Different uptake of 99mTc-ECD and 99mTc-HMPAO in the same brains: analysis by statistical parametric mapping

Abstract

The purpose of this study was to investigate the differences between technetium-99m ethyl cysteinate dimer (99mTc-ECD) and technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) uptake in the same brains by means of statistical parametric mapping (SPM) analysis. We examined 20 patients (9 male, 11 female, mean age 62+/-12 years) using 99mTc-ECD and 99mTc-HMPAO single-photon emission tomography (SPET) and magnetic resonance imaging (MRI) of the brain less than 7 days after onset of stroke. MRI showed no cortical infarctions. Infarctions in the pons (6 patients) and medulla (1), ischaemic periventricular white matter lesions (13) and lacunar infarction (7) were found on MRI. Split-dose and sequential SPET techniques were used for 99mTc-ECD and 99mTc-HMPAO brain SPET, without repositioning of the patient. All of the SPET images were spatially transformed to standard space, smoothed and globally normalized. The differences between the 99mTc-ECD and 99mTc-HMPAO SPET images were statistically analysed using statistical parametric mapping (SPM) 96 software. The difference between two groups was considered significant at a threshold of uncorrected P values less than 0.01. Visual analysis showed no hypoperfused areas on either 99mTc-ECD or 99mTc-HMPAO SPET images. SPM analysis revealed significantly different uptake of 99mTc-ECD and 99mTc-HMPAO in the same brains. On the 99mTc-ECD SPET images, relatively higher uptake was observed in the frontal, parietal and occipital lobes, in the left superior temporal lobe and in the superior region of the cerebellum. On the 99mTc-HMPAO SPET images, relatively higher uptake was observed in the medial temporal lobes, thalami, periventricular white matter and brain stem. These differences in uptake of the two tracers in the same brains on SPM analysis suggest that interpretation of cerebral perfusion is possible using SPET with 99mTc-ECD and 99mTc-HMPAO.

Cerebral Accumulation of TC-99M Ethyl Cysteinate Dimer (ECD) in Severe, Transient Hypothyroidism

“…Results from this and other groups (Jonsson et al, 1998) have demonstrated that both Tc-99m ECD and Tc-99m HMPAO fail to provide a precise map of cerebral perfusion. Discrepancies between the patterns seen with these different tracers in hypothyroid subjects is, in fact, not unexpected when one considers that Tc-99m ECD and Tc-99m HMPAO have been shown to demonstrate different patterns of accumulation in the same brains, both healthy and diseased (Hyun et al, 2001;Siennicki-Lantz et al, 1999;Komatani et al, 1998;Asenbaum et al, 1998).…”

Preclinical Evaluation of Drug-Eluting Stents for Peripheral Applications

“…PET or MRI, if available, can be used to measure brain perfusion in vivo, and radionuclide imaging also can be used with single photon emission computed tomography. 14,15 Histopathology of the brain should be examined for plaques, evidence of amyloid, neurofibrillary tangles and neuropil threads, and angiopathy including hemorrhage.…”

<b>A Higher Prevalence of Abnormal Regional Cerebral Blood Flow in Patients With Syndrome X and Abnormal Myocardial Perfusion</b>

“…On the Tc-99m HMPAO brain SPECT, relatively higher uptake was observed in the medial lobes, thalami, periventricular white matter, and brain stem. 18) Therefore, in the preliminary report, we used Tc-99m ECD brain SPECT to detect brain lesions in patients with syndrome X. In addition, our research is the first study to use Tc-99m ECD brain SPECT for diagnosing brain involvement in patients with syndrome X.…”