Gamma-camera imaging

Figure 4. Gamma camera image of a patient with medullary thyroid carcinoma showing selective uptake of Re-186-DMSA in a tumor at the base of the neck (taken 24 h after injection).

Figure 5. Gamma camera image of a prostate cancer patient with widespread bone metastases, showing uptake of Re-188-DMSA in bone metas-tases. Left to right anterior, 3 h posterior, 3 h anterior, 24 h posterior, 24 h. 

Figure 4 A set of gamma camera images of a rabbit intravenously injected with Tc-99m-LEH. Twenty-five percent of blood was exchanged with liposome-encapsulated hemoglobin (LEH) (hypovolemic) and the animal was imaged using a gamma camera at various times after infusion. The images clearly show a prolonged circulation of LEH as evidenced by the continued grayscale intensity in heart.

Figure 5.8. Renal specificity of a radiolabelled LMWP. Gamma-camera imaging after an intravenous injection of a radiolabelled low molecular weight protein (LMWP) in the rat, showing the predominant uptake of the LMWP by the kidneys.

None of the smooth surfaces prepared by the depositing of plasma polymer on the smooth surface of Silastic tubing showed detectable thrombus formation by gamma camera imaging. Therefore, they were evaluated by measurement of relative rates of platelet consumption. Table 35.7 shows the results obtained using the plasma polymers described previously [5]. 

Small pegylated liposomes have been shown to extravasate into tumors with leaky vasculature, and the prolonged circulation half-life has a positive effect on the extravasation. Passive tumor targeting of liposomes was visualized in a study of radio-labeled PEG-liposomes in patients with locally advanced cancers, and whole body gamma camera imaging was used to monitor biodistribution and tumor localization. Of 17 patients treated with In-DTPA (Diethylenetri-aminepentaacetic acid) labeled PEG-liposomes, tumor... 

Radiopharmaceuticals that have been used include (1) Cr-(2) Tc-diethylenetriaminepentaacetic acid (DTPA), and (3) I-iothalamate. Cr-EDTA is preferred to 99mplasma clearance of the marker. To ensure accuracy when measuring GFR using urinary clearance methods it is essential that (1) renal... 

Can be used for gamma camera imaging Radioisotopic (simple measurement)... 

Accurate measurement of the various calibration factors to be applied to both the in vivo data and any gamma camera images taken of inhalers and tubing. These latter calibration factors are different from those for the subject and need to be measured using sources or phantoms with known quantities of the same radioactivity as being inhaled. 

Martonen TB, Yang Y, Dolovich M. Definition of airway composition within gamma camera images. J Thorac Imaging 1994 9(3) 188-197. 

Whole body gamma camera images showing I-ior-CEA-(scFv)2 in nude mice bearing LS174T tumours at 24,48 and 72 h post-injection were recorded. In this study, the 1 diabody with a specific activity of 0.21 GBq/mg was used. 

FIG. 4.5. Whole body gamma camera images showing " G-ior-Cr.AI-sc(Fv)2 in a mouse bearing an LS174T tumour at 24, 48 and 72 h post-injection. 

Figure 7.13 Example of a series of gamma camera images of pellet formulation obtained at 0.5 h [a), 10 h (b) and 24 h (c).

The location of a single unit in the GI tract is determined from the position of the gamma camera image. Since no image of the GI anatomy is obtainable, an external radioactive marker may be positioned at a well-defined anatomical position as a reference point in the determination of the radiolabelled formulation. Another approach for facilitating determination of... 

Figure 2 Gamma camera image of the head, lungs, and stomach of a patient following inhalation of radiolabeled Teflon particles from a pressurized canister. (From Ref. 5.)...

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