Transthoracic Needle Aspiration (TTNA)
A small needle is used to obtain lung
tissue for biopsy.
How is the test performed?
- You lie on a CT (CAT
scan) table. You will be positioned to make the area for biopsy
more easily accessible. You should maintain this position and refrain
from coughing during the biopsy. The skin is scrubbed and a local
anesthetic is injected.
A chest CT scan is used to locate the precise
spot of the biopsy.
- A small incision (about 1/8-inch) may be made in the skin, and
the biopsy needle is inserted into the abnormal tissue, tumor,
or lung tissue. A small specimen is removed with the needle and
sent to the laboratory for analysis.
- Pressure is placed over the site. Once bleeding has stopped,
a bandage is applied.
- A chest x-ray is obtained immediately after the biopsy.
- The procedure usually takes 30 to 60 minutes and laboratory (biopsy)
analysis usually takes a few days.
How the test will feel:
A lung needle biopsy is
preceded by a local injection of anesthetic, which will sting for
a moment. You will feel pressure and a brief, sharp pain when the
needle touches the lung.
Why the test is performed:
A needle lung biopsy
is performed when there is an abnormal condition that is near the
surface of the lung, in the lung itself, or on the chest wall. The
test is usually performed to diagnose relatively large abnormalities
seen on chest X-ray or CT scan. Most often, the abnormality is not
believed to be accessible by other diagnostic techniques, such as