Arturo Terzi

Diagnosis of acute myocardial infarction by indium-111 antimyosin antibodies and correlation with the traditional techniques for the evaluation of extent and localization

This clinical study evaluated the accuracy of planar myocardial scintigraphy with antimyosin monoclonal antibodies radiolabeled with indium-111 (AMA-Fab) in the detection and localization of acute myocardial infarction (AMI). Fifty-seven patients admitted for suspected AMI were studied; 17 patients underwent thrombolytic therapy with intravenous streptokinase and 11 had clinical signs of reperfusion; 9 had had a previous myocardial infarction. Fifty of 57 patients were discharged from the coronary care unit with a confirmed diagnosis of AMI. The AMA-Fab study results were positive for AMI in 49 patients (98%) and negative in 1 (2%). Among the 7 patients without AMI, 5 had unstable angina, 1 had Prinzmetals variant angina and 1 had acute pancreatitis. AMA-Fab results were negative in 6 of 7 patients (85%) and positive in 1 (15%). Therefore, the sensitivity and specificity of AMA-Fab scintigraphy were 0.98 and 0.85, respectively. To assess accuracy in defining the extent and location of AMI, AMA-Fab results were compared with those of the electrocardiogram, echocardiogram, technetium-99m pyrophosphate myocardial scintigraphy and coronary angiography and left ventriculography. AMA-Fab scintigraphy showed a good concordance with the traditional techniques in the topographic definition of the infarcted regions. No uptake of AMA-Fab was seen in the regions of previous old infarcts. Ten healthy volunteers also underwent AMA-Fab scintigraphy. No evidence of myocardial tracer uptake was noted in them. No adverse reactions or side effects were noted after injection of AMA-Fab in any patient. It is concluded that planar myocardial scintigraphy with AMA-Fab is a reliable method for AMI detection and location.

Possible role of F18-FDG-PET/CT in the diagnosis of endocarditis: preliminary evidence from a review of the literature

Infective endocarditis (IE) is a particular disease which presents with a variety of clinical, aetiological forms and is lethal if not aggressively treated with antibiotics alone or in combination with surgery. This review tries to analyse the possible role of F18-FDG-PET/CT in the diagnosis of IE based on the state of art in literature.

New tracers for the imaging of the medullary thyroid carcinoma

I-MIBG and 99Tcm(V)-DMSA have been recently proposed as scintigraphic markers of the medullary thyroid carcinoma (MTC). Thirty two patients were examined with 131I- or 123I-MIBG and 26 of these were re-examined with 99Tcm(V)-DMSA (planar and SPECT). From our experience we can draw the following conclusions: (1) the scintigraphic attempt was useless in patients with normal levels of plasma calcitonin (CT): (2) in patients with high plasma CT levels, the sensitivity of the MIBG was better in familiar (3/3 true positive) than in sporadic disease (7/21 true positive; overall sensitivity = 42%); the 99Tcm(V)-DMSA was positive in 16/19 cases, (overall sensitivity = 84%) even in cases which had been false negative with MIBG (6 patients); (3) no false positive results were found; (4) the scan with 99Tcm(V)-DMSA is then suggested as the first imaging approach during the follow up in patients affected by MTC and still having high levels of plasma CT. The MIBG scan should be limited to the patients in whom the possible use of MIBG therapy has to be investigated.

Residual brain viability, evaluated by 99mTc-ECD SPECT, in patients with suspected brain death and with confounding clinical factors

BackgroundIn 1968, the Harvard criteria for brain death diagnosis were introduced in clinical practice. These include no movements or breathing, no reflexes, and flat electroencephalogram in the absence of confounding factors, including hypothermia, drugs, electrolyte, and endocrine disturbances. When confounding factors occur, confirmatory tests documenting the absence of cerebral blood flow, such as cerebral angiogram, transcranial Doppler sonography, computed tomography angiography, and nuclear techniques, are required. AimThe aim of this study was to evaluate the clinical value of single-photon emission computed tomography (SPECT) with technetium-99m (99mTc)-ECD in the diagnosis of brain death in a cohort of patients with confounding factors. Fifty-two patients were studied between 1 January 2000 and 23 September 2008. The criteria for the request for 99mTc-ECD SPECT were sodic thiopental withdrawal after less than 24 h, unreceptivity and unresponsivity of brainstem reflexes, anesthesia in the last 24 h, hypothermia, anamnesis for barbiturate use, electroencephalogram artefacts, toxic state, and pediatric criteria. All patients underwent 99mTc-ECD SPECT using a dual-headed camera fitted with a high-resolution low-energy collimator. Images were reconstructed and processed according to standard procedures and interpreted qualitatively by two experienced observers. ResultsThe presence of spots of residual brain viability was observed in 13 patients: 25% of our patient cohort. The patients with residual viability were younger (aged 30.92±17.28 years) in comparison with those with no viability (41.91±18.77 years, P<0.031). Considering the eligibility for transplantation, there were 12 of 13 patients in the residual viability group and 31 of 39 in the no viability group (P<0.0001). All patients with spots of brain uptake were monitored daily by 99mTc-ECD SPECT, and all of them reached the condition of empty skull after one or multiple studies. The opposition to organ donation was observed in six of 13 patients with spots of viable brain tissue and in three of 39 with no signs of residual viability (P<0.001). ConclusionIn patients with confounding factors in whom brain death diagnosis is equivocal, 99mTc-ECD SPECT is a helpful and safe diagnostic approach, allowing a three-dimensional evaluation of cortical and brainstem viability. It guarantees an unequivocal diagnosis of brain death for patients who are potential candidates for organ donation. The persistence of viable spots of brain tissue was found in 25% of our patients and was more frequent in young patients. This affects the opposition to donation.

The value of attenuation correction by hybrid SPECT/CT imaging on infarct size quantification in male patients with previous inferior myocardial infarct.

BackgroundAttenuation correction (AC) has been shown to improve the accuracy of myocardial perfusion single photon emission computed tomography (SPECT) for the detection and evaluation of patients with coronary artery disease. Attenuation artifacts, because of diaphragmatic attenuation, frequently affect the evaluation of the inferior wall, especially in male patients. PurposeThe aim of this study was to evaluate the value of AC for the assessment of infarct size in coronary artery disease patients after inferior myocardial infarction. Materials and methodsGated-SPECT with Tc-labeled compounds with AC by hybrid SPECT/computed tomography (CT) was performed in 56 male patients with documented previous inferior myocardial infarction. Both corrected and uncorrected SPECT images were processed after motion and scatter correction by ordered-subset expectation maximization iterative reconstruction. When needed, a manual realignment between SPECT and computed tomography (CT) sections was performed. Uncorrected and corrected SPECT images were analyzed for perfusion using a 5-point segmental scoring scale from 0 (normal) to 4 (absent). Summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) of the inferior left ventricle wall (inferoseptal, inferior, infero-apical and infero-lateral segments) were determined and compared with the regional wall motion score as determined by uncorrected gated-SPECT. ResultsThe SSS, SRS, SDS for attenuation-uncorrected and attenuation-corrected studies were 14.02±7.9, 9.51±7, 4.5±3.2 and 9.39±7.1, 5.6±6.1, 3.8±2.8, respectively. Differences were statistically significant (P<0.0001) for SSS and SRS but not for SDS. The regional summed rest score of the inferior wall (SRS of inferior segments) showed a better correlation with the regional summed wall motion score of the same segments: R2=0.50 in comparison to uncorrected SRS, R2=0.46. ConclusionThe combination of diaphragmatic attenuation and inferior myocardial infarction determines an artifactual overestimation of infarct size of inferior infarcts. The AC regional perfusion score (SRS) correlates with the regional wall motion score of the inferior wall. AC does not affect the detection and size of residual ischemia (SDS).

Sentinel node biopsy in breast cancer: the experience of Brescia Civic Hospital.

The accuracy of the sentinel node technique in the evaluation of axillary node involvement in breast cancer was evaluated in 83 consecutive patients with monofocal T1–2 carcinoma, who were clinically N0 and who underwent lymphoscintigraphy with 99mTc-colloid integrated with intraoperative sentinel node detection by a portable probe. Lymphoscintigraphy revealed at least one sentinel node in 75 patients (90.4%), always identified by the probe. In eight patients (9.6%) the sentinel node was detected neither by lymphoscintigraphy nor by the probe. All removed lymph nodes were analyzed by hematoxylin-eosin histology and the sentinel node by immunostaining. In 28/75 patients (37.3%) at least one metastatic axillary lymph node was detected; in 16 of the 28 N+ subjects (57%) only the sentinel node was positive. The false negative rate (sentinel node negative/other axillary lymph nodes positive) was 17.85% (5/28 patients). In 9/23 patients (39%) micrometastases were found in the sentinel node only. In conclusion, specific sentinel node positivity in 57% of cases supports the validity of the sentinel node concept. Moreover, nine patients would have been considered No by standard hematoxylin-eosin histology without sentinel node-aided immunostaining. A 17.8% false negative rate calls for caution in patients with negative sentinel nodes.

A cost-effective sestamibi protocol in the managed health care era

BackgroundIn the managed health care era a need exists to lower the cost of diagnostic tests for coronary artery disease. One possible approach is to eliminate the rest study in the conventional stress-rest perfusion imaging protocol with single photon emission computed tomography.ObjectiveThe aim of the study was to determine the frequency with which single stress single photon emission computed tomography acquisition can be used to diagnose disease in normal patients compared with dual stress-rest protocol.Study groupTwo hundred patients without history of myocardial infarction, coronary revascularization, valvular disease, dilated cardiomyopathy, or left bundle branch block undergoing 1-day (n=86) or 2-day (n=114) stress-rest sestamibi imaging were studied. The stress was exercise in 147 patients and pharmacologic in 53 patients.ResultsOn the basis of the stress study, 112 patients had normal images, and 88 patients had abnormal images. On the basis of the combined stress-rest images, 131 patients had normal images, and 69 patients had abnormal images (agreement 85%, kappa 0.68±0.05). Only 6 (5%) of the 112 patients with normal images based on the stress images were considered to have abnormal images by the combined stress and rest images.ConclusionsIn patients with normal stress images elimination of the rest study rarely alters interpretation. Rest studies are most useful in patients with abnormal or equivocal stress images. Such selective elimination of the rest studies may decrease the cost of nuclear procedures and should be considered in the current managed care health system.

Congenital triple kidney in a patient evaluated by F-18 FDG PET/CT for oncologic reason.

Abstract:We report a case of a 78-year-old man with a left apical lung mass suspected to be an adenocarcinoma previously evaluated by thorax computed tomography, who underwent F-18 FDG PET/CT as a staging study. It revealed the unexpected presence of 3 congenital kidneys, 1 on the left side and 2 on

Therapeutic possibilities of 131I-MIBG in metastatic carcinoid tumors--preliminary report.

The poor results of traditional therapy in advanced carcinoid tumors and the well-proven uptake of 131I-MIBG shown by some of these tumors induced us to attempt a radiometabolic approach. We selected for the treatment 5 patients (3 men and 2 women) who showed progression of disease, a fairly good uptake of 131l-MIBG with severe related symptoms, and a poor response to traditional therapy. A cumulative radioactivity of 5.5-29.6 GBq was given. Acute side effects after 131l-MIBG ad ministration or late radiation-induced damages were not observed. Symptoms increased during the first 2-4 weeks in 2 patients: in one of these relief was achieved with drugs. Results concerning objective remission of the disease were unsatisfactory. In contrast, definite improvement of symptoms was shown in 2 of 5 patients, resulting in a better quality of life.

Assessment of myocardial viability by radionuclide imaging

The differentiation of viable from non viable myocardium is a key issue in the current era of revascularization. Several methods have been used to assess myocardial viability. The radionuclide detection of dysfunctional but viable myocardium depends upon the use of radiotracers whose uptake and trapping are related to presence and amount of living cells. The choice of the diagnostic technique to be applied in clinical practice depends on accuracy of the method and availability of resources. SPECT imaging with TI-201 and Tc-99m-myocardial perfusion tracers are widely available diagnostic tools. Several studies have documented their reliability to detect myocardial segments which may improve in both perfusion and function after revascularization. Positron emission tomography after injection of glucose analogues is a more sophisticated and accurate technology to detect viability, whose utilization is at present limited to few centers due to its high cost. Therefore an accurate selection of patients requiring viability studies is needed in order to identify the most appropriate diagnostic test.