Torres, M. 2014. Refining methods for mouse hepatic biopsy. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 557-558 (Abstract #P32).

The mouse is a commonly used species in liver research such as oncology, toxicology, and disease models. The ability to collect specimens of liver is vital to such research. Such studies require either a major surgical procedure or euthanasia to obtain a liver biopsy. Ultrasound-guided biopsy proves to be a less invasive method of obtaining histologic assessments of hepatocytes. In this study, 3 groups of mice were used, an ultrasound, surgical, and a terminal group with 10 mice per group. The use of ultrasound to obtain a liver biopsy is quicker, complete set up and biopsy via ultrasound averages 15 min as opposed to the surgical method which averaged 30 min. Ultrasound biopsy technique also proved to be safer; although no animals from either survival group showed complications in this study, the US group recovered quicker than the surgical group. Another benefit was the ability to view the liver prior to obtaining a biopsy. Although not a factor in our study, this can be useful for other studies in which the condition of the liver may be a factor in obtaining samples therefore reducing the number of animals needing surgery to assess the liver. Although ultrasound-guided liver biopsy is routinely performed in other species it can be a challenge to perform in mice. The smaller size of the mouse can make it a challenge to locate the liver lobe prior to introduction of the needle. Thermoregulation in mice is also a challenge when using the US gel for imaging. Mice must be monitored closely to ensure they are maintaining appropriate and consistent body temperature. Hemostatsis is also a challenge and is most successful by applying slight digital pressure. Mice from the survival groups were monitored for 8 h postprocedure as required by the protocol and any/all complications noted.