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1.
Rev Neurol (Paris) ; 178(8): 826-844, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35623940

ABSTRACT

Brain plasticity can be defined as the ability of local and extended neural systems to organize either the structure and/or the function of their connectivity patterns to better adapt to changes of our inner/outer environment and optimally respond to new challenging behavioral demands. Plasticity has been traditionally conceived as a spontaneous phenomenon naturally occurring during pre and postnatal development, tied to learning and memory processes, or enabled following neural damage and their rehabilitation. Such effects can be easily observed and measured but remain hard to harness or to tame 'at will'. Non-invasive brain stimulation (NIBS) technologies offer the possibility to engage plastic phenomena, and use this ability to characterize the relationship between brain regions, networks and their functional connectivity patterns with cognitive process or disease symptoms, to estimate cortical malleability, and ultimately contribute to neuropsychiatric therapy and rehabilitation. NIBS technologies are unique tools in the field of fundamental and clinical research in humans. Nonetheless, their abilities (and also limitations) remain rather unknown and in the hands of a small community of experts, compared to widely established methods such as functional neuroimaging (fMRI) or electrophysiology (EEG, MEG). In the current review, we first introduce the features, mechanisms of action and operational principles of the two most widely used NIBS methods, Transcranial Magnetic Stimulation (TMS) and Transcranial Current Stimulation (tCS), for exploratory or therapeutic purposes, emphasizing their bearings on neural plasticity mechanisms. In a second step, we walk the reader through two examples of recent domains explored by our team to further emphasize the potential and limitations of NIBS to either explore or improve brain function in healthy individuals and neuropsychiatric populations. A final outlook will identify a series of future topics of interest that can foster progress in the field and achieve more effective manipulation of brain plasticity and interventions to explore and improve cognition and treat the symptoms of neuropsychiatric diseases.


Subject(s)
Neuronal Plasticity , Transcranial Magnetic Stimulation , Brain/diagnostic imaging , Humans , Magnetic Resonance Imaging , Neuronal Plasticity/physiology , Plastics , Transcranial Magnetic Stimulation/methods
2.
Rev Neurol (Paris) ; 177(9): 1090-1092, 2021 11.
Article in English | MEDLINE | ID: mdl-34772473
3.
Lett Appl Microbiol ; 53(1): 35-43, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21554343

ABSTRACT

AIMS: Oral administration of probiotics has been known to improve inflammatory responses against infectious diseases. Here, we describe the inhibitory effect of oral intake of heat-killed Lactobacillus pentosus strain b240 (b240) on pneumococcal pneumonia in a murine experimental model. METHOD AND RESULTS: The mice treated with oral b240 for 21 days before Streptococcus pneumoniae infection exhibited prolonged survival time and less body weight loss, compared with saline-treated control mice. Mild pneumonia with significantly reduced secretion of inflammatory cytokines/chemokines according to related mitogen-activated protein kinase signalling molecules (phosphorylated c-Jun N-terminal kinase) was found in b240-treated mice, whereas severe pneumonia with hypercytokinemia was evident in control mice. Prominent reduction in the number of pneumococci and elevated expression of Toll-like receptor 2 and 4 in the lung tissues was concomitantly noted in b240-treated mice. CONCLUSIONS: These findings indicate that b240 has inhibitory effects on pneumococcal pneumonia induced by Strep. pneumoniae infection and improves inflammatory tissue responses, resulting in reduced damages to the respiratory tissues. SIGNIFICANCE AND IMPACT OF THE STUDY: These results demonstrate that oral administration of b240 might protect host animals from Strep. pneumoniae infection by augmentation of innate immune response.


Subject(s)
Lactobacillus , Pneumonia, Pneumococcal/immunology , Probiotics/administration & dosage , Streptococcus pneumoniae , Animals , Cytokines/immunology , Cytokines/metabolism , Lactobacillus/classification , Lung/immunology , Lung/microbiology , MAP Kinase Signaling System , Male , Mice , Mice, Inbred BALB C , Pneumonia, Pneumococcal/microbiology , Specific Pathogen-Free Organisms , Toll-Like Receptors/immunology
4.
Am J Physiol Lung Cell Mol Physiol ; 298(3): L297-303, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19915157

ABSTRACT

Acute pulmonary embolism (PE) is a life-threatening disease, and several vasoconstrictors, including endothelin-1 (ET-1), play a key role in vasoconstriction and hypoxemia during the development of PE. Rho kinase is activated by various vasoconstrictors resulting in vascular contraction and remodeling. Recent evidence has revealed an important role of Rho kinase in the pathogenesis of systemic and pulmonary vascular diseases. However, contribution of Rho kinase in PE remains unclear. We thus investigated the role of Rho kinase in the PE rat model induced by intrajugular administration of polystyrene microspheres (mean diameter, 26 microm). At 6 h following the administration of microspheres (1.5 ml/kg), right ventricular systolic pressure (RVSP) was higher in the PE than in the control rats (15.8 +/- 1.6 vs. 32.9 +/- 7.5 mmHg). Arterial oxygen tension was lower (92.3 +/- 12.5 vs. 66.0 +/- 17.7 Torr), and alveolar-arterial difference in oxygen partial pressure was higher (3.9 +/- 3.8 vs. 36.5 +/- 26.9 Torr) in the PE rats. Western blotting analysis revealed upregulation and downregulation in expression of vascular cell adhesion molecule-1 and endothelial nitric oxide synthase in lungs from the PE rats, respectively, and radioimmunoassay demonstrated an increase in plasma ET-1 levels. Lung Rho kinase alpha expression was greater in the PE rats. At 5 h following administration of microspheres (0.75 ml/kg), intravenous Rho kinase inhibitors HA1077 and Y27632 (3 mg/kg each) attenuated elevation of RVSP (22.0 +/- 3.7, 17.1 +/- 3.2, 14.3 +/- 2.6 mmHg, PE, PE+HA1077, PE+Y27632) and the severity of hypoxemia (66.3 +/- 16.2, 94.9 +/- 23.0, 89.1 +/- 8.5 Torr, PE, PE+HA1077, PE+Y27632) in the PE rats. These results suggest that pulmonary endothelial dysfunction and activation of Rho kinase may contribute to the potentiation of vasoconstriction and hypoxemia in the PE rats.


Subject(s)
Microspheres , Pulmonary Embolism/enzymology , Pulmonary Embolism/etiology , rho-Associated Kinases/metabolism , Acute Disease , Animals , Blood Gas Analysis , Blood Pressure/drug effects , Endothelin-1/blood , Hemodynamics/drug effects , Injections, Intravenous , Lung/drug effects , Lung/enzymology , Lung/pathology , Male , Nitric Oxide Synthase Type III/metabolism , Polystyrenes , Protein Kinase Inhibitors/pharmacology , Pulmonary Artery/drug effects , Pulmonary Artery/pathology , Pulmonary Embolism/blood , Pulmonary Embolism/chemically induced , Rats , Rats, Sprague-Dawley , Vascular Cell Adhesion Molecule-1/metabolism , rho-Associated Kinases/antagonists & inhibitors
5.
Chirurgia (Bucur) ; 101(6): 583-92, 2006.
Article in Romanian | MEDLINE | ID: mdl-17283833

ABSTRACT

Retroperitoneal pyogenic collections can appear in most distinct pathological situations. Establishing the topography and pathogenic route are essential steps in developing the therapeutic attitude. Diagnosis of suppurative retroperitoneal process complicating a previously attested disease is less difficult. The challenges appears in that cases with atypical, clinical picture, which presents associated pathological states (diabetes mellitus, chronic alcoholism, behavioral disturbances), as well as in primary retroperitoneal infections (psoas abscess, infected retroperitoneal tumors) or in that situations in which the patient presents toxico-septic shock on admission. A retrospective study on the patients with retroperitoneal infections admitted in our Clinic between 1996 - 2006 was carried out. We selected the cases in which preoperative etiopathogenic diagnosis was uncertain (in some situations the exact etiopathogenic route remaining unknown even postoperatively). The aim of this study is to evaluate the factors contributing to this, and how therapeutic attitude was influenced.


Subject(s)
Abdominal Abscess/microbiology , Bacterial Infections/complications , Psoas Abscess/microbiology , Abdominal Abscess/diagnosis , Abdominal Abscess/therapy , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/diagnosis , Bacterial Infections/therapy , Diagnosis, Differential , Drainage , Fatal Outcome , Humans , Male , Middle Aged , Psoas Abscess/diagnosis , Psoas Abscess/therapy , Retroperitoneal Space/diagnostic imaging , Retrospective Studies , Risk Factors , Tomography, X-Ray Computed , Treatment Outcome
6.
J Nucl Cardiol ; 8(5): 568-74, 2001.
Article in English | MEDLINE | ID: mdl-11593221

ABSTRACT

BACKGROUND: Technetium-labeled myocardial perfusion tracers allow the simultaneous assessment of myocardial perfusion and left ventricular function by electrocardiography (ECG)-gated myocardial perfusion single photon emission computed tomography (SPECT). This study evaluates left ventricular systolic and diastolic function by ECG-gated SPECT with the use of higher framing (32 frames per cardiac cycle) data acquisition. METHODS AND RESULTS: After receiving an injection of technetium 99m tetrofosmin, 48 patients with cardiac diseases were examined by ECG-gated myocardial perfusion SPECT with a 3-headed gamma camera. During gated data collection, 32 frames per cardiac cycle were acquired over 360 degrees in 60 steps, each of which consisted of 60 beats. Immediately thereafter, the 32 frames taken at each projection angle were combined into 16-frame and 8-frame data sets. Left ventricular end-diastolic volume (LVEDV, in milliliters), left ventricular end-systolic volume (LVESV, in milliliters), and left ventricular ejection fraction (LVEF, percentage) were automatically calculated from the 32-frame, 16-frame, and 8-frame gated data sets. Left ventricular time-volume curves from the 3 data sets were generated by Fourier curve fitting analysis with the use of 3 harmonics, and then peak filling rate (PFR, per second) was measured. Twenty-nine patients also underwent multigated equilibrium radionuclide angiography (ERNA) to determine the LVEF and PFR. Combining the 32-frame data into 16-frame and 8-frame data sets from the 48 patients generated a smaller LVEDV and a larger LVESV, and LVEF was significantly lower in accordance with the decreasing number of frames. Compared with ERNA studies (n = 29), the Bland-Altman method showed underestimated LVEFs and larger 95% limits of agreement in lower framing gated SPECT. CONCLUSIONS: Left ventricular functional parameters obtained from 32-frame gated SPECT correlated closely with those determined by ERNA studies. ECG-gated SPECT with 32-frame data can provide comprehensive information with which to evaluate many types of cardiac diseases.


Subject(s)
Coronary Circulation , Diastole , Gated Blood-Pool Imaging , Heart/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Ventricular Function, Left , Adult , Aged , Female , Humans , Male , Middle Aged
7.
Kaku Igaku ; 38(3): 249-54, 2001 May.
Article in Japanese | MEDLINE | ID: mdl-11452492

ABSTRACT

Multigated equilibrium radionuclide ventriculography from best septal position (LAO view) was performed in 17 patients with cardiac disease with a single detector Anger-type gamma camera (GCA 602A, Toshiba), then immediately imaged with a solid-state, multi-crystal gamma camera (Digirad 2020tc Imager). Acquisition times were the same of 10 minutes. The solid-state gamma camera uses CsI(Tl) as the scintillation material and a Si photodiode. CsI(Tl) has a higher density and higher atomic number than NaI(Tl), so that its efficiency for detecting gamma rays is higher. To confirm this, total acquisition counts in 17 patients obtained from the 2020tc Imager were significantly higher than those obtained from the Anger-type camera (7847 +/- 2061 K vs. 4427 +/- 1162 K counts, p < 0.0001). In comparing left ventricular ejection fractions obtained from the Anger-type camera and the 2020tc Imager data, an excellent correlation was revealed with a correlation coefficient of 0.97 (p < 0.0001). Again, peak ejection rate and peak filling rate obtained from the 2020tc Imager data correlated well with those obtained from the Anger-type camera data (r = 0.93, p < 0.0001 and r = 0.80, p < 0.001, respectively). These data reveal that the 2020tc Imager has an excellent data collection efficiency and a high reliability in assessment of left ventricular function. Thus, the solid-state gamma camera was thought to be a useful hardware in nuclear cardiology.


Subject(s)
Gated Blood-Pool Imaging , Technetium Tc 99m Aggregated Albumin , Technetium Tc 99m Pentetate , Ventricular Function, Left , Aged , Angina Pectoris/diagnostic imaging , Cardiomyopathies/diagnostic imaging , Female , Gamma Cameras , Heart Valve Diseases/diagnostic imaging , Humans , Male , Middle Aged , Myocardial Infarction/diagnostic imaging
8.
J Nucl Cardiol ; 8(2): 152-7, 2001.
Article in English | MEDLINE | ID: mdl-11295692

ABSTRACT

BACKGROUND: Technetium-labeled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function by electrocardiography (ECG)-gated myocardial single photon emission computed tomography (SPECT). The purpose of this study was to evaluate left ventricular performance during dobutamine stress by means of ECG-gated myocardial perfusion SPECT with short-time data collection. METHODS AND RESULTS: After administration of Tc-99m sestamibi or tetrofosmin (600-740 MBq), 67 patients with ischemic heart disease, including 35 with prior myocardial infarction, were examined by ECG-gated myocardial perfusion SPECT at rest and during dobutamine stress (at dosages of 4, 8, 12, 16, and 20 microg/kg/min, with increments every 8 minutes). The ECG-gated data collection time was 5 minutes for each dobutamine dosage. After acquisition of gated SPECT data at the highest dose, thallium 201 chloride (111 MBq) was injected, and dual-isotope SPECT was also performed to assess the myocardial ischemia. In 32 patients without prior myocardial infarction, the sensitivity of individual stenosed-vessel detection with dual-isotope perfusion SPECT, with wall motion abnormality obtained from gated SPECT, and with the combined method was 55.9%, 52.9%, and 73.5%, respectively, based on coronary angiography. ECG-gated SPECT during dobutamine infusion revealed regional wall motion abnormalities (worsening or biphasic response) in 19 (57.6%) of 33 infarcted areas with culprit coronary arterial stenosis. The prevalence of reversible perfusion defects on dual-isotope SPECT was higher in segments with wall motion abnormalities than in segments with normal wall motion response (89.5% vs 42.9%, P <.02). CONCLUSIONS: Myocardial perfusion and left ventricular function during dobutamine infusion were analyzed in a single examination by means of the combined method. This procedure has the potential to provide comprehensive information with which to evaluate patients with ischemic heart disease.


Subject(s)
Coronary Circulation , Dobutamine , Electrocardiography , Heart/diagnostic imaging , Myocardial Ischemia/diagnostic imaging , Organophosphorus Compounds , Organotechnetium Compounds , Radiopharmaceuticals , Technetium Tc 99m Sestamibi , Tomography, Emission-Computed, Single-Photon , Ventricular Function, Left , Blood Pressure/drug effects , Female , Heart Rate/drug effects , Humans , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/physiopathology , Myocardial Ischemia/physiopathology , Sensitivity and Specificity
9.
Asian J Androl ; 3(1): 49-53, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11250794

ABSTRACT

AIM: To examine the transfection of exogenous genes into chick embryos, applying the characteristics of avian leukosis virus (ALV)-induced chicken B cell line DT40 to the production of chimeric birds. METHODS: The DT40 cells incorporated with exogenous gene ( lacZ constructs encoding Escherichia coli beta-galactosidase: beta-gal) were introduced into chick embryos by the injection of cells into stage X blastoderm. Manipulated eggs were incubated for 3 (trial 1) or 6 (trial 2) days, and the expression of lacZ DNA was detected by a histochemical staining method of beta-galactosidase and polymerase chain reaction (PCR) analysis. RESULTS: The survival rates of the manipulated embryos incubated for 3 days (stage 18-20: trial 1) and 6 days (stage 28, 30: trial 2) were about 42% and 38%, respectively. The expression rates of the lacZ gene in the embryos in the trials 1 and 2 were about 60% and 23%, respectively, for the survived embryos. CONCLUSION: The rate of embryonic viability and expression rate of introduced genes were not so high, but it suggested the possibility of utilizing the DT40 cells as a vector for carrying exogenous genes into chick embryos.


Subject(s)
Chick Embryo/enzymology , DNA/analysis , Transfection , beta-Galactosidase/genetics , Animals , Cell Line , Cells, Cultured , Chimera/genetics , DNA/genetics , Electrophoresis, Agar Gel , Gene Expression , Polymerase Chain Reaction , beta-Galactosidase/metabolism
10.
Kaku Igaku ; 38(6): 715-20, 2001 Nov.
Article in Japanese | MEDLINE | ID: mdl-11806082

ABSTRACT

According to improvement of SPECT system, ECG-gated SPECT with 201TlCl have been applied to the left ventricular volumetry. In this study 24 patients without ischemia demonstrated by stress (99mTc-TF) and rest (201TlCl) dual-isotope ECG-gated myocardial SPECT were enrolled. To evaluate left ventricular volumetry using 201Tl ECG-gated SPECT data, the left ventricular end diastolic volumes (EDV) were compared between Quantitative Gated SPECT (QGS) and Emory Cardiac Toolbox (ECT) as well as between dual-isotopes based on the same ECG-gated data. The EDV values with 99mTc data (EDVTc) using QGS were well correlated with those using ECT (r = 0.96, p < 0.0001). Both QGS and ECT demonstrated well correlation between EDVTc (r = 0.98, p < 0.0001) and the EDV value with 201Tl (EDVTl) (r = 0.93, p < 0.0001). However, QGS processing induced significantly lower EDVTl compared with EDVTc. In contrast, EDVTl were significantly higher than EDVTc in ECT performance. The QGS errors subtracting EDVTl from EDVTc were more evident according to the left ventricular volume increase. On the other hand, ECT error showed no tendency associated with the left ventricular volume. From these results, a careful strategy for selection of tracers and softwares should be necessary to assessment of quantitative values derived from ECG-gated SPECT data because of interaction with softwares, tracers, and subjects.


Subject(s)
Algorithms , Tomography, Emission-Computed, Single-Photon/methods , Ventricular Function, Left , Adult , Aged , Electrocardiography , Female , Gated Blood-Pool Imaging , Humans , Male , Middle Aged , Myocardial Ischemia/diagnostic imaging , Myocardial Ischemia/physiopathology , Organophosphorus Compounds , Organotechnetium Compounds , Radiopharmaceuticals , Software , Thallium , Thallium Radioisotopes
11.
Skeletal Radiol ; 30(12): 714-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11810170

ABSTRACT

A rare case of chondroblastoma arising from the temporal bone that occurred in a 60-year-old woman is reported. The tumor appeared well demarcated and osteolytic on the radiographs. CT scan clearly depicted marginal and central calcification in the tumor. MR imaging demonstrated two components in the tumor: a solid component with predominantly low signal intensities on both T1- and T2-weighted sequences, and a multilocular cystic component with T1- and T2-elongation and fluid-fluid levels on the T2-weighted images. Postcontrast MR imaging revealed marked enhancement in the solid component and the septa of the cystic component.


Subject(s)
Chondroblastoma/pathology , Skull Neoplasms/pathology , Temporal Bone/pathology , Chondroblastoma/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Middle Aged , Radionuclide Imaging , Skull Neoplasms/diagnostic imaging , Temporal Bone/diagnostic imaging , Tomography, X-Ray Computed
12.
Hepatogastroenterology ; 47(33): 720-3, 2000.
Article in English | MEDLINE | ID: mdl-10919018

ABSTRACT

BACKGROUND/AIMS: Long-term results were compared for 3 types of distal splenorenal shunt for the treatment of esophageal varices. METHODOLOGY: Between July 1983 and December 1997, 45 patients with esophageal varices underwent distal splenorenal shunt. Group 1 underwent standard distal splenorenal shunt (n = 11). Group 2 underwent distal splenorenal shunt with splenopancreatic disconnection (n = 11). Group 3 underwent distal splenorenal shunt with splenopancreatic disconnection and gastric transection (n = 23). RESULTS: Additional treatment for recurrent varices was required in group 1, (n = 1, 9.1%), group 2 (n = 2, 18.2%), and group 3 (n = 1, 4.3%). All of the patients with recurrent varices developed a shunt stenosis within the 1st year after distal splenorenal shunt. The prevalence of hyperammonemia in group 1 was 40.0% at 1, 5, and 10 years. In group 2, the prevalence was 14.3% at 1 year, 31.4% at 5 years, and 54.3% at 10 years. In group 3, the prevalence was 0% at 1 year, and 9.1% at 5 and 10 years. The differences between group 3 and groups 1 and 2 were significant (P < 0.01). The cumulative survival rates at 1 year were 90.9%, 63.6%, and 95.7% for groups 1, 2, and 3, respectively. At 10 years, the cumulative survivals rates were 70.7%, 63.6%, and 69.4% for groups 1, 2, and 3, respectively. There were no significant differences in survival between the 3 groups. CONCLUSIONS: Distal splenorenal shunt with splenopancreatic disconnection and gastric transection may reduce the incidence of postoperative hyperammonemia.


Subject(s)
Esophageal and Gastric Varices/surgery , Splenorenal Shunt, Surgical , Adult , Female , Humans , Hyperammonemia/prevention & control , Male , Middle Aged , Portal System/diagnostic imaging , Postoperative Complications/prevention & control , Radiography , Splenorenal Shunt, Surgical/methods , Treatment Outcome
13.
J Nucl Med ; 41(8): 1318-23, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10945521

ABSTRACT

UNLABELLED: This study was designed to elucidate the usefulness of crosstalk correction for dual-isotope simultaneous acquisition (DISA) with 99mTc-tetrofosmin and FDG in estimating myocardial perfusion and viability. METHODS: Eighteen patients with coronary artery disease were studied. First, SPECT was performed with a low-energy high-resolution collimator after a single injection of 99mTc-tetrofosmin (single 99mTc-tetrofosmin). Second, PET and DISA with an ultra-high-energy collimator were performed after glucose loading and an injection of FDG. DISA was designed to operate with simultaneous 3-channel acquisition, and weighted scatter correction of crosstalk from the 18F photopeak to the 99mTc photopeak was performed by modification of an existing dual-window technique. The FDG SPECT images were compared with the images obtained by PET. Both crosstalk-corrected and uncorrected 99mTc-tetrofosmin images were generated and compared with the single 99mTc-tetrofosmin images. RESULTS: Regional percentage uptake of FDG agreed well between DISA and PET. However, regional percentage uptake of 99mTc-tetrofosmin was generally higher on the uncorrected 99mTc-tetrofosmin images than on the single 99mTc-tetrofosmin images, especially in areas of low flow (percentage count of 99mTc-tetrofosmin > or = 50%). The crosstalk correction contributed to improving the agreement between regional percentage uptakes and significantly improved the detectability of myocardial perfusion-metabolism mismatching. CONCLUSION: With 3-channel acquisition and weighted-scatter correction of crosstalk from the 18F photopeak to the 99mTc photopeak, DISA with 99mTc-tetrofosmin and FDG is feasible for assessing regional myocardial perfusion and viability.


Subject(s)
Coronary Disease/diagnostic imaging , Fluorodeoxyglucose F18 , Heart/diagnostic imaging , Myocardial Infarction/diagnostic imaging , Myocardium/metabolism , Organophosphorus Compounds , Organotechnetium Compounds , Radiopharmaceuticals , Tomography, Emission-Computed, Single-Photon , Aged , Female , Fluorodeoxyglucose F18/pharmacokinetics , Gamma Cameras , Humans , Male , Middle Aged , Organophosphorus Compounds/pharmacokinetics , Organotechnetium Compounds/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Regression Analysis , Tomography, Emission-Computed, Single-Photon/instrumentation , Tomography, Emission-Computed, Single-Photon/methods
14.
Eur J Nucl Med ; 27(5): 517-23, 2000 May.
Article in English | MEDLINE | ID: mdl-10853806

ABSTRACT

Serial improvement in myocardial perfusion images from the acute or subacute to the chronic stage of acute myocardial infarction (AMI) has been attributed to improved coronary microcirculation or cell function after acute ischaemia and reperfusion. However, conventionally used non-gated imaging cannot eliminate the effect of improved regional contraction. We studied the possibility that such scintigraphic improvement reflects the functional recovery by using ECG-gated myocardial perfusion imaging with technetium-99m sestamibi. Nineteen AMI patients who received acute reperfusion therapy underwent ECG-gated myocardial single-photon emission tomography (SPET) in the subacute and chronic stages. Serial changes in regional image count distributions were analysed on the non-gated, end-diastolic (ED) and end-systolic (ES) images by using segmental mean percent peak activity (MPA) and AMPA (MPA in chronic stage - MPA in subacute stage) on bull's-eye polar maps. These changes were compared with those in regional wall motion on biplane left ventriculography (LVG) from the acute (just after reperfusion) to the chronic stage. During the follow-up, regional wall motion remained the same in 42 (group A) but improved in 17 (group B) of the 59 ischaemically compromised segments. MPA showed no improvement in group A but significant improvement in group B on the non-gated and ES images (P<0.0001 and P<0.001, respectively). However, MPA on the ED images showed no improvement in either group. In the follow-up study of AMI, the scintigraphic improvement documented on the non-gated myocardial images appears to be mainly related to the recovery of wall thickening and not to a real improvement in myocardial perfusion. Therefore, ECG-gated myocardial imaging, which enables simultaneous assessment of changes in perfusion and contraction, is preferable to conventional non-gated imaging for follow-up of AMI.


Subject(s)
Electrocardiography , Myocardial Infarction/diagnostic imaging , Myocardial Reperfusion , Tomography, Emission-Computed, Single-Photon/methods , Acute Disease , Cardiac Catheterization , Humans , Image Processing, Computer-Assisted , Radiopharmaceuticals , Technetium Tc 99m Sestamibi , Ventricular Function, Left/physiology
15.
J Nucl Med ; 41(5): 919-25, 2000 May.
Article in English | MEDLINE | ID: mdl-10809209

ABSTRACT

UNLABELLED: The diagnostic accuracy of cardiac FDG imaging obtained with the dual-head coincidence gamma camera (DHC) is impaired by artifacts induced by nonuniform attenuation. This study proposed a new method (registration and segmentation method for attenuation correction [AC-RS]) to correct these attenuations in the chest region without the need for additional hardware or expensive transmission scanning equipment. METHODS: Before DHC imaging, 99mTc-tetrofosmin SPECT was performed using dual-energy acquisition from both the photopeak and Compton scatter windows. The scatter window images of the 99mTc-tetrofosmin were then registered 3-dimensionally with the cardiac DHC images and segmented into anatomic regions to obtain body and lung contours by applying the optimal threshold method on localized histograms. Theoretic attenuation coefficient values were assigned to the corresponding anatomic regions, and the DHC emission images were reconstructed using these attenuation correction factors. The results were quantitatively evaluated by imaging a cardiac phantom filled with a uniform solution and placed in a chest phantom. Eight nondiabetic subjects were also examined using this technique, and the results were compared with those of measured attenuation-corrected PET images. RESULTS: Use of this technique in phantom and clinical studies decreased the degree of artifacts seen in the inferior wall activity and corrected the emission images. When the results were compared with those of PET scans, the regional relative counts of the uncorrected DHC scan did not correlate with the results of the PET scan. However, the regional relative counts of the AC-RS-corrected DHC scan exhibited a linear correlation with the results of the PET scan (r = 0.73; P < 0.001). CONCLUSION: Reasonably accurate attenuation-corrected cardiac DHC images can be obtained using AC-RS without the need for transmission scanning.


Subject(s)
Coronary Circulation , Gamma Cameras , Heart/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Aged , Artifacts , Female , Fluorodeoxyglucose F18 , Humans , Male , Middle Aged , Organophosphorus Compounds , Organotechnetium Compounds , Phantoms, Imaging , Radiopharmaceuticals , Tomography, Emission-Computed
17.
Ann Nucl Med ; 14(6): 421-6, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11210094

ABSTRACT

To evaluate the effect of left ventricular (LV) size on the calculation of LV function from gated myocardial SPECT with Emory and Cedars-Sinai programs, we performed 99mTc-tetrofosmin gated SPECT on 49 patients with ischemic heart disease. End-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) were semi-automatically calculated by each program. All patients underwent left ventriculography (LVG) within 3 months before and after the SPECT study. We grouped the patients into 22 with a calculated ESV obtained from LVG of over 50 ml (group A) and 27 with an ESV value of 50 ml or below (group B). We then compared the ESV values from gated SPECT with those from LVG in each group. In group A, the ESV from both Emory and Cedars-Sinai programs similarly correlated well with those from LVG (r = 0.92 and r = 0.93, respectively), but in group B, the ESV calculated from the Cedars-Sinai program correlated less with those from LVG (r = 0.53) than those from the Emory program did (r = 0.70). The calculated LV volumes had more errors in the Cedars-Sinai program than in the Emory program, when a patient had a small heart.


Subject(s)
Myocardial Ischemia/physiopathology , Organophosphorus Compounds/pharmacokinetics , Organotechnetium Compounds/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Tomography, Emission-Computed, Single-Photon/methods , Ventricular Function, Left , Adult , Aged , Angina Pectoris/diagnostic imaging , Angina Pectoris/physiopathology , Automation , Diastole , Female , Gated Blood-Pool Imaging , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Myocardial Ischemia/diagnostic imaging , Regression Analysis , Systole
18.
Ann Nucl Med ; 14(6): 453-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11210098

ABSTRACT

123I-labeled 15-(p-iodophenyl)-3R,S-methyl pentadecanoic acid (BMIPP) is a branched-chain free fatty acid that is used to evaluate various cardiac diseases. The aim of the present study was to investigate the relationship between myocardial perfusion (99mTc-sestamibi) and BMIPP uptake, and to correlate perfusion and metabolic alterations with regional left ventricular dysfunction in patients with myocardial infarction (MI). ECG-gated dual-isotope myocardial SPECT was performed on 130 patients with MI with sestamibi (555 MBq) and BMIPP (148 MBq). The patients were classified into 3 groups according to PTCA therapy and the interval between the onset of infarction and RI injection (OR time). Group A (n = 56) included patients whose OR time was less than one month and who had undergone successful PTCA, Group B (n = 36) had OR times of less than one month and had conservative medical therapy, and Group C (n = 38) had OR times of over one month. The severity scores of the dual-isotope images were calculated from the defect scores in 9 segments. From the ECG-gated SPECT data with sestamibi, the left ventricular ejection fraction (LVEF; %) and regional wall motion were determined automatically using the QGS program LVEF obtained from gated SPECT correlated well with the severity scores for sestamibi and BMIPP (r = -0.68 and -0.76, respectively). The delta severity scores (BMIPP scores - sestamibi scores) of Group A were significantly higher than those of the other two groups (3.6 +/- 3.0 vs. 1.5 +/- 1.7 and 1.0 +/- 1.4, p < 0.001 ). The rate of dysfunctional segments with normal sestamihi distribution was significantly higher in Group A than in Group C (20.7% vs. 6.7%, p < 0.001). ECG-gated dual-isotope SPECT is useful since myocardial perfusion, fatty acid metabolism and left ventricular function can be analyzed during a single examination, so that this procedure has the potential to provide comprehensive information when evaluating patients with ischemic heart disease.


Subject(s)
Fatty Acids/pharmacokinetics , Iodine Radioisotopes/pharmacokinetics , Iodobenzenes/pharmacokinetics , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/physiopathology , Radiopharmaceuticals/pharmacokinetics , Technetium Tc 99m Sestamibi/pharmacokinetics , Ventricular Function, Left/physiology , Adult , Aged , Aged, 80 and over , Electrocardiography , Female , Gated Blood-Pool Imaging , Humans , Male , Middle Aged , Myocardium/metabolism , Tomography, Emission-Computed, Single-Photon
19.
Hepatogastroenterology ; 46(29): 2849-53, 1999.
Article in English | MEDLINE | ID: mdl-10576359

ABSTRACT

BACKGROUND/AIMS: The effectiveness of reducing the recurrence rate of esophageal varices by combining partial splenic embolization (PSE) with endoscopic variceal ligation (EVL) was investigated. METHODOLOGY: Patients with complete eradication of esophageal varices were collected as study cases with the following results: 31 cases with PSE and EVL (PSE+EVL group), 25 cases with EVL alone (EVL group), and 33 cases with EIS alone (EIS group). The cumulative recurrence rates were obtained by observing new varices. RESULTS: The cumulative recurrence rates at 6 months were 21.1% in the PSE+EVL group, 58.1% in the EVL group and 32.5% in the EIS group. Those at 1 year were 37.0%, 70.7% and 50.2%, respectively, and those at 2 years were 58.1%, 80.4% and 73.0%, respectively. For all 3 time periods, recurrence rates of the PSE+EVL group were significantly lower than those of the EVL group (p=0.042). Cumulative rates in the PSE+EVL group tended to be lower than those in the EIS group. Further analysis was made on the comparative recurrence rates of the 3 groups, according to Child's classification. The cumulative recurrence rates in Child A cases did not significantly differ between the 3 groups. Cumulative rates in Child B cases were significantly lower in the PSE+EVL group than in the EVL group (p=0.032), and those in the PSE+EVL group tended to be lower than those in the EIS group. These trends were observed between the PSE+EVL group and the EVL group in Child C cases, while cumulative rates did not show differences between the PSE+EVL group and the EIS group. CONCLUSIONS: It was inferred that PSE-combined EVL therapy is a very effective therapy for achieving long-term complete eradication of esophageal varices.


Subject(s)
Embolization, Therapeutic , Endoscopy , Esophageal and Gastric Varices/surgery , Esophagoscopy , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Ligation , Male , Middle Aged , Recurrence , Splenic Artery
20.
Gastrointest Endosc ; 50(1): 7-12, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10385714

ABSTRACT

BACKGROUND: We devised a new combined method of endoscopic variceal ligation and injection sclerotherapy, namely, endoscopic scleroligation, for the treatment of esophageal varices. The aim of this prospective randomized trial was to compare endoscopic scleroligation with endoscopic variceal ligation alone with regard to efficacy, complications, variceal recurrence, and survival. METHODS: Fifty-one patients with cirrhosis and esophageal varices were randomly assigned to be treated by endoscopic scleroligation (n = 25) or endoscopic variceal ligation (n = 26). In the initial session in the endoscopic scleroligation group, endoscopic injection sclerotherapy was performed with injection of 5% ethanolamine oleate around the lower esophagus to obliterate the feeding veins. This was followed by endoscopic variceal ligation from the injection site to the most orad varix. In subsequent sessions, endoscopic injection sclerotherapy was performed with 1% polidocanol. In the endoscopic variceal ligation group, that procedure was performed in all treatment sessions. RESULTS: Both methods were equally effective in achieving complete eradication of esophageal varices. Among the cases in which complete eradication was achieved, the 1- and 3-year cumulative recurrence rates in the endoscopic scleroligation group (9.5%, 22.1%) were significantly lower than those in the endoscopic variceal ligation group (61.9%, 72.2%) (p < 0.01). The survival rates and incidences of treatment-related complications have been similar among patients treated by both methods. CONCLUSIONS: Endoscopic scleroligation is superior to endoscopic variceal ligation in preventing variceal recurrence.


Subject(s)
Esophageal and Gastric Varices/therapy , Gastrointestinal Hemorrhage/therapy , Sclerotherapy/methods , Aged , Combined Modality Therapy , Endoscopy/methods , Esophageal and Gastric Varices/complications , Esophageal and Gastric Varices/mortality , Esophagoscopy , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/mortality , Humans , Iopamidol/administration & dosage , Ligation/methods , Liver Cirrhosis/complications , Liver Cirrhosis/mortality , Liver Cirrhosis/therapy , Middle Aged , Oleic Acids/administration & dosage , Prospective Studies , Recurrence , Sclerosing Solutions/administration & dosage , Treatment Outcome
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