"X"ing out X-rays: New way to look inside the body

Published On: Nov 05 2012 11:31:49 AM CST

BACKGROUND:  Scoliosis is a sideways curvature of the spine that occurs most often during the growth spurt just before puberty. While scoliosis can be caused by conditions such as cerebral palsy and muscular dystrophy, the cause of most scoliosis is unknown. Most cases of scoliosis are mild, but some children develop spine deformities that continue to get more severe as they grow. Severe scoliosis can be disabling. An especially severe spinal curve can reduce the amount of space within the chest, making it difficult for the lungs to function properly. Children who have mild scoliosis are monitored closely, usually with X-rays, to see if the curve is getting worse. In many cases, no treatment is necessary. Some children will need to wear a brace to stop the curve from worsening. Others may need surgery to keep the scoliosis from worsening and to straighten severe cases of scoliosis. (Source: MayoClinic)


TYPES/SIGNS:  Signs and symptoms of scoliosis may include: Uneven shoulders, one shoulder blade that appears more prominent than the other, uneven waist, or one hip higher than the other. If a scoliosis curve gets worse, the spine will also rotate or twist, in addition to curving side to side. This causes the ribs on one side of the body to stick out farther than on the other side. Severe scoliosis can cause back pain and difficulty breathing. (Source: MayoClinic)


IMAGING TESTS: Plain X-rays can confirm the diagnosis of scoliosis and reveal the severity of the spinal curvature. If a doctor suspects that an underlying condition — such as a tumor — is causing the scoliosis, he or she may recommend additional imaging tests, including: Magnetic resonance imaging (MRI). MRI uses radio waves and a strong magnetic field to produce very detailed images of bones and soft tissues. Computerized tomography (CT). CT scans combine X-rays taken from many different directions to produce more-detailed images than do plain X-rays. Bone scans involve the injection of a radioactive material, which travels to the parts of your bones that are injured or healing. (Source: MayoClinic)


NEW TECHNOLOGY:  The EOS is able to obtain a standard PA and lateral scoliosis film with 1/10 the amount of radiographic exposure of standard low-dose films. The EOS is able to obtain 3-D visualization of the spine with 1/1,000 the dose of a CT scanner. In addition to providing a standard 2-D film, EOS also allows for 3-D reconstruction of individual bone position, rotation and orientation. Not only does the EOS capture a simultaneous PA and lateral radiograph of the spine, it also has the capability of whole body radiographs in the standing position. This comprehensive view of spine and joint alignment allows for a more accurate assessment of deformities. (Source: Children’s Hospital of Wisconsin)

 

Dr. Suken A. Shah, Division Chief of the Spine and Scoliosis Center at the Nemours/Alfred I. DuPont Hospital for Children at Wilmington, Delaware, talks about a the new EOS scanner and how it could benefit patients with scoliosis.

So we were talking about some pretty exciting news in scoliosis and the first thing I would like to go over with you is the new EOS scanner?

Dr. Shah: We’re really excited about this scanner.  The hospital purchased the technology this past spring, and we’ve really been able to offer it to any number of patients that need x-rays; anyone with a full spinal x-ray or lower extremity x-rays is eligible to have their x-rays done here. The two big advantages are that it’s ultra-low-dose radiation, so this is a compelling reason to have x-rays. Kids that are having multiple x-rays over their lifetime as part of their growing skeleton can be exposed to a tremendous amount of radiation for medical purposes.  This really keeps that to a minimum amount over the course of their lifetime, and might prevent their chances of having a malignancy as an adult.  More so, the images are really outstanding.  We are able to see clarity, contrast, and detail that we weren’t able to see prior to this technology being available to us. The really exciting thing for some of the severe curves we treat with surgery is that we can evaluate our outcomes in three dimensions because this technology combined with computer software can take two-dimensional images and stitch them together and make a three-dimensional model of the spine that we can rotate and look at and appreciate finer detail that we weren’t able to see before.  So it really allows us to see things that weren’t obvious to us before.

It’s not your typical x-ray machine?

Dr. Shah: No, not at all.  In fact, the developers of this technology won a Nobel Prize for this technology, and it’s really important to give this to the community.

How big of a breakthrough would you say this is in x-ray technology?

Dr. Shah: MRI’s a great breakthrough because it allows you see other than the bone, the soft tissues, ligaments, and spinal cord.  I would put this very close to that in terms of the three-dimensional capability, but the benefit to the patient is huge because ultra is much less radiation than there was in the past.

It’s probably one of the biggest developments that happened in more than 100 years?

Dr. Shah: It’s the biggest development in x-rays since the invention of x-rays, but in terms of imaging it’s definitely up there with some three dimensional scans, and MRIs, yes.

How many x-rays would they have to get versus now?  Would it always be a typical number that they would have to get over the course of their lifetime versus this?

Dr. Shah: Well, it’s really individualized based on what kind of curve the patient has and how young they are.  The problem is when you’re growing the curve can increase and we need some way to monitor that, x-ray is really the best way to see that. If the patient is eight years old when they’re diagnosed with scoliosis and their x-rayed twice a year, every year until they’re done growing, I mean, that’s 20 x-rays.  If they’re getting treated at the same time with a brace, if they’ve  had surgery, each of those subsequent x-rays and follow-up visits and so forth is additive. So, the radiation dose is cumulative, we want to keep that to a minimum and with this we’re able to do that.

When you do this then, how often are they exposed to radiation?

Dr. Shah: They’re exposed anytime they get into the machine. It’s not necessarily a frequency change, but each x-ray is a 10th or a quarter of the radiation they were getting.  So feasibly they could get 10 x-rays in EOS and it only adds up to one conventional x-ray.

Can you talk a little bit of the story behind this mother and daughter?

Dr. Shah: So Mrs. Smith, Alyssa’s mother, had surgery here in 1985. She was diagnosed as a young child and she was followed here, just like we just talked about, twice a year with x-rays subsequently leading up to the fact that during her growth spurt the curve became much more severe and she needed surgery to alleviate some of the problems that we see with severe scoliosis. Problems like decreased pulmonary function, a change in body position, and we want to prevent the consequences of scoliosis during aging, such as pain and disability.  She had the surgery done 20 years ago and she’s doing extremely well now as a mother of three and is quite active and healthy, but now she’s seeing the same thing with her daughter. Her daughter has a mild to moderate curve and what is her progression potential is what we really want to know.  Right now the curve is small, but you can see the difference in their size.  Alyssa’s got five more years to grow and that curve could potentially become just as severe as her mother’s.  So we’re using this new technology and this new knowledge about growth of the spine, about progression potential for scoliosis, and a less dangerous way to monitor scoliosis with low-dose radiation x-rays.  We administered a genetic test to her today that will determine her risk of progression to a severe curve, and if that risk is very high like it was in her mother’s, we may be able to use novel treatments or start earlier bracing to prevent her preparation to need surgery.  We didn’t have any information before, we would treat everybody based on the algorithms in our text book and in our medical journals; if your curve is at 25 to 40° you’ll get a brace and we’ll see if that works.  Well with her genetic testing we’re going to be able to customize treatment and choose the best few options for her, rather than the population as a whole.

How severe was her mother’s curve, then?

Dr. Shah: She doesn’t recall her exact x-rays, we’re going to pull her records but back then in the 80s surgery wasn’t done for curves less than 50 or 60°. So it was probably pretty severe.

Can you talk about the EOS machine?

Dr. Shah: We didn’t model this patient, but if we did you could see the three-dimensional deformity where there’s a rib hump on this side and there’s quite a twist into the spine. We’ve been able to eliminate a lot of that rotation with this new generation instrumentation and you can see the ribs are much more even now.  So this patient who had a previous high rib hump is now quite flat and looking at him you wouldn’t even know he had scoliosis anymore.  We’re able to achieve a three-dimensional correction to scoliosis now that we can actually see the spine in 3-D.

 

FOR MORE INFORMATION, PLEASE CONTACT:

 

Steve Maurer

Spine and Scoliosis Center

(302) 651-5012
smaurer@nemours.org