[Phase I clinical study of 99mTc-ECD].
A phase I clinical study of 99mTc-L,L-ethyl cysteinate dimer (99mTc-ECD) was carried out in 3 normal volunteers. There was no significant change in vital signs and laboratory parameters attributing to the radiopharmaceutical. 99mTc-ECD was rapidly taken up by the brain, reaching the maximum peak activity within 1 min after the injection and remained relatively constant over several hours. The brain uptake of 99mTc-ECD at 5 min was 5.4 +/- 0.5% which decreased to 5.0 +/- 0.3% by 65 min. 99mTc-ECD cleared rapidly from other organs. The primary excretion route was through the kidneys. Cumulative 99mTc activity in the urine at 90 min and 24 hr were 60.2 +/- 7.3% and 88.5 +/- 10.3%, respectively. The critical organ was the bladder wall with an estimated radiation dose of 0.073 mGy/MBq, which was acceptable value. Clear SPECT images were obtained at 30, 90 and 150 min postinjection. In conclusion, 99mTc-ECD is a safe and promising radiopharmaceutical for the evaluation of regional cerebral blood flow.
Kubo
A
A
Department of Radiology, Keio University Hospital, Tokyo.
Nakamura
K
K
Tsukatani
Y
Y
Sanmiya
T
T
Shimizu
S
S
Yokoyama
K
K
Hashimoto
S
S
Torizuka
K
K
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D002560:Cerebrovascular Circulation; D003545:Cysteine / Q000031:analogs & derivatives*; D006801:Humans; D007668:Kidney / Q000378:metabolism; D008297:Male; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon; D001743:Urinary Bladder / Q000378:metabolism
D015609:Organotechnetium Compounds; C059659:technetium Tc 99m bicisate; D003545:Cysteine