15 Sep Detecting Coronary Calcifications – How Reveal™ 35C Can Help
One emerging application for dual-energy X-ray subtraction is the opportunistic detection of coronary calcifications. Coronary artery calcifications (CAC), or the presence of calcium buildups in arteries that supply blood to the heart, is common in patients with coronary heart disease (CHD)3.
A 2021 update by the American Heart Association maintains that CHD is the leading cause of death attributable to cardiovascular disease (CVD) in the US. CVD accounted for approximately 18.6 million deaths in 2019 and is therefore the leading cause of death worldwide1.
An early diagnosis of CAC can help determine a patient’s risk of CHD or serious cardiac events, and although more understanding may still be needed, diagnosis and treatments can benefit patients’ health and improve their overall care.
A recent study, published in 2020, assessed the ability of physicians to detect coronary calcifications using standard X-ray supplemented with dual energy X-ray images for three key reasons: the accessibility, accuracy, and cost4. Their findings show that dual-energy X-ray supplemental images can help detect coronary calcifications and, in many cases, that CAC were made more visible when compared to other processing and screening methods. Diagnosis was confirmed with computed tomography (CT) images.
Two historical reasons why dual energy subtraction X-ray techniques were not adopted for mainstream diagnostics are motion artifacts that cause blurred images, and the higher radiation dose to the patient due to two exposures which is especially problematic when lateral X-ray views to visualize the retrocardiac space are desired. KA Imaging’s solution to these problems is Reveal™ 35C – a single exposure, dual-energy X-ray detector that provides three images, a standard X-ray supplemented with bone and soft tissue dual energy X-ray images, all acquired simultaneously with zero motion artifacts. Reveal 35C also uses the same X-ray technique, same dose and the same X-ray source as a standard chest X-ray, which alleviates concerns about excess radiation.
Here’s how KA Imaging’s Reveal 35C can help detect coronary calcifications:
As described in the 2020 study, X-ray is already an ordered procedure when trying to detect coronary calcifications and is accessible to many people in different care settings, so it would be beneficial to continue this diagnostic practice4. Using high quality dual-energy X-ray would help a much larger group of people gain the benefits of early detection of CHD, so they could receive prompt treatment.
Reveal 35C can be used anywhere a standard X-ray is used because it provides a standard X-ray and two supplemental dual energy X-ray images using a single exposure. It is portable, retrofittable and can add true dual energy capability to any X-ray system, as it is fully compatible with existing fixed, mobile and portable X-ray systems.
The fact that coronary calcifications could be detected in dual-energy chest X-rays was shown in this 2020 study, and the ability to detect a large number of patients with CAD accurately compared very favourably to other screening methods4. Although CT scans were used to verify the visualization of coronary calcifications, X-ray uses far less radiation, and as mentioned previously, is much more accessible.
Moreover, lateral X-ray views were recently reported at the RSNA 2020 symposium to help the visualization of CAD because of better visualization of the retrocardiac area2. However, motion artifact and higher radiation dose of older generation dual energy subtraction systems remains an impediment to adoption. In contrast, Reveal 35C enables lateral views with zero motion artifact using the same technique, dose and X-ray source as a standard chest X-ray.
As previously mentioned, X-ray is already an ordered exam for many patients, so any additional cost to the health care system would be minimal when using X-ray imaging to detect coronary calcifications. The 2020 study calls this significant, because recent reports show increases in cardiovascular disease, potentially due to obesity and diabetes being on the rise in America. It is, in fact, dubbed “America’s costliest disease” and costs are predicted to double to $1.1 T by 20234.
Reveal 35C is available at a fraction of the cost of other DES systems, and can be retrofitted to existing digital and analog, fixed and mobile X-ray equipment. The most significant savings would be the ten times lower purchasing and operating costs compared to computed tomography systems (CT), which are typically used for diagnostic purposes, as well as the economic benefits of early CHD detection.
1. American Heart Association. (2021). 2021 Heart Disease and Stroke Statistics Update Fact Sheet at-a-Glance. https://www.heart.org/-/media/phd-files-2/science-news/2/2021-heart-and-stroke-stat-update/2021_heart_disease_and_stroke_statistics_update_fact_sheet_at_a_glance.pdf
2. Boswell, G., et al. (2020) Dual Energy Lateral CXR: Opportunistic Detection of Coronary Calcium. RSNA.
3. Liu, W., Zhang, Y., et al. (2015). Current Understanding of Coronary Artery Calcifications Journal of Geriatric Cardiology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712374/
4. Song, Y., Wu, H. et al. (2020.) Detection of Coronary Calcifications with Dual Energy Chest X-rays: Clinical Evaluation. The international Journal of Cardiovascular Imaging.