Comparison of parathyroid imaging with technetium-99m-pertechnetate/sestamibi subtraction, double-phase technetium-99m-sestamibi and technetium-99m-sestamibi SPECT.

Unlabelled: The ability of 99mTc-pertechnetate/sestamibi subtraction, double-phase 99mTc-sestamibi and 99mTc-sestamibi SPECT imaging to localize abnormal parathyroid tissue was compared.

Methods: Fifty-five consecutive patients had parathyroid imaging before surgery for hyperparathyroidism. Imaging consisted of 99mTc-pertechnetate pinhole images of the neck followed by 99mTc-sestamibi pinhole images of the neck and parallel-hole images of the neck and chest (early images).

Phantom evaluation of simultaneous thallium-201/technetium-99m aquisition in single-photon emission tomography.

This study investigated downscatter effects in cardiac single-photon emission tomographic studies with simultaneous thallium-201/technetium-99m acquisition, and evaluated a previously proposed subtraction technique for downscatter compensation. Ten studies were carried out with different defect sizes and locations and varying activity distributions using four energy windows: 70+/-10% keV, 140+/-10% keV, 100+/-10% KeV, and 103+/-16% keV. The subtraction technique used the 100- or 103-keV data to remove scattered 99mTc counts from the 70-keV data.

Measurement of blood volume with an enriched stable isotope of chromium (53Cr) and isotope dilution by combined gas chromatography-mass spectrometry.

We used an established isotope dilution gas chromatography-mass spectrometry method to measure blood volumes with an enriched stable isotope of chromium. The results were compared with those of the conventional method, which involves radioactive 51Cr. The two methods were compared simultaneously in two male subjects of different sizes, and essentially identical volumes were obtained.