Imaging of brain tumors with L-3-[123I]iodo-alpha-methyl tyrosine and SPECT.

Carbon-11-labeled amino acids have been successfully used to image brain tumors by PET. This study was undertaken to evaluate the potential of L-3-[123I]-iodo-alpha-methyl tyrosine (123IMT) for metabolic imaging of brain tumors. Ten patients (glioblastoma, oligodendroglioma, lymphoma, and metastases) had early and delayed brain SPECT with a rotating gamma camera after i.v.-injection of 200-300 MBq 123IMT. In nine patients the tumors showed intense uptake of the radiotracer. Tumor-to-brain tissue ratios were between 1.4 and 2.6. 123IMT shows potentials for monitoring the effects of brain tumor therapy.

[A procedure for taking into account scattered radiation and scattered light in the densitometric determination of intravascular iodine content]. / Ein Verfahren zur Berücksichtigung von Streustrahlung und Streulicht bei densitometrischer Bestimmung des intravasalen Jodgehaltes.

Scattered light and scattered radiation are two significant sources of error during video densitometry and lead to local under-estimation of iodine concentration. A procedure is described using digital subtraction angiography which largely eliminates both factors. The measured intravascular iodine concentration is close to the true value throughout the entire intensifier field and quantitative evaluation is independent of local factors. The reduction of the artifacts improves diagnostic certainty during visual evaluation also.