A gamma probe is a handheld device used with a Geiger-Muller tube or scintillation counter, for intraoperative use following interstitial injection of a radionuclide, to locate regional lymph nodes by their radioactivity. It is used primarily for sentinel lymph node mapping and parathyroid surgery.

History

The sentinel node market experienced high growth during the last 10 years starting with melanoma sentinel node surgical search and breast cancer sentinel node staging; both are currently considered standards of care. Most surgeons propose node staging after a positive breast biopsy. New applications are being developed for parathyroid direct detection and intra-operative detection of cancerous tissue using tumor-seeking radiopharmaceuticals. Parathyroid detection is growing fast, while the intraoperative use of gamma probes for direct tumor detection is just emerging.

Quality Criteria

To evaluate the quality of a gamma probe system one must measure or discuss the following parameters:

1. Spatial selectivity
2. Spatial resolution
3. Maximum sensitivity
4. Quality of shielding
5. Energy resolution and spectral discrimination
6. Display of signal

Competition

The following companies manufacture gamma probes:

Company	Device Control Unit	PET Capable	Origin Country	Company Website	Worldwide Market Share
RMD Instruments	Navigator	yes	MA, USA	rmdmedical.com	45%
NeoProbe	Neo 2000	yes	OH, USA	Neoprobe.com	35%
Care Wise Medical	C-Trak	yes	CA, USA	carewise.com	15%
CLERAD	Gamma Sup	yes	France	clerad.fr	5%
IntraMedical Imaging	Node Seeker	yes	CA, USA	gammaprobe.com	1%
Eurorad SA	Euro Probe	?	Germany	em-instruments.com	1%
World of Medicine	Gamma Finder	?	Germany	gammafinder.com	1%
Nucleo Med (Pol.Hi.Tech)	Nucleo Probe	?	Italy	scintiprobe.com	1%
DeLong Instruments	DiSurpro	?	Czech Republic	dicomps.com	<1%
Nuclear Lab	DGC II	?	Argentina	nuclearlab.com	<1%
GFE Service	Gamma Locator DXI	yes	Germany	gfe-service.de	<1%
Crystal Photonics GmbH	Crystal Probe	yes	Germany	surgicalprobe.com Crystal-Photonics.com	<1%
Silicon Sensor Intl.	SIS System	yes	Germany	silicon-sensor.com	<1%
Gammasonics	Gamma Probe Explorer	yes	Australia	gammasonics.com	<1%

Isotopes for clinical use with Gamma Probes

1. Tc99m - Technetium-99m
2. I125 - Iodine 125
3. I131 - Iodine 131
4. I111 - Indium 111
5. F18 - Fluorine 18
6. Ga68 - Gallium 68

See also

• Nuclear medicine
  Nuclear medicine
  In nuclear medicine procedures, elemental radionuclides are combined with other elements to form chemical compounds, or else combined with existing pharmaceutical compounds, to form radiopharmaceuticals. These radiopharmaceuticals, once administered to the patient, can localize to specific organs...
  
  
• Gamma camera
  Gamma camera
  A gamma camera, also called a scintillation camera or Anger camera, is a device used to image gamma radiation emitting radioisotopes, a technique known as scintigraphy...
  
  
• Positron emission tomography
  Positron emission tomography
  Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...
  
  
• Molecular Imaging
  Molecular imaging
  Molecular imaging originated from the field of radiopharmacology due to the need to better understand the fundamental molecular pathways inside organisms in a noninvasive manner.- Overview :...
  
  
• Sentinel lymph node
  Sentinel lymph node
  The sentinel lymph node is the hypothetical first lymph node or group of nodes reached by metastasizing cancer cells from a primary tumor.-Physiology:...
  
  

External links

• Video on SLN
• Video on Sentinel Node Mapping in Melanoma