Strengthening Bone Density Assessment – Xtreme-CT Scanner & FRAX
When the World Health Organization announced the criteria for diagnosing osteoporosis in 1994, they based their main formula on findings from the bone density scan, which measures bone mineral density. The dual-energy x-ray absorptiometry scan (DEXA) has long been considered the premier way to measure bone mineral density. Today, there is new technology for imaging, known as the Xtreme-CT high resolution scanner. While this Swiss-made technology is currently used in Europe, it has not been FDA approved, and there are only four machines being used clinically in the United States.
The Xtreme-CT produces images that show the architecture of the bone, not just the density. High-resolution x-ray examination along with computer programming provides a three-dimensional look at bone structure. Unlike the DEXA, with the new Xtreme-CT, radiologists are able to look at a cross-section of the outer shell (cortex) of the bone. They can also inspect the spongy network of bone plates that make up the core of the bone.
The Xtreme CT scanner will help to expand research, and has already made discoveries regarding bone health. A study which used a similar machine at the Mayo Clinic revealed that bone loss occurs in both men and women between the ages of 30 and 40. Those results were presented at in 2005, at a meeting of the American Society of Bone and Mineral Research. In the past, it was thought that between the ages of 30 and 40, bone mass was fairly stable because estrogen and testosterone levels had not yet began to decline.
Recently, the National Osteoporosis Foundation released a new algorithm for assessing bone health. Their new Clinician’s Guide to Prevention and Treatment of Osteoporosis is based primarily on a report from World Health Organization, which gives the details of the Fracture Risk Assessment (FRAX). This screening tool looks at more than just the bone mineral density; it also looks at current age, family history, personal history, hip bone density, body mass index, long-term use of glucosteroids, intake of more than two alcoholic beverages daily, smoking, and rheumatoid arthritis. The FRAX algorithm can estimate a person's probability of developing a major bone break.
The FRAX will not replace the traditional bone density scan, but used in conjunction with it could change the recommendations the physician makes about whether a patient should take medication for osteopenia, a condition thought to be a precursor to osteoporosis. The FRAX will give the physician better guidelines about who needs treatment and who doesn’t. The science, research and treatment of aging bones has been progressing the past 20 years, with more changes expected in the future.