Ultrasound for Dogs and Cats: What It Shows and How to Read It

Reviewed by the LabReadAI medical team
Ultrasound for Dogs and Cats: What It Shows and How to Read It

Ultrasound is one of the main ways to look inside a pet without pain or radiation. The vet sees the structure of organs, and the owner gets a report full of unfamiliar words. Let's break down what an ultrasound shows in dogs and cats, how to prepare the animal and how to read the result.

What an Ultrasound Shows in Dogs and Cats

Most often an abdominal ultrasound is done: liver, gallbladder, spleen, kidneys, bladder, GI tract, adrenal glands. Separately, a heart ultrasound (echocardiography) for murmurs, coughing, breathlessness. Ultrasound shows structure (size, shape, masses, fluid, stones) but not organ function — that is assessed by blood tests, so the methods complement each other.

Why a Pet Is Referred for an Ultrasound

Typical reasons: vomiting and refusing food, changes in blood tests (for example rising kidney or liver markers — see dog blood test), suspected stones or obstruction, pregnancy monitoring, a routine check-up in older animals, heart murmurs.

How to Prepare a Dog or Cat for an Ultrasound

  • Abdomen: light fasting of 8–12 hours is preferred (shorter for small and young animals — check with the clinic) so gas and food do not block the view; sometimes you are asked not to let the pet urinate before a bladder scan.
  • Fur: the area is usually shaved — this is normal and needed for probe contact.
  • Calm: stress interferes; anxious animals sometimes need light sedation — the vet decides.

Common Phrases in the Report

Phrase What it usually means
Homogeneous structure, smooth contours Normal
Increased liver echogenicity Non-specific — assessed with blood tests
Calculi (stones) in kidneys/bladder Stones — needs the vet's plan
Free fluid in the abdomen The cause must be found
Thickened intestinal/stomach wall Inflammation or other — clarified
Mass / space-occupying lesion Needs further work-up (often biopsy)

"Diffuse changes" and "increased echogenicity" are non-specific descriptions, not a diagnosis: they are interpreted together with tests and the exam.

Heart Ultrasound (Echo) in Pets

Echocardiography is done for murmurs, coughing, fainting, breathlessness. It assesses heart chambers, valves and contractility — what a regular ultrasound and blood tests cannot show. In cats, cardiomyopathies often stay hidden for a long time, so echo matters when suspected.

When to See a Vet Urgently

Urgently — for free fluid with worsening condition, suspected obstruction or torsion, a large mass, an acute abdomen, severe breathlessness. If you have both tests and ultrasound, they are read together; feline blood norms are in cat blood test, and a common reason for ultrasound is covered in vomiting in dogs.

To understand your pet's ultrasound report in plain language, upload it (PDF or photo) to the pet imaging interpretation service: the AI will explain the phrasing for the species. This helps you understand the result but does not replace a vet.

This article is informational. Diagnosis and treatment of your pet are the job of a veterinarian.

Frequently asked questions

  • Usually yes: the area is shaved so the probe sits tightly against the skin — without it ultrasound passes poorly and the image is unclear. It is painless and temporary. For some areas and short-haired animals, wetting the fur with gel may be enough, but the vet decides.

  • Light fasting of 8–12 hours is preferred (shorter for puppies, kittens and small animals — check with the clinic): food and bowel gas worsen the view of the pancreas and other organs. Sometimes you are asked not to let the pet urinate before a bladder scan. Water is usually allowed.

  • It is a non-specific description: the liver tissue looks brighter than normal. Various causes can lie behind it, so the phrase is interpreted not alone but together with blood tests (liver markers) and symptoms. On its own it is not a diagnosis.

  • Ultrasound shows organ structure (shape, size, masses, stones, fluid), while a blood test shows function (liver, kidneys, metabolism, inflammation). They are complementary: for example, rising kidney markers in blood plus kidney changes on ultrasound give a fuller picture than either alone.

  • Yes, to understand the report. Upload the protocol or image (PDF or photo) to the pet imaging interpretation service — the AI will explain the phrasing for the species in plain language. This helps you understand the result, but the final diagnosis and treatment are the vet's.

For informational purposes only

This article is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Please consult a healthcare professional for medical guidance.

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