Meaning and Definition of Scan

Definition of scan

A scan is a study of image on which are low doses of a radioisotope or radioactive isotope, mainly the Tecnesio 99, intravenously for later distribution in the skeleton as well as any specific organ.
This study is based on the fact that some tissues in pathological situations have a greater blood supply, the same cells that comprise them may show an increase in your metabolism. These two principles make to increase the uptake of the isotope by which one show a higher concentration in some areas of the body. The radioactivity emitted by the tissues is captured by a gamma camera that makes pictures of the bones which shows the distribution of the radiopharmaceutical, these images is what is known as the scan.
The scan is done mainly to study the bones, however is also used to determine the function of structures like the thyroid gland, kidneys and even heart.

Bone scan

The main indication for a bone scan is when you want to look for a primary tumor or a metastasis in bone, is a study that should be practiced in the people that the diagnosis of cancer has made in order to determine the degree of progress of the disease, particularly in those who tend to spread to bones , as occurs in the prostate cancer, breast cancer and thyroid cancer.
It is also useful to determine if there is an infection of bone, known as osteomyelitis or suspected a fracture that fails to be well displayed in an x-ray. It is also used to detect disorders of the metabolism of the bones that can weaken them.

Thyroid scan

Thyroid scan uses as radioisotope radioactive iodine which is captured by the thyroid gland. According to the emission of radiation pattern can be established if a goiter or a nodule, is felt by examining the patient or identified by a thyroid ultrasound, is solid or cystic nature. Also the degree of functioning of the gland (hypothyroidism or hyperthyroidism) can be seen.
One of the main indications of the thyroid scan is to identify the presence of malignant tumors of the thyroid.

Renal scan

The study of scan also is used to assess the State of functioning of the kidneys, especially in people who are allergic to contrast media used in studies such as the Urotac or urethrogram of elimination.
An important indication of this study is when you want to evaluate the State of functioning of the kidney after a kidney transplant, the scan also allows early identify conditions such as the rejection of the new organ.