EOS 3D Skeletal Imaging

EOS is a specialised X-ray system designed to image the whole skeleton, or large parts of it, in one go. The patient stands inside an open booth rather than lying down, and two X-ray sources move smoothly from head to feet, taking a front and a side image at the same time. This produces full-length pictures of the spine and legs without having to stitch several separate X-rays together. Software then turns these two views into an accurate three-dimensional model, on which the bones and their alignment can be measured precisely.

During the scan the patient simply stands still in a natural position inside the system while the two linked X-ray beams travel down the body. Capturing the front and side views together ensures both images match perfectly, which is what makes the three-dimensional reconstruction so accurate. The whole acquisition takes only about twenty seconds. Because the design is so efficient, the radiation dose is kept very low compared with conventional X-ray, and a special micro-dose mode lowers it even further, which is particularly valuable for children who may need repeated scans as they grow.

EOS is especially useful for the spine and the lower limbs. By imaging the body upright and along its full length, it clearly shows spinal curvatures such as scoliosis and kyphosis and angular deformities of the legs, in the posture in which they actually occur. It is widely used in children and adolescents being monitored for scoliosis, who benefit from its low dose during repeated follow-up, and in adults with spine or limb alignment problems. Because it captures the entire bone length and supports precise measurement, it is also valuable for surgical planning before knee, hip and spine procedures.

The main benefits of EOS are its low radiation dose, its full-length weight-bearing images and the accurate three-dimensional model it produces. Seeing the skeleton as it bears the body's weight gives a truer picture than scans taken lying down, and the low dose makes it well suited to the repeated imaging that conditions like scoliosis require. The scan is quick and painless: the patient stands still inside the open system for about twenty seconds while the images are taken, and there is nothing enclosed about it. There is no recovery time, and a specialist reviews the images and measurements and prepares a report for the treating doctor.