Ultrasound-guided fine needle aspirates are useful for characterizing the cell type of many of the neoplasms found on the ultrasound scan, especially lymphoma, mastocytosis, or histiocytosis. Aspirating small free fluid pockets in the chest or abdomen is safer and easier with ultrasound guidance.


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From Atlas of Small Animal Ultrasonography by Dominique Penninck and Marc-Andre d’Anjou. Blackwell Publishing. 2008.

Ultrasound is very useful to aid diagnostic or therapeutic thoracocentesis, especially if only a small volume of pleural effusion is present. Additionally, fine-needle aspiration or biopsies of thoracic mass lesions are commonly performed. These procedures are safe and have a high diagnostic yield (Wood it al.1998).


Pericardiocentesis (PC) is both a therapeutic and diagnostic procedure.


Fine-needle aspiration of the spleen is routinely performed and is particularly useful in the diagnosis of diffuse infiltrative disorders.


[Renal] Neoplastic processes, such as lymphoma, are usually diagnosed on a cytological specimen obtained with fine-needle aspiration….[and] can sometimes require a biopsy…..Fine-needle drainage of cavitary lesions, such as cysts or abscesses, can also be performed as a diagnostic and/or therapeutic procedure. In place of excretory urography, fine-needle aspiration of a distended pelvis (pyelocentesis)can be performed and followed by intrapelvic injection of iodine-based contrast medium (Rivers et al. 1997)


Percutaneous ultrasound-guided fine-needle aspiration and automated micro core biopsy of GI lesions are safe alternative procedures to use instead of endoscopic or surgical biopsy. …….They are especially useful when lesions are not accessible endoscopically…In presence of a GI lesion associated with regional lymphadenopathy, it is recommended to target both structures to increase the chance of obtaining one or more diagnostic sample.
Fine-needle aspiration of peritoneal fluids is used routinely…..even small amount of fluids can be securely aspirated. Abdominal masses and lymph nodes can also be aspirated or biopsied. Cavitated masses, abscesses, or cysts can also be drained with ultrasound guidance.


Ultrasound-guided fine-needle aspirations and biopsy have become routine procedures complementing hepatic ultrasonography (Penninck and Finn-Bodner 1998)…Vacuolar hepatopathies, such as lipidosis and hyperadrenocorticism, are reliably diagnosed through cytological specimens obtained with fine-needle aspiration (Wang et al. 2004)…Some neoplastic processes, such as lymphoma, and inflammatory processes can also be diagnosed through cytological examination, although a more confident diagnosis may require biopsy. Fine-needle drainage of cavitary lesions, such as cysts or abscesses, can also be performed as a diagnostic and/or therapeutic procedure…Ultrasound-guided cholecystocentesis can be used to obtain a sample of bile for culture or for GB decompression in animals with extra hepatic biliary obstruction…


…ultrasound-guided suction biopsy are the preferred methods of confirming bladder or urethral neoplasia…red rubber catheter with side holes is connected to a 20-mL syringe and is placed aseptically into the urinary bladder…The catheter tip is visualized is within the urinary bladder (by ultrasound)…be positioned adjacent to the bladder mass…to be biopsied.


Percutaneous fine-needle aspiration or biopsy of the prostate is easily performed…drainage of prostatic abscesses and in situ injection of antibiotics is a valid alternative method to surgical intervention,…


From Small Animal Diagnostic Ultrasound by Nyland and Matoon. W.B.Saunders. 2002

Percutaneous ultrasound-guided biopsy is one of the most valuable uses of ultrasonography in small animals. It is rapid, safe, and relatively noninvasive and yields a high percentage of superior diagnostic samples.