Microwave technology is now widely used in a variety of medical applications. Most commonly microwave energy is used to create localised dielectric heating in order to desiccate human tissue - known as microwave ablation. Common medical areas of application include:
Microwaves have played an important role in the fight against cancer, providing a new way of treating the disease. Microwave ablation is commonly used in the removal of unwanted tissue masses, for example liver tumours, lung tumours and prostate ablation and also in the treatment of large tumours. Cancer patients who are poor surgical candidates can also benefit from microwave ablation, as it is minimally invasive.
A major benefit of microwave technology is flexibility - a wide range of medical applications can benefit from the range of frequencies available. For example, systems operating at 915MHz and 2.45GHz are ideally suited for large volume ablation, while the use of higher frequencies is suitable for treatments such as skin cancer, ablation of the heart to treat arrhythmia, uterine fibroids, multiple small liver metastases, corneal ablation (vision correction), spinal nerve ablation (back pain), varicose vein treatment, verrucae treatment and many other specific treatments. Higher frequency treatments in the range 5.8 GHz - 10 GHz can create shallow penetration of energy and are therefore ideal for surface based treatments or anything that requires very precise ablations. Microwaves can also be used to coagulate bleeding in highly vascular organs such as the liver and spleen.
One common preconception is that microwaves are difficult to control. The widespread use of standard industrial magnetron power generators in medical equipment and the trend of basing important measurements such as reflected power on ideal 50 ohm microwave components have historically led to a number of treatment issues.
While modern microwave systems have advanced significantly and can provide stable and reliable solid state sources, unreliability and uncertainty can arise when adopting this technology in the medical field. When using microwaves to treat any condition it is vital to take into account the changing dielectric properties of tissue. During treatment, these properties vary considerably therefore microwave applicators (antennas) are not always optimally matched to an ideal 50 ohms - resulting in significant mismatch.
This can create measurement uncertainty and VSWR problems. Any inaccuracy in these measurements has the potential to result in either insufficient power being delivered - resulting in poor treatments and a perception of unreliability, or excessive power being administered - inadvertently causing serious patient injury.
Emblation's safesweep® technology overcomes this problem in medical microwave applications. Our systems create a mismatch tolerant, controllable user experience that enhances patient safety and treatment reliability - the next generation for microwave ablation treatments.
To find out more about common safety issues and how we solve them,