Ultrasound-Guided Aspirates
in Dogs and Cats
What Is an Ultrasound-Guided Aspirate?
An ultrasound-guided aspirate involves using real-time ultrasound imaging to guide a fine needle into a specific organ, mass lymph node, or fluid collection. Gentle suction is applied to collect cells, which are then examined under a microscope or sent to a laboratory for analysis.
The procedure is commonly referred to as a fine-needle aspirate (FNA) and is considered a minimally invasive way to obtain diagnostic information. Ultrasound guidance allows the veterinary team to visualize the needle as it enters the target area, helping improve accuracy and safety.
Why It May Be Recommended
Ultrasound-guided aspirates are recommended when imaging reveals a finding that cannot be fully characterized by appearance alone. Sampling cells often helps determine whether a change is inflammatory, infectious, benign, or cancerous.
Common reasons for performing an ultrasound-guided aspirate include:
- Abnormal masses within abdominal organs
- Enlarged lymph nodes
- Thickened intestinal walls
- Liver, spleen, or kidney abnormalities
- Fluid collections requiring further evaluation
In many cases, aspirates provide enough information to guide treatment decisions without the need for more invasive procedures.
How the Procedure Is Performed
Most ultrasound-guided aspirates are performed with the pet awake or lightly sedated, depending on comfort, temperament, and the area being sampled.
The procedure typically involves:
- Clipping and cleaning the skin over the sampling site
- Using ultrasound to precisely locate the target area
- Guiding a very small needle into the area of interest
- Collecting a sample of cells
- Removing the needle immediately after sampling
Because the needle used is very small, tissue disruption is minimal and the procedure usually takes only a few minutes.
What the Samples Can Tell Us
Cells collected during an ultrasound-guided aspirate can provide valuable insight into what is happening inside your pet’s body.
Results may reveal:
- Inflammatory or infectious processes
- Reactive or benign tissue changes
- Certain types of cancer
- Evidence of organ-specific disease
In some cases, aspirates provide a clear diagnosis. In others, the results help determine whether additional testing – such as biopsy or advanced imaging – is recommended.
What to Expect After the Procedure
Ultrasound-guided aspirates are considered very safe when performed by trained veterinary professionals. Because ultrasound allows real-time visualization of the needle, veterinarians can avoid major blood vessels and surrounding structures.
Complications are uncommon and typically mild, such as temporary soreness and minor bruising at the needle site. Serious complications are very rare.
Most pets recover immediately after an ultrasound-guided aspirate and can usually resume normal activity the same day. Results may be available the same day or within several days, depending on whether samples are evaluated in-house or sent to a reference laboratory. Your veterinarian will review the findings with you and explain how the results help guide the next steps in your pet’s care.
Our Approach at VSP
Ultrasound-guided aspirates allow our team to gather critical diagnostic information while keeping procedures as minimally invasive as possible.
Our Internal Medicine and Diagnostic Imaging teams use ultrasound-guided aspirates as part of a stepwise, patient-centered diagnostic process. By combining advanced imaging with targeted sampling, VSP can often shorten the diagnostic timeline and help pets begin appropriate treatment sooner.
Our goal is always to obtain the information needed to guide care while minimizing any discomfort and risk for your pet.
Need Answers About an Abnormal Finding on Ultrasound?
If imaging has identified a mass, enlarged organ, or area of concern, ultrasound-guided aspirates can help provide answers while minimizing discomfort for your pet.
Call us to speak with our team or schedule an evaluation for your pet.
Frequently Asked {Questions}
What is an ultrasound-guided aspirate used for in dogs and cats?
An ultrasound-guided aspirate is used to collect cells from internal organs, masses, lymph nodes, or fluid collections. Examining these cells helps determine whether a finding is inflammatory, infectious, benign, or cancerous, which helps guide treatment decisions for your pet.
Is an ultrasound-guided aspirate the same as a biopsy?
No. An ultrasound-guided aspirate collects individual cells using a very small needle, while a biopsy removes a small piece of tissue. Aspirates are less invasive and are often performed first to determine whether more advanced testing, like a biopsy, is necessary.
Is an ultrasound-guided aspirate painful for my pet?
Most pets tolerate ultrasound-guided aspirates very well. The needle used is very small, and the procedure is brief. Some pets may feel mild pressure, but significant discomfort is uncommon. Light sedation may be used when needed to reduce stress or movement.
Does this procedure require anesthesia?
General anesthesia is usually not required. Many aspirates are performed while pets are awake or lightly sedated, depending on temperament and the area being sampled. This helps reduce risk while keeping pets comfortable.
How long does an ultrasound-guided aspirate take?
Once the target area is identified on ultrasound, the aspirate itself usually takes only a few minutes. The full appointment may take longer to allow time for imaging, sample preparation, and monitoring.
How quickly will we get results?
Some samples can be evaluated the same day, especially when initial review is performed in-house. Other samples may be sent to a reference laboratory, with results typically available within a few days. Your veterinarian will discuss findings and next steps as soon as results are available.
Are there risks associated with ultrasound-guided aspirates?
Ultrasound-guided aspirates are considered very safe when performed by trained veterinary professionals. Minor bruising or temporary soreness at the needle site is uncommon, and serious complications are rare because ultrasound allows precise needle placement.
What happens if the aspirate does not provide a clear diagnosis?
If results are inconclusive your veterinarian may recommend additional testing. This could include repeat aspirates, ultrasound-guided biopsy, advanced imaging, or monitoring over time. Each recommendation is tailored to your pet’s specific situation and medical needs.
What is the prognosis for dogs with Cushing's disease?
With accurate diagnosis and ongoing management, the outlook for most dogs is very good. Many patients show noticeable improvements in energy, comfort, and daily activity once treatment is properly adjusted.