technetium-tc-99m-bicisate and Chronic-Disease

The purpose of this study was to examine whether the Tc-99m-ECD SPECT can detect any difference between the brain perfusion in patients with chronic pain and normal controls by means of the Statistical Parametric Mapping (SPM96). The subjects were twelve patients with chronic pain (CP group) and twelve normal controls (NC group). After informed consent was obtained, 720 MBq of Tc-99m-ECD was intravenously injected as a bolus. The SPECT data were acquired once for 20 mins from 5 mins after i.v. injection of Tc-99m-ECD, with a triple-head rotating gamma camera. The SPECT data were transformed into a standard stereotactic space, and group comparisons between CP and NC groups were performed on a voxel-by-voxel basis. The subset of voxels exceeding a threshold of p < 0.001 in omnibus comparisons and remaining significant after correction for multiple comparison (p < 0.05) was displayed as a volume image rendered in three orthogonal projections. There was a significant decrease in perfusion in the bilateral thalami in the CP group, suggesting that perfusion in the thalamus generally decreases in patients with chronic pain. Tc-99m-ECD SPECT with SPM96 may be useful for studies of the mechanisms of chronic pain.

Topics: Adult; Algorithms; Chronic Disease; Cysteine; Female; Humans; Image Enhancement; Male; Organotechnetium Compounds; Pain; Radionuclide Imaging; Radiopharmaceuticals; Thalamus

A multicenter study was performed in seven European centers comparing 99mTc-bicisate with 133Xe as a means of evaluating bicisate as a tracer of CBF distribution in humans. The same type of single photon emission computed tomography (SPECT) instrument (Tomomatic) was used in all centers. A total of 115 cases were collected, and of these 105 were considered technically adequate, comprising 18 normal subjects, 18 senile dementia, eight epilepsy, one brain tumor, eight chronic head trauma, and 52 stroke cases. As expected, bicisate gave better spatial resolution than Xe. Agreement between the results of the two methods was noted in 98 cases, but not in the remaining 7, all belonging to the stroke group. These seven all suffered from a subacute stroke (11-23 days after onset), and the disagreement in all cases consisted of bicisate showing low count rate in the area of the infarct and Xe a normal or elevated flow (luxury perfusion) as sign of spontaneous thrombolysis with reperfusion; in fact, these seven cases comprised all the reperfusion cases in the series. The results validate bicisate as a tracer of CBF in normal humans and in chronic brain diseases. Only in a subgroup of subacute stroke cases does bicisate not follow CBF, as it fails to show reperfusion hyperemia. This suggests the usefulness of bicisate in stroke cases, particularly in the subacute phase, where other SPECT methods often present difficulties due to reflow masking the size and the severity of the lesion.

Topics: Aged; Brain Diseases; Brain Ischemia; Cerebrovascular Circulation; Cerebrovascular Disorders; Chronic Disease; Cysteine; Female; Humans; Hyperemia; Male; Organotechnetium Compounds; Reference Values; Tomography, Emission-Computed, Single-Photon; Xenon Radioisotopes

Technetium-99m ethyl cysteinate dimer (ECD) has high initial cerebral uptake with slow clearance in nonhuman primates suggesting ideal characteristics for single photon emission computer tomography (SPECT) imaging. We evaluated the biodistribution, dosimetry and scintigraphic pattern of [99mTc]ECD in normal subjects and the accuracy of SPECT imaging in patients with chronic cerebral infarction. Sixteen normal subjects were injected with approximately 10 mCi of [99mTc]ECD. Anterior and posterior single-pass whole-body images were obtained at multiple times after injection. Blood clearance of the radiotracer was rapid, falling to 10.0 +/- 6.6% and 4.9 +/- 1.1% of the injected dose at 2 and 60 min, respectively. Brain uptake was 6.4 +/- 2.1% of the injected dose 5 min after injection. The critical organ was the urinary bladder. Technetium-99m ECD SPECT was performed with a rotating gamma camera in ten of the 16 normal subjects and 34 patients with clinical and CT evidence of chronic stroke. Thirty-three of the thirty-four patients had focal [99mTc]ECD abnormalities on SPECT (97.1%) based on visual inspection of the SPECT images. In summary, we obtained high quality SPECT images as a result of the optimal physical and biologic characteristics of the tracer. Technetium-99m ECD SPECT shows promise for the evaluation of patients with stroke.

Topics: Cerebral Infarction; Chronic Disease; Cysteine; Female; Humans; Male; Multicenter Studies as Topic; Organometallic Compounds; Organotechnetium Compounds; Radiation Dosage; Reference Values; Tissue Distribution; Tomography, Emission-Computed

Misery perfusion is defined as marginally sufficient cerebral blood supply relative to cerebral metabolic demand. The aim of the present study was to determine the optimal brain Tc-ethyl cysteinate dimer (ECD) SPECT imaging and analysis to detect misery perfusion on O PET imaging in patients with chronic occlusive disease of unilateral internal carotid or middle cerebral artery (MCA).. For 97 patients, cerebral blood flow, cerebral metabolic rate of oxygen, and oxygen extraction fraction were measured using O PET; Tc-ECD SPECT was performed using dynamic scanning with a scan duration of 10 minutes each for 50 minutes after tracer administration. A region of interest was placed in the bilateral MCA territories and in the bilateral cerebellar hemispheres in all standardized images using a 3-dimensional stereotaxic region-of-interest template and affected-to-contralateral asymmetry ratio in the MCA territory (ARMCA) and contralateral-to-affected asymmetry ratio in the cerebellar hemisphere (ARcbl) were calculated.. The ARMCA or ARcbl on Tc-ECD SPECT with a scan time of 20 to 30 minutes after tracer administration (ARMCA20-30 or ARcbl20-30) was correlated with ARMCA on PET cerebral blood flow (r = 0.654) or ARMCA on PET cerebral metabolic rate of oxygen (r = 0.576), respectively, more strongly than with other scan times. The area under the receiver operating characteristic curve for detecting abnormally elevated ARMCA on PET oxygen extraction fraction was significantly greater for ARcbl20-30/ARMCA20-30 (0.947) than for ARMCA20-30 alone (0.780) (difference between areas, 0.167; P = 0.0001) on Tc-ECD SPECT.. Combination of asymmetries in the cerebellar and cerebral hemispheres on Tc-ECD SPECT in a scan time of 20 to 30 minutes after tracer administration optimally detects misery perfusion in unilateral internal carotid artery or MCA occlusive disease.

Topics: Adult; Aged; Arterial Occlusive Diseases; Brain; Cerebral Arterial Diseases; Cerebrovascular Circulation; Chronic Disease; Cysteine; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oxygen Radioisotopes; Positron-Emission Tomography; Tomography, Emission-Computed, Single-Photon

The purpose of this study was to investigate depression-related regions in pre-dialytic patients with chronic kidney disease (CKD) patients. Participants comprised 33 patients with stage 4 and 5 CKD (age, 55 [42-63]) and 32 healthy volunteers (age, 53.5 [49.5-57]). Depressed mood was assessed in the patients, and both groups underwent Tc-99m-labeled ethylcysteinate dimer (Tc-99m ECD) single photon emission computed tomograpy (SPECT). Statistical parametric mapping identified 18 areas of hypoperfusion in the patients in comparison with the normal controls. The largest clusters were areas including left precentral gyrus, right superior and middle temporal gyrus, both cerebellar posterior lobes, both inferior frontal gyrus, right superior and middle frontal gyrus, right cuneus, right inferior parietal lobule, and right putamen. However, there were no specific hypoperfusion areas in CKD patients with depression compared with CKD patients without depression. Interestingly, several hypoperfusion areas in CKD patients (inferior frontal gyrus [BA46], superior temporal gyrus [BA42], anterior cingulate gyrus [BA24]) were concordant with hypoperfusion areas found in patients with major depression who were free of kidney disease. In conclusion, this study did not demonstrate specific depression-related cerebral hypoperfusion areas. However, the cerebral blood flow pattern in CKD patients was similar to that of patients with major depression in some areas. Although further investigations are needed in the future, we suggest that the causes of the higher prevalence of depression in CKD might be associated with this finding.

Topics: Adult; Brain; Brain Mapping; Chronic Disease; Cysteine; Depression; Female; Humans; Kidney Diseases; Male; Middle Aged; Organotechnetium Compounds; Psychiatric Status Rating Scales; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

The purpose of this study was to verify the feasibility and usefulness of a new SPECT method, called triple injection of (99m)Tc-ethylcysteinate dimer (TIE), in evaluation of the delayed or poor appearance of acetazolamide (ACZ) effects in patients with chronic cerebral ischemic disease.. Three equal-volume splits of (99m)Tc-ethylcysteinate dimer were intravenously administered, and 1,000 mg ACZ were used as a vasodilator. A middle cerebral artery territory in the lateral ventricle was used as a region of interest. The data at rest and at 7.5 and 20 min after ACZ challenge (ACZ 7.5 and ACZ 20, respectively) were obtained by dynamic SPECT, and a time response curve to ACZ was obtained through the relative ratio of regional counts to the data at rest, not through regional cerebral blood flow. Nine cases of complete occlusion of the internal carotid artery (IC) and 6 cases of severe IC stenosis were analyzed.. In 12 healthy volunteers (24 cerebral hemispheres) using a placebo (negative control), the values at rest and at rest 7.5 and rest 20 (corresponding to ACZ 7.5 and ACZ 20, respectively) were 100%, 100.4% +/- 2.8%, and 99.6% +/- 3.6%, respectively, indicating the accuracy of the TIE method. In a positive control using 24 normal cerebral hemispheres, prompt maximal vasoreactivity at ACZ 7.5 (124.5% +/- 8.0%) was confirmed, as was continuous vasoreactivity until ACZ 20 (130.1% +/- 12.8%). The values between ACZ 7.5 and ACZ 20 were not statistically different. Patients with complete IC occlusion exhibited a poor response at ACZ 7.5 despite a normal response at ACZ 20 (delayed response). Furthermore, in patients with severe IC stenosis, restoration of cerebrovascular reactivity after carotid endarterectomy was confirmed not only at ACZ 20 but also at ACZ 7.5.. The TIE method using SPECT may be a potentially useful and sensitive strategy in clinical evaluation of the delayed or poor appearance of ACZ effects in patients with chronic cerebrovascular ischemic disease.

Topics: Acetazolamide; Adult; Aged; Aged, 80 and over; Brain Ischemia; Carotid Artery, Internal; Carotid Stenosis; Cerebrovascular Circulation; Chronic Disease; Cysteine; Endarterectomy, Carotid; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

To evaluate the usefulness of a combination of linearization and scatter-attenuation correction on 99mTc-bicisate (ECD)-single photon emission tomographic (SPECT) images, both cerebral blood flow (CBF)-positron emission tomographic (PET) images and ECD-SPECT images from fifteen patients with chronic cerebral infarction were acquired. We measured radioactivity counts in regions of interest (ROIs) on all sets of both images and obtained a 2D scattered graph between ECD-SPECT and CBF-PET data. To evaluate diagnostic accuracy, the sensitivity, specificity and accuracy of ECD-SPECT images were calculated by means of discriminant analysis. The same analysis was also performed on the ECD-SPECT images corrected by a combination of linearization and scatter-attenuation correction. An overall nonlinear relationship was observed between ECD-SPECT and CBF-PET. The sensitivity, specificity, and accuracy of ECD-SPECT images were 69.6%, 91.4% and 73.0%, and those of ECD images corrected by the combination of linearization and scatter-attenuation correction were 79.5%, 95.7% and 82.0% respectively. The clinically diagnostic accuracy of ECD-SPECT images corrected by the combined method apparently increased. So that the linearization with the scatter-attenuation method is useful for improving the diagnostic accuracy of ECD-SPECT images.

Topics: Aged; Brain; Cerebral Infarction; Cerebrovascular Circulation; Chronic Disease; Cysteine; Discriminant Analysis; Female; Humans; Linear Models; Male; Middle Aged; Organotechnetium Compounds; Oxygen Radioisotopes; Radiopharmaceuticals; Scattering, Radiation; Sensitivity and Specificity; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

We compared the acetazolamide challenge test using 99mTc-ECD SPECT and 123I-IMP SPECT images in patients with chronic occlusive cerebrovascular disease. We also evaluated the usefulness of linearization correction for acetazolamide challenge test of 99mTc-ECD SPECT.. Twenty patients with unilateral chronic occlusive cerebrovascular disease (10 patients had middle cerebral arterial lesion and 10 had internal carotid lesion) were included in the study. Split-dose (a dose fractioning was 1:2), and sequential SPECT technique was used for 99mTc-ECD SPECT studies while only acetazolamide challenge test studies for 123I-IMP SPECT were performed. Permeability surface area product model (PS model) and back-diffusion model (Lassen's correction) were used for linearization correction of acetazolamide challenge with 99mTc-ECD SPECT.. Six of 16 patients with reduced vasodilatory capacity in 123I-IMP SPECT were underestimated by 99mTc-ECD SPECT acetazolamide challenge test. Relative ECD uptake normalized by cerebellar uptake compared with IMP uptake showed a nonlinear relationship, indicating relatively less uptake in high flow range. The underestimations of limited vasodilatory capacity observed in 99mTc-ECD SPECT without linearization correction was modified by linearization algorithm. However, the effect of correction based on PS model was superior than that of Lassen's correction. The corrected 99mTc-ECD uptake ratio, based on PS model, and IMP uptake ratio demonstrated a better linear relationship than that of Lassen's correction.. Technetium-99m ECD SPECT corrected based on the PS model is a better method of linearization for evaluating cerebrovascular reserve using acetazolamide challenge.

Topics: Acetazolamide; Aged; Aged, 80 and over; Amphetamines; Cerebrovascular Circulation; Cerebrovascular Disorders; Chronic Disease; Cysteine; Female; Humans; Iofetamine; Male; Middle Aged; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Vasodilation