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Generally, the SR view has few artifacts which are mostly colon and stomach related. The anatomy of the SR view is important to know because of the viscus organs located cranially (stomach) and caudally (transverse and descending colon). When these organs are air filled, dirty shadowing is created through the far‐field, limiting imaging to a pie shape of information that includes the left kidney, head of the spleen in dogs and cats, great vessels and variably loops of small intestine (see Figures 6.17–6.19). Artifacts are described in more detail in Chapters 3 and 5.

Figure 6.19. Examples of typical positive studies at the SR view. In (A) the spleen is in the near‐field identified by its characteristic location (importance of performing the SR view the same way every time), its hyperechoic capsule, and vessels splitting its capsule. Classic triangulation between the spleen and the left kidney. In (B) is another positive with a similar location of free fluid with the triangulation outlining the spleen from the stomach (screen left) and left kidney (screen right). With fanning through the region, the left kidney is easily identified to the right of the near‐field of the image. In (C) free fluid is located between the left kidney and spleen. In (D) is shown the classic triangulation off the cranial pole of the left kidney where it abuts the wall of the colon. In (E) there is some perirenal fluid to the left of the kidney that is similar to the image from another case in (F). Note differences in image quality and ultrasound machine settings making it easier or more difficult to see. Serial examinations are key when subtle findings are suspected. Moreover, the SR view is complemented by information from other AFAST views. Compare these images to the anatomy in Figures 6.17 and 6.18. Note the consistency in the images with their proportionality and location of the relevant SR view structures of the left kidney, spleen, stomach and colon.

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

Figure 6.20. Edge shadowing artifact off the left kidney. (A) and (B) are the same image unlabeled and labeled for comparison. In (B) the hypoechoic linear edge shadowing artifact in (A) is outlined with (V) and with a thin black line. When free fluid is suspected off the margin of a curved surface, this artifact should always be considered as creating a false positive. Compare to Figure 6.19 (E) and (F).

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

Figure 6.21. Both kidneys in view at the SR view. In the cat and the small dog, it is not uncommon to see both kidneys through the SR view. LK, left kidney; RK, right kidney.

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