|AGREEMENT STATE REPORT - MEDICAL EVENT
The following was received via email:
"On 6/30/20 microspheres were injected in the patient [intended target of Hepatic Segments 4 through 8] at the vessel branch point with the intention of targeting both the right hepatic artery (RHA) and the middle hepatic artery (MHA). However, post-therapy imaging demonstrates that radiotracer was preferentially deposited along the MHA distribution. This is attributed to unforeseeable clumping of microspheres at the origin of the RHA, such that a majority of the microspheres were preferentially injected into MHA. As such, microspheres were predominantly deposited in the extrahepatic lymph node as well as an unexpected pancreaticoduodenal lymph node. Deposition in this second node can be attributed to additional unintended reflux into a third branching vessel upstream from the RHA and MHA, and further supports the assertion flow into the RHA was hindered by the clumping of microsphere particles. Ultimately, SPECT-CT image analysis suggests no more than approximately 40 percent of the therapy dose was deposited within the liver (as detailed below).
"It is estimated the following activity distribution from post-treatment imaging: At most, approximately 40 percent of the administered activity appears to be within the liver, with the other 60 percent being in extrahepatic tissue (e.g. lymph nodes). This breakdown should be considered approximate, as these images are not scatter corrected.
"From pre-treatment macro aggregated albumin (MAA) imaging, it appears that 84 percent of the administered activity was expected to be delivered to the liver, and 16 percent was expected to shunted to the nodes. Overall, this indicates that approximately 53 percent less activity than what was intended reached the liver. There is uncertainty in this estimate.
"The dose to extrahepatic tissue (lymph nodes) differs from what was intended/expected by more than 50 Rem (0.5 Gy)."
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.