UNLABELLED Heterogeneous perfusion in left bundle branch block (LBBB) has been demonstrated by (99m)Tc-methoxyisobutylisonitrile (MIBI) SPECT. Locally different contraction is also associated with LBBB. Quantitative analysis of myocardial SPECT is influenced by partial-volume effects depending on systolic wall thickening. Therefore, partial-volume effects may mimic perfusion heterogeneity in LB...

PURPOSE This study was to develop an efficient synthesis of (99m)Tc-O-[3-(1,4,8,11-tetraazabicyclohexadecane)-propyl]-α-methyl tyrosine ((99m)Tc-N4-AMT) and evaluate its potential in cancer imaging. METHODS N4-AMT was synthesized by reacting N4-oxalate and 3-bromopropyl AMT (N-BOC, ethyl ester). In vitro cellular uptake kinetics of (99m)Tc-N4-AMT was assessed in rat mammary tumor cells. Tissu...

UNLABELLED To develop a (99m)Tc renal tracer with a capacity to measure effective renal plasma flow comparable to that of the clinical gold standard (131)I-o-iodohippurate ((131)I-OIH) and superior to that of (99m)TcO-mercaptoacetyltriglycine, which has a clearance only 50%-60% that of (131)I-OIH, we investigated (99m)Tc-tricarbonyl nitrilotriacetic acid (Na(2)[(99m)Tc(CO)(3)(NTA)]). This radio...

PURPOSE To determine if there was any difference in the ability of physicians to predict prognosis with technetium 99m ((99m)Tc) sestamibi or (99m)Tc tetrofosmin in a large consecutive series of patients at high risk for coronary artery disease who underwent coronary angiography. MATERIALS AND METHODS This study included 1,818 consecutive patients who underwent a rest and stress single photon...

OBJECTIVES This study was undertaken to 1) compare the regional myocardial tracer distributions between rest technetium (Tc)-99m tetrofosmin and rest-redistribution thallium (Tl)-201 images in patients with coronary artery disease and left ventricular dysfunction; and 2) assess the comparative values of these agents for predicting functional recovery after revascularization. BACKGROUND Tc-99m...

A simple and efficient method for radiolabeling preformed liposomes was developed using hepatobiliary imaging agent (99m)Tc-diisopropyl iminodiacetic acid ((99m)Tc-DISIDA). Chloroform extraction of (99m)Tc-DISIDA from aqueous solutions results in 80% radioactivity in the organic phase due to its lipophilic properties. However, with the presence of reduced glutathione (gamma-Glu-Cys-Gly), chloro...

The aim of this study is to evaluate whether the technetium-99m sestamibi ((99m)Tc-MIBI) single photon emission computed tomography (SPECT) characteristics of pituitary adenomas might be correlated with cavernous sinus invasion, proliferative potential or the multidrug-resistance (MDR-1) gene product P-glycoprotein (Pgp) expression in pituitary adenomas. Fifteen patients with pituitary adenomas...

OBJECTIVE The present study was aimed at evaluating the viability of replacing (18)F with (99m)Tc in dose calibrator linearity testing. MATERIALS AND METHODS The test was performed with sources of (99m)Tc (62 GBq) and (18)F (12 GBq) whose activities were measured up to values lower than 1 MBq. Ratios and deviations between experimental and theoretical (99m)Tc and (18)F sources activities were...