Expressing their reasoning in a Citizen Petition filed by the International Contrast Ultrasound Society (ICUS), the groups argue that scientific research and studies support UCAs as safe diagnostic imaging products and that the black box misrepresents risks, leading providers to refrain from using the agents in situations where they are medically necessary and making patients apprehensive about using them.
“When the black box was put on the ultrasound contrast agent, there wasn’t enough data to understand their safety,” a spokesperson for ICUS told HCB News. “Since that time, there has been a considerable amount of data that’s been produced worldwide, and a significant amount of clinical experience and growth in the field. It all points to a very strong safety profile for ultrasound contrast agents. As a result of that, the black box misrepresents the level of risk and deters use of agents by some physicians.”
An indicator of the highest level of risk associated with products approved by it, the FDA introduced the "black box" for UCAs in 2007. It has since downgraded packaged insert contraindications three times, as well as removed a 30-minute monitoring requirement for patients with pulmonary hypertension or unstable cardiac cardiopulmonary conditions, and approved new indications for use in adults and children, according to the petition.
The societies claim that UCAs reduce the need for unnecessary downstream tests and related costs by improving the reliability of real-time ultrasound scans, as well as speed up diagnosis and access to appropriate therapy, reduce lengths of stay in the hospital and improve patient care, outcomes and experiences.
They also say that safety studies and independent, peer-reviewed journal trials undertaken after 2007 have since validated the safe use of UCAs. In addition, the agents contain no radioactive material or dye, present no known risk of kidney or liver damage, do not require sedation, and can be metabolized and expelled from body within minutes.
“Our collective experience shows that UCAs are exceedingly safe and beneficial, and they can change patient outcomes and improve patient experiences,” said the Society of Radiologists in Ultrasound in a statement, adding that contrast-enhanced ultrasound is often “equivalent to or superior to CT and MRI, yet it is less expensive, more patient-friendly, more widely available, and completely radiation-free.”
Echoing this sentiment is the ICUS. “If an initial ultrasound scan is done and the image is too grainy, that patient may be referred for alternative imaging such as CT, MR or PET. Typically, there are long waits for those forms of imaging,” said the spokesperson. “If you inject an ultrasound contrast agent, which flows through the bloodstream with the red blood cells and lights up the image, it makes the image clearer and allows you to see things you would not be able to see with conventional ultrasound alone. That can salvage a non-diagnostic ultrasound scan so it may not be necessary to subject patients to what could be redundant, unnecessary, more expensive, and potentially riskier imaging.”
Medical societies supporting the ICUS Petition include the American Institute of Ultrasound in Medicine (AIUM), the World Federation of Ultrasound in Medicine and Biology (WFUMB), the Society of Radiologists in Ultrasound (SRU), the Society of Diagnostic Medical Sonography (SDMS), the Society for Pediatric Radiology (SPR), the American Society of Echocardiography (ASE), and the Liver Imaging Reporting and Data System (LI-RADS) contrast-enhanced ultrasound (CEUS) working group.
