These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Biodistribution and radiation dosimetry of the amyloid imaging agent 11C-PIB in humans.
    Author: Scheinin NM, Tolvanen TK, Wilson IA, Arponen EM, Någren KA, Rinne JO.
    Journal: J Nucl Med; 2007 Jan; 48(1):128-33. PubMed ID: 17204709.
    Abstract:
    UNLABELLED: We investigated the biodistribution and radiation dosimetry of the PET amyloid imaging agent (11)C-PIB ((11)C-6-OH-BTA-1) (where BTA is benzothiazole) in humans. Previous radiation exposure estimates have been based on animal experiments. A dosimetry study in humans is essential for a balanced risk-benefit assessment of (11)C-PIB PET studies. METHODS: We used data from 16 different (11)C-PIB PET scans on healthy volunteers to estimate radiation exposure. Six of these scans were dynamic imaging over the abdominal region: 3 covering the upper abdomen and 3 covering the middle abdomen. On average, 489 MBq of (11)C-PIB (range, 416-606 MBq) were injected intravenously, and dynamic emission scans were recorded for up to 40 min. Two subjects had whole-body imaging over the entire body to illustrate the biodistribution. PET brain scans and blood and urine radioactivity measurements from our previous (11)C-PIB studies were also analyzed. Thirteen source organs and the remainder of the body were studied to estimate residence times and mean radiation-absorbed doses. The MIRD method was used to calculate the radiation exposure of selected target organs and the body as a whole. RESULTS: There is a high degree of consistency between our human data and previous biodistribution information based on baboons. In our study, the highest radiation-absorbed doses were received by the gallbladder wall (41.5 microGy/MBq), liver (19.0 microGy/MBq), urinary bladder wall (16.6 microGy/MBq), kidneys (12.6 microGy/MBq), and upper large intestine wall (9.0 microGy/MBq). The hepatobiliary and renal systems were the major routes of clearance and excretion, with approximately 20% of the injected radioactivity being excreted into urine. The effective radiation dose was 4.74 microSv/MBq. CONCLUSION: The established clinical dose of (11)C-PIB required for 3-dimensional PET amyloid imaging has an acceptable effective radiation dose. This dose is comparable with the average exposure expected in other PET brain receptor tracer studies. (11)C-PIB is rapidly cleared from the body, largely by the kidneys. From the viewpoint of radiation safety, these results support the use of (11)C-PIB in clinical PET studies.
    [Abstract] [Full Text] [Related] [New Search]