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Questions Asked at the CC View
Is there any free fluid in the abdominal (peritoneal) cavity?	Yes or no
How much free fluid is at the CC view using the AFAST AFS system?	0, 1/2, 1
What does the urinary bladder look like?a	Unremarkable or abnormal
Is the patient intact reproductively?a	Yes or no
Could I be misinterpreting an artifact or pitfall as pathology?	Know pitfalls and artifacts

^a It is important to know that the AFAST target organ approach for parenchymal abnormalities is binary as “unremarkable” or “abnormal” to capture the case for additional imaging and confirmatory testing. More interpretative skills may be gained through experience, and additional ultrasound study and training.

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

The classic CC view includes imaging the urinary bladder (when present) against the abdominal wall in the far‐field by directing the probe externally placed dorsolateral from the midline and the scanning plane directed toward the tabletop into the most gravity‐dependent pouch formed between the bladder and the gravity‐dependent body wall (Figures 6.23 and 6.24). The most gravity‐dependent region at the CC view is referred to as the “CC pouch” (Lisciandro 2011, 2014a; Boysen and Lisciandro 2013). The CC view is slightly a misnomer because of its target organs; only the urinary bladder is specifically imaged whereas the colon is not (Lisciandro 2014a). However, an air‐filled colon will do the following.

 Obscure imaging of the “CC pouch” by dirty shadowing.

 May get between the urinary bladder and body wall, mimicking urine sediment and calculi by its dirty shadowing (see Figure 6.27 and Chapter 11).

A stool‐filled colon may mimic pathology and thus a digital rectal examination and/or caudal abdominal palpation or both as part of a good physical exam can prove helpful along with additional imaging.

Place the probe dorsolateral to midline and direct toward the tabletop into the most gravity‐dependent region of the CC view called the “CC pouch” where the apical urinary bladder and the abdominal wall in the far‐field meet. If the urinary bladder is not in view, slide the probe toward the pubis with some fanning as needed. The process should be a slide and fan, followed by a slide and fan toward the pubis looking for the urinary bladder.

If the colon is creating dirty shadowing, then sweep the probe closer to midline while directing the ultrasound beam into the “CC pouch.”

When the urinary bladder is located, then fan through it in both directions in longitudinal (sagittal) orientation with the same methodology used for the gallbladder and left kidney previously at the DH and SR views, respectively. It is very important to apply minimal probe pressure over the urinary bladder because it is easily deformed by excessive compression of the probe pushing into the patient's body wall. The sonographer can easily appreciate this “artifact” by seeing the urinary bladder appear as a “dumbbell” or its wall flattened out in the far‐field against the body wall in the “CC pouch” (see Figure 6.26).

After interrogating the urinary bladder, return to your starting point by rocking back to the “CC pouch” for one final look in this most gravity‐dependent region for free intraabdominal fluid.

Serial AFAST provides the opportunity to image and interrogate the urinary bladder, which is expected to fill with urine during fluid resuscitation, and if the urinary bladder is not seen then interventional and therapeutic decisions are made depending on the patient.

Urine production may be estimated using our AFAST CC formula of length (cm) × width (cm) × height (cm) × 0.625 = estimation of urinary bladder volume in milliliters (Lisciandro and Fosgate 2017). With serial measurements over time, urine output may be estimated. Excessive probe pressure will distort the urinary bladder, leading to erroneous measurements.

Figure 6.23. The CC view in a dog. In (A) the direction of the probe is shown externally dorsal to midline and directed toward the tabletop, or the most gravity‐dependent region of the view. In (B) is a similar image with anatomy overlay that correlates to the CT image. The urine‐filled urinary bladder serves as a recognizable landmark for the CC view and for identifying the “CC pouch” where the urinary bladder and body wall in its most gravity‐dependent region are next to one another (curved line) as this is where free fluid would pocket. The thigh is often in view through the far‐field and is screen right in (D–F). Computed tomography courtesy of Dr Daniel Rodriguez, VETTEM, and Dr Jesús Paredes, CVM, Mexico City, Mexico.

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

The striated rounded soft tissue structure through the far‐field is often the patient's opposing thigh (“imaging ham”) and not a mass. The rounded anechoic circular structures in between the urinary bladder and the thigh are often appreciated and represent the femoral artery and vein (Figure 6.25; see also Figures 6.23 and 25.8). The compression technique can determine which is the vein and which the artery in addition to the use of color flow Doppler (see Chapter 25).

Pearl: In blunt trauma dogs, the probability of hemoabdomen to uroabdomen has been documented in separate veterinary studies to be ~98% to ~2–4%, respectively (Boysen et al. 2004; Lisciandro et al. 2009; Simpson et al. 2009; Hoffberg et al. 2016; Grimes et al. 2018). Thus, in most canine blunt trauma cases in which the urinary bladder is not visualized, the serial AFAST examination provides a second opportunity to evaluate for the integrity of an intact urinary bladder with its expected rounded contour (Lisciandro et al. 2009). In its absence, radiography, abdominal fluid sampling and analysis, such as comparative abdominal fluid to serum creatinine, or other more advanced imaging procedures should be considered.

Pearl: In cats with large‐volume effusion that survive blunt trauma, the probability of a uroabdomen is much higher than a hemoabdomen because cats generally don't survive large‐volume bleeds like dogs do.