No abstract available.
Abscess* ; Technetium Tc 99m Exametazime*

No abstract available.
Mucormycosis* ; Technetium Tc 99m Exametazime*

No abstract available.
Brain* ; Technetium Tc 99m Exametazime*

No abstract available.
Brain* ; Technetium Tc 99m Exametazime*

No abstract available.
Brain* ; Technetium Tc 99m Exametazime*

No abstract available.
Brain* ; Technetium Tc 99m Exametazime ; Tomography, Emission-Computed, Single-Photon*

No abstract available.
Ischemia* ; Technetium Tc 99m Exametazime* ; Tomography, Emission-Computed, Single-Photon*

Acetazolamide, a selective-inhibitor of carbonic anhydrase. Has been shown to induce a rapid increase in cerebral blood flow by acidifying cerebral extracellular tluid in large doses. In order to assess the cerebral blood flow reserve, we investigated 14 patients with ischemic cerebrovascular disease using Tc-99m HMPAO SPECT before and after administration of acetazolamide.The patients after acetazolamide challenge showed variable pattems of vasodilating capacity which were classified as follows: group I. Accentuation of abnormal perfusion pattem; group II, no change in abnormal perfusion pattern: and group III. Blunting of abnormal perfusion pattern. Thirty-six percent of the patients studied qualified for group I. The p?tients in group I seem to have decreased vasodilating reserve in the area of cerebral ischemia. They are most likely to benefit by medical or surgical efforts to augment CBF delivery. Tc-99m HMPAO-SPECT with acetazolamide flow challenge may serve as an objective. Clinically accessible method for assessing blood flow reserve and as a kind of guide for the therapeutic strategy.
Acetazolamide* ; Brain Ischemia ; Carbonic Anhydrases ; Humans ; Perfusion ; Technetium Tc 99m Exametazime ; Tomography, Emission-Computed, Single-Photon

PURPOSE: 99mTc-HMPAO is a radiopharmaceutical for imaging cerebral blood flow. HMPAO (RR, SS)-4,8- diaza-3,6,6,9-tetramethylundecan-2,10- dione bisoxime) has three stereoismers such as, meso-, d-, and l-HMPAO. Techentium complexes of meso-HMPAO and d,l-HMPAO are known to have different in vivo brain uptakes. In this study, enantiomers of HMPAO (d-HMPAO and l-HMPAO) were separated from d,l-HMPAO. These enantiomers were labeled with 99mTc and the biodistribution studies were performed in mice. MATERIALS AND METHODS: An intermediate imine product was produced from 2,3-butanedione monooxime and 2,2-dimethyl- 1,3-propanediamine (54% yield) and was reduced into a mixture of three isomers (35% yield). The meso-isomer was separated from d,l-mixture by repeated fractional crystallization (11% yield). The d- and l-enantiomers were subsequently separated by co-crystallization with optical isomers of tartaric acid (25% and 5% yield, respectively). Each enantiomeric HMPAO was labeled with 99mTc by reacting with SnCl2 2H2O and 99mTc-pertechnetate. Biodistribution study was performed 1 hr after tail vein injection to ICR mice. RESULTS: Radiochemical purities of each compound were over 80%. In biodistribution study, the brain uptakes of d,l- d- and l-form were 1.34, 1.12 and 1.67% ID/g, respectively. In case of l-Isomer the brain uptake was higher (1.5 fold) than d-isomer. CONCLUSION: We successfully purified each enantiomeric HMPAO. In biodistribution study of stereoismers of 99mTc-HMPAO in mice, l-HMPAO may show better brain image than d,l-HMPAO which was supplied in a commercial kit.
Animals ; Brain* ; Crystallization ; Dental Calculus ; Diacetyl ; Mice ; Mice, Inbred ICR ; Stereoisomerism ; Technetium Tc 99m Exametazime* ; Veins

No abstract available.
Brain* ; Technetium Tc 99m Exametazime* ; Thalamic Diseases* ; Tomography, Emission-Computed, Single-Photon*