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Effects, risks and precautions of tattoo removal using pico laser



If you have a tattoo, it will not disappear naturally. If you want to get rid of the tattoo, you can have a surgical operation with a scalpel or you can remove it with a laser .

Lasers used in cosmetology have different performance depending on the machine, and when used for tattoo removal, there is a risk that some machines may have tattoos of indelible colors or that keloid-like marks may remain after the procedure.

Among the lasers, the pico laser can be expected to be effective in removing tattoos of almost all colors . In addition, it is said that the marks after treatment are less noticeable than other lasers.

Multiple treatments are required to be effective in removing tattoos with a pico laser. By checking the price market, downtime, risks, etc. in advance, you can receive the treatment with peace of mind.

Unlike permanent makeup, tattoos that inject dye into the deep layers of the skin

There are tattoos and permanent makeup as treatments that inject dye under the skin to color the skin. Both treatments are similar, but there are differences in the site and duration of dye injection.

Human skin consists of three layers from the outside: the epidermis layer, the dermis layer, and the subcutaneous tissue. Permanent makeup injects dye into the epidermis layer, and tattoos inject dye into the dermis layer .

In the epidermis layer, skin cells called turnover are reborn, and old skin cells become keratin and peel off from the skin. The dye injected into the epidermis layer with permanent makeup gradually fades due to turnover, so the duration is said to be 1 to 3 years.

On the other hand, tattoos inject dye into the dermis layer, which does not undergo regular skin cell renewal like turnover, so once injected dye does not fade. To remove the tattoo, it is necessary to remove it with a laser corresponding to the dye of the injected dye .

Laser mechanism and features of pico laser

Laser wavelength

A laser is a type of light. Light has the property of a waveform that repeats peaks and valleys, and the length of the waveform from peak to peak (or valley to valley) is called the wavelength. Wavelengths are expressed in units of nanometers (nm), which is one billionth of a meter.

Light has multiple wavelengths, but a laser is extracted by amplifying a specific wavelength from multiple wavelengths.

The shorter the wavelength, the shallower the skin, and the longer the wavelength, the deeper the skin. They are called by names such as "ruby laser" and "Alexandr laser", respectively, depending on the specific wavelength extracted.

Main types of laser wavelength
KTP laser 532nm
Die laser Around 585nm-595nm
Red laser 660nm
Ruby laser 694nm
Alexandrite laser 755nm
Diode laser Around 810nm to 1450nm
Nd: YAG (neodymium yag) laser 1064nm
Er: YAG laser 2940nm
Carbon dioxide laser 10600nm

Irradiation time, which is a characteristic of pico laser

As a general rule, when irradiating a laser in cosmetology, instead of continuously irradiating the laser beam, a method called pulse irradiation is used, in which the laser beam is radiated at intervals as if the button was pressed repeatedly. The irradiation time of one shot when pulse irradiation is performed is called the pulse width, and the shorter the pulse width , the stronger the instantaneous energy for the irradiated substance .

The pulse width is expressed in units such as milliseconds, microseconds, nanoseconds, and picoseconds.

Picoseconds (ps) 1 / 1,000,000,000,000s (1/1 trillion seconds)
Nanoseconds (ns) 1 / 1,000,000,000s (1 billionth of a second)
Microseconds (μs) 1 / 1,000,000s (1 / 1,000,000 second)
Milliseconds (ms) 1 / 1,000s: long pulse

About pulse width

A machine that can irradiate a laser in picoseconds is called a "pico laser". In addition to pico lasers, machines that irradiate lasers in nanoseconds are called "Q-switched lasers," and machines that irradiate lasers in milliseconds are called "long pulse lasers."

The machine name of the laser may be expressed by entering the name of the wavelength and pulse width, such as "long pulse die laser", "Q-switched ruby laser", and "picoa lexandrite laser" so that the wavelength and pulse width can be known. For example, in the case of "pico alexandrite laser", it means a laser with a pulse width of picoseconds and a wavelength of 755 nm.

Mechanism of tattoo removal using pico laser

Photothermal action

When a tattoo is irradiated with a laser, the dye molecules absorb the laser light and generate heat energy, but if the laser is continuously irradiated for a long time, the generated heat energy tries to escape to the surrounding tissues. However, if the laser irradiation time is short, the thermal energy does not escape to the surrounding tissue, and the thermal energy stays in the dye molecules and destroys the molecules . This action is called the photothermal action.

Depending on the material to be irradiated with the laser, the time from absorbing the laser light to releasing the heat energy to the surrounding tissue varies. The time it takes to release heat energy is called the heat relaxation time, and the heat relaxation time of tattoo dyes is said to be 10 picoseconds to 1000 picoseconds (1 nanosecond). Not only pico lasers, but also Q-switched lasers that irradiate lasers in nanoseconds can cause photothermal action on tattoo dye molecules.

It is said that tattoos fade when the dye molecules destroyed by photothermal action evaporate and disappear , or when they are preyed on by macrophages, which are a type of white blood cell, and digested and excreted .

Photoacoustic effect

When thermal energy is applied to the dye molecules with a laser, the molecules undergo thermal expansion and become waves (stress) that diffuse into the surrounding tissue.

However, if the laser irradiation time is extremely short, the stress of thermal expansion cannot diffuse to the surrounding tissue and is trapped in the molecule. The trapped stress becomes high pressure and eventually crushes the molecule . This action is called the photoacoustic action.

Similar to photothermal action, the time (stress relaxation time) from absorption of laser light to letting waves escape to surrounding tissues differs for each substance, and the stress relaxation time of tattoo dyes is 1 nanosecond. It is said to be shorter than a second . Therefore, unlike photothermal action, Q-switched lasers cannot produce photoacoustic action .

Dyes tattoo milled photoacoustic effect, in addition to being well vaporized and disappearance or digested and discharged photothermal effect, tattoos fading result by molecules of the dye is no longer visible to the smaller becomes eyes are milled It has been.

Differences in the effects of pico laser and Q-switched laser in tattoo removal

The Q-switched laser is the machine that exerts only the photothermal effect on the tattoo dye molecules, and the pico laser is the machine that exerts the photoacoustic effect and the photoacoustic effect.

The photothermal action does not have the power to grind the tattoo dye molecules into small pieces until they are invisible. It is said that the Q-switched laser treatment, which leads the tattoo to fade by photothermal action, requires more time and frequency than the pico laser treatment, which has photoacoustic and photoacoustic effects, before the tattoo fades . According to clinical data, there is a difference of about 2 to several times in the time and number of times until fading.

In addition, after the molecules of the tattoo dye are destroyed by the action of light and heat, heat energy is transferred to the surrounding tissues, causing heat damage. It is said that the stronger the degree of thermal damage, the longer the downtime.

Q-switched lasers destroy tattoo dye molecules only by photothermal action, so the degree of heat damage to surrounding tissues is strong and downtime is said to be long.

Pico lasers provide both photothermal and photoacoustic effects on tattoo dye molecules. However, the photoacoustic effect has a greater effect on the tattoo dye molecules, and the photoacoustic effect has a negligible effect. As a result, the degree of thermal damage to surrounding tissue caused by photothermal action is weak and tends to result in shorter downtime than Q-switched laser treatment .

From clinical data, the colors of tattoo dyes that can be expected to fade with a Q-switched laser are black, green, and red, and there is clinical data that colors other than the three colors are slightly lighter or do not change at all. On the other hand, pico lasers may require a long period of time and multiple treatments before they fade depending on the color, but it is said that dyes of almost all colors can be faded .

Tattoo color and pico laser wavelength related to tattoo removal effect

The wavelength of laser light that is easily absorbed differs depending on the color of the tattoo dye. The more the laser light is absorbed, the higher the energy of heat and stress and the stronger the force acting on the dye molecules, so in most cases the treatment is performed by changing the wavelength depending on the color of the tattoo.


Black dye absorbs all wavelengths, and there is almost no difference in absorption rate depending on the wavelength. The longer the wavelength, the deeper the skin, so the wavelength is selected according to how deep the dye is in the skin layer. If the position of the dye is deep, a long wavelength is selected, and if it is shallow, a short wavelength is selected.


Blue dye has a higher absorption rate of laser light in the order of 670nm> 755nm> 785nm> 532nm> 1064nm, and it is said that the higher the absorption rate, the stronger the energy for crushing dye molecules. Since there is no big difference in the absorption rate of wavelengths from 600nm to 800nm, most of the irradiation is performed by selecting one of 670nm, 755nm and 785nm wavelengths by the pico laser machine.


The absorption rate of purple dye is 532nm> 670nm> 755nm> 785nm> 1064nm in descending order. The absorption rate from 500nm to 600nm is extremely high, but the wavelength is selected and irradiated after considering the balance depending on how deep the skin layer is. It is said that wavelengths of 532nm and 670nm are often selected.


The green dye absorbs more laser light in the order of 670nm> 755nm> 785nm> 532nm> 1064nm. Since the absorption rate of wavelengths from 600 nm to 800 nm is higher than that of other wavelengths, it is said that irradiation is often performed by selecting one of 670 nm, 755 nm, and 785 nm.


The red dye has a higher absorption rate in the order of 532nm> 1064nm> 670nm> 755nm> 785nm. Wavelengths from 500 nm to 600 nm have the highest absorptivity, and above 600 nm, the absorptivity becomes extremely low. Therefore, in most cases, the wavelength of 532 nm is selected for irradiation.


The absorption rate of yellow dye increases in the order of 532nm> 670nm> 755nm> 785nm> 1064nm, but above 550nm, the absorption rate becomes 1/4 or less compared to the wavelength of 500nm to 550nm. Therefore, in most cases, the wavelength of 532 nm is selected for irradiation.


The orange dye has the highest absorption rate in the order of 532nm> 670nm> 755nm> 785nm> 1064nm. However, since the absorption rate drops significantly above 550 nm, the wavelength of 532 nm is often selected.

Skin color

The absorption rate of flesh-colored dyes increases in the order of 532nm> 670nm> 785nm> 1064nm. In most cases, the wavelength of 532 nm is selected because the absorption rate from 500 nm to 550 nm is high compared to other wavelengths. However, there is a risk of blackening after irradiation. In most cases, when blackened, irradiation is performed by selecting a wavelength of 1064 nm.


Since the absorption rate of white dye is low at all wavelengths, the energy at which the dye molecules are crushed is low, and it is said that it is difficult to remove unless the number of irradiations is increased compared to other colors. In addition, there is a risk of discoloration to other colors such as blackening, and if the color changes, it is necessary to change the irradiation wavelength depending on the color.

Those who are suitable for tattoo removal using a pico laser

  • Those who want to erase a wide range of tattoos
  • Those who want to gradually erase the tattoo
  • Those who can go to the hospital
  • Those who do not want to leave an incision mark

Frequency and frequency of tattoo removal using pico laser

Studies have shown that the fading of the dye often becomes apparent about 2 months after the pico laser irradiation, so treatment is recommended about 2 to 3 months after one irradiation. ..

If you want to make the pico laser irradiation interval as short as possible, in principle, you can perform the procedure with an interval of about 4 weeks.

The recommended number of treatments depends on the color and size of the tattoo and the area where the tattoo is placed .

The recommended frequency and frequency of tattoo removal varies from person to person, so please consult your doctor for details.

Price of tattoo removal using pico laser

For tattoo removal using a pico laser, the market price is 2,000 to 7,000 yen per 1 ㎠ (square centimeter) .

The larger the treatment area, the lower the price per ㎠. Many medical institutions set prices every 5 ㎠ instead of every 1 ㎠, such as 1 ㎠ to 5 ㎠ and 5 ㎠ to 10 ㎠.

Also, if the tattoo is multicolored, the fee may be higher at some medical institutions, so it may differ from the fee posted on the website. If you want to remove multicolored tattoos, please check with your medical institution in advance.

Pain and downtime for tattoo removal with pico laser

Tattoo removal pain

It is painful to use a pico laser to remove tattoos, so as a general rule, anesthetize before performing the procedure .

In many cases, anesthesia cream, laughing anesthesia, or local anesthesia is used, but depending on the medical institution, general anesthesia can be performed if desired.

Depending on the medical institution, some anesthesia methods may not be available, so please check with your medical institution in advance for available anesthesia .

Tattoo removal downtime

After the treatment, exudate, which is a body fluid that oozes from the surface of the wound, may come out from the part that has undergone tattoo removal, or scabs may form . Exudate contains plasma, white blood cells, proteolytic enzymes, and cell growth factors, which are components that repair wounds and help cells grow.

If exudate or scabs form from the treatment site, apply an ointment prescribed by a medical institution or cover with gauze.

Symptoms such as exudate and scabs are said to subside within about two weeks after the procedure, but downtime varies from person to person depending on the size, color, and site of the tattoo.

Precautions after tattoo removal using pico laser

  • Do not irritate (rub, scratch, etc.) the treated area
  • Do not forcibly remove the scab
  • Take proper measures against UV rays (sunburn measures)
  • If your skin is dry, moisturize it well.
  • Avoid exercise and saunas that improve blood circulation

Risks and side effects of tattoo removal with pico laser

  • Redness, swelling, and pain may occur at the treatment site, but it can be treated with medicine prescribed by a medical institution. Blisters may form, but improvement can be expected by draining the contents.
  • Bleeding may occur, but in most cases it is said to subside within a few days to a week. If bleeding continues, please consult a medical institution.
  • The treatment area may be pigmented, but it will subside over time. If you want to cure early, use internal medicine or topical medicine.
  • Depigmentation and scarring may occur, but improvement can be achieved with a fractional laser that irradiates the laser light in dots.
  • The tattoo dye may turn black, but it is said that the color will fade after multiple pico laser treatments.
  • If there are wounds such as keloid-like wounds on the skin when tattooing, the wounds that were not noticeable with the tattoo dye may be noticeable due to the dye fading.

Those who cannot receive pico laser treatment

  • Pregnant / lactating
  • Those with photosensitivity
  • Those with keloid constitution

If you have any other illness or are uneasy about your physical condition, please consult a medical institution.

Tattoo removal methods other than pico laser

If you want to remove the tattoo with something other than a pico laser, you will need surgery with a scalpel.

How to scrape the skin to the dyed part of the tattoo

It is an operation to scrape the skin up to the part where the tattoo dye is, and it is called dermabrasion (sakuhijutsu).

After scraping the skin, it waits for the skin to regenerate due to the "natural healing power" that is inherent in the human body and is the ability to heal wounds and injuries by itself.

It is said that the scars of surgery are often noticeable because the skin is scraped off.

Those who are facing

  • Those who want to erase a wide range of tattoos
  • Those who want to erase a wide range of tattoos at low cost

How to cut the tattoo part

It is an operation to remove the tattoo part and sew the skin together, which is called excision surgery.

Since the tattoo part is cut off, the tattoo will surely disappear. However, since it is necessary to sew the skin after excision, as a general rule, surgery is performed on a small tattoo.

Depending on the condition of the skin, a large tattoo may be removed exceptionally, but in that case, surgery is performed in multiple steps.

Those who are facing

  • Those who want to quickly erase small tattoos
  • Those who have difficulty going to the hospital many times

How to transplant skin

There is surgery to remove the tattoo and transplant the skin from other parts such as the buttocks . It is called skin grafting and is often performed on relatively large tattoos.

Unlike dermabrasion and excision, scars remain not only on the tattoo area but also on the area where the skin was collected.

Those who are facing

  • Those who want to erase large tattoos less often
  • Those who want to erase tattoos quickly

How to choose a medical institution to receive tattoo removal with a pico laser

The tattoo removal treatment using the pico laser is a treatment with stronger laser energy (output) than the pico laser treatment aimed at rejuvenating the skin such as spots, wrinkles, and acne scars.

If the output of the pico laser is too strong, it will cause more damage to the skin and increase the risk of pigmentation and scarring. To reduce the risk, it is necessary to fine-tune the wavelength and output while checking the condition of the tattoo after irradiation.

It seems that some medical institutions perform the treatment by a nurse, but a doctor's treatment is required to perform the treatment while checking the condition of the tattoo .

In addition, pain, swelling, and blisters may occur after tattoo removal. Before the procedure, it is safe to check what to do if a problem occurs and select a medical institution that is convinced of the response .