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How an abdominal ultrasound is done in dogs and cats

Abdominal ultrasound is the most common scan in a veterinary clinic: vomiting and diarrhea, weight loss, abnormal bloodwork, a routine senior checkup, a pre-anesthetic screen. There are many organs, dogs and cats have different reference values, and the patient does not always lie still. Here is how the exam goes, what to look at in each organ and where the time goes after the animal has already gone home with its owner.

What is examined

The animal comes in fasted: dogs and cats usually go without food for eight to twelve hours, with free access to water. It is better not to walk a dog right before the scan, so the bladder stays full. The abdomen is clipped from the xiphoid to the pubis and laterally to the costal arch, the skin is degreased with alcohol and covered generously with gel. Through the coat, even a wet one, the image is noticeably worse.

The patient lies on its back in a padded trough or on its side, depending on the clinician's habit and the animal's temperament. For cats and small dogs a microconvex or linear probe at 7.5-12 MHz works well, for large dogs a 5 MHz curvilinear probe, and for the bowel wall and adrenals in large breeds it still pays to switch to the linear probe. A nervous cat takes two people: one restrains, the other scans. If the animal will not tolerate the exam, sedation is the clinician's call based on the patient's condition.

A fixed scan order makes it easier not to miss anything: liver and gallbladder, spleen, left kidney and left adrenal, right kidney and right adrenal, urinary bladder, then stomach, duodenum, pancreas, small intestinal loops, colon, lymph nodes, uterus and ovaries or prostate. At the end, every region is checked once more for free fluid.

The main obstacles are familiar to everyone: gas in the stomach and bowel, a full stomach in an animal that was fed after all, a dense coat and a tense abdomen in a frightened cat. In deep-chested dogs the right adrenal and the right pancreatic lobe sometimes can only be seen through a right intercostal window. If an organ was not visualized, it is better to say so in the report than to leave the line empty.

• Liver: size, margins, echogenicity, structure, focal lesions
• Gallbladder: content, wall thickness, common bile duct
• Spleen: size, thickness, structure, masses
• Kidneys: length and width, corticomedullary definition, renal pelvis
• Adrenals: thickness of each, shape and structure
• Urinary bladder: wall when distended, content, urethra and ureters
• Stomach and small intestine: wall thickness, layering, motility
• Pancreas, lymph nodes, free fluid, uterus and ovaries or prostate

How long it takes

The scan itself takes fifteen to twenty minutes in a calm animal, longer with a restless cat or a gassy dog. Then comes the report: some thirty lines across the organs, each with its own millimeters, plus descriptions and the impression. Typing it by hand adds another twelve to fifteen minutes, and the report is often finished after the owner has already left with the pet. With ten abdominal scans per shift, typing takes more than two hours.

The same study by voice

Species, breed, weight, age and sex go into the study record before the scan starts, so there is no need to say them. After that the veterinarian says what is on the screen, organ by organ and with numbers, each value lands in its own row, and the species reference shows up right next to it. Below is the dictation from a real case: a seven-year-old cat, routine checkup before a dental under general anesthesia. Play it in full or click individual lines.

Values go into the rows of their organs, not into a block of text. The veterinarian can follow their own order: start with the bladder while it is full, go back to the liver after the bowel, and every number still lands in the right place. The reference next to each value comes from the protocol package, split for dogs and cats, so a bowel wall that is too thick for a cat is visible right away, not on rereading.

Reference values in the protocol are split by species: gastric wall up to 5 mm in dogs and up to 3 mm in cats, small intestinal wall up to 4 and up to 2.5 mm, adrenal thickness up to 7 and up to 4 mm, common bile duct up to 3 and up to 4 mm. Kidney length in cats is 30-45 mm, in dogs it is assessed relative to body weight and breed. These are reference points, not a diagnosis: the final interpretation always belongs to the veterinarian, together with the clinical picture and lab results.

What the finished document looks like

The same data produces the finished documents right away. The table suits the veterinarian and makes comparison with the previous scan easy, while the narrative version is clearer for the owner and for a colleague taking over the patient's treatment.

Frequent questions

What it changes on a shift

In veterinary practice the report often waits until the clinician is done with the next patient, and by then the owner has gone home. If the report is built during the scan, it can be handed over right away, together with the pet and the recommendations.

The first 15 reports are free. After that the price depends on the pack size: from 0.42 to 0.53 USD per report, whatever the length of the dictation. No subscription.

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