What Is LinearZ? How Linear HIFU Differs from Ultherapy

LinearZ is a HIFU (high-intensity focused ultrasound) lifting device: it concentrates ultrasound at a single point inside the skin to create heat. Every HIFU device works on this same principle, Ultherapy included. What differs from one device to the next is how deep the focal point sits and how the points are laid out. LinearZ links its focal points into lines, leaving thermal coagulation points evenly across a wide area, and its 4.5 mm, 3.0 mm and 1.5 mm cartridges treat the SMAS fascial layer, the fat layer above it and the dermis separately.

What is LinearZ?

LinearZ is a HIFU lifting device made by Jeisys Medical. It is a non-surgical option to consider if you are bothered by facial sagging or loss of firmness, a loosening jawline, or fat under the chin.

Treatment is counted in shots. We choose between 500, 700 and 1,000 shots based on your facial structure, how much sagging there is and the area being treated. Depending on the number of shots, a session takes about 10–20 minutes.

How does HIFU work under the skin?

HIFU gathers ultrasound energy at one point inside the skin. The temperature at that point rises to 60–70°C, creating a small thermal coagulation point. Because the focus forms below the surface, the epidermis and the tissue in between are relatively spared, and the heat stays mainly at that spot.

The heat usually does two things.

First, the heat at the focal point makes existing collagen contract, so many people feel a tightening right after treatment. Then, as new collagen and elastin form around the coagulation points, firmness and contour can keep improving gradually over 2–3 months. How much they improve varies from person to person.

Why does LinearZ link its focal points in lines?

When focal points are placed as dots, the energy gathers at each separate point. LinearZ joins its focal points into a line as it fires, so the thermal coagulation points are left evenly across a wide area. LinearZ can also fire in dots, but we rarely use that mode; we switch cartridges to suit the area and the goal, and treat in lines.

Where the fat layer is thick, such as the jawline or a double chin, this heat can also reduce some of the fat, which can help lift sagging and reduce fullness at the same time. In areas where losing volume can make the face look hollow, such as the sides of the cheeks, we do not concentrate the energy.

Is LinearZ the same as Ultherapy?

The principle is the same. Both are HIFU devices that gather ultrasound at a point to create heat. One difference is how the focal points are laid out: Ultherapy places them as dots, while LinearZ links them in lines.

We have both devices at our clinic, so which one suits you is something we decide together at consultation, based on how much sagging there is, the area and your skin condition.

How are LinearZ cartridge depths chosen?

Each LinearZ cartridge focuses at a different depth, and each depth works on a different layer.

We usually use 4.5 mm and 3.0 mm, and mainly 4.5 mm on the jawline and double chin, where the fat layer is thick. Exactly which depths to use, and how many shots at each, is decided while we assess your facial structure and degree of sagging.

How is LinearZ different from Sofwave and XERF?

All three are often grouped together as "lifting", but they use different energy and reach different layers.

The three devices play different roles. When sagging and loss of firmness come together, many people have LinearZ and XERF on the same day; in that case LinearZ goes first and XERF follows. LinearZ works on the deeper layers, XERF on the firmness of the skin as a whole.

When might LinearZ not be the right choice?

If your face is on the thin side, or your cheeks have looked hollow after a previous lifting treatment, Sofwave, which does not reach the fat layer, may be worth considering first. If what we see is mainly lost volume or the quality of the skin itself rather than sagging, we will tell you so at consultation and look at other options with you.

Before treatment, let us know if any of these apply:

• Inflammation or infection in the area to be treated: we wait until it has settled.
• A tendency to form keloids: please tell us beforehand.
• Pregnancy: we generally do not recommend treatment.

Metal or implants in the body do not affect LinearZ treatment.

When do LinearZ results show, and how long do they last?

You may feel some tightening right after treatment, and lift and firmness can improve further over the next 2–3 months as collagen builds. Results last about 3–6 months, varying with your skin condition and lifestyle.

That is why we recommend starting with about three sessions, 2–3 months apart, followed by maintenance about once every six months.

What is recovery like after LinearZ?

Temporary redness, warmth or mild swelling can follow treatment. The redness mostly settles within the day, so daily activities and makeup are fine the same day.

Occasionally the treated area feels tender when pressed, or a faint bruise appears. Rarely, nerve irritation leaves a tingling feeling, which usually resolves within a few weeks.

In summary

HIFU creates heat by focusing ultrasound at a point, and LinearZ links those focal points into lines so they are left evenly across a wide area. The 4.5 mm cartridge mainly works on the SMAS and the 3.0 mm on the fat layer beneath the dermis, and on a jawline with a thick fat layer, LinearZ can also help reduce some of the fullness. If your face is thin or you are worried about hollow cheeks, a different device may suit you better, so we decide which depths to use and how many shots after examining your face in person.

→ More about LinearZ · More about XERF · More about Sofwave