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You will need to know how to freeze the image on the screen. This is especially helpful when you have short‐duration images of the region of interest. Examples include air (lung) interference of cardiac views in a panting patient, the tachycardic patient with normal higher heart rates (cats) in which the eyeball method is error prone; or you caught a quick glimpse of a structure you want to measure. Freezing the image on the screen and then rolling the cine ball through preceding frames allows you to evaluate better than in real time.

Figure 5.17. Slice‐thickness artifact at the AFAST CC view. (A) and (B) are the same images within the same cine loop that have been extracted to show how much gain settings affect the image. In (A) is a slice‐thickness artifact that is circled in (C). In (B) the gain is turned down, eliminating the artifact (true sediment would persist in gravity‐dependent regions). Color flow Doppler is another technique used to look for flow (mass versus thrombus versus sediment versus artifact). (C) and (D) are labeled images of (A) and (B) respectively. Note how the loop of small intestine outside the lumen of the urinary bladder could mimic a bladder stone (cystic calculi) with a hyperechoic line (reflective air) and clean shadowing through the far‐field. Note also that the screen provides a lot of information including a depth of 10 cm, an abdominal preset (Abv) in the upper right. Note, there is uniquely no focus cursor on machines from this manufacturer (SonoSite). Arrows indicate the body wall in the CC pouch. SI, small intestine; UB, urinary bladder.

Source: Courtesy of Dr Gregory Lisciandro, Hill Country Veterinary Specialists and FASTVet.com, Spicewood, TX.