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Jakob Korf - One of the best experts on this subject based on the ideXlab platform.

  • Cobalt-57 as a SPET tracer in the visualization of ischaemic brain damage in patients with middle cerebral artery stroke
    Nuclear Medicine Communications, 1998
    Co-Authors: H Stevens, H. M. L. Jansen, Da Piers, C. Van De Wiele, J. De Reuck, S Knollema, Aej De Jager, Rudi Dierckx, Jakob Korf
    Abstract:

    In PET studies we have shown the usefulness of Cobalt radionuclides for the visualization and quantification of ischaemic damage in stroke. In the present study, we explored Co-57(2+) as a SPET tracer. Uptake of radioactivity was estimated by using a Cobalt enhancement ratio defined as the ratio of Cobalt uptake in the affected region versus a similar volume in the non-affected contralateral side. Clinical status was assessed with the Orgogozo stroke score at the time of scanning and at least 60 days after admission. Nineteen patients (11 men, 8 women) with a middle cerebral artery stroke were examined with Co-57(2+) SPET 0-30 days after stroke onset. Our investigations show enhanced Cobalt uptake in the infarcted brain tissue in patients with a major stroke and little clinical improvement. There was a significant correlation between the Cobalt enhancement ratio and the Orgogozo score at the time of scanning and discharge. Our results suggest that Co-57(2+) SPET is suitable for determining the extent of (possibly calcium-mediated) damage in stroke and in the assessment of potential therapeutic interventions. ((C) 1998 Lippincoft-Raven Publishers).

  • Cobalt-57 and technetium-99m-HMPAO-labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p

  • Cobalt 57 and technetium 99m hmpao labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p <0.05). Both the LER and the CER correlated significantly (p <0.05) with the Orgogozo score at the time of scanning. Only the LER correlated significantly (p <0.05) with the Orgogozo score at discharge. Conclusion: Uptake of Cobalt and leukocytes in the peri-infarct tissue suggests that Co-57 may visualize a component of the inflammatory response. Divalent Co-57 may be convenient to predict clinical prognosis after stroke.

  • Pharmacokinetics and Dosimetry of Cobalt-55 and Cobalt-57
    The Journal of Nuclear Medicine, 1996
    Co-Authors: H. M. L. Jansen, Jakob Korf, S Knollema, L. Veenma Van Der Duin, Antonius Willemsen, A. Wiersma Van Tilburg, Eric J.f. Franssen, Frans G. M. Russel, Anne M. J. Paans
    Abstract:

    The isotopes Co-55 and Co-57 have been evaluated for PET and SPECT imaging in several clinical brain studies. For clinical application of Cobalt, it is important to know the delivered radiation dose. The biodistribution of Co-55 in both rat and humans after intravenous (bolus)-administration was studied. Based on pharmacokinetic data, radiation dose calculations according to the MIRD system are presented, By combining present measurements with literature data on (CoCl2)-Co-60, the radiation dose delivered by (CoCl2)-Co-56 (T-1/2 78.8 days) and (CoCl2)-Co-57 (T-1/2 = 270 days) could be assessed. Methods: Whole-body Co-PET was performed in two healthy volunteers and one rat after intravenous injection of 37 and 3.7 MBq (1 resp, 0.1 mCl) Co-55, respectively. Blood samples were withdrawn during 300 min in humans. In seven rats the Co-55-biodistribution was determined by postmortem analysis. The residence time of the liver (critical organ) was determined in rats and humans. Blood partition-data of Co-55 were assessed resulting in basic pharmacokinetic data in humans. Based on these kinetic data, radiation dose was calculated using the MIRD protocol. Results: In both the humans and the rat, the liver and bladder retained the highest fractions of Co-55 (about 50% resp. 40% of the administered dose), The liver residence time in humans was 8.6 hr. The free fraction Co-55 in the human plasma was at maximum 12%. The total-body mean transit time was 152 min. The volume of the central compartment = 2.8 liter and the steady-state distribution volume = 48 liter. Conclusion: From these results, according to the WHO recommendations for class II studies, 22.2 MBq (0.6 mCi) Co-55 and 14.8 MBq (0.4 mCi) Co-57 (excluding any radionuclide contamination) can be used.

H Stevens - One of the best experts on this subject based on the ideXlab platform.

  • Cobalt-57 as a SPET tracer in the visualization of ischaemic brain damage in patients with middle cerebral artery stroke
    Nuclear Medicine Communications, 1998
    Co-Authors: H Stevens, H. M. L. Jansen, Da Piers, C. Van De Wiele, J. De Reuck, S Knollema, Aej De Jager, Rudi Dierckx, Jakob Korf
    Abstract:

    In PET studies we have shown the usefulness of Cobalt radionuclides for the visualization and quantification of ischaemic damage in stroke. In the present study, we explored Co-57(2+) as a SPET tracer. Uptake of radioactivity was estimated by using a Cobalt enhancement ratio defined as the ratio of Cobalt uptake in the affected region versus a similar volume in the non-affected contralateral side. Clinical status was assessed with the Orgogozo stroke score at the time of scanning and at least 60 days after admission. Nineteen patients (11 men, 8 women) with a middle cerebral artery stroke were examined with Co-57(2+) SPET 0-30 days after stroke onset. Our investigations show enhanced Cobalt uptake in the infarcted brain tissue in patients with a major stroke and little clinical improvement. There was a significant correlation between the Cobalt enhancement ratio and the Orgogozo score at the time of scanning and discharge. Our results suggest that Co-57(2+) SPET is suitable for determining the extent of (possibly calcium-mediated) damage in stroke and in the assessment of potential therapeutic interventions. ((C) 1998 Lippincoft-Raven Publishers).

  • Cobalt-57 and technetium-99m-HMPAO-labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p

  • Cobalt 57 and technetium 99m hmpao labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p <0.05). Both the LER and the CER correlated significantly (p <0.05) with the Orgogozo score at the time of scanning. Only the LER correlated significantly (p <0.05) with the Orgogozo score at discharge. Conclusion: Uptake of Cobalt and leukocytes in the peri-infarct tissue suggests that Co-57 may visualize a component of the inflammatory response. Divalent Co-57 may be convenient to predict clinical prognosis after stroke.

C. Van De Wiele - One of the best experts on this subject based on the ideXlab platform.

  • Cobalt-57 as a SPET tracer in the visualization of ischaemic brain damage in patients with middle cerebral artery stroke
    Nuclear Medicine Communications, 1998
    Co-Authors: H Stevens, H. M. L. Jansen, Da Piers, C. Van De Wiele, J. De Reuck, S Knollema, Aej De Jager, Rudi Dierckx, Jakob Korf
    Abstract:

    In PET studies we have shown the usefulness of Cobalt radionuclides for the visualization and quantification of ischaemic damage in stroke. In the present study, we explored Co-57(2+) as a SPET tracer. Uptake of radioactivity was estimated by using a Cobalt enhancement ratio defined as the ratio of Cobalt uptake in the affected region versus a similar volume in the non-affected contralateral side. Clinical status was assessed with the Orgogozo stroke score at the time of scanning and at least 60 days after admission. Nineteen patients (11 men, 8 women) with a middle cerebral artery stroke were examined with Co-57(2+) SPET 0-30 days after stroke onset. Our investigations show enhanced Cobalt uptake in the infarcted brain tissue in patients with a major stroke and little clinical improvement. There was a significant correlation between the Cobalt enhancement ratio and the Orgogozo score at the time of scanning and discharge. Our results suggest that Co-57(2+) SPET is suitable for determining the extent of (possibly calcium-mediated) damage in stroke and in the assessment of potential therapeutic interventions. ((C) 1998 Lippincoft-Raven Publishers).

  • Cobalt-57 and technetium-99m-HMPAO-labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p

  • Cobalt 57 and technetium 99m hmpao labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p <0.05). Both the LER and the CER correlated significantly (p <0.05) with the Orgogozo score at the time of scanning. Only the LER correlated significantly (p <0.05) with the Orgogozo score at discharge. Conclusion: Uptake of Cobalt and leukocytes in the peri-infarct tissue suggests that Co-57 may visualize a component of the inflammatory response. Divalent Co-57 may be convenient to predict clinical prognosis after stroke.

J. De Reuck - One of the best experts on this subject based on the ideXlab platform.

  • Cobalt-57 as a SPET tracer in the visualization of ischaemic brain damage in patients with middle cerebral artery stroke
    Nuclear Medicine Communications, 1998
    Co-Authors: H Stevens, H. M. L. Jansen, Da Piers, C. Van De Wiele, J. De Reuck, S Knollema, Aej De Jager, Rudi Dierckx, Jakob Korf
    Abstract:

    In PET studies we have shown the usefulness of Cobalt radionuclides for the visualization and quantification of ischaemic damage in stroke. In the present study, we explored Co-57(2+) as a SPET tracer. Uptake of radioactivity was estimated by using a Cobalt enhancement ratio defined as the ratio of Cobalt uptake in the affected region versus a similar volume in the non-affected contralateral side. Clinical status was assessed with the Orgogozo stroke score at the time of scanning and at least 60 days after admission. Nineteen patients (11 men, 8 women) with a middle cerebral artery stroke were examined with Co-57(2+) SPET 0-30 days after stroke onset. Our investigations show enhanced Cobalt uptake in the infarcted brain tissue in patients with a major stroke and little clinical improvement. There was a significant correlation between the Cobalt enhancement ratio and the Orgogozo score at the time of scanning and discharge. Our results suggest that Co-57(2+) SPET is suitable for determining the extent of (possibly calcium-mediated) damage in stroke and in the assessment of potential therapeutic interventions. ((C) 1998 Lippincoft-Raven Publishers).

  • Cobalt-57 and technetium-99m-HMPAO-labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p

  • Cobalt 57 and technetium 99m hmpao labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p <0.05). Both the LER and the CER correlated significantly (p <0.05) with the Orgogozo score at the time of scanning. Only the LER correlated significantly (p <0.05) with the Orgogozo score at discharge. Conclusion: Uptake of Cobalt and leukocytes in the peri-infarct tissue suggests that Co-57 may visualize a component of the inflammatory response. Divalent Co-57 may be convenient to predict clinical prognosis after stroke.

Patrick Santens - One of the best experts on this subject based on the ideXlab platform.

  • Cobalt-57 and technetium-99m-HMPAO-labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p

  • Cobalt 57 and technetium 99m hmpao labeled leukocytes for visualization of ischemic infarcts
    The Journal of Nuclear Medicine, 1998
    Co-Authors: H Stevens, C. Van De Wiele, Patrick Santens, H. Jansen, J. De Reuck, R. A. J. O. Dierckx, Jakob Korf
    Abstract:

    Previous studies have shown the usefulness of divalent Cobalt isotopes to visualize cerebral damage after stroke, The site of accumulation of Cobalt ion is unknown but may be explained by neuronal influx, analogous to that of calcium ion. Additionally, uptake may be due to infiltrating leukocytes or protein-bound Cobalt. The aims of this study were to compare Co-57-SPECT with leukocyte SPECT and to compare the SPECT findings with clinical outcome as scored by the Orgogozo scale. Materials: Ten patients with a CT scan positive for middle cerebral artery infarcts were included in the study (7 men, 3 women; mean age 70 yr), Technetium-99m leukocyte and Cobalt-SPECT (interval 2-4 days) were made with a double-headed gamma camera, after the injection of 10-15 mCi Tc-99m-HMPAO-labeled leukocytes and 0.4 mCi Co-57, respectively, Scans were performed within 5-30 days after onset of the first symptoms. Regions of interest (ROI) containing the area of infarction in the slices displaying enhanced radioactivity or the middle cerebral artery (MCA) region in four successive slices were defined for calculating enhancement ratios. The (TC)-T-99m leukocyte enhancement ratio (LER) and Cobalt enhancement ratio (CER) were defined as the quotient of radioactivity in the ROI and an identical contralateral ROI. The MCA stroke-scale according to Orgogozo was used to assess neurological deficits at the time of scanning and discharge. Results: Cobalt-57 and Tc-99m-HMPAO showed uptake in the infarcted brain area in five patients; the quantitative uptake in the infarcted brain area of the two tracers correlated significantly (p <0.05). Both the LER and the CER correlated significantly (p <0.05) with the Orgogozo score at the time of scanning. Only the LER correlated significantly (p <0.05) with the Orgogozo score at discharge. Conclusion: Uptake of Cobalt and leukocytes in the peri-infarct tissue suggests that Co-57 may visualize a component of the inflammatory response. Divalent Co-57 may be convenient to predict clinical prognosis after stroke.