Today's Veterinary Practice

NOV-DEC 2015

Today's Veterinary Practice provides comprehensive information to keep every small animal practitioner up to date on companion animal medicine and surgery as well as practice building and management.

Issue link: http://todaysveterinarypractice.epubxp.com/i/591321

Contents of this Issue

Navigation

Page 26 of 107

tvpjournal.com | November/December 2015 | ToDay's VeTeriNary PracTice small aNimal abDomiNal UlTrasoNograPhy Peer reviewed 25 signifies the direction of the US beam relative to the image. Each machine's marker is different, but convention states that, when the transducer is oriented parallel to the long axis of the dog or cat, the marker should be positioned cranially. 7. Gain Adjustment Use the gain adjustment and TGC or DGC controls to adjust overall image brightness (Figure 3). However, remember that this is a postprocessing technique that increases the overall whiteness of the screen. It has no effect on the production, transmission, or processing of US waves. When using the TGC or DGC settings (Figure 4 ): Use the mid-range as a starting point for setup; then adjust the sliders from a straight vertical FIGURE 3. Three different images from a 0.5 dB US phantom. In A, the overall gain setting is normal (usually around 60%). In B, the overall gain setting is too low resulting in an overall hypoechoic image (gain setting at 50%). In C, the overall gain setting is too high resulting in an overall hyperechoic image (gain setting at 78%). These gain values are specifc to your US; therefore, ensure that the overall gain is adjusted appropriately for your machine. FIGURE 4. Image manipulation using the TGC or DGC curves. In A, the near feld TGC sliders have been moved too far to the right resulting in a "white" near feld. In B, the near feld TGC sliders have been backed off too much, so that the overall echogenicity of the phantom does not appear uniform and is too dark close to the transducer. In C, the sliders specifc to the 1, 3, and 4 cm distance markers have been set to the far left, resulting in no image at all. A B C A B C

Articles in this issue

Links on this page

Archives of this issue

view archives of Today's Veterinary Practice - NOV-DEC 2015