Diagnostic imaging tests are very useful in detecting mediastinal diseases. Thoracic surgery specialists state that they are a non-invasive and completely painless way to visualize images of organs and identify possible anomalies in the patient’s body.
In the case of the mediastinum, most of the diseases have no previous symptomatology, so that sometimes a chest X-ray can show lesions and traumas that were previously ignored, whose diagnosis will be complete only after some imaging tests.
What is the mediastinum?
The mediastinum is the anatomical compartment of the thorax that lies between the two pleural cavities, and contains all the thoracic organs except the lungs. Very often, masses (tumorous or cystic) or infections (acute or chronic) can settle in the mediastinum. These masses can represent different pathologies, including thymomas, lymphomas, intrathoracic goiters, teratomas or neurofibromas.
What to do in case of injury or trauma?
After a discovery of this type, it is highly advisable to carry out additional studies and that the specialist performs an evaluation of the patient’s clinical history, considering his age, symptoms, location and size of the mass found.
The presumptive diagnosis is made after careful imaging tests, which provide an optimal definition of the lesions present in the mediastinum and their relationship with neighboring organs. CT-guided or surgical needle biopsy establishes the definitive diagnosis.
Main diagnostic imaging tests for diseases of the mediastinum
- CT or Scanner: Also called CT or Computed Tomography, it is the imaging test most commonly used in the diagnosis of mediastinal tumors. It is a very complex machine, consisting of a bed on which the patient is placed, and an X-ray tube that rotates at high speed to acquire information of the entire volume of the patient’s body.
- Magnetic Resonance Imaging (MRI): An MRI is an imaging test that uses very powerful magnets and radio waves to create images of the body, without using X-rays or radiation. It is indicated to differentiate between mediastinal tumors of vascular or bronchial origin. It is used to evaluate tumor invasion of the heart, great vessels, chest wall and spine. It is also more accurate than CT in distinguishing solid tumors from cysts.
- PET: Positron emission tomography (PET) differs from the other techniques mentioned above because it can show chemical and physiological changes related to metabolism, and therefore these images can show abnormalities and changes in tissues. First, a radiopharmaceutical, called an isotope, is injected into the patient. Then an amount of X-rays through the patient’s body helps to determine the details of cellular metabolism. PET is very useful for predicting the degree of malignancy of tumors, as well as for assessing the presence of residual disease after chemotherapy.
- Esophagogram: It is a study that consists of taking X-rays of the patient in various positions to obtain images of the esophagus, in order to determine changes in the normal anatomy. It is sometimes used to evaluate the mediastinal lesions that affect it.
- Digital angiography: It is a test whose function is the study of circulatory vessels that are not visible by conventional radiological examinations. It is used in some neurogenic tumors with intraspinal extension, and can replace MRI.
- Gamma-graphic studies: There are three types of gamma-graphic studies:
- Iodine scintigraphy, used in the study of endothoracic goiter or thyroid carcinoma metastases.
- Gallium scintigraphy, which is used to evaluate acute and chronic mediastinal infections.
- Technetium scintigraphy can be used to identify gastric mucosa in neuroenteric cysts of the visceral compartment.