Abstract
This report describes a comparative study between technetium-99m ethyl cysteinate dimer (ECD) and 99mTc-hexamethylpropylene amine oxime (HMPAO) in five neurological patients. The conversion kinetics of the tracers in the blood from forms capable of diffusion across the blood-brain barrier to non-diffusible forms were studied by arterial sampling and rapid octanol extraction. We observed that HMPAO has a faster conversion rate in the blood but that the fraction of the injected dose available for brain extraction is higher than in the case of ECD. Regional brain concentrations of the tracers were measured with single-photon emission tomography (SPET) 35 min and 60 min after the injection and remained stable within this interval. On the basis of the measurements of the arterial input and of SPET brain concentrations of the tracers, the regional steadystate influx constants (Ki in ml/min/g) were determined for several brain regions. In the grey matter the Ki values were (mean ± SD) 0.32 ± 0.03 and 0.35 ± 0.04 for HMPAO and ECD, respectively; in the white matter the values were 0.23 ± 0.01 and 0.23 ± 0.02, respectively. The Ki values of the two tracers in corresponding regions were closely correlated (P<0.001). The correspondence of the Ki values of ECD and HMPAO demonstrates that ECD can also be considered a tracer that may be used for quantitative measurements of brain perfusion.
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Kanno I, Lassen NA. Two methods for calculating regional cerebral blood flow from emission computed tomography of inert gas concentration. J Comput Assist Tomogr 1979; 3: 71–76
Kuhl DE, Barrio JR, Huang S et al. Quantifying local cerebral blood flow by N-isopropyl-p-[123I] iodoamphetamine (IMP) tomography. J Nucl Med 1982; 23: 196–203
Neirinckx RD, Canning LR, Piper IM et al. [99mTc] d, l-HMPAO: A new radiopharmaceutical for SPECT imaging of regional cerebral blood perfusion. J Nucl Med 1987; 28: 191–202
Andersen AR. 99mTc-D, L-Hexamethylene-propyleneamine oxime (99mTc-HMPAO): basic kinetic studies of a tracer of cerebral blood flow. Cerebrovasc Brain Metab Rev 1989; 1: 288–318
Lassen NA, Andersen AR, Friberg L, Paulson OB. The retention of [99mTc]-d, l-HMPAO in the human brain after intracarotid bolus injection: a kinetic analysis. J Cereb Blood Flow Metab 1988; 8: S13-S22
Matsuda H, Oba H, Seki H et al. Determination of flow and rate constants in a kinetic model of [99mTc]-hexamethyl-propylene amine oxime in the human brain. J Cereb Blood Flow Metab 1988; 8: S61-S68
Pupi A, De Cristofaro MTR, Bacciottini L et al. An analysis of the arterial input curve for technetium-99m-HMPAO: quantification of rCBF using single-photon emission computed tomography. J Nucl Med 1991; 32: 1501–1506
Murase K, Tanada S, Fujita H, Sakaki A, Hamamoto K. Kinetic behaviour of technetium-99m-HMPAO in the human brain and quantification of cerebral blood flow using dynamic SPECT. J Nucl Med 1992; 33: 135–143
Walovitch RC, Franceschi M, Picard M et al. Metabolism of 99mTc-l, l-ethyl cysteinate dimer in healthy volunteers. Neuropharmacology 1991; 30: 283–292
Vallabhajosula S, Zimmerman RE, Picard M et al. Technetium-99m ECD: a new brain imaging agent: in vivo kinetics and biodistribution studies in normal human subjects. J Nucl Med 1989; 30: 599–604
Greenberg JH, Araki N, Karp A, Reivich M. Quantitative measurement of regional cerebral ischemia using Tc-99m ECD. J Nucl Med 1991; 32: 1070
Castagnoli A, Borsato N, Bruno A et al. SPECT brain imaging in chronic stroke and dementia: a comparison of 99mTc-ECD and (99mTc-HMPAO): In: Hartmmann A, Kuschinsky W Hoyer S, eds. Cerebral ischemia and dementia. Berlin Heidelberg New York: Springer; 1991: 327–333
Léveillé J, Demonceau G, Walovitch RC. Intrasubject comparison between technetium-99m-ECD and technetium-99m-HMPAO in healthy human subjects. J Nucl Med 1992; 33: 480–484
Nakagawara J, Nakamura J, Takeda R et al. Clinical comparison between Tc-99m ECD and 1231-IMP SPECT images in patients with cerebrovascular disease. J Cereb Blood Flow Metab 1991; 11: S31
Suzuki S, Sakai F, Akutsu T, Tazaki Y. Tracer kinetics of 123I-IMP, Tc-99m-HM-PAO and Tc-99m-ECD: measurements of temporal changes in arterial and jugular venous radioactivity. J Cereb Blood Flow Metab 1991; 11: S774
Tanada S, Kurase K, Inoue T et al. In vivo comparison of intracerebral behaviour of Tc-99m labeled ECD with Tc-99m labeled HMPAO using dynamic brain SPECT and a compartment model analysis. J Cereb Blood Flow Metab 1991; 11: S769
Bacciottini L, Lunghi F, Pupi A et al. Evaluation of technetium 99m cyclobutylpropylene amine oxime as a potential brain perfusion imaging agent for SPET. Eur J Nucl Med 1990; 17: 242–247
Oh TE, Davis NJ. Radial artery cannulation. Anaesth Intensive Care 1975; 3: 12–18
Formiconi AR, Pupi A, Passeri A. Compensation of spatial system response in SPECT with conjugate gradient reconstruction technique. Phys Med Biol 1989; 34: 69–84
Formiconi AR. Oblique angle sections in emission computed tomography. J Nucl Med Allied Sci 1984; 28: 109–114
De Cristofaro MTR, Mascalchi M, Pupi A et al. Subcortical arteriosclerotic encephalopathy: single photon emission computed tomography-magnetic resonance imaging correlation. Am J Physiol Imaging 1990; 5: 68–74
Formiconi AR, Pupi A, De Cristofaro MTR et al. Superimposition of brain sections from different acquisition techniques (CT and SPECT). J Cereb Blood Flow Metab 1989; 9: S413
Pupi A, De Cristofaro MTR, Formiconi AR, et al. A brain phantom for studying contrast recovery in emission computerized tomography. Eur J Nucl Med 1990; 17: 15–20
Frackowiak RSJ, Lenzi GL, Jones T, Heather JD. Quantitative measurement of regional cerebral blood flow and oxygen metabolism in man using 15O and positron emission tomography: theory, procedure, and normal values. J Comput Assist Tomogr 1980; 4: 727–736
Levine R, Sunderland JJ, Lagreze HL et al. Cerebral perfusion reserve indexes determined by fluoromethane positron emission scanning. Stroke 1988; 19: 19–27
Rapoport SI. Positron emission tomography in Alzheimer's disease in relation to disease pathogenesis: a critical review. Cerebrovasc Brain Metab Rev 1991; 3: 297–335
Leblanc R. Physiologic studies of cerebral ischemia. Clin Neurosurg 1991; 37: 289–311
Kuwert T, Hennerici M, Langen KJ et al. Compensatory mechanism in patients with asymptomatic carotid artery occlusion. Neurol Res 1990; 12: 89–93
Maurer AH. Nuclear medicine: SPECT comparisons to PET. Radiol Clin North Am 1988; 26: 1059–1074
Rattner Z, Smith EO, Woods S, Dey H, Hoffer PB. Toward absolute quantitation of cerebral blood flow using technetium-99m-HMPAO and a single scan. J Nucl Med 1991; 32: 1506–1507
Holm S, Madsen PL, Rubin P, et al. Tc-99m HMPAO activation studies: validation of the split-dose, image subtraction approach. J Cereb Blood Flow Metab 1991; 11: S766
Andersen AR, Friberg H, Lassen NA et al. Assessment of the arterial input curve for [99mTc]-d, l-HM-PAO by rapid octanol extraction. J Cereb Blood Flow Metab 1988; 8: S23-S30
Léveillé J, Demonceau G, De Roo M et al. Characterization of technetium-99m-L,L-ECD for brain perfusion imaging. Part 2. Biodistribution and brain imaging in humans. J Nucl Med 1989; 30: 1902–1910
Holman BL, Hellman RS, Goldsmith SJ et al. Biodistribution, dosimetry and clinical evaluation of a technetium-99m ethyl cisteinate dimer in normal subjects and in patients with chronic cerebral infarction. J Nucl Med 1989; 30: 1018–1024
Di Rocco RJ, Silva DA, Kuczynski BL et al. The single-pass cerebral extraction and capillary permeability-surface area product of several putative cerebral blood flow imaging agents. J Nucl Med 1993; 34: 641–648
Budinger TF, Derenzo SE, Greenberg WL, Gullberg GT. Quantitative potentials of dynamic emission computed tomography. J Nucl Med 1978; 19: 309–315
Correia J. A bloody future for clinical PET? J Nucl Med 1992; 32: 620–622
Bradbury MWB, Kleeman CR. Stability of the potassium content of cerebrospinal fluid and brain. Am J Physiol 1967; 213: 519–528
Patlak CS, Blasberg RG, Fenstermacher JD. Graphical evaluation of blood-to-brain transfer constants from multiple-time uptake data. J Cereb Blood Flow Metab 1983; 3: 1–7
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Pupi, A., Castagnoli, A., De Cristofaro, M.T.R. et al. Quantitative comparison between 99mTc-HMPAO and 99mTc-ECD: measurement of arterial input and brain retention. Eur J Nucl Med 21, 124–130 (1994). https://doi.org/10.1007/BF00175759
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DOI: https://doi.org/10.1007/BF00175759