Dog Ultrasounds: What Are They, and Why Would a Dog Need One?

Published May 30, 2024
A dog gets an ultrasound by their vet.

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What Are Dog Ultrasounds?

An ultrasound exam (ultrasonography) is a non-invasive imaging technology used to examine a dog’s internal organs and soft tissues.

An ultrasound machine uses sound waves to create an image of a part of your dog’s body. Ultrasound is used to examine the structure and movement of organs and can also be used to evaluate blood flow in an area.

An ultrasound exam is a common form of imaging performed in dogs, second only to X-rays. Specialty clinics and universities typically have an ultrasound machine, and access is increasing in general practices.

To perform an ultrasound exam, the veterinary professional simply places a probe on your pet’s body surface and evaluates the image that is transmitted to the screen.

To improve the image quality, the area of the dog’s body being scanned is usually shaved, and then ultrasound gel is applied. The gel provides better contact between the probe and the skin, allowing the sound waves to pass into the body without passing through air.

An ultrasound machine uses sound waves to create an image of a part of your dog’s body. Ultrasound is used to examine the structure and movement of organs and can also be used to evaluate blood flow in an area.

Some dogs rest comfortably for an ultrasound scan, but it’s not uncommon for them to need sedation if the scan is of a large area, such as the entire abdomen.

Types of Dog Ultrasounds

Types of dog ultrasound exams include:

  • Abdominal ultrasound: An abdominal ultrasound can be used to search the abdomen for abnormalities, or it can be performed on an emergency basis to detect bleeding within the abdomen or an intestinal blockage.

  • Echocardiogram: An echocardiogram is an ultrasound exam of the heart. This diagnostic test evaluates the heart chambers, blood flow through the heart, and the sac that encloses the heart (pericardial sac).

  • Single-organ ultrasound: A single-organ ultrasound is limited to one structure. For instance, a dog with blood in their urine may have a bladder scan, or a pregnant female dog may have her uterus scanned.

  • Thoracic ultrasound: Thoracic ultrasound is used to look at the lungs and the space around the lungs.

  • Soft-tissue ultrasound: Soft-tissue ultrasound is used to evaluate muscles, tendons, and ligaments.

Why Would a Dog Need an Ultrasound?

A dog may need an ultrasound for many reasons, such as:

  • Traumatic injury: An ultrasound may be used to look for free fluid in the abdomen, which could suggest issues such as internal bleeding or a ruptured bladder.

  • Cancer: Ultrasound can be used to identify masses within the abdomen, enlarged lymph nodes, and other changes that may suggest the pet has cancer.

  • Chronic vomiting and/or diarrhea: The gastrointestinal tract may be scanned to look for causes of vomiting and diarrhea.

  • Urinary tract issues: The bladder and kidneys can be scanned for stones or masses.

  • Pregnancy: The uterus can be scanned to diagnose pregnancy, determine the number of fetuses, and monitor fetal development and viability.

  • Heart disease: An echocardiogram is the standard test for diagnosing and monitoring heart disease.

  • Abnormal lab work or chronic illness: Ultrasound may be used to identify changes to organs that could explain abnormal lab results or chronic illness.

Risks of Dog Ultrasounds

An ultrasound carries minimal risk. Sound waves are not dangerous, and no radiation is involved.

The most serious risk of an ultrasound involves its use for guiding biopsies.

For instance, if an abnormality is seen in the liver, a needle can be inserted into the abdomen with ultrasonographic guidance to collect a sample from the abnormal tissue. This carries the risk of potentially lacerating an organ or blood vessel, leading to hemorrhage.

Other risks include skin irritation from shaving or gel application, and complications from sedation (if needed).

Benefits of Dog Ultrasounds

The benefits of dog ultrasounds include:

  • Real-time imaging

  • Non-invasive technique

  • Often performed without sedation

  • No radiation exposure

  • Detailed images for assessing soft tissues

  • Ability to monitor blood flow if the ultrasound unit has Doppler capabilities

Effectiveness of Dog Ultrasounds

Dog ultrasounds are highly effective for looking at the structure and movement of soft tissues and most organs.

However, they’re not useful for evaluating air-filled organs such as healthy lungs.

Dog ultrasounds are highly effective for looking at the structure and movement of soft tissues and most organs.

In addition, they’re not useful for imaging bones or tissues encased in bone, such as the brain or spinal cord, because sound waves cannot pass through bone.

Cost of Dog Ultrasounds

A dog ultrasound usually costs between $300 and $600. Quick one-organ scans or pregnancy diagnosis scans typically cost less. The cost may increase if your dog is large or requires sedation.

Pet insurance typically covers ultrasounds if they’re recommended by a veterinarian for diagnosis or monitoring of a condition that wasn’t pre-existing.

Accident-only insurance may cover an ultrasound if it’s recommended for a pet who has a traumatic injury, ingested a foreign object, or otherwise injured themselves accidentally. Pregnancy-related ultrasounds are often not covered by pet insurance since pregnancy is preventable.

Preparation for Dog Ultrasounds

Ultrasounds for dogs don’t usually require at-home preparation.

At the veterinary hospital, the veterinary staff shaves the area on your pet’s body that requires scanning and applies ultrasound gel. If your pet can’t relax, the veterinary team may sedate them to facilitate the exam.

If you know your pet is anxious, speak with your veterinarian about anti-anxiety medications, such as trazodone, gabapentin, acepromazine, or melatonin, which can be given to your pet prior to the scan to facilitate the procedure.

Alternatives to Dog Ultrasounds

Other imaging modalities may be used in place of an ultrasound. X-rays don’t provide real-time dynamic imaging like ultrasound, but they’re generally more affordable and can provide an image of bones.

CT and MRI scans can also be used to image soft tissue and bones. These alternatives are pricier and require anesthesia, but they provide more detailed images. They are the best options for imaging the brain and spinal cord.

Dog Ultrasounds FAQs

What does a dog ultrasound show?

A dog ultrasound shows the structure and movement of soft tissues in real time. If the ultrasound has Doppler capability, it can also show blood flow to an area.

Ultrasounds are not good for imaging bones, organs encased in bone (e.g., the brain), or air-filled organs.

Do dogs have to be sedated for an ultrasound?

Many dogs do well for ultrasounds without sedation. However, anxious dogs may benefit from sedation to make the process easier on them and the veterinary team.

Some scans, such as a full abdominal scan, can be lengthy, and sedation may help keep the dog still and calm.

If the veterinarian collects a biopsy sample of an organ with ultrasound guidance, sedation is recommended to reduce the risk of injury and pain to the pet.

When should I get an ultrasound for my dog?

Ultrasounds are recommended for various disease processes such as heart disease, trauma, and chronic gastrointestinal disease.

Ultrasound is typically used to diagnose a condition or monitor treatment progress (e.g., looking at lymph nodes in a dog undergoing chemotherapy).


Rhiannon Koehler, DVM

WRITTEN BY

Rhiannon Koehler, DVM

Veterinarian

Dr. Rhiannon Koehler is a veterinarian and freelance medical writer. She received her Doctor of Veterinary Medicine and Master of Public...


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