A biopsy needle is a medical tool used to extract tissue samples for diagnostic or therapeutic purposes. There are several types of biopsy needles, including coaxial, semi-automatic, automatic, bone marrow, and pleural biopsy needles.

Coaxial needles are composed of two concentric needles, with the outer needle used to guide the inner needle to the biopsy site. Semi-automatic biopsy needles are manually inserted into the biopsy site, and the needle is triggered to collect the tissue sample. Automatic biopsy needles are spring-loaded, allowing for quick and easy tissue extraction.

Bone marrow biopsy needles are designed to extract samples from the bone marrow for diagnostic purposes. Pleural biopsy needles are used to collect tissue samples from the lining of the lungs and chest cavity.

Overall, biopsy needles are crucial tools in the diagnosis and treatment of various medical conditions, providing medical professionals with essential information for accurate diagnosis and treatment planning.