Non-invasive in vivo molecular imaging using radionuclides is based on the Radiotracer Principle of G. von Hevesy and the magic bullet concept by Ehrlich (1990). Both principles require administration of a radioactive tracer (a molecule labelled with a radioactive isotope which when injected into a living object can be traced by external radiation detection devices) and require that the quantit...

In recent years, several radiopharmaceuticals have been developed for imaging regional cerebral blood flow (rCBF) such as 75Se labelled PIPSE and MOSE, ²º¹TI labelled DDC and 99mTc labelled HMPAO. HMPAO with two asymmetric carbon atoms (At the 3 and 9 positions), produces d,1 and meso isomers, only one of which is retained in the brain. Rapid intracellular conversion of 99mTc-d,1-HMPAO to...

in recent years, several radiopharmaceuticals have been developed for imaging regional cerebral blood flow (rcbf) such as 75se labelled pipse and mose, ²º¹ti labelled ddc and 99mtc labelled hmpao. hmpao with two asymmetric carbon atoms (at the 3 and 9 positions), produces d,1 and meso isomers, only one of which is retained in the brain. rapid intracellular conversion of 99mtc-d,1-hmpao to hydro...

A simple technique is described for producing high-quality functional images of regional ventilation during physiological tidal breathing of the inert gas 81mKr. These images are quickly obtained on a gamma-camera without the need of computerized systems for data acquisition and display and are directly comparable with those of perfusion obtained with 99mTc-labelled macroaggregates. The short t...

context inherited and sporadic medullary thyroid cancer (mtc) is an uncommon and medically challenging malignancy. even if the extent of initial surgery is deemed adequate, the recurrence rate remains high, up to 50% in most series. measurement of serum calcitonin is important in the follow-up of patients with mtc, and reliably reflects the existence of the disease. evidence acquisition there i...

myocardial ischemia (mi) resulting in infarction is an important cause of mortality and morbidity worldwide. acute ischaemia rapidly impairs myocardial contractile function. myocardial dysfunction persisting for several hours after transient non-lethal ischaemia, eventually resulting in full functional recovery is termed as myocardial stunning. hibernation is now thought to be the consequence o...

A convenient strategy to radiolabel a hydrazinonicotonic acid (HYNIC)-derived tetrazine with 99mTc was developed, and its utility for creating probes to image bone metabolism and bacterial infection using both active and pretargeting strategies was demonstrated. The 99mTc-labelled HYNIC-tetrazine was synthesized in 75% yield and exhibited high stability in vitro and in vivo. A trans-cyclooctene...

The present investigation was undertaken to study the kinetics of 99mTc-labelled diethylenetriaminepenta-acetate (DTPA) as compared with inulin and 51Cr-labelled ethylenediaminetetra-acetate (EDTA). Twenty patients with various degrees of decreased renal function were studied. The renal clearance, plasma clearance and volume of distribution of all three tracers were measured after a simultaneou...

This paper presents a case of an 80-year-old man with idiopathic thrombocytopenic purpura after splenectomy performed many years ago, which normalized platelet count, presented with severe thrombocytopenia with no response to treatment. A SPECT/CT study was performed using 99mTc-labelled Sn-colloid. The histology confirmed the presence of splenic tissue in those foci. Spleen examination (SPECT/...

The value of positive scans of autologous 99mTc-labelled leucocytes in the detection of intestinal inflammation was assessed in 29 patients with known inflammatory bowel disease and a high probability of intestinal inflammation and 58 with a low probability of intestinal inflammation comprising 37 with intestinal symptoms and 21 with suspected abscess. Autologous leucocytes were labelled with 9...