Cryotherapy, also called cryosurgery, cryoablation, percutaneous cryotherapy, or targeted cryoablation therapy, is a minimally invasive treatment that uses extreme cold to freeze and destroy diseased tissue, including cancer cells.
Cryotherapy can be applied topically (on the skin surface), percutaneously, or surgically. Topical cryotherapy is typically used for skin and eye lesions. When the lesion is located below the skin surface, a needle-like therapy probe or applicator needs to be inserted into the skin. Sometimes, a surgical incision is required.
Interventional radiologists use image guidance techniques such as ultrasound, computed tomography (CT), or magnetic resonance (MR) to help guide cryoprobes to treatment areas within the body.
What are some common uses of interventional radiological diagnosis and treatments?
It can be used to recognize and treat tumors in the liver, kidneys, bones, lungs, and breasts, as well as masses in various body parts.
What diseases can be treated?
Cryotherapy is used to treat tumors in other parts of the body, such as skin tumors, cancerous skin patches, prostate, liver and cervical cancers, breast, kidneys, bones (including the spine), lungs, and other parts of the body, especially if surgical resection is not possible or as a non-surgical treatment option. Cryotherapy has been shown to be effective in selected patients, although more research is needed to determine its long-term effectiveness.
What kind of preparation does it require?
In the case of cryotherapy using a large, surgical incision (cryosurgery), a short hospitalization will be required. Percutaneous cryotherapy can be performed as an outpatient service, but may require a short overnight hospital stay.
What does the equipment look like?
Ultrasound, computed tomography (CT) or magnetic resonance (MR) imaging, cryoprobe may be used in this procedure.
It consists of a console with ultrasound scanners, computer and electronic devices. Ultrasound is an excellent method for some areas of the body, while other areas, especially the air-filled lungs, are inadequate for ultrasound. For this, an angiography unit with tomography or tomography feature is needed. In addition, more detailed examination according to the location and condition of the tumor and, if necessary, an MRI unit can be used.
How does the procedure work?
Cryotherapy uses nitrogen or argon gas to create extreme cold to destroy diseased tissue. Liquid nitrogen is applied directly with a cotton swab or spray device to destroy diseased tissue located outside the body. For tumors located below the surface of the skin and deep in the body, the doctor will use image guidance to insert one or more applicator needles or cryoprobes through the skin into the area of diseased tissue and then deliver liquid nitrogen or argon gas.
Living tissue, healthy or diseased, cannot withstand extreme cold or heat conditions and dies from:
Below about -40°C, intracellular lethal ice crystals begin to form, or above 57°C, air bubbles destroy almost any cell.
Cells die when their blood supply is blocked by the formation of ice or bubbles in small tumor blood vessels, causing clotting. Since the average blood clotting time is about 10 minutes, the extreme cold is maintained for at least 10-15 minutes to ensure that lethal ice temperature is reached. This time is very short in Laser and Microwave ablation. Direct observation of the ablation temperature is possible.
Because cryotherapy consists of a series of steps that lead to cell death, tumors are repeatedly frozen and thawed; typically two or more freeze-thaw cycles are used.
When the cells are destroyed, the immune system's white blood cells try to remove the dead tissue.
How is the procedure applied?
Percutaneous image-guided procedures, such as cryotherapy, are most often performed by a specially trained interventional radiologist in an interventional radiology unit or sometimes in the operating room.
This procedure is usually done on an outpatient basis. However, some patients may require hospitalization following the procedure.
For tumors that can be approached through the skin deep into the body, a percutaneous procedure is performed and inserts thin, needle-sized applicators or cryoprobes.
You may be connected to monitors that monitor your heart rate, blood pressure, and heart rate during the procedure.
You may be given a sedative medicine intravenously in your arm. Moderate sedation may be used. Alternatively, you may receive general anesthesia.
The area where the applicators or cryoprobe will be placed will be shaved, sterilized and covered with a sterile drape.
A very small skin incision is made in the area. Using imaging guidance, he or she will place one or more applicators or cryoprobes through the skin into the area of diseased tissue. When the applicators or cryoprobes are inserted, liquid nitrogen or argon gas is supplied. Besides cryoprobes, nothing else enters the body. An "ice ball" is created by a rapid drop in temperature at the tip of the probe. This causes all the water in the area at the tip of the probe to freeze. Imaging is used to guide the placement of the applicators and to monitor the freezing process. The "ice ball" can be visualized using ultrasound, CT, or MRI.
Some tumors require more than one applicator to freeze completely. For prostate cancer, six to eight applicators are inserted into the perineum (the tissue between the rectum and scrotum and penis) using ultrasound guidance.
At the end of the procedure, the applicator(s) is removed and pressure is applied to stop the bleeding. The opening in the skin is covered with a bandage. Usually, no stitches are needed.
The entire procedure
