful tool in the measurement of MAGEC rod extension in patients with severe spinal deformities. It can easily be performed within the examination room in conjunction with the application of the ERC. Conclusions: The use of ultrasound to measure the lengthening of MAGEC rods minimizes radiation exposure, decreases the need for repeated surgeries, and allows for soft tissue evaluation. It streamlines the process of obtaining measurements and can be utilized in one room within an outpatient setting, simplifying the encounter for patient and family.
( Children's Hospital of Philadelphia
, United States