FAQ

We have compiled a range of answers to the most common question about HIFU and the technology around our products. Please click on the arrow to open  the answer.

If you have other questions or comments to this section, please let us know, so we can add, amend or correct this as soon as possible.

The mechanism used in HIFU is similar to using a magnifying glass to focus light. Instead of concentrating light, HIFU however uses a focused acoustic transducer to concentrate a beam of ultrasound waves onto a specific target.

In contrast to light-beams, the ultrasound can however pass through tissue with little effect. When the ultrasound reaches the focal zone, where the beam converges, the energy is greatly intensified, and thereby induces thermal and mechanical effects. The method can therefore be used as a non-invasive way to treat diseases and features inside the human body without any form of surgical procedures or puncture of the skin surface.

The HIFU method is very well suited to make localized therapeutic zones of well-defined volumes inside the human body. After treatment, the body’s own immune system is immediately activated and starts a process of removal of dead and damaged cells via the lymphatic and vascular systems. Since the procedure does not involve any surgery or other open exposure of the body’s internal structures, the risk of infections, scarring and other adverse effects typically seen in traditional surgery is significantly reduced.

The HIFU functionality can therefore be summarized as follows:

    • Ultrasound is focused into a small focal zone with very high acoustic energy density
    • The focal zone is created non-invasively inside the body without surgical procedures
    • The very high energy-density in the focal zone creates a biological response
    • There is no biological effect from the HIFU in the adjacent tissue outside the focal zone
    • The local heating and mechanical forces in the focal zone kill or activate cells and disrupts connecting tissue
    • The body’s immune system is activated to repair and renew damaged cells and tissue

See furhter explanations and animations here.

Focused ultrasound is an early-stage, noninvasive therapeutic technology with the potential to improve the lives of millions of patients with a variety of serious medical disorders.

It offers a disruptive, game-changing alternative or complement to surgery, radiation therapy, drug delivery, and cancer immunotherapy. This revolutionary technology has the potential to increase the quality and longevity of life and decrease the cost of care by transforming the treatment of a broad range of indications.

Today, HIFU treatments of e.g. Parkinsons related tremor, glioblastoma, uterine fibroids, liver cancer, pancreatic cancer, bone metastases and many more are seeing groundbreaking results.

In TOOsonix we have brought the same revolutionary results to the largest organ of the human body: The skin.

The high frequency HIFU commercialized by TOOsonix is the first to enable true dermatological HIFU treatments that are confined and accurately dosed in the human epidermis and dermis without affecting deeper layers.

The TOOsonix HIFU treatment has demonstrated high clinical efficacy compared to the relevant alternatives for each of its intended indications. At the same time it is a very gentle therapeutic modality with very few and mild side effects.

In addition to comparable or superior efficacy, patients and clinicians thus experience a range of other advantages compared to other conventional methods:

    • No radiation
    • No surgery
    • No fumes or smells
    • No need for anesthesia
    • No down-time after treatment
    • Minimal risk of scarring
    • Minimal risk of dyspigmentation

Different modes of HIFU treatment can be performed depending on the HIFU frequency and energy settings of the device, ranging from deep direct ablation and necrosis of cells in the focal zone due to local thermal heating and mechanical forces, to modifications in pharmaceutical transport and uptake due to mild local hyperthermia.

Various HIFU devices are commercially available for medical, aesthetics, and fundamental research from a number of suppliers world-wide. The available devices however typically operate at relatively low frequencies, and therefore produce focal zones with dimensions in the mid-millimeter to low centimeter range.

This is obviously not optimal in cases where the clinician wants to target very small features and treat with very high precision as it is necessary for dermatological therapy. To overcome these problems, TOOsonix has developed and commercialized a high-frequency HIFU technology operating at significantly higher frequencies than the approximately 0.5 to 10 MHz available from existing suppliers in the market.

The higher frequency offered by the TOOsonix systems (20 MHz) allows for the ultrasound to be focused into much smaller focal zones within a target than ever before.

The inverse relation between frequency and size of the focal zone can for example be illustrated by a schematic HIFU treatment in the human skin. The figure below illustrates the approximate relative size of lesions made with HIFU devices operating at different frequencies in relation to the size of human skin. It can clearly be seen that low-frequency HIFU devices creates very large lesions, which are not nearly accurate enough to target small features in the human skin or e.g. small animal models. Only TOOsonix System ONE, operating at 20 MHz is capable to make sufficiently accurate focal zones that can be confined to the epidermis and dermis without damaging deeper tissue.

Handpieces from TOOsonix are based on a so-called single element transducer technology. This means that each dose from the system produces a small and highly accurate single focal zone at a pre-determined fixed depth.

The handpieces from TOOsonix are characterized by their nominal focal depth (NFD), depicting the distance from the skin surface to the geometrical focal point, which is also the maximum therapeutic depth.

System ONE can be supplied with four different color-coded handpiece variants:

    • NFD 0.8 mm (green) for very superficial lesions in or close to epidermis
    • NFD 1.3 mm (blue) for lesions in epidermis and upper dermis
    • NFD 1.8 mm (white) for lesions in mid-dermis
    • NDF 2.3 mm (yellow) for lesions in deep dermis

See animations superficial (ablative) and mid-dermis (non-ablative) treatments here.

Handpieces from TOOsonix are based on a so-called single element transducer technology. This means that each dose from the system produces a small and highly accurate single focal zone at a pre-determined fixed depth.

To treat a skin disease or condition covering even a very small area, several doses are needed to cover the target. This can be done either by manual activations of the doses in “Single Shot Mode” or by selecting an automatic repetition of the doses in “Repeated Shot Mode”.

The software shows a real-time video feed of the treatment area, and the operator can easily follow the treatment progress, while covering the desired treatment area. The treatment can typically be further assisted by outlining relevant target areas and margins by simple color marking on the skin before treatment is started.

By covering areas with closely positioned treatment dosing, a network of coagulated tissue with dead cells and disrupted connective tissue can be obtained. Dependent on the target location, the practitioner can select the handpiece with the appropriate focal depth (NFD).

For superficial treatment of e.g. BCC, actinic keratosis or pigmentary disorders, handpieces with NFD 0.8 or 1.3 mm are typically chosen (referred to as “Ablative treatment”). Treatment with these disrupt the upper skin barrier, and the response to treatment is therefore a gradually formation of a thin wound crust over a few days after treatment. This crust heals over a few weeks after healthy skin has been regenerated below.

For deeper diseases and conditions (“referred to as “Non-ablative Treatment), such as cutaneous neurofibroma and other skin tumors, handpieces with NFD 1.8 or 2.3 mm are needed. These treatments do not necessarily damage the upper skin barrier, and transport of damaged cells and tissue is thus performed by the vasculature without visible signs on the surface.

See animations of the ablative and non-ablative treatments here.

The size of a HIFU treatment zone is first and foremost dependent on the wavelength of the ultrasound signal from the system.

The wavelength of ultrasound varies inversely with frequency, i.e. the higher the frequency, the shorter the wavelength. A short wavelength will in turn generate a smaller focal zone.

The intensity of the ultrasound signal naturally also plays a significant role for the size and shape of the zone experiencing biological effects from the HIFU energy. At high energy levels, the intensity of the ultrasound can be enough to initiate high temperatures as well as cavitation and high shear forces inside the focal zone. In this case, the focal zone and its immediate surroundings will show signs of both physical and thermal biological effects, for example destruction and disintegration of connective tissue and immediate cell necrosis. At lower energy levels, the treatment zone is subjected primarily to thermal effects, where tissue is coagulated through more gentle heating that affects only cells and very soft tissue.

The shape and size of the treatment zones are logically both time- and energy-dependent. The various mechanical and thermal effects increase the volume of the thermal point over time and with increasing energy levels. Simple heat conduction will for example conduct heat to adjacent volumes, and thereby gradually increase the zone experiencing biological effects over time.

It should be noted that coagulated tissue will have both different acoustic and thermal properties than the original tissue. In practice, lesions therefore mostly expand and grow from their original depth towards the source of the ultrasound as illustrated in the below figure.

Using common settings in human treatments with TOOsonix System ONE-M, the zone of biological effect is approximating a triangular/ellipsoidal shape that is approximately 1.0-1.5 mm “deep” and 0.75 mm as its maximum diameter.

See a video-sequence of how the focal zone develops over time here.

The handpieces supplied for TOOsonix System ONE are characterized by their nominal focal depth (NFD), depicting the distance from the skin surface to the geometrical focal point, which is also the maximum therapeutic depth.

System ONE can be supplied with four different color-coded handpiece variants:

    • NFD 0.8 mm (green) for very superficial lesions in or close to epidermis
    • NFD 1.3 mm (blue) for lesions in epidermis and upper dermis
    • NFD 1.8 mm (white) for lesions in mid-dermis
    • NDF 2.3 mm (yellow) for lesions in deep dermis

See animations of ablative and non-ablative treatments here.

A treatment with TOOsonix System ONE involves repetitive dosing to fully cover a target area including an appropriate treatment margin. The handpiece is moved manually on the skin surface and dosing is administered via the system footswitch. During treatment the practitioner can follow treatment progress and response directly in real-time on the user interface showing a microscope video-feed of the skin being treated.

Typically, dosing can be repeated every 1-2 second, thus making effective treatment very fast and efficient. The below table shows an overview of effective doses needed for different sized lesion (including treatment margins). Treatment of e.g. BCC and AK, where high efficacy is of primary concern, a dense dose coverage is typically chosen by the practitioner. In other cases where the aesthetic result is of primary concern, using a more moderate dose coverage is typical. This is for example relevant for e.g. vascular or pigmentary lesions.

Most smaller lesions can thus be completed in les than 1 minute of effective treatment time.

See an example of a clinical treatment here.

The TOOsonix treatment leads to momentary pain that is often described as small needle injections. The pain is however only present during the HIFU dosing itself.

The treatment is therefore generally well-tolerated by most people. On a pain scale of 0 to 10, most patients score 2 to 5, while similar scoring for laser, cryosurgery and photodynamic therapy is significantly higher. However, pain is experienced differently, and will always be dependent on treatment location due to the difference in sensory nerve density.

For superficial treatments (handpieces NFD 0.8 and 1.3 mm), regular anesthetic cream applied 60 minutes before treatment is very effective and can usually prevent most pain. For deeper treatments (handpieces NFD 1.8 and 2.3 mm), the penetration of the anesthetic cream is low, and the effect is therefore similarly lower. In rare cases, where treatments are carried out on pain-sensitive patients or locations, local intralesional anesthetics can be used to fully eliminate pain during treatment.

The direct effects following a TOOsonix treatment is normally very mild without down-time for the patient.

The treated area should be cleaned to remove the gel, and a temporary dressing can be used in cases where a large area has been treated or the treatment site is subjected to external forces. However, even if the basement membrane is disrupted during treatment, bleeding or other liquid discharge is uncommon.

In the days and weeks after treatment, patients are simply recommended to maintain good hygienic practice, and preferably apply moisturizing creams on the treatment areas to prevent dryness, fissuring and cracking of the thin wound crust that may form on the treated surface.

The response to treatment can be differentiated into two main groups, primarily depending on the handpiece selection.

Upper dermis treatments (referred to as an “Ablative Treatment”):

Handpieces with NFD 0.8 or 1.3 mm are preferable for treatments requiring cell necrotization and tissue denaturation of a target in the epidermis or upper half of the dermis. This leads to subsequent replacement of damaged tissue with healthy cells and tissue through creation of a superficial crust during the healing phase. The crust will typically release spontaneously after approximately 2 weeks. A typical response to a superficial treatment is shown in the below figure with a schematic comparison containing the main phases of healing.

Mid-and lower dermis treatments (referred to as “Nonablative Treatment”):

Handpieces with NFD 1.8 or 2.3 mm are preferred for treatment targets located in the mid- and deeper dermis. With moderate energy settings and coverage, these handpieces offer a treatment response with internal transport of damaged cells and tissue through the lymphatic and vascular systems without necessarily creating superficial erosions and crusts on the surface. Treatments are thus truly non-invasive and thereby with very low risk of visible post treatment complications such as dyspigmentation or scarring. However, if energy levels are too high or dose-coverage too dense, the resulting erosion will by nature be deep, and thus lead to longer wound healing and risks for scarring and dyspigmentation.

See animations of ablative and non-ablative treatments here.

HIFU Energy

The TOOsonix system converts electrical energy from the power grid to an acoustic ultrasound signal emitted from the ultrasound transducer in the handpiece.

Each handpiece has a calibration curve encoded into its control unit, which calculates and regulates the necessary power settings to obtain a certain selected acoustic energy delivery. The acoustic output energy delivered from the TOOsonix handpiece is linked directly to the selected combination of power and shot duration in the operational menu.

The relation between shot duration, energy level and power level are easily calculated from the below simple formula:

Output energy [J] = Shot duration [s] x Power [W]

The software will use this formula to continuously update the calculated acoustic energy when the shot duration or power level is changed.

Each handpiece is furthermore protected from energy settings that is potentially damaging for the components inside. The handpiece therefore has a pre-defined allowable combinational range between shot duration and power. Please note that the allowable range depends on the type of handpieces and can be different for different types.


Duty Cycle and Shot Interval

The systems from TOOsonix also offer an option for automatic shot repetition at fixed intervals when “Repeated Shot Mode” is selected. The shots are then automatically repeated at fixed intervals that can be adjusted by the user from the operational menu.

The Shot Duration and Shot Interval determines the sonification session Duty Cycle (the percentage of time in which the system actively transmits ultrasound signals).

The TOOsonix systems have been limited to certain minimum intervals in relation to the burst time. Each handpiece has limitations encoded into its control unit to prevent damaging components and potential overheating or degradation. These limitations means that the higher the energy the system operates at, the longer the interval between bursts has to be.

Adjustment of the required Dose Interval is done from the operational menu. The software will use the selection to continuously update the calculated Duty Cycle when the Shot Interval or Shot Duration is changed.

The TOOsonix system converts electrical energy from the power grid to the final acoustic ultrasound signal emitted from the ultrasound transducer in the handpiece.

The system uses an internal calibration curve encoded into each handpiece during the factory calibration. The calibration curve is based on specialized measurements which calculate and regulate how much electrical power is needed to produce the acoustic energy chosen in the operational menu.

As with any other high power ultrasound transducers, the components generating the ultrasound in the TOOsonix handpiece is however subject to some degradation with use. The calibration therefore gradually becomes inaccurate, and the actual energy emitted from the handpiece might become lower than what the setting in the software indicates.

The main driver for transducer degradation is the total accumulated emitted energy. The software therefore includes an “energy credit counter”, which gives a clear indication of the energy emission left in the handpiece.

After expiration of the energy amount in the handpiece it will be blocked for further operation, and a new valid handpiece has to be connected to continue any operation.

We recommend that expired handpieces are disposed as electronic waste materials at approved sites. Alternatively, handpieces can always be returned to TOOsonix for safe disposal.

The TOOsonix systems are all Made in Denmark and carries the “Country of Origin Denmark” on all relevant documentation.

The company, its founders, and its investors, are based in Denmark. The company is located in the DTU Science Park, a leading hub for MedTech, Biotech and pharmaceutical companies, and directly linked to one of the world’s leading universities in science and technology.

The design of the TOOsonix systems is inspired by the Danish design principle of clean functionality and simplicity. Inside the unit, we have mimicked another of Denmark’s great success stories of modular systems from Lego.

The TOOsonix systems are designed from a completely modular principle, where individual modules can be assembled, maintained or replaced in very short time.

Down-time should therefore be minimal. Should the equipment break down, a quick service visit will get you up and running again in short time after simply replacing the problematic module.

The HIFU systems from TOOsonix, regardless of if they are for human treatments or laboratory research, consist of the base structures enabling HIFU treatments (or experiments) directly after delivery and training of relevant users. The system includes the following units and functions:

    • Fully functional System ONE.
      • Options for human medical or research use.
      • Options for appropriate electrical power input in region of delivery
    • Handpieces with integrated microscope camera and options for four different color-coded Nominal Focal Depths (NFD):
      • NFD 0.8 mm (green) for very superficial lesions in or close to epidermis.
      • NFD 1.3 mm (blue) for lesions in epidermis and upper dermis.
      • NFD 1.8 mm (white) for lesions in mid-dermis.
      • NDF 2.3 mm (yellow) for lesions in deep dermis.
    • Supporting materials to facilitate operation of the system.
      • Acoustic window films for covering handpiece head.
      • Collars to fixate film on handpiece head.
      • Ultrasound Tester.
      • Ultrasound Gel.
      • DI Water for transducer filling.
      • Syringe for water transducer filling.

We welcome that any other special research-requests are discussed with our engineering department.

The company policy is that customers should only be satisfied if they have been fully and effectively supported through the entire process from the first inquiry to the final handover of a system to trained and qualified users.

A satisfied customer that has been enabled with an operational system according to their specifications will in turn enable TOOsonix in obtaining our overall mission:

Create better lives with high frequency ultrasound therapy.


The TOOsonix systems are CE marked and certified for safe operation as per the harmonized pan-European standards. The systems are therefore marketed in the 28 EU member states plus Switzerland, Norway, Turkey, Iceland, and Liechtenstein.

The systems can be provided either as a full purchase or on a rental agreement with a fixed commitment for the rental term.

The TOOsonix systems are provided via direct sales from the main office of the company in Denmark. This is done because it is normal that a sales process includes highly technical discussions regarding customer-specific solutions and settings. By keeping the communication direct and concentrated, we can obtain the fastest and best possible result for the customer.

We feel that customers should only be satisfied if they have been fully and effectively supported through the entire process from the first inquiry to the final handover of a system to trained and qualified users.

A satisfied customer that has been enabled with an operational system according to their specifications will in turn enable TOOsonix in obtaining our overall mission:

Create better lives with high frequency ultrasound therapy.

A sales process typically includes the following elements:

    • Review of the standard system, its function, and its contents
    • Discussion and specification of relevant handpieces
    • Discussion of special requirements regarding operational range and settings
    • Selection of commercial model
    • Agree delivery time and shipment
    • Agree installation date
    • Agree training participants and schedule
    • Agree price and payment terms