Ultrasonographic visualization of the liver in sites recommended for blind percutaneous liver biopsy in horses.

This study investigates the reliability of suggested sites for blind percutaneous liver biopsy procedures in middle-aged horses. The findings indicate that most horses didn’t show clear ultrasonographic images of the liver at recommended biopsy spots and even when visible, the liver was often obscured by other organs or too thin for safe sampling, leading to the conclusion that blind percutaneous liver biopsy is not recommended in horses due to the risk of serious complications.

Research Goals

• The study aimed to explore the frequency of ultrasonographic detection of the liver at recommended sites for blind percutaneous liver biopsy in middle-aged horses.
• The researchers also sought to identify if the liver was obstructed by other organs or was too thin for a safe biopsy at these suggested locations.

Methods

• The study involved a prospective case series of 36 Quarter Horses or Quarter Horse crosses aged between 3 and 18 years old. All horses were essentially healthy, with any showing signs of liver dysfunction based on a serum biochemical analysis being excluded from the study.
• The region below a line drawn between the dorsal aspect of the horses’ tuber coxae (hip bone) and their elbow joint in the right 11th, 12th, 13th and 14th intercostal spaces (ICSs) were examined using ultrasonography to identify the liver.
• In each ICS, the thickness of the liver and whether viewing the liver was partly obstructed by other body organs were noted.

Results

• Only 39% (14/36) of horses had their liver imaged on ultrasonographic examination in all the 11th to 14th ICSs.
• None of the 36 horses had a liver of sufficient thickness (i.e., liver thickness ≥ 3.5 cm) for biopsy in all the imaged ICSs.
• For the 22 horses where the liver was not visible on ultrasonographic examination of an ICS, the lung was imaged instead in 12 (55%) horses, the intestine in 8 (36%), and both intestine and lung in 2 (9%).

Conclusions

• The researchers concluded that blind percutaneous liver biopsy in horses is not advisable due to the potential risk of serious implications, as the study showed inadequate liver imaging and obstruction or thinness of the liver tissue in most horses.