Radiology Associates of Ridgewood NJ offers “Dual Energy CT”, the latest advance in CT scanning technology. By varying the energy level of the x-ray beam in the CT scanner, this technology allows us to optimize certain types of images, as well as identify and quantify certain chemical substances. Although this theoretical concept was first suggested in the 1970s, it took over 3 decades for CT technology to progress to the point that it could be applied clinically to real patients. Some of the exciting new capabilities include:
Characterization of chemical composition of urinary stones – This is of great clinical importance because it influences treatment options. Uric acid stones, which comprise approximately 10% of stones in the United States, can be treated medically (by alkalinizing the urine), whereas calcified stones cannot.
Improved imaging of patients with orthopedic hardware such as joint replacements – Metal hardware can cause severe artifacts on CT scans. Dual Energy CT reduces this artifact both by using a higher energy beam as well as by applying special reconstruction software that minimizes the propagation of the artifact into the adjacent soft tissues.
Diagnosing gout – Gout is a common inflammatory arthritis (in fact, it is the most common inflammatory arthritis in males). It is caused by deposition of uric acid crystal in and around joints. Diagnosis is often challenging, and atypical presentations are frequent. The diagnosis is traditionally made by aspirating the affected joint with a needle. However, these aspirations can be technically challenging and even when performed, are negative in 25% of acute cases. Although high levels of uric acid may be present in the blood, they are not in 42% of acute attacks. Using Dual Energy CT, we assist in making the diagnosis by directly imaging uric acid crystal deposition in and around the joints.
Reducing radiation – CT examinations sometimes require scanning both prior to and after administration of a contrast agent intravenously. For some applications, dual energy CT allows us to scan only after contrast and reconstruct “virtual” non-contrast images without having to scan the patient twice, significantly reducing radiation.
We look forward to future developments on this exciting new technology!