Biopsy

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Biopsy, surgical removal of living body tissue for study and diagnosis with a microscope. Biopsies are performed on organs to analyze the cause and nature of disease, and on tumors, or abnormal tissue growths, to determine if they are a type of cancer. For patients diagnosed with certain diseases, follow-up biopsies are used to study the effectiveness of a chosen course of medical treatment. Biopsies are vital in diagnosing and monitoring a wide range of illnesses, including muscular dystrophy, characterized by gradual wasting away of skeletal muscle, and Crohn’s disease, the chronic inflammation of the intestines.

An external biopsy specimen is taken by cutting or scraping a piece of tissue from an affected area of skin. When a sample is needed from an area well below the surface of the skin, the procedure is called internal biopsy, and viewing techniques such as ultrasound or computer axial tomography are often used to help the physician guide a hollow needle to the exact location.

In a procedure called aspiration biopsy, a needle is attached to a hypodermic syringe. A tissue sample is collected in the barrel of the syringe by using the suction that is created when the plunger of the syringe is pulled out. In a needle biopsy, the tissue sample is collected by rotating the needle, trapping a small but sufficient amount of tissue within the needle itself. In a punch biopsy, a sharp-edged instrument is used to recover a round piece of tissue from a specific depth below the skin.

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