Ultrasound-Guided Procedures for Dogs & Cats
When imaging identifies a mass, enlarged lymph node, organ abnormality, or fluid accumulation, the next diagnostic step often requires obtaining a tissue or fluid sample. Ultrasound-guided procedures allow our radiologists to precisely target the area of interest in real time — improving sample quality and diagnostic accuracy while minimizing risk.
At Sage Veterinary Imaging (SVI), our board-certified radiologists perform a full range of ultrasound-guided sampling and drainage procedures, providing your veterinarian with the cytologic or histopathologic information needed to guide treatment decisions.
SVI offers ultrasound-guided procedures at our centers in Round Rock, Texas; Spring, Texas; and Sandy, Utah.
Procedures We Perform
Our ultrasound-guided procedures combine real-time imaging precision with minimally invasive sampling techniques. These procedures typically complement a diagnostic ultrasound examination, allowing simultaneous evaluation and sample collection.
Fine-Needle Aspiration (FNA)
Fine-needle aspiration is the most common ultrasound-guided procedure. A thin needle is advanced into the target under real-time ultrasound visualization, and cells are aspirated for cytologic analysis. FNA can be performed on virtually any visible structure — liver masses, splenic nodules, enlarged lymph nodes, kidney lesions, adrenal tumors, and more. The procedure is minimally invasive, carries low complication risk, and often provides a definitive diagnosis within 24–48 hours.
Learn more about ultrasound-guided FNA →Core Needle Biopsy
When cytology from FNA is inconclusive or when tissue architecture is needed for diagnosis (particularly for differentiating lymphoma subtypes, characterizing liver disease, or grading tumors), core needle biopsy provides a small tissue sample for histopathologic analysis. Ultrasound guidance ensures the needle targets the correct lesion and avoids major blood vessels. Core biopsies provide significantly more diagnostic information than FNA and can be performed with minimal sedation.
Learn more about core biopsy →Abdominocentesis & Fluid Drainage
Abnormal abdominal fluid accumulation can indicate heart failure, liver disease, cancer, infection (septic peritonitis), or urinary tract rupture. Ultrasound-guided abdominocentesis allows safe and targeted fluid collection for analysis. Fluid cytology, protein measurement, and culture can distinguish between transudates, modified transudates, exudates, and hemorrhagic effusions — narrowing the diagnosis and guiding immediate treatment.
Learn more about abdominal fluid analysis →Pericardiocentesis
Pericardiocentesis — drainage of fluid from around the heart — is a life-saving emergency procedure for cardiac tamponade. Ultrasound guidance ensures the needle enters the pericardial space safely, avoiding the heart, lungs, and coronary vessels. Real-time visualization allows controlled fluid removal while monitoring cardiac function. The fluid is submitted for analysis to help identify the underlying cause, most commonly hemangiosarcoma or idiopathic pericarditis.
Learn more about pericardiocentesis →Cystocentesis & Targeted Sampling
Ultrasound guides precise sampling of the urinary bladder (cystocentesis for sterile urine culture), gallbladder (bile sampling for culture in suspected cholangitis), cysts (drainage and fluid analysis), and abscesses (drainage and culture). Real-time visualization ensures the needle reaches the intended target and avoids surrounding structures, making these procedures safer and more accurate than blind techniques.
Learn more about targeted sampling →Breeds Commonly Affected
Ultrasound-guided procedures are performed across all breeds and species. Dogs with splenic or hepatic masses (common in German Shepherds, Golden Retrievers, and Labrador Retrievers) frequently benefit from guided FNA for pre-surgical diagnosis. Cats with renal or intestinal masses often require guided sampling for lymphoma diagnosis and subtyping. Small-breed dogs with cardiac masses benefit from guided pericardiocentesis when tamponade develops.
Why Ultrasound Guidance Matters
Ultrasound guidance transforms diagnostic sampling by providing real-time needle visualization. The radiologist watches the needle advance toward the target on the ultrasound screen, confirming accurate placement before collecting the sample. This precision improves diagnostic yield (getting the right cells from the right place), reduces sampling error, and minimizes complications like bleeding from missed blood vessels.
Our board-certified radiologists perform all guided procedures personally, combining their imaging expertise with technical sampling skill. Cytology samples are prepared on-site for rapid submission, and preliminary in-house review can often provide same-day guidance for urgent cases.
What to Expect During Your Visit
Most ultrasound-guided procedures take 15–30 minutes and are performed during or immediately following a diagnostic ultrasound exam. FNA is often performed with only local anesthesia or light sedation. Core biopsies and drainage procedures may require moderate sedation. Your veterinarian will advise on the appropriate preparation.
Cytology results from FNA are typically available within 24–48 hours. Histopathology from core biopsies takes 5–7 business days. For urgent cases, rush processing can be arranged. Preliminary same-day cytologic impressions are often available for critical decisions.
Learn more about veterinary ultrasound at Sage →Why Choose Sage Veterinary Imaging
Get Answers for Your Pet
If your pet has a mass, enlarged organ, abnormal lymph nodes, or fluid accumulation that needs further evaluation, ultrasound-guided sampling can provide a minimally invasive diagnosis and guide your veterinarian’s treatment plan.
Schedule an Ultrasound-Guided Procedure
Visit one of our three locations to learn more and schedule your pet’s imaging study and guided sampling.
Ultrasound-Guided Procedures FAQ
Related Resources
Ready to Get Answers?
Ultrasound-guided sampling can provide a minimally invasive diagnosis for your pet’s condition. Visit one of our locations to get started.