| high-resolution imaging | <technique> High Resolution Electron Microscopy is phase contrast microscopy of the atomic structure of materials. In most crystalline inorganic materials and a number of polymeric materials HREM allows the imaging of individual atomic columns. The images can frequently be interpreted in terms of the projected crystal potential, although it is often necessary to match the experimental images with those calculated from multislice algorithms. Allows direct measurement of lattice parameters, inspection of individual defects and grain orientation. (05 Aug 1998) |
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| secondary electron imaging | <microscopy> Production of secondary electrons is very topography related. Due to their low energy, 5eV, only secondaries that are very near the surface (less than 10nm) can exit the sample and be examined. Any changes in topography in the sample that are larger than this sampling depth will change the yield of secondaries due to collection efficiencies. Collection of these electrons is aided by using a collector in conjunction with the secondary electron detector. The collector is a grid or mesh with a +100V potential applied to it which is placed in front of the detector, attracting the negatively charged secondary electrons to it which then pass through the grid-holes and into the detector to be counted. When a Secondary Electrons collide with the solid-state saemiconductor detector an electron-hole pairs are created which are then counted. This quantity is translated into a pixel intensity and displayed on the CRT, forming the image. (05 Aug 1998) |
| neoplasm: gallium imaging | <radiology> Useful: Hodgkin disease and histiocytic form of NHL poor sensitivity below the diaphragm, Burkitt lymphoma: almost 100% sensitivity, hepatoma: 90% sensitivity, melanoma: 90% sensitivity, leukaemia possibly useful: NHL: good for large and mediastinal lesions, nodal metastases from seminoma and embryonal cell carcinoma: 87% sensitivity, non-small cell lung CA: 85% sensitive not useful: head and neck, GI (especially adenocarcinoma), breast, gynaecological, kiddie tumours see: gallium: indications (12 Dec 1998) |
| nuclear magnetic resonance imaging | A special imaging technique used to image internal stuctures of the body, particularly the soft tissues. An MRI image is often superior to a normal X-ray image. It uses the influence of a large magnet to polarize hydrogen atoms in the tissues and then monitors the summation of the spinning energies within living cells. Images are very clear and are particularly good for soft tissue, brain and spinal cord, joints and abdomen. These scans may be used for detecting some cancers or for following their progress. Acronym: MRI (11 Nov 1997) |
| dark field imaging | <microscopy> Using a single diffracted beam to form the image in a transmission electron microscope. This causes all regions of the specimen not of the same crystal structure and orientation as the region which produced the diffracted beam to be represented as very dark in the final image, allowing phase differentiation visually in the transmission electron microscope. (05 Aug 1998) |
| diagnostic imaging | Any visual display of structural or functional patterns of organs or tissues for diagnostic evaluation. It includes measuring physiologic and metabolic responses to physical and chemical stimuli, as well as ultramicroscopy. (12 Dec 1998) |
| dipyridamole-thallium imaging | <radiology> Myocardial perfusion imaging for patients who cannot exercise, dipyridamole, potent coronary vasodilator, dose: 300 mg IV, side effects relieved by aminophyllin, thallium given when: symptomatic, HR increased 10 bpm, diastolic BP decreased 10 mm Hg, 45 min after PO dose (12 Dec 1998) |
| imaging | Radiological production of a clinical image using X-rays, ultrasound, computed tomography, magnetic resonance, radionuclide scanning, thermography, etc.; especially, cross-sectional imaging, such as ultrasonography, CT, or MRI. Origin: see image (05 Mar 2000) |
| imaging agents | Proteins developed to act as imaging or contrast agents for use with various types of bodyscanners. The proteins, usually antibodies, bind to specific tissue types, usually tumours, and allow the scanner to distinguish those tissues from the surrounding tissue very easily. (14 Nov 1997) |
| imaging department | The diagnostic radiology department. See: imaging, radiology. (05 Mar 2000) |
| inflammation: gallium imaging | <radiology> Pathophysiology: leakage of protein-bound Ga-67 into extracellular space secondary to increased capillary permeability, Ga-67 is preferentially bound to nonviable PMNs and macrophages, leukocyte incorporation (rich in lactoferrin), bacterial uptake (siderophores), inflammtory tissue stimulates lactoferrin production for chronic abdominal inflammation: 67% sensitivity; 64% specificity; 13% false negatives; 5% false positive, dose: 5 mCi; imaging: 24, 48, 72 hours, diffuse uptake in peritonitis, localised uptake in acute pyogenic abscess, phlegmon, acute cholecystitis, acute pancreatitis, acute gastritis, diverticulitis, inflammatory bowel disease, surgical wound, pyelonephritis, perinephric abscess see: gallium indications, gallium vs. Indium (12 Dec 1998) |
| through transfer imaging | The production of an ultrasound image by detection and analysis of sound on the opposite side of the body from the emitting transducer. Synonym: through transfer imaging. (05 Mar 2000) |
| thyroid imaging | <radiology> Tc-99m pertechnetate 6 mCi, I-123 sodium iodide 200 - 400 uCi PO (12 Dec 1998) |
| transfer imaging | The production of an ultrasound image by detection and analysis of sound on the opposite side of the body from the emitting transducer. Synonym: through transfer imaging. (05 Mar 2000) |
| ultrasound imaging | <investigation, procedure> A technique in which high-frequency sound waves are bounced off internal organs and the echo pattern is converted into a 2 dimensional picture of the structures beneath the transducer. (12 May 1997) |