Energy-based ablation devices are powered by a wide variety of sources, resulting in a plethora of devices. These include electrical, radiation, light, radiofrequency, ultrasound, cryotherapy, thermal, microwave and hydromechanical. This array of technology enables the physician, with the appropriate device in hand, to pinpoint and destroy almost any kind of tissue, almost anywhere in the body.
Electrical. Electrical devices for the ablation of tissue include electrocautery devices, as well as devices used for ablating both soft and hard tissues. This category does not include devices which pierce without cauterizing, such as drills for piercing bone tissue.
Radiation. Radiation ablating devices include traditional radiotherapy machines, image-guided radiotherapy (IGRT) and intensity-modulated radiotherapy (IMRT).
Light. Light amplification by stimulated emission of radiation, or LASER (laser) ablation, also known as laser induced thermal therapy (LITT), uses high-intensity light to shrink or destroy tumors. Another light-based ablation technology is photodynamic therapy (PDT).
Radio frequency. Radiofrequency ablation devices work by sending alternating current through the tissue. This creates increased intracellular temperatures and localized interstitial heat. When temperatures exceed 60°C, cell proteins rapidly denature and coagulate, resulting in a lesion. The lesion can be used to resect and remove the tissue or to simply destroy the tissue, leaving the ablated tissue in place.
Ultrasound. Therapeutic ultrasound relies on the fact that as an acoustic wave propagates through tissue, part of it is absorbed and converted to heat. When hot enough, such tissue is thermally coagulated. Focusing sound waves allows concentrated energy deposition to occur deep in tissue, allowing precisely localized heating and thermal coagulation while sparing intervening tissue.
Cryotherapy. Cryotherapy, also called cryosurgery, cryoablation or targeted cryoablation therapy, is a minimally invasive treatment that uses extreme cold to freeze and destroy the target tissue, such as a cancerous tumor. It is usually conducted by an interventional oncologist, interventional radiologist, or, in the case of cardiac applications, by an interventional cardiologist.
Thermal. Several modalities may be employed that indirectly raise local temperature: light, microwave, ultrasound. Considered separately, thermal ablation specifically refers to the direct use of heated fluid or metal for the therapeutic destruction of tissue.
Microwave. Microwave hyperthermia is a non-ionizing form of radiation therapy. Low levels of microwave energy are used to vigorously vibrate water molecules in tissue to quickly and effectively heat the tissue to a physical penetration depth defined by the microwave frequency.
Hydromechanical. Hydromechanical ablation is energy-based tissue destruction accomplished via mechanical means, such as jets of water or saline.
Ablation technologies are used across the spectrum of clinical specialties. The largest share of the market for energy-based ablation devices is used in cancer therapy, primarily using the radiation therapy modality. Following that is general surgery with its use of electrocautery and electrosurgical devices, RF ablation, cryotherapy, etc. Cardiovascular is thought to be third, even though cardiovascular is making the most noise in the medical press with RF and cryoablation of atrial fibrillation, this segment is thought to be third in share order. The remaining applications are relatively small and fall in line behind the three leading sectors.
Below is illustrated the relative share of the ablation technologies market by clinical specialty.
Source: MedMarket Diligence Report #A145: "Ablation Technologies Worldwide Market, 2009-2019: Products, Technologies, Markets, Companies and Opportunities."