Gamma probe

Gamma Probe

A typical gamma probe used in medical procedures.

A gamma probe is a medical device used in nuclear medicine to detect gamma radiation. It is commonly used in sentinel lymph node biopsy and other procedures where the detection of radioactive tracers is necessary. The device is handheld and allows surgeons to locate tissues that have absorbed a radioactive substance, aiding in the identification and removal of specific tissues during surgery.

Functionality

The gamma probe operates by detecting gamma rays emitted from a radioactive tracer that has been introduced into the body. The most commonly used tracer is Technetium-99m, a radioisotope that emits gamma radiation. The probe consists of a scintillation detector or a semiconductor detector that converts the gamma radiation into an electrical signal, which is then processed and displayed to the user.

Applications

Gamma probes are primarily used in:

• Sentinel lymph node biopsy: This is a procedure used in oncology to determine the extent of cancer spread. The gamma probe helps identify the sentinel lymph nodes, which are the first nodes to receive drainage from a cancerous tumor.
• Radioguided surgery: In this application, the gamma probe assists surgeons in locating and removing cancerous tissues that have absorbed the radioactive tracer.
• Parathyroid surgery: Gamma probes are used to locate hyperactive parathyroid glands by detecting the uptake of radioactive tracers.

Advantages

The use of gamma probes in medical procedures offers several advantages:

• Minimally invasive: The probe allows for precise localization of tissues, reducing the need for extensive surgical exploration.
• Real-time feedback: Surgeons receive immediate information about the location of radioactive tissues, improving the accuracy of the procedure.
• Reduced operative time: By quickly identifying target tissues, gamma probes can decrease the duration of surgery.

Limitations

Despite their benefits, gamma probes have some limitations:

• Limited depth penetration: The effectiveness of gamma probes decreases with the depth of the target tissue.
• Background radiation: The presence of background radiation can interfere with the detection of the target signal.
• Cost: The use of radioactive tracers and specialized equipment can increase the cost of procedures.

Related pages

• Nuclear medicine
• Sentinel lymph node biopsy
• Radioguided surgery
• Technetium-99m