Transthoracic puncture-biopsy or TTP

Transthoracic puncture-biopsy is an examination that consists of introducing a long needle (sterile and single-use) through the thorax after local anesthesia to a lesion in order to remove a small tissue fragment. The location of the lesion is done under radiological control by computer tomography scan (CT) scan in most cases or by scopy.

TTP is a diagnostic procedure aimed to determine the nature of an abnormal formation in the chest.

The examination may take 10 to 30 minutes depending on the difficulty of lesion identification.

You must fast 3 hours before the exam. Except for anticoagulant treatments, you can continue to take your usual medications.

The examination is performed under local anesthesia. If necessary, a cough suppressant and a sedative can be taken as well.

A sterile, single-use needle is inserted into the lesion following local anesthesia. A small fragment is then taken for cytological (using a fine 0.8 mm diameter needle) and possibly histological (using a larger 2mm needle in this case) or bacteriology analyses.

After the puncture, you must stay in bed for about 30 minutes. Relative rest is then recommended for several hours. This examination requires an overnight stay in hospital (for observation). A chest X-ray is taken the day after the puncture, mainly to make sure that there is no pneumothorax.

Discomfort such as a vagal reaction is rather rare with premedication (cough suppressant and sedative). Bloody sputum may occur during or after the examination, which is generally not serious, disappearing spontaneously.

A pneumothorax can occur, if the lesion location requires to cross a part of the lung (= detachment of the lung from the chest wall), this can remain asymptomatic or manifest itself by pain or difficulties to breathe in the most serious cases; a more important pneumothorax may require either the evacuation of the air present around the lung with a needle (or exsufflation), or the placement of a suction drain within the thorax until the small breach in the lung is closed, which mostly takes 24-48 hours.

Coagulation disorders and very severe respiratory insufficiency are contraindications to this examination.