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J Coupal

Publications and source records attributed to J Coupal.

16 recordsLinked to original sources
PubMed2000

Single SPECT measures of cerebral cortical perfusion reflect time-index estimation of dementia severity in Alzheimer's disease.

UNLABELLED: To determine the relationship between cerebral cortical blood flow loss and the temporal development of the dementia in Alzheimer's disease (AD), SPECT was studied in a cross section of AD patients with a broad range of impairment. METHODS: Thirty patients with a diagnosis of probable AD had their mini-mental state examination scores transformed into time-index values to give an estimation of dementia severity relative to the developmental time course. SPECT images were obtained using 99mTc-ethyl cysteinate dimer and a 3-head camera. Cortical surface perfusion was analyzed, including modified Talairach standardization, to obtain cortical elements from the convexity (each representing about 0.25 cm2 at the surface, 6.6-mm cortical depth) referenced to the mean perfusion of the full greater cerebellar hemisphere. These element ratios were analyzed (individually and by averages of estimated Brodmann's areas and brain regions) using linear regression with the time-index value. RESULTS: For individual posterotemporal and inferoparietal Brodmann's areas (21, 22 and 39, 40, respectively) the correlation coefficients between cortical perfusion ratios and dementia severity ranged between -0.67 and -0.78 (P < 0.001). Perfusion ratios from these regions declined 2.5%-4.2% for each estimated year of progression. Prefrontal area perfusion showed less association with severity. Perfusion in primary cortical regions had no significant association with dementia severity. CONCLUSION: Cerebral cortical perfusion loss is temporally related to development of dementia. The spatial pattern of high, significant correlations between cortical perfusion and dementia severity shows a regional distribution that corresponds closely to the distribution of AD pathology described in autopsy studies.

Aged↗
PubMed1999

Axillary lymph node uptake of Tc-99m MIBI resulting from extravasation should not be misinterpreted as metastasis.

Ipsilateral axillary lymph node visualization due to extravasation of Tc-99m MDP intravenous injection has been well documented. A patient with suspected angina underwent Tc-99m MIBI myocardial SPECT who had extravasation of Tc-99m MIBI in the antecubital region resulting in ipsilateral axillary lymph node uptake. This finding should not be misinterpreted as lymphatic nodal metastasis in a patient with breast cancer or lung cancer.

Angina Pectoris↗
PubMed1998

Functional retention of Tc-99m MIBI in mediastinal lymphomas as a predictor of chemotherapeutic response demonstrated by consecutive thoracic SPECT imaging.

Tc-99m MIBI is used as a tumor imaging agent and has been proposed to measure p-glycoprotein function, which plays an important role in tumor multidrug resistance to chemotherapy. It has been reported that lung cancer and breast cancer with a high retention of Tc-99m MIBI have been more responsive to chemotherapy than tumors with low retention. Thus Tc-99m MIBI SPECT could be used as a measure of p glycoprotein function and consequently may serve as a predictor of the tumor's responsiveness to chemotherapeutic agents. Described here are two patients with lymphomas, one with non-Hodgkin's lymphoma and the other with Hodgkin's disease, who underwent Tc-99m MIBI thoracic SPECT before and after chemotherapy. The sequential studies demonstrated a reduction in tumor size and diminished tumor uptake in one patient and disappearance of tumor uptake after a course of chemotherapy in the other patient. The data suggest that elevated Tc-99m MIBI uptake in a tumor as a result of retention by p glycoprotein not only demonstrates mediastinal involvement of lymphomas but also may be used to forecast responsiveness to chemotherapy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

Diminished Tc-99m HMPAO pulmonary uptake in ex-smokers.

Normally, there is no localization of Tc-99m HMPAO in the lungs. Tc-99m uptake in smokers' lungs has been reportedly higher than in nonsmokers. Thus, the lung uptake may be used as a barometer of cigarette smoking. To assess whether there is a decrease in pulmonary uptake of Tc-99m HMPAO after cessation of smoking, the authors investigated the lung uptake of 31 male ex-smokers in comparison to smokers and nonsmokers. Anterior and posterior images were taken 10 minutes after intravenous injection of 20-25 mCi of Tc-99m HMPAO. Regions-of-interest over the liver and lungs in the anterior view were calculated. Duration of abstinence from smoking ranged from 5 months to 50 years. The mean lung/liver uptake in ex-smokers was 0.489 +/- 0.019 (sem). In a previous report, the mean lung/liver ratio for smokers (N = 30) was 0.805 +/- 0.040 (sem) and 0.408 +/- 0.019 (sem) for nonsmokers (N = 25). Compared with smokers, the lung/liver uptake ratio of ex-smokers was significantly lower (P < 7 x 10(-9)). The lung/liver uptake ratio of ex-smokers was significantly higher than that of nonsmokers (P < 0.005). The authors conclude that pulmonary Tc-99m HMPAO uptake of smokers is significantly diminished after quitting smoking. However, the lung uptake of ex-smokers is higher than that of non-smokers. The uptake in the lung induced by smoking appears to be partially reversible after the cessation of smoking.

Aged↗
PubMed1994

Diffuse and intense Tc-99m HMDP localization in the liver due to hypoxia secondary to respiratory failure.

After left lower lobe lobectomy for lung carcinoma, a patient had acute respiratory failure secondary to pneumonia and pulmonary embolism requiring a ventilator. Tc-99m HMDP bone scan showed diffuse, intense hepatic uptake. Concurrent liver enzymes indicated hepatic necrosis. Two weeks later the patient died and a limited chest autopsy confirmed acute adult onset respiratory distress syndrome. Etiologic factors of massive hepatic necrosis in relation to hepatic localization of bone imaging agent and its prognostic outcome are discussed.

Aged↗
PubMed1991

Tc-99m HMPAO diffuse pulmonary uptake demonstrated in cigarette smokers.

Tc-99m HMPAO, a lipophilic radiotracer used as a brain SPECT imaging agent in the diagnosis of strokes and dementias, is normally localized in the brain and the heart and is excreted through the kidneys (50%) and the hepatobiliary system (14% to 30%). There is no pulmonary localization except in the lungs of smokers. To evaluate pulmonary localization of Tc-99m HMPAO in relation to smoking, 23 patients (aged 27 to 76 years) who were referred for brain imaging studies for strokes or dementias also underwent lung imaging studies immediately following the brain imaging. Anterior and/or posterior lung images were obtained 30 to 45 minutes after IV injection of 15 mCi Tc-99m HMPAO. Diffuse pulmonary uptake was graded semiquantitatively: 3+, pulmonary uptake is equal to or higher than hepatic uptake; 2+, pulmonary uptake is less than hepatic uptake but higher than cardiac uptake; 1+, pulmonary uptake is equal to cardiac uptake; 0, pulmonary uptake is less than cardiac uptake. Each patient's smoking history, including duration and daily consumption, was recorded. Four patients' lung images showed 3+ lung uptake; 6 patients, 2+; 1 patient, 1+; and 12 patients, 0 uptake. Eleven patients with lung uptakes of 3+ to 1+ had a history of cigarette smoking. Twelve patients with lung uptake less than cardiac uptake had no smoking history. Pulmonary distribution of Tc-99m HMPAO is usually negligible in the normal lung. Our results indicate that lung uptake correlates significantly (chi-square = 23, d.f. = 1, P = 0.0001) with smoking history.

Adult↗
PubMed1990

Assessing utility of single photon emission computed tomography (SPECT) scan in Alzheimer disease: correlation with cognitive severity.

Diagnosis of probable Alzheimer disease (AD) is made by a combination of characteristic clinical findings, when normal laboratory studies reveal no structural or metabolic cause of the dementia. Definite diagnosis of AD, however, can only be made with brain tissue examination. PET scanning reveals parietotemporal decreases in cerebral blood flow (CBF) and glucose metabolism that differentiate AD from normal elderly and from multi-infarct dementia. Preliminary studies suggest that similar defects in CBF are detectable in single photon emission computed tomography (SPECT) in AD. Utilizing the iodinated ligand [123I] HIPDM ([123I] hydroxyiodobenzylpropanediamine), we studied 19 patients with probable AD of varying severity, with emphasis on mild cases, to assess the utility of SPECT as a diagnostic test in AD. Parietotemporal perfusion on SPECT was decreased unilaterally or bilaterally in 16 of 19 AD patients, similar to the defects reported with PET. The degree and extent of decreased CBF on SPECT correlated with AD severity. Strong correlations were obtained between decreases in computer-generated ratios of parietal to cerebellar activity and the level of cognitive function. SPECT was read as normal (on the radiographic film) by the nuclear medicine physician in all cases with Mini-Mental State (MMS) score greater than 24, and showed bilateral parietal perfusion deficits in only 1 of 4 patients with MMS between 22 and 24. Ten of 12 patients with MMS less than or equal to 21 had bilateral parietal abnormalities; the other 2 had unilateral perfusion defects. All patients with MMS less than 15 were bilaterally abnormal. SPECT is less expensive and more widely available than PET, and may have an adjunctive role in diagnosis of AD and other dementias if utilized under the proper circumstances.

Aged↗
PubMed1988

Detection of pulmonary edema and hemorrhage using indium-111 chloride images: rat model.

Pulmonary edema and/or hemorrhage (PEH) induced by IV injection of norepinephrine was demonstrated in six rats by In-111 chloride lung/heart imaging. The anesthetized rats were positioned under a gamma camera using a pinhole collimator. After In-111 chloride IV injection, analog thorax images were obtained and dynamic data were recorded at 30 seconds/frame for 20 min before and after induced PEH. The gamma camera was interfaced to a computer which generated the curve of the lung/heart radioactivity ratio which rose from 0.4-0.5 at baseline to 1.0-1.4 at the end of the study. The image after IV norepinephrine injection showed a reversal of the lung/heart radioactivity concentration. In-111 chloride instantly binds to plasma transferrin yielding an excellent intravascular imaging agent. Leakage of this tracer into alevoli indicates loss of aveolar membrane wall competence. Pulmonary edema, as in acute respiratory distress syndrome, is difficult to diagnose radiographically and this In-111 chloride lung/heart imaging technique may be potentially useful.

Animals↗
PubMed1986

111In-chloride thorax scintigraphic study for demonstration of pulmonary edema: canine model.

Pulmonary edema induced by injections of oleic acid was demonstrated using 111In-chloride lung/heart image in five anesthetized dogs. The anesthetized dogs were positioned under a gamma camera interfaced to a computer. After 111In-chloride IV injections, dynamic data were recorded at 1 frame/min before and after induced pulmonary edema. The computer generated the curve of the lung-to-heart activity ratio; the ratio rose from 0.5-0.6 at baseline to 0.85-1.5 at the end of the study in the dogs. At the end of each study, the removed lungs demonstrated edematous fluid, and a few red blood cells were seen in the alveoli. The results indicating pulmonary edema exhibited in the 111In-chloride lung-to-heart ratio obtained from a computerized gamma camera were compatible with the pathological result. Since 111In-chloride instantly binds to plasma transferrin, an excellent intravascular imaging agent, leakage of this tracer into alveoli indicates loss of membranous wall competence. Pulmonary edema, as in the adult respiratory distress syndrome, is sometimes difficult to diagnose; and this 111In-chloride lung-to-heart imaging technique may be potentially useful.

Animals↗
PubMed1981

Biologic gastric emptying time using Tc-99m TETA polystyrene resin in various clinical conditions.

In 82 subjects 82 gastric emptying studies using Tc-99m triethylene tetramine polystyrene resin were retrospectively evaluated. All six patients with diabetic gastroenteropathy (GE) had delayed biologic gastric emptying time (BGET) that responded well to metoclopramide (MP) injection. In 11 diabetics without GE, only two had prolonged BGET with good response to MP. All 11 patients with gastric outlet obstruction also had prolonged BGET, but no significant response to MP was found in 7 studies. Five of 7 patients with active gastric ulcer had delayed BGET. Three of ten patients with previous Billroth I or II operation had accelerated BGET, and 3 of 9 patients with previous vagotomy had delayed BGET with good response to MP. Markedly prolonged BGET with significant response to MP was also observed in 3 patients with disordered gastric motility. Delayed BGET was found in one patient with bile reflux gastritis and in 2 of 6 patients with reflux esophagitis. No prolongation of BGET was observed in 6 symptomatic patients whose radiographic and endoscopic examinations were negative. BGET studies with this agent appear to be reliable and very helpful in the management of patients with gastric symptoms and for obtaining an objective measurement of the response to therapy.

Adolescent↗
PubMed1981

Evaluation of biliary disease by scintigraphy.

The value of biliary scintigraphy was studied in 180 patients with suspected biliary tract disease. Scintigraphy was performed after intravenous injection of technetium-99m labelled (1) N-substituted iminodiacetic acid derivative (HIDA) in 91 patients, and (2) butyl derivative of iminodiacetic acid (BIDA) in 89 patients. Most of the patients were investigated additionally by conventional techniques such as cholecystography, cholangiography and ultrasonography. It is concluded that biliary scintigraphy is a simple and safe technique for visualization of the biliary tract. It is particularly useful in the evaluation of acute cholecystitis, in patients with iodine sensitivity requiring imaging of biliary tract, and in the differentiation of obstructive from nonobstructive jaundice. Its value in kinetic disturbances of the gallbladder and in quantitative evaluation of hepatobiliary function needs further study.

Adolescent↗
PubMed1979

Pharmacokinetics of hepatobiliary imaging agents in rats: concise communication.

The distribution and elimination kinetics of Tc-99m pyridoxlidene glutamate (Tc-99m PG), of Tc-99m N-(2,6-dimethyl-phenylcarbamoylmethyl) iminodiacetic acid (Tc-99m HIDA), and of I-131 rose bengal in blood were quantitated after i.v. injection in rats. This was performed by use of a unique indwelling catheter that externalizes the systemic circulation, permitting continuous monitoring of blood radioactivity. The blood activity-time curves of Tc-99m PG and Tc-99m HIDA are described by the sum of three exponential functions. Only two exponentials are required in the case of I-131 rose bengal. The rank order for the rates of loss from blood was Tc-99m HIDA less than Tc-99m PG less than I-131 rose bengal. Bile was collected after administration of Tc-99m HIDA and Tc-99m PG. The total excretion of radioactivity over a 70-min period amounted to 95.7% and 42.8% of the dose of Tc-99m HIDA and Tc-99m PG, respectively. A linear compartmental kinetic model was developed to account for the disappearance from blood and the biliary excretion of these radiopharmaceuticals in rats.

Animals↗