Ultrasonography in the preoperative assessment of candidates for laparoscopic cholecystectomy: examination technique and results]

We have investigated the use of a microwave cavity (Labwell AB, Sweden) to improve the radiochemical yield of 2-18F]fluoro-2-deoxyglucose (2-18F]FDG). After characterizing the heating properties of the cavity, three steps of the Hamacher 2-18F]FDG synthesis which require heating--azeotropic distillation of the target water, nucleophilic substitution, and hydrolysis of the product--were investigated separately. The average radiochemical yield of 2-18F]FDG for the microwave synthesis, using the phase transfer reagent tetrabutylammonium bicarbonate, was 62 +/- 4% (72 +/- 5%, decay corrected, synthesis time = 31 min).