Biomedical subjects

T Massardo

Publications and source records attributed to T Massardo.

At least 19 recordsLinked to original sources

PubMed2003

An assessment of wall motion, perfusion and glucose metabolism in recent myocardial infarction: a comparison in patients with and without revascularization.

The aim of this study was to compare the extent and severity of wall motion abnormalities, perfusion and glucose metabolism, in recent myocardial infarction in patients with and without revascularization. Forty-nine patients were studied (82% men; mean age 58 years) by using echocardiography, 201Tl single photon emission computed tomography (SPECT) rest and redistribution, and 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) SPECT at a mean of 9.2 days (range, 1-24 days) after myocardial infarction. Twenty-seven of the 49 patients underwent revascularization while the other 22 received medical therapy before echocardiography and studies using radionuclides. A contrast angiogram was obtained for each patient. A follow-up echocardiogram at 3 months was obtained for 44 patients. Images were read blindly, using a 17 segment model, with semi-quantitative analysis. In the whole group, the extent of hypokinesia was 15%+/-14 (mean+/-SD); the extent of mild defects was determined as 5%+/-6 by using 201Tl at rest, 6%+/-9 by using 201Tl redistribution, and 4%+/-6 by using 18F-FDG (P<0.0005, echocardiogram/radionuclides). Echocardiography showed that the extent of akinesia-dyskinesia was 16%+/-18 in revascularized patients and 28%+/-18 in non-revascularized patients (P=0.017). With regard to moderate and severe defects, 201Tl rest showed 19%+/-16 and 28%+/-17, respectively (P=0.047); 201Tl redistribution 17%+/-15 and 26%+/-15, respectively (P=0.043); and 18F-FDG 17%+/-13 and 24%+/-15, respectively (NS). In echocardiography, the extent of hypokinetic segments decreased from 16%+/-15 at baseline to 10%+/-11 at 3 months (P=0.045), in revascularized patients. It is concluded that, in recent myocardial infarction, hypokinesia extent on echocardiogram is greater than mild perfusion or metabolic defect extent, reflecting stunning and so the use of radionuclide techniques appear more accurate for defining the extent of myocardial infarction. Non-revascularized patients showed a significantly greater extent of akinesia-dyskinesia and moderate-severe perfusion defects than did revascularized patients, which can be considered a result of therapy. It is suggested that 201Tl rest perfusion be used for the assessment of myocardial infarction soon after revascularization.

Adult↗

PubMed2001

Is (99m)Tc-sestamibi scintimammography complementary to conventional mammography for detecting breast cancer in patients with palpable masses?

UNLABELLED: The aim of this trial was to evaluate in developing countries from different regions the diagnostic performance of (99m)Tc-sestamibi scintimammography (SM) in palpable breast lesions and to verify the clinical usefulness of a joint evaluation with mammography and SM. METHODS: From 10 countries, a total of 238 patients with palpable breast masses (n = 245) were included in this prospective multicenter trial. Prone SM was performed 10 min and 60-90 min (157 patients) after injection using an isotime acquisition of 10 min. Mammography was assessed by the same dedicated imaging radiologist according to breast imaging reporting and data system (BI-RADS) categories for malignancy and breast density. Masked SM findings and mammography findings were checked for a correlation with histopathology findings for excisional biopsy samples. Diagnostic values for breast cancer detection were calculated per lesion. RESULTS: Histopathology revealed 189 cancerous lesions and 56 benign lesions. The sensitivity and specificity of SM were 0.83 and 0.77, respectively. SM diagnostic values did not depend on the incidence of breast cancer in the country of origin or on the timing of imaging (early vs. delayed scans). On mammography, the technique yielded a sensitivity and specificity of 0.85 and 0.66, with 27 mammograms classified as BI-RADS category 1, 33 as category 2, 5 as category 3, 56 as category 4, and 124 as category 5. Thirty-seven lesions were considered to show increased radiologic density. No significant difference was found in SM diagnostic values among different BI-RADS categories or between the groups with low and high breast density. A sensitivity of 96% was calculated when SM and mammography results were combined, with 75% of all false-negative mammography findings classified as true-positive results by SM. CONCLUSION: SM complements mammography in patients with palpable masses and negative mammography findings.

Adult↗

PubMed2000

[Treatment of hyperthyroidism with radioiodine: effects of administered dose on complications and thyroid function].

BACKGROUND: Radio-iodine is a definite therapy for Graves disease hyperthyroidism. However, the optimal dosage is still debatable. AIM: To assess the effects of different radioiodine doses on thyroid function and complications in patients with hyperthyroidism. MATERIAL AND METHODS: A retrospective analysis of 139 patients with hyperthyroidism, treated with ratio-iodine between 1988 and 1998. Radio iodine dose used was classified as low (< 10 mCi), intermediate (10-14.9 mCi) or high (> or = 15 mCi). RESULTS: Thirty-five patients were treated with low doses, 33 with intermediate doses and 71 with high doses. There were no differences between these patients in age, disease severity, frequency of post treatment euthyroidism or complications. Patients treated with low doses had a higher frequency of persistent hyperthyroidism than patients treated with high doses (25.7 and 4.2% respectively, p < 0.001). Likewise, the frequency of subsequent hypothyroidism was 60% in patients treated with low doses and 84.5% of those with high doses, in whom it also appeared earlier. Associated complications were clinically irrelevant. In seven patients, Graves ophthalmopathy progressed after treatment, but this progression was not associated with the dose used. CONCLUSIONS: Radio iodine in high doses is useful, safe and effective for the treatment of Graves hyperthyroidism.

Adolescent↗

PubMed2000

[SPECT tomography with F 18-fluorodeoxyglucose in a recent myocardial infarction clinical case].

We report a 50-year-old woman with a recent myocardial infarction in whom a myocardial perfusion single photon emission computed tomography (SPECT) with Thallium201 was done simultaneously with a F18-fluorodeoxyglucose (FDG) SPECT to study glucose metabolism. Myocardial infarction was located in the anteroseptal and apical regions and an echocardiography, done at the second day of evolution, showed a septo-apical hypokinesia. On the tenth day, a coronary angiography showed a critical lesion of the anterior descending coronary artery and an angioplasty with stent placement was performed on the next day. On the twelfth day, a resting, redistribution 201Tl SPECT to study viability and a FDG-SPECT with a dual head high-energy collimator camera were done. Images, acquired 45 min after injection, were analyzed visually. In anterior and medial apical sectors, discordance between flux and metabolism, considered a classical mismatch, was observed. Echocardiographic hypokinesia disappeared three month after revascularization.

Female↗

PubMed1999

Simultaneous assessment of function and perfusion during dipyridamole-handgrip Tc-99m sestamibi imaging in chronic coronary artery disease.

The main goal of this work was to know the value of ventricular function in addition to perfusion Tc-99m sestamibi images in the assessment of coronary artery disease (CAD) when using dipyridamole (DIP) associated to isometric exercise. We analyzed 52 patients with suspected CAD; 40 of them had coronary lesions > or = 50% and 12 patients without CAD, conforming study and control groups, respectively. Twenty-eight patients had prior myocardial infarction. A two-day sestamibi protocol was employed with i.v. DIP-handgrip and rest injections, acquiring ECG-gated first pass and planar perfusion images. Sensitivity for perfusion images was 85% and specificity was 91.7%. There was no change between rest and DIP ejection fraction (EF) in controls. CAD patients presented a significant EF decrease with DIP (p: 0.0015). Patients with ischemia in perfusion images had larger EF decrease (p: 0.0001). For the analysis, an EF drop > or = 5% and any wall motion abnormality (WMA) were considered as having an abnormal response to DIP. CAD sensitivity improved significantly to 92.5% when adding EF drop and to 90% when adding WMA parameters, but specificity decreased to 75% with EF drop, and to 58.3% with WMA. In conclusion, first pass parameters from DIP-isometric exercise in addition to perfusion images are not a significant help in the assessment of CAD.

Adult↗

PubMed1999

Optimal imaging time for delayed images in the diagnosis of abnormal parathyroid tissue with Tc-99m sestamibi.

PURPOSE: Double-phase scintigraphy with Tc-99m sestamibi is a good method to detect hyperfunctioning parathyroid glands. This study tried to determine the best time for delayed images: 2 or 4 hours. METHODS: Fifty-six patients were studied, and 35 of them had primary hyperparathyroidism (mean age, 53 +/- 13 years; 54% were women). Cervical ultrasonography was performed on 29 of 56 (52%) patients and surgery in 16 of 56 (29%) patients. The dose was 740 MBq (20 mCi) given intravenously, and the acquisition was performed at 10 minutes, 2 h, and 4 h using anterior views, including the mediastinum. Studies that had positive results were analyzed blindly by two independent observers, who selected the best definition for abnormal activity. RESULTS: Nineteen of 56 (34%) studies were negative and 37 of 56 (66%) were positive, 25 of them with one focus and 12 with two or more parathyroid foci. Analysis revealed 76% agreement between the observers (the rest was classified by consensus). In 70% of the cases, the best delayed image was obtained at 2 hours, in 16% at 4 hours (P < 0.00001), and in 14% both images were similar. In those cases with better images at 4 hours, the 2-hour images also showed the lesions. In two patients, lesions were seen only at 2 hours. These results could be explained by tracer decay, washout of parathyroid activity, or both. CONCLUSIONS: The best protocol should include the early 10-minute image and the 2-hour delayed view. Further controls do not appear necessary. This may be important for patient throughput.

Female↗

PubMed1998

[Predictive value of the ergometric test stress parameters for myocardial ischemia according to SPECT thallium-201 scintigraphy].

BACKGROUND: Exercise EKG is used as the test of choice in the diagnosis of coronary artery disease. Classical parameters are angor and ST depression representing myocardial ischemia. AIM: To correlate exercise EKG parameters with SPECT 201Thallium to know their likelihood ratios for ischemia. PATIENTS AND METHODS: Two hundred seventy four patients (171 men), aged 58 years old as a mean, were studied. Of these, 23% had a prior myocardial infarction. The likelihood ratios for the presence of ischemia of ST depression, failure to increase blood systolic pressure, the presence of angor and its duration during stress testing were calculated according to the results of SPECT 201Thallium. Seventy one patients were also subjected to a coronary angiography. RESULTS: Among men, likelihood ratios for the presence of angor, failure to increase systolic pressure, ST alterations and duration of angor were 6.9, 6.15, 1.77 and 1.27 respectively. Among women, the figures were 5.45, 1.77, 0.58 and 1.4 respectively. The diagnostic accuracy of SPECT 201Thallium, when correlated with the results of coronary angiography, was 85%. CONCLUSIONS: Among men, the best exercise EKG predictors for myocardial ischemia were the failure to increase systolic blood pressure and the presence of angor. Among women the only significant predictor was the presence of angor.

Coronary Angiography↗

PubMed1998

[Analgesic response and secondary effects in patients with osteoblastic metastasis, treated with Samarium 153 ethylenediaminotetramethylenephosphate].

BACKGROUND: Samarium153 EDTMP, a beta and gamma emitter, is used in the palliative therapy of painful bone metastases. AIM: To evaluate the analgesic effects and myelotoxicity of Samarium153 EDTMP in patients with prostate, breast and renal carcinoma. PATIENTS AND METHODS: Twenty patients with bone metastases (11 males), aged 65 years old as a mean, received a 1 to 2 mCi/kg intravenous dose of Samarium153 EDTMP, produced in Chile. Patients were followed thereafter during 4 to 40 weeks. Pain was assessed using a visual analogue scale. RESULTS: Pain decreased from a score of 6.4 prior to treatment, to 2.7 at the fourth week of therapy and the effect lasted a mean of 12.5 weeks. Myelotoxicity was observed in 68% of cases (WHO stage I in 21%, stage II in 37%, stage III in 11% and no patients in stage IV). Platelets were the most affected series and neutrophils the least affected. Cell counts returned to normal between the sixth and eighth week. Seventy nine percent of patients decreased their basal analgesic therapy at the sixth week and 88% did so at the eighth week. Forty one percent of these patients discontinued all analgesics. CONCLUSIONS: Samarium153 EDTMP is effective in the treatment of pain in patients with bone metastases and its myelotoxicity is low to moderate. It should be considered as a therapy for this type of pain, with the precaution of performing periodical bood counts.

Adult↗

PubMed1998

[Cushing with transition from pituitary to adrenal origin. Study with SPECT scintigraphy of the adrenal cortex with norcholesterol-I 131 in a case].

The case of a 49 yr old alcoholic women with clinical and laboratory findings that suggested a Cushing syndrome is presented. The functional tests showed cortisol suppression greater than 50% of the basal value with 8 mg of dexamethasone and no response in the combined dexamethasone/desmopressin test. Pituitary Nuclear Magnetic Resonance (NMR) was negative, Abdominal Computed Axial Tomography suggested hyperplastic adrenal glands; adrenal nodules were not found in the NMR. Pituitary or hipothalamic Cushing with secondary autonomous micronodular adrenal hyperplasia was suspected. Norcholesterol-I131 SPECT scintigraphy under dexamethasone suppression demonstrated a functional adrenal hyperplasia which was hystologically confirmed.

19-Iodocholesterol↗

PubMed1996

Is the addition of ECG gating to technetium-99m sestamibi SPET of value in the assessment of myocardial viability? An evaluation based on two-dimensional echocardiography following revascularization.

The main goal of this study was to evaluate whether the addition of ECG gating to technetium-99m sestamibi single-photon emission tomographic (SPET) perfusion imaging assists the prediction of recovery of regional wall motion abnormalities after revascularization. Thirty-six patients with coronary artery disease were included in the study. All had wall motion abnormalities, and 31 (86%) had a clinical history of myocardial infarction. Coronary artery bypass surgery was performed in 18 patients and angioplasty in the remainder. All underwent ECG-gated and non-gated SPET at rest and after intravenous dipyridamole. Two-dimensional echocardiography was performed at a mean of 27 days before revascularization and at a mean of 69 days following revascularization to assess segmental wall motion changes. Perfusion prior to revascularization was analysed qualitatively and quantitatively on gated and non-gated SPET, and the results compared with those of echocardiography. Bullseye parameters were obtained from a normal database, generated from data in 40 normal volunteers, using dipyridamole ECG-gated and non-gated sestamibi SPET. There was good concordance between gated and non-gated qualitative analysis (79% with kappa=0.65) for normal, viable or necrotic segments. Gated SPET predicted functional recovery in 27 of 35 (77%) segments showing echocardiographic improvement while non-gated SPET did so in 30 of 39 (77%) such segments. Gated SPET predicted no functional recovery in 20 of 45 (44%) segments that did not show improved wall motion after revascularization, while with non-gated SPET the figure was 18 of 51 (35%). The positive predictive values of gated and non-gated SPET with regard to the recovery of wall motion following revascularization were 52% and 48%, while the negative predictive values were 71% and 67%, respectively. 99mTc-sestamibi had a low predictive value for recovery of function if visual assessment was used in the analysis of SPET data. Quantitative bullseye sestamibi parameters (defect extension and severity, reversibility and percentage change in extension), from gated or non-gated studies, appear best to distinguish which segments will display improved motility on the echocardiogram after revascularization. The addition of ECG gating does not significantly increase the predictive value of SPET imaging with regard to recovery of function.

Angioplasty, Balloon, Coronary↗

PubMed1996

[Renovascular hypertension. Radionuclide renography for detection and prediction of clinical response to revascularization].

The most frequently used non invasive tests in the diagnosis of renovascular hypertension are the measurement of peripheral blood renin before and after captopril administration, intravenous pyelogram, renal Doppler examination and radionuclide renography without and with angiotensin converting enzyme inhibitor administration. Measurement of renal vein renin levels and renal angiography are invasive tests commonly used. The latter allows an anatomical diagnosis of renal vein stenosis but does not give information about the functional consequences of such lesion and thus, does not predict the response of blood pressure to revascularization. Radionuclide renography has become the most useful non invasive diagnostic test, with a sensitivity and specificity of 83-94 and 85-97% respectively. It also predicts clinical response to revascularization and is useful for follow up after surgery or angioplasty. It also has good results in patients with renal failure, bilateral stenosis or stenosis in a solitary kidney and in transplanted patients.

Adult↗

PubMed1994

[Evaluation of coronary revascularization: comparison between perfusion with dipyridamole Tc99m sestaMIBI and amrinone-echocardiography as predictors of viability].

We studied left ventricular perfusion and motility in 37 patients with coronary artery disease and disturbances of parietal motility, aged 57 +/- 9 years old, before and after revascularization. Perfusion was assessed with dipyridamole-tc99m MIBI SPECT and motility was assessed with two dimensional echocardiography with amrinone. Myocardial segments were defined as normal, viable or necrotic in both studies. Eighteen subjects were subjected to angioplasty and 19 to coronary bypass surgery. Submitted SPECT and echocardiography were repeated 64 +/- 15 and 69 +/- 23 days after revascularization respectively. The concordance between SPECT and echocardiographic pre-revascularization diagnosis was 60.1% Eighty one percent of segments considered viable with SPECT and 71% thus considered with echocardiography improved after revascularization. Likewise, 50% of segments considered necrotic with SPECT and 68% of segment thus considered with echocardiography did not improve. It is concluded that although there is a good concordance between both methods, they have limitations on the study of myocardial viability and should be considered as second choice.

Adult↗

PubMed1994

[Tomographic myocardial perfusion (SPECT) using 99mTc sestamibi-dipyridamole and 2-d-echocardiography with amrinone pre and post myocardial revascularization in 2 cases].

We report two male patients aged 50 and 55 years old with coronary artery disease who were treated with surgical revascularization and angioplasty respectively. To assess viable and ischemic myocardial territories, they were studied before and after revascularization with radionuclide perfusion SPECT with Tc99m-Sestamibi under Dipyridamole and with 2-D echocardiography at baseline and after the use of amrinone. Improvement in relative perfusion on SPECT and wall motion on 2-D echocardiography indicated tissue recovery.

Amrinone↗

PubMed1993

[Radioisotopic evaluation of alginic acid/antacid effect on the prevention of pathologic gastroesophageal reflux (GER)].

In this study the antireflux effect of Antacid/Alginic Acid compound (Batynid (R)) was prospectively evaluated assessed by radionuclide technique. Patients were divided in 2 groups: mild esophagitis 13 patients and severe esophagitis 13 patients. The radionuclide study was done before and posterior ingestion of the compound evaluating duration, severity and number of the reflux episodes. The results show no significant differences comparing gastroesophageal reflux pre and post Batynid, in both group of patients, considering all parameters studied.

Alginates↗

PubMed1991

Long-term prognostic value of a normal dipyridamole thallium-201 perfusion scan.

In a 4-year period, 84 patients who were referred for a dipyridamole thallium-201 stress test to rule out significant coronary artery disease had normal scans. A dipyridamole study was recommended instead of exercise because of arthritis, severe obesity, peripheral vascular disease, pulmonary disease, other chronic illnesses, or combinations of these problems. All patients had three-view (i.e., anterior, shallow left anterior oblique, and steep left anterior oblique) planar thallium-201 imaging 10 minutes and 3.5 hours after administration of 0.6 mg/kg of intravenous dipyridamole. The patients were followed for 42 +/- 13 (range 1-58) months to document the cardiac event rate. Of the 84 patients with normal results, 14 died during the follow-up period from noncardiac causes. Three other patients died 29-51 months after the test due to an acute myocardial infarction, a probable acute myocardial infarction, and sudden cardiac death, respectively. Of the survivors, 5 suffered an acute myocardial infarction 28-50 months after the dipyridamole thallium scan and 1 had coronary artery bypass grafting due to increasing angina pectoris 58 months after the scan (overall cardiac event rate of 0.4% per year). Of the remaining 61 patients, 39 (64%) were asymptomatic, 20 (33%) had the same symptoms they had at the time of testing without significant deterioration, while 2 patients (3%) had deterioration of their chest pains but no cardiac complication. Thus, in this group of patients, a normal dipyridamole thallium-201 perfusion scan predicted a good cardiovascular outcome for at least 24 months following the test.

Adult↗

PubMed1991

[Immunoscintigraphy in stomach neoplasms with anti-CEA BW 431/26 monoclonal antibodies marked with Tc 99 m].

A 57 year old female had a tubular gastric adenocarcinoma confirmed by endoscopy and radiologic studies. Echotomography of the abdomen revealed multiple adenopathies. Immunoscintigraphy with 99mTc labeled anti-CEA BW 431/26 monoclonal antibody was performed. Images obtained at 6 and 24 h showed a significant uptake at the primary lesion and at periaortic adenopathies both in conventional gamma-camera and single emission photon tomography. This immuno-scintigraphic technique may be helpful in the management of patients with gastric cancer.

Adenocarcinoma↗

PubMed1991

[Myocardial contraction and ventricular function in normal subjects evaluated with isotopic ventriculography and phase analysis].

Normal heart contraction was studied in 20 healthy subjects (14 males and 6 female, mean age 33 years). Rest radioventriculography and phase analysis were used. Ejection fraction was 66 +/- 7% for the LV and 53 +/- 7% for the RV (p < 0.0001). Peak filling rates in the first third of diastole were 1.6 +/- 0.6 EDV/sec for the LV and 0.7 +/- 0.3 EDV/sec for RV (p < 0.0001). Time to peak filling rate normalized for heart rate was 180 +/- 52 ms for the LV and 203 +/- 60 ms for the RV (p = 0.05). Filling fractions were 23 +/- 10% and 9 +/- 3%, respectively (p < 0.0001). Segmental motility was normal in all subjects. Phase analysis revealed faster emptying of the left atrium with phase angles of 171 +/- 13 degrees in the LA and 185 +/- 12 degrees in the RA (p = 0.00007). This difference may be related to faster diastolic events in the left ventricle. Phase angles for the LV and RV were -8.75 +/- 3 and -9.44 +/- 5 degrees, respectively (NS). We conclude that activation occurs earlier in the left atrium, proceeds through the septum and then synchronically over both ventricles.

Adolescent↗

PubMed1990

Left ventricular volume calculation using a count-based ratio method applied to multigated radionuclide angiography.

The purpose of this study was to investigate the accuracy of a new count-proportional method for the measurement of left ventricular volume when applied to gated equilibrium blood-pool imaging. An equation is developed that relates total chamber volume, Vt, to the area of a pixel (M) and the ratio (R) of total counts within the chamber to the counts within the hottest pixel in the chamber such that Vt = 1.38 M3R3/2. The value of M is a constant for the particular scintillation camera-collimator system and R is obtained from observed count rates. All calculated volumes were compared to volumes measured using biplane contrast ventriculography. In 25 patients, the method for ventricular volumes gave an r of 0.95 and an s.e.e. of 23 ml [Volume (nuclear) = 0.94 Volume (cath) + 1.3]. Endsystolic volume was best calculated from end-diastolic volume and ejection fraction. Manual regions of interest were more accurate than automated regions of interest. This method appears to be as accurate as more complex approaches and has the advantage of not requiring attenuation correction or blood sampling.

Angiography↗