Myokard-Perfusionsszintigraphie mit 99mTc-Tetrofosmin: Ein Vergleich mit der koronaren Angiographie

Ziel: Die koronare Angiographie ist immer noch die zuverlässigste Methode für die Erfassung der koronaren Herzkrankheit. In der vorliegenden Studie wurde die Genauigkeit der 99mTc-Tetrofosmin Myokard-SPECT hiermit verglichen. Methode: Zweiundfünfzig Patienten (38 m, 14w) wurden mit der 99mTc-Tetrofosmin Myokard-SPECT nach Belastung und in Ruhe untersucht. Zwei unabhängige Beobachter werteten die Aufnahme des Radiopharmakons aus, mit einer Skala von 0 auf 4. Alle Patienten wurden angiographiert und die Ergebnisse wurden mit denen der Szintigraphie verglichen. Wir nahmen an, daß jede Stenose mit einer Lumeneinschränkung von mehr als 50% hämodynamisch wirksam ist, und daß jede Myokardregion mit einer Radiopharmakon-Aufnahme von weniger als 4 ischämisch ist. Ergebnisse: Es gab einen guten segmentalen Zusammenhang zwischen Tetrofosmin-Szintigramm und Koronarangiographie. Sensitivität 72,2-91,1%, Spezifität 80,088,2%, positive Nachtestwahrscheinlicheit 76,4-88,5% und negative Nachtestwahrscheinlichkeit 83,3-85,7% in Abhängigkeit vom obstruierten Gefäß. Schlußfolgerung: Die 99mTc-Tetrofosmin Myokard-SPECT ist eine zuverlässige Alternative für die Erfassung der KHK.

Impact of dopamine transporter single photon emission computed tomography imaging using I-123 ioflupane on diagnoses of patients with parkinsonian syndromes

To assess the impact of I-123 ioflupane single photon emission computed tomography (SPECT) imaging on classifying patients with striatal dopaminergic deficits. Sixty-one patients with an initial diagnosis of parkinsonism or uncertain tremor disorder were screened and followed-up for one year. All patients were re-examined by two neurologists at our centre and were classified as having neurodegenerative or non-neurodegenerative disorders. Patients underwent I-123 ioflupane SPECT imaging. SPECT studies were blindly evaluated and classified as normal or abnormal (indicative of neurodegenerative disorders). The overall agreement of the SPECT imaging results with the initial classification was 65.6% (kappa=0.229, p=0.074) but was 90.2% (kappa=0.782, p<0.001) with the classification of the neurologists at our centre. I-123 ioflupane SPECT imaging is a valuable method in the evaluation of patients presenting clinically with uncertain parkinsonian syndromes or for whom diagnostic doubt exists.

Tc-99m tetrofosmin myocardial perfusion imaging before and six months after percutaneous transluminal coronary angioplasty

The role of Tc-99m tetrofosmin single-photon emission tomography (SPECT) in the evaluation of myocardial perfusion before and 6 months after successful percutaneous transluminal coronary angioplasty (PTCA) was assessed in 41 consecutive patients (32 men and 9 women). Twenty-five patients had one-vessel disease, 14 had two-vessel disease, and 2 had three-vessel disease. Thirty-six patients had dilation of one vessel and five patients dilation of two stenosed vessels, with a total of 46 dilated vessels. All patients underwent coronary angiography both before PTCA and 6 months after revascularization. Restenosis was angiographically demonstrated in 16 (39%) patients and 16 (34.8%) vessels. Tc-99m tetrofosmin myocardial SPECT was 81.3% sensitive and 88% specific for the detection of restenosis in the group of patients with a positive predictive value of 81.3% and a negative predictive value of 88%. Sensitivity, specificity, positive predictive value, and negative predictive value were 81.3%, 90%, 76.5%, and 89.7%, respectively, for restenosis detection in specific vessels. It was concluded that most patients who underwent successful PTCA (34 of 41, or 82.9%) had significant (P < 0.001) improvement in their scan image 6 months after the angioplasty, and that Tc-99m tetrofosmin myocardial SPECT is an excellent tool to follow these patients because it can detect restenosis accurately and noninvasively.

[Myocardial perfusion scintigraphy using 99mTC-tetrofosmin: a comparison with coronary angiography]

AIM

Coronary angiography is still the most reliable method for the detection of coronary artery disease. In this study we compared to this method the accuracy of 99mTc-Tetrofosmin myocardial SPECT.

METHOD

Fifty two patients (38 male and 14 female) were studied with stress-rest 99mTc-Tetrofosmin myocardial SPECT. Two independent observers evaluated the uptake of the radiotracer using a score from 0 to 4. All patients underwent coronary angiography and the results were compared to SPECT findings. We considered as hemodynamic significant any obstruction greater than 50% and as ischemic any myocardial region with radiotracer uptake less than 4 at stress.

RESULTS

There was good segmental correspondence between tetrofosmin scintigram and angiography. Sensitivity 72.2-91.1%, specificity 80.0-88.2%, ppv 76.4-88.5% and npv 83.3-85.7%, depending on the obstructed vessel.

CONCLUSION

99mTc-Tetrofosmin myocardial SPECT is a reliable alternative for the detection of CAD.

A preliminary study of brain gliomas with H17E2 monoclonal antibody: immunoscintigraphy and pharmacokinetics

Ten patients with relapsing high grade brain gliomas and one patient with low grade glioma were studied with a monoclonal antibody (H17E2) against placental alkaline phosphatase. In addition 2 patients with relapsing high grade glioma were studied with a non specific antibody (4D513/2118). 1 mCi of Iodine-131-labelled H17E2 was administered intracarotidly (i.c.) in two, and intravenously (i.v.) in 9 patients. Immunoscintigrams were taken at 0, 2, 24, 48 and 72 hours. Radioactivity was monitored in blood and urine. Tumour/non-tumour ratios were estimated (max. 2.45). All high grade gliomas receiving specific antibody irrespective of the route of administration, gave a positive immunoscintigraphic pattern, increasing in intensity with time. Disappearance of radioactivity in blood was biexpontential with a long component over 30 hours. Urinary excretion of radioactivity ranged from 3.7-21.7% of administered dose/day. The patient with low grade glioma and the patients receiving non specific monoclonal antibody showed a negative pattern, a fast blood clearance and a high urinary excretion. We conclude that a) Iodine-131 labelled H17E2 proved to be stable in vivo and produced satisfactory tumour localisation and b) i.v. route was as good as i.c.

A Preliminary Study of Brain Gliomas with H17E2 Monoclonal Antibody: Immunoscintigraphy and Pharmacokinetics

Ten patients with relapsing high grade brain gliomas and one patient with low grade glioma were studied with a monoclonal antibody (H17E2) against placental alkaline phosphatase. In addition 2 patients with relapsing high grade glioma were studied with a non specific antibody (4D513/2118). 1 mCi of Iodine-131-labelled H17E2 was administered intracarotidly (i.c.) in two, and intravenously (i.v.) in 9 patients. Immunoscintigrams were taken at 0, 2, 24, 48 and 72 hours. Radioactivity was monitored in blood and urine. Tumour/non-tumour ratios were estimated (max. 2.45). All high grade gliomas receiving specific antibody irrespective of the route of administration, gave a positive immunoscintigraphic pattern, increasing in intensity with time.

Disappearance of radioactivity in blood was biexpontential with a long component over 30 hours. Urinary excretion of radioactivity ranged from 3.7–21.7% of administered dose/day. The patient with low grade glioma and the patients receiving non specific monoclonal antibody showed a negative pattern, a fast blood clearance and a high urinary excretion. We conclude that a) Iodine-131 labelled H17E2 proved to be stable in vivo and produced satisfactory tumour localisation and b) i.v. route was as good as i.c.