Diagnostic radiopharmaceuticals are not pure gamma emitters. They also emit conversion and Auger electrons or positrons that can result in high doses to the tissue if the radiopharmaceutical is extravasated. These tissue doses can be as high as tissue doses from extravasated therapeutic radiopharmaceuticals.

Because of the small volume of radiopharmaceutical and saline typically administered during diagnostic procedures, no visible swelling or firmness at the injection site would be expected. Radiopharmaceuticals are usually non-vesicants and will not cause pain upon extravasation.

The process of tissue injury due to ionizing radiation may take weeks to years to appear depending on the tissue and the absorbed radiation dose. For some extravasations, it is likely that underlying tissue will absorb significantly more dose than the skin.

Also, there is conclusive evidence that extravasations are due to tools, training, and technique used during the administration of radiopharmaceuticals. They are not the fault of the patient.

The NRC is the federal agency responsible for regulating the medical use of isotopes and for the accurate administrations of radioactive material. The NRC has rejected the opinions that they should not protect patients from unintentional doses of radiation. Furthermore, a medical event does not necessarily mean that a patient has been harmed. The NRC has stated repeatedly: “A Medical Event may indicate potential problems in a medical facility’s use of radioactive materials. It does not necessarily result in harm to the patient.”

Over the past 40 years, nuclear medicine providers have failed to reduce the incidence of extravasation through internal means and it is unlikely that the community will fix this problem voluntarily. Additionally, accreditation organizations (ACR, IAC, and the Joint Commission) have no requirements related to extravasations in nuclear medicine.

Nuclear medicine professionals state that tissue doses >1.0 sievert can result in adverse tissue reactions. But they do not believe that diagnostic extravasations can reach this dose level, because they have never seen patients harmed. However, these professionals do not routinely measure extravasations and follow these patients for the appropriate amount of time (sometimes many years). Thirty-eight cases submitted to the NRC show doses can easily exceed 1.0 sievert and in the three published cases where extravasations were measured and patients followed, all experienced adverse tissue reactions.

While the four nuclear medicine societies confirm that extravasations can negatively affect image quality and quantification, many nuclear medicine professionals still don’t think image quality and quantification are issues that harm patients. The literature is clear on this point—extravasations can result in inappropriate care.

Many comments suggest that patients should not be told when they are significantly extravasated. This belief is inconsistent with the practice of modern medicine; patients want to know about information that can affect their care and need to be informed.