Limits...
Targeting murine heart and brain: visualisation conditions for multi-pinhole SPECT with (99m)Tc- and (123)I-labelled probes.

Pissarek M, Meyer-Kirchrath J, Hohlfeld T, Vollmar S, Oros-Peusquens AM, Flögel U, Jacoby C, Krügel U, Schramm N - Eur. J. Nucl. Med. Mol. Imaging (2009)

Bottom Line: Alterations of maximal cerebral uptake of [(123)I]IBZM by >20% (116 kBq) were verified with the prerequisite of 50% striatal of total uptake.The labelling with [(99m)Tc]sestamibi revealed a 30% lower uptake in cardiomyopathic hearts compared to wild types. [(123)I]IPPA uptake could be visualised at activity doses of 0.8 MBq/g body weight.The thresholds of detection for differences in the tracer uptake determined under the conditions of our experiments well reflect distinctions in molar activity and uptake characteristics of the tracers.

View Article: PubMed Central - PubMed

Affiliation: Institute of Neurosciences and Biophysics-Nuclear Chemistry (INB-4), Research Centre Juelich, Leo-Brandt-Str., 52428, Juelich, Germany. m.pissarek@fz-juelich.de

ABSTRACT

Purpose: The study serves to optimise conditions for multi-pinhole SPECT small animal imaging of (123)I- and (99m)Tc-labelled radiopharmaceuticals with different distributions in murine heart and brain and to investigate detection and dose range thresholds for verification of differences in tracer uptake.

Methods: A Triad 88/Trionix system with three 6-pinhole collimators was used for investigation of dose requirements for imaging of the dopamine D(2) receptor ligand [(123)I]IBZM and the cerebral perfusion tracer [(99m)Tc]HMPAO (1.2-0.4 MBq/g body weight) in healthy mice. The fatty acid [(123)I]IPPA (0.94 +/- 0.05 MBq/g body weight) and the perfusion tracer [(99m)Tc]sestamibi (3.8 +/- 0.45 MBq/g body weight) were applied to cardiomyopathic mice overexpressing the prostaglandin EP(3) receptor.

Results: In vivo imaging and in vitro data revealed 45 kBq total cerebral uptake and 201 kBq cardiac uptake as thresholds for visualisation of striatal [(123)I]IBZM and of cardiac [(99m)Tc]sestamibi using 100 and 150 s acquisition time, respectively. Alterations of maximal cerebral uptake of [(123)I]IBZM by >20% (116 kBq) were verified with the prerequisite of 50% striatal of total uptake. The labelling with [(99m)Tc]sestamibi revealed a 30% lower uptake in cardiomyopathic hearts compared to wild types. [(123)I]IPPA uptake could be visualised at activity doses of 0.8 MBq/g body weight.

Conclusion: Multi-pinhole SPECT enables detection of alterations of the cerebral uptake of (123)I- and (99m)Tc-labelled tracers in an appropriate dose range in murine models targeting physiological processes in brain and heart. The thresholds of detection for differences in the tracer uptake determined under the conditions of our experiments well reflect distinctions in molar activity and uptake characteristics of the tracers.

Show MeSH

Related in: MedlinePlus

Uptake of [99mTc]HMPAO in the murine brain. [99mTc]HMPAO uptake after application of 0.47 (A) and 1.16 MBq/g body weight (B). The body weight of the animals was 36 g. Acquisition time of 140 s and 10 steps of rotation were used for imaging. 1 thyroid gland, 2 salivary gland, 3 lacrimal gland and ducts. Planes of the sections: a coronal, b transversal, c sagittal. Sections Aa and Ba were measured at prone position of the animals, however, are shown here in supine position
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2724637&req=5

Fig7: Uptake of [99mTc]HMPAO in the murine brain. [99mTc]HMPAO uptake after application of 0.47 (A) and 1.16 MBq/g body weight (B). The body weight of the animals was 36 g. Acquisition time of 140 s and 10 steps of rotation were used for imaging. 1 thyroid gland, 2 salivary gland, 3 lacrimal gland and ducts. Planes of the sections: a coronal, b transversal, c sagittal. Sections Aa and Ba were measured at prone position of the animals, however, are shown here in supine position

Mentions: Figure 7 shows [99mTc]HMPAO SPECT images. The tracer allows a visualisation of brain perfusion using an activity of 1.16 MBq/g even at an acquisition time of 140 s but not using half of that activity (for maximum intensity projections of [123I]IBZM and [99mTc]HMPAO SPECT see Supplement 1A and Supplement 1B, respectively).Fig. 7


Targeting murine heart and brain: visualisation conditions for multi-pinhole SPECT with (99m)Tc- and (123)I-labelled probes.

Pissarek M, Meyer-Kirchrath J, Hohlfeld T, Vollmar S, Oros-Peusquens AM, Flögel U, Jacoby C, Krügel U, Schramm N - Eur. J. Nucl. Med. Mol. Imaging (2009)

Uptake of [99mTc]HMPAO in the murine brain. [99mTc]HMPAO uptake after application of 0.47 (A) and 1.16 MBq/g body weight (B). The body weight of the animals was 36 g. Acquisition time of 140 s and 10 steps of rotation were used for imaging. 1 thyroid gland, 2 salivary gland, 3 lacrimal gland and ducts. Planes of the sections: a coronal, b transversal, c sagittal. Sections Aa and Ba were measured at prone position of the animals, however, are shown here in supine position
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2724637&req=5

Fig7: Uptake of [99mTc]HMPAO in the murine brain. [99mTc]HMPAO uptake after application of 0.47 (A) and 1.16 MBq/g body weight (B). The body weight of the animals was 36 g. Acquisition time of 140 s and 10 steps of rotation were used for imaging. 1 thyroid gland, 2 salivary gland, 3 lacrimal gland and ducts. Planes of the sections: a coronal, b transversal, c sagittal. Sections Aa and Ba were measured at prone position of the animals, however, are shown here in supine position
Mentions: Figure 7 shows [99mTc]HMPAO SPECT images. The tracer allows a visualisation of brain perfusion using an activity of 1.16 MBq/g even at an acquisition time of 140 s but not using half of that activity (for maximum intensity projections of [123I]IBZM and [99mTc]HMPAO SPECT see Supplement 1A and Supplement 1B, respectively).Fig. 7

Bottom Line: Alterations of maximal cerebral uptake of [(123)I]IBZM by >20% (116 kBq) were verified with the prerequisite of 50% striatal of total uptake.The labelling with [(99m)Tc]sestamibi revealed a 30% lower uptake in cardiomyopathic hearts compared to wild types. [(123)I]IPPA uptake could be visualised at activity doses of 0.8 MBq/g body weight.The thresholds of detection for differences in the tracer uptake determined under the conditions of our experiments well reflect distinctions in molar activity and uptake characteristics of the tracers.

View Article: PubMed Central - PubMed

Affiliation: Institute of Neurosciences and Biophysics-Nuclear Chemistry (INB-4), Research Centre Juelich, Leo-Brandt-Str., 52428, Juelich, Germany. m.pissarek@fz-juelich.de

ABSTRACT

Purpose: The study serves to optimise conditions for multi-pinhole SPECT small animal imaging of (123)I- and (99m)Tc-labelled radiopharmaceuticals with different distributions in murine heart and brain and to investigate detection and dose range thresholds for verification of differences in tracer uptake.

Methods: A Triad 88/Trionix system with three 6-pinhole collimators was used for investigation of dose requirements for imaging of the dopamine D(2) receptor ligand [(123)I]IBZM and the cerebral perfusion tracer [(99m)Tc]HMPAO (1.2-0.4 MBq/g body weight) in healthy mice. The fatty acid [(123)I]IPPA (0.94 +/- 0.05 MBq/g body weight) and the perfusion tracer [(99m)Tc]sestamibi (3.8 +/- 0.45 MBq/g body weight) were applied to cardiomyopathic mice overexpressing the prostaglandin EP(3) receptor.

Results: In vivo imaging and in vitro data revealed 45 kBq total cerebral uptake and 201 kBq cardiac uptake as thresholds for visualisation of striatal [(123)I]IBZM and of cardiac [(99m)Tc]sestamibi using 100 and 150 s acquisition time, respectively. Alterations of maximal cerebral uptake of [(123)I]IBZM by >20% (116 kBq) were verified with the prerequisite of 50% striatal of total uptake. The labelling with [(99m)Tc]sestamibi revealed a 30% lower uptake in cardiomyopathic hearts compared to wild types. [(123)I]IPPA uptake could be visualised at activity doses of 0.8 MBq/g body weight.

Conclusion: Multi-pinhole SPECT enables detection of alterations of the cerebral uptake of (123)I- and (99m)Tc-labelled tracers in an appropriate dose range in murine models targeting physiological processes in brain and heart. The thresholds of detection for differences in the tracer uptake determined under the conditions of our experiments well reflect distinctions in molar activity and uptake characteristics of the tracers.

Show MeSH
Related in: MedlinePlus