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Hyaluronic acid preparation An injection method that avoids the risk of Kaisense and enhances pat...




Hidemasa Shinohara
Dr. Hidemasa Shinohara

Skin Refine Clinic Ginza

Regular member of the Japanese Society of Plastic Surgery Certified specialist Regular member of the Japanese Society of Clinical Dermatology Regular member of the Japanese Society of Cranial Forehead Surgery

Medical institution with Dr. Hidekatsu Shinohara

Skin refine clinic Skin Refine Clinic Ginza
Contact: 0120-661-062

Hyaluronic acid preparation An injection method that avoids the risk of Kaisense and enhances patient satisfaction

Hyaluronic acid injection therapy is a treatment that makes changes due to sagging such as nasolabial folds and marionette lines caused by aging inconspicuous, and injects them into the forehead, chin, nose, lips, etc. to adjust the contour and shape.

Hyaluronic acid infusion therapy can solve various problems, but the reason is that it continues to evolve due to repeated research on formulations and injection methods.

KYSENSE® is a hyaluronic acid preparation launched in the EU in February 2021. Kaisense is a hyaluronic acid preparation that is highly safe and can be expected to lift up naturally.

In order to achieve the ideal therapeutic effect while avoiding complications and troubles in hyaluronic acid injection therapy, it is necessary to have a good understanding of the characteristics of the drug and to select an injection method suitable for Kaisense .

We will explain the characteristics of Kaisense as well as the method of avoiding complications and risks in general hyaluronic acid injection therapy, as well as the injection method for increasing patient satisfaction.

How to avoid complications and troubles of hyaluronic acid injection

Hyaluronic acid injection therapy, which is in high demand in aesthetic medicine, has a risk of complications. However, it is often minimized by gaining knowledge.

Informed consent is important for the practitioner to explain possible complications before the procedure and to give consent and consent in order to prevent troubles with the patient .

It is necessary to build trust with patients by providing sufficient information including risks as well as the benefits of the treatment. This increases the likelihood that any complications should be dealt with promptly and appropriately.

Mild to moderate complications of hyaluronic acid injection therapy

Internal bleeding / erythema

Internal bleeding may occur due to damage to minute capillaries with a needle, or erythema may occur as a defense reaction of the living body due to the stimulation of injection of a drug or needle.

Internal bleeding is a frequent complication that appears the day after injection or a few days later and disappears within 2 to 3 weeks. The red to black blood clots in the subcutaneous fat layer look purple when viewed through a filter called skin. After that, it turns yellowish over time.

Cooling after injection is effective for erythema, and it usually subsides in 2 to 3 days.

Internal bleeding and erythema are basically follow-up , but if there is redness, swelling, warmth, pain, or tenderness, there is a suspicion of an infection . In that case, treat with antibacterial drugs.

Please note that the risk of infection increases as the number of needle sticks increases .

Edema / swelling

Immediately after injection, mild edema often occurs about 2 to 3 days after injection due to a biological reaction caused by injection stimulation or foreign matter entering the living body.

The infused hyaluronic acid may swell with water in the body, temporarily becoming edema. Therefore, the point is to inject a small amount so as not to cause excessive correction .

In addition, allergic-like symptoms may occur, such as swelling several days after injection and swelling in areas not injected. In this case, it is necessary to treat with oral allergies or intravenous drip instead of dissolving hyaluronic acid.

Reinjection should be considered after at least 2 weeks if necessary.

Internal bleeding and edema are complications that can occur frequently with any hyaluronic acid preparation, regardless of the practitioner, so informed consent is important to prevent problems with patients.

Delayed allergic reaction / foreign body granuloma

Delayed allergic reactions may include redness, induration, and nodular changes more than a few months after the procedure, and sometimes more than a year later.

Foreign body granulomas are lumps caused by chronic inflammation caused by foreign bodies and are more likely to occur when injected into the dermis layer of the skin .

If a delayed allergic reaction or foreign body granuloma occurs, it may heal spontaneously, but most remain for a long time. If there is no problem in appearance, the course may be monitored as it is, but if there are irregularities in appearance, it is realistic to treat with local injection of steroid or injection of hyaluronidase that dissolves hyaluronic acid. is. If there is no improvement, consider excision.

Tyndall phenomenon, unnatural unevenness

The Tyndall phenomenon, unnatural unevenness, is likely to occur around the orbit where the skin is thin , and although it is affected by the nature of the hyaluronic acid preparation, it is often a complication that is thought to be injected into the surface or shallow part of the skin .

The Tyndall phenomenon is a condition in which hyaluronic acid particles under the skin scatter light and appear pale. In addition, unnatural unevenness is caused by the swelling of hyaluronic acid due to the movement of the orbicularis oculi muscle around the eyes when making facial expressions.

To briefly explain the anatomy of the face, it is a layered structure like Millefeuille, where the skull is covered with muscles, the subcutaneous fat layer is on top, and the surface is covered with skin. Some places are even more complicated.

After understanding such an anatomical structure and appropriately deciding whether to hit the upper or lower layer of the orbicularis oculi muscle, it is highly possible that it can be prevented by using a very small injection amount. Become.

Severe complications of hyaluronic acid injection therapy

Severe complications are more likely to occur due to erroneous infusion into blood vessels due to lack of understanding of facial vascular travel, or compression of blood vessels due to overinjection.

Doctors with anatomical knowledge and extensive practical experience are less likely to mis-inject or over-inject .

If you accidentally inject it into a blood vessel, you need to give a hyaluronic acid dissolving injection (hyaluronidase) promptly.

It 's a good idea to have a hyaluronidase ready just in case . The quicker response to complications is to minimize damage.

Skin circulation disorder / skin necrosis

Skin circulation disorder / skin necrosis is one of the causes of blood circulation disorder.

The main reason for necrosis is thought to be the direct blockage of blood flow by intravascular injection or the indirect blockage of blood flow by compression of the blood vessel by injection around the blood vessel. The midline, which is basically the center of the body, is an anatomically rough area where blood flow is likely to occur.

If you complain of sudden severe pain at the time of injection or if the injection site becomes pale, suspect a vascular embolism .

After injection, it is generally accompanied by dull pain even in the normal course. The pain usually improves day by day in 1 to 3 days, but caution should be exercised if the pain persists or worsens.

Internal bleeding is a common complication, but if it changes from purple to black instead of yellowish, it is suspected to be a blood circulation disorder rather than internal bleeding . However, it is difficult to make a self-judgment about the color tone of this skin, and the presence or absence of pain is important.

If skin circulation disorder is suspected, hyaluronidase should be infused as soon as possible .

cerebral infarction

Although there are few cases of cerebral infarction caused by injection of hyaluronic acid, cases of cerebral infarction after injection into the glabellar area have been reported.

Higher pressure than arterial pressure in the supraclavicular artery, nasal dorsal artery, horny artery, and supraclavicular artery. When hyaluronic acid is injected and reaches the internal carotid artery from the ocular artery, it is thought that hyaluronic acid enters the skull and causes cerebral infarction.

To prevent cerebral infarction, it is important to inject hyaluronic acid slowly and at low pressure .

If cerebral infarction is suspected, it is necessary to promptly transport the patient to a facility with a cranial nerve specialist and explain the injection and treatment details .


Blindness is a serious complication of hyaluronic acid infusion therapy.

Symptoms include severe eye pain, visual impairment / visual impairment, headache, and vomiting, and the skin around the eyes and between the eyebrows is often pale or accompanied by internal bleeding.

Although the cause of blindness has not been completely elucidated, it is thought that hyaluronic acid is sprayed by misinjection into the arteries, obstructing blood vessels, and lacking blood to the retina, leading to blindness.

As a life-saving measure , injection of hyaluronidase, which dissolves hyaluronic acid, which causes vascular embolism, is effective . It has been reported that a quick response may provide relief .

How to choose hyaluronic acid preparation to prevent allergies and rejection

Delayed inflammatory reaction is a problem that has been alerted to hyaluronic acid injection in recent years.

A delayed inflammatory response is defined as an inflammatory response or induration with an inflammatory response that appears at the injection site weeks to months after the injection of hyaluronic acid .

Unlike infectious diseases, there are cases where it occurs only in a part of the injection site, and there are cases where it occurs in the part that has not been injected. The incidence is low, but it can recur and take months to heal.

The cause of the delayed inflammatory reaction is not clearly known, but it is thought that cross-linking agents, bacterial involvement, and antibodies against hyaluronic acid are considered.

It is thought that the cross-linking agent leaks out in the process of decomposing hyaluronic acid, and that macrophage-related inflammation occurs against proteins that are metabolites of bacteria.

It is known that the incidence of delayed inflammatory reaction varies depending on the hyaluronic acid preparation .

In other words, choosing a hyaluronic acid preparation that has a low incidence of delayed inflammatory reactions increases the chances of avoiding trouble .

Small molecule hyaluronic acid that is likely to cause an inflammatory reaction

High molecular weight hyaluronic acid is hyaluronic acid with a long molecular structure in which multiple chains are gathered and connected. Natural hyaluronic acid, such as fluffy fins, chicken combs, and hyaluronic acid that exists in the human body, is high molecular weight hyaluronic acid.

On the other hand, hyaluronic acid artificially made with a small molecular weight is called low molecular weight hyaluronic acid .

According to a report investigating whether macrophage activity differs depending on the molecular weight of hyaluronic acid, it was found that low-molecular-weight hyaluronic acid has an inflammation-inducing effect and high-molecular-weight hyaluronic acid has an anti-inflammatory effect .

Therefore , choosing a high molecular weight hyaluronic acid preparation may prevent delayed inflammatory reactions .

Less cross-linking agent reduces the risk of inflammation

A cross-linking agent is a chemical that acts as an adhesive that binds hyaluronic acid chains together.

Small molecule hyaluronic acid is quickly broken down in the body. Therefore, a cross-linking agent is added to hyaluronic acid preparations for aesthetic medicine, which require a certain level of sustainability.

1,4-Butanediol diglycidyl ether (BDDE) is used as a cross-linking agent in many hyaluronic acid preparations, and the higher the proportion of BDDE, the longer the shape retention .

However, as it becomes more persistent, it becomes less flexible and tends to cause lumps and bumps on the skin, increasing the risk of redness and inflammation .

Cross-linking agents have been shown to affect delayed inflammatory responses. Although cross-linking agents are contained in almost all hyaluronic acid preparations, it is thought that choosing a hyaluronic acid preparation with as few cross-linking agents as possible will reduce the risk .

Kaisense's safety and flexibility to create a natural look

Kaisense is a high molecular weight hyaluronic acid with few cross-linking agents.

Kaisense has the molecular structure of high molecular weight hyaluronic acid, which is less likely to cause an inflammatory reaction . Moreover, it is a hyaluronic acid preparation containing a small proportion of cross-linking agents that can cause unevenness and delayed inflammatory reactions .

The larger the molecular weight of hyaluronic acid, the higher the viscoelasticity of expansion and contraction.

Due to the patented technology, Kaisense, which maintains the chain of high molecular weight hyaluronic acid, does not have a high proportion of cross-linking agent. In addition, since it is said that a high level of forming force and lifting force can be achieved with a small injection amount, the amount of cross-linking agent that enters the body is relatively small .

The reason why Kaisense can keep the molecular weight of hyaluronic acid high is due to the patented "OXIFREE manufacturing method" .

Generally, in the manufacturing process of hyaluronic acid preparations, active oxygen that destroys the molecular structure of high molecular weight hyaluronic acid is generated, but in the manufacturing process of Kaisense, the generated active oxygen is thoroughly eliminated and high molecular weight hyaluronic acid is produced. I succeeded in maintaining the chain.

High uplift and supple finish due to Kaisense

The most important characteristic of Kaisense is that it retains its softness, does not lose its shape, and has a high uplifting force that lifts the skin tissue .

In general, the resistance of hyaluronic acid preparations to collapse is proportional to the hardness, but Kaisense has the suppleness to adapt to the skin tissue while maintaining its shape for a long period of time.

Until now, the harder the hyaluronic acid, the harder it was to lose its shape, but the injection site was tactile, and when touched, it sometimes felt uncomfortable.

On the other hand , Kaisense is supple and flexible so that it matches the movement of the facial expression, so even if you touch the injection site, it will not be rugged and you can expect a natural finish .

It is said that supple elasticity is maintained for a long period of time.

How to inject Kaisense

Basics of hyaluronic acid injection procedure

Proper use of needle and cannula

In hyaluronic acid injection therapy, a sharp needle called a needle and a blunt needle called a cannula are used properly.

The cannula is an injection needle that is longer than the needle and has a rounded tip, and has a hole on the side of the needle for the drug to come out. In addition to less pain and less internal bleeding, good use of the cannula can shorten the procedure time .

However, since it is difficult to inject into a shallow layer or to make a detailed design, use a needle when injecting pinpoint, and use the injection needle properly according to the treatment site and the desired therapeutic effect.

Local anesthesia may not be given with the cannula, but to reduce the pain even a little, even if it is a cannula, using a pain reliever will reduce the burden on the patient.

In addition, the pain can be suppressed by piercing the needle as fast as possible and slowing the injection speed as much as possible .

Injection technique and depth of injection

There are different types of hyaluronic acid injection techniques. Depending on the treatment content, the injection technique is used properly, and the injection is performed according to the purpose by combining and applying it.

linear threading
(Linear threading) method
Injecting into a line such as a nasolabial fold There is a cross-haching method in which it is injected in a grid pattern as an application.
bolus method Inject in dots for volume improvement treatments, etc.
fanning method Inject in a fan shape when lifting on the surface

In addition, there are the following four layers for injection depth.

Superficial dermis A shallow layer that cannot be injected with a cannula, so that the needle can be seen through the skin
Middle to deep dermis A layer where the needle cannot be seen through
Subcutaneous tissue / fat layer If there is a layer resistance that feels almost no resistance to advance the needle, suspect that it is hitting a blood vessel, nerve, or supporting ligament.
On the periosteum A layer where you can easily feel resistance when advancing the needle

Acquisition of anatomical knowledge

Even with a cannula, even with a blunt needle, blood vessels can be damaged and embolism can occur, leading to serious risks such as skin necrosis, cerebral infarction, and blindness.

Particularly dangerous areas are the eyebrows with supratrochlear arteries, the nose with dorsal nasal arteries, and the nasolabial fold with facial arteries. ) . Be aware that you may use a cannula especially in such dangerous areas.

To avoid the risk, it is essential to know where and at what depth the blood vessels pass .

One of the injection methods that avoids risks and produces results is to understand the injection points with "MD-Codes" proposed by Allergan Japan as an injection manual and "True Lift" proposed by Galderma. If you master MD-Codes and True Lift, it will be useful when you make a medical record showing the treatment content and policy.

Preparation of hyaluronidase

Hyaluronic acid complications include infections, allergic reactions, and even more severe cases such as skin necrosis, blindness, and cerebral infarction. Hyaluronic acid can be dissolved by the hyaluronic acid-degrading enzyme "hyaluronidase."

Hyaluronidase is an effective way to remove the hyaluronic acid that causes all complications, and it is imperative that you be ready for immediate action .

Hyaluronidase is injected around a potential embolus. It is not essential to inject directly into the blood vessels. If blood circulation does not improve within 1 to 2 hours after injection, inject again.

In addition, embolization can occur not only at the treatment site but also at the destination where the blood in the blood vessels existing at the treatment site flows. Again, you must have a good understanding of the running of blood vessels, which is anatomical knowledge.

Practice of hyaluronic acid injection

Precautions for injection by cannula

Cannula is said to have less risk of damaging blood vessels and less risk of vascular embolism that cuts off blood flow. On the other hand, it may be easy to get caught in the tissue under the skin and it may be difficult to advance the needle.

When injecting, use the opposite hand to the dominant hand (the hand that does not have a syringe), and proceed while turning the needle tip while adding the image of shifting the ligament that connects the skin and facial muscles to the bone . If it is still difficult , inject a small amount of hyaluronic acid to exfoliate the tissue and create a space .

Also, if you put your finger on the skin to make a block on the part that is not injected, it will be easier to spread it to the required part.

The cannula may seem like a difficult needle to use, but the hole on the side of the needle allows the formulation to be spread over a wide area by injecting while turning, which has the advantage of shortening the treatment time. It can be said that it is big.

Injection method to avoid risk

By using different needles and cannulas according to the site, pain and complications can be reduced.

Even with the use of a cannula, blood circulation disorders and nerve damage can occur. It is a big mistake to say that it is safe to use a cannula, as most cases of blindness occur with a cannula in foreign data.

The key to reducing pain and reducing the risk of complications is to inject in small doses and to ensure that the injection site is well inflated from time to time . If you accidentally inject it into a blood vessel, the injection site will not swell.

It is also important to perform a syringe suction test to make sure there is no backflow of blood, that is, the needle tip is not inside the blood vessel .

Identify the injection site where the effect can be expected with the minimum injection amount

The number of injections must be determined so that the desired change can be seen without any discomfort, while avoiding overfilling and making it unnatural.

For lift-up treatments for people in their 40s and older (treatments that make wrinkles and sagging less noticeable), it is often difficult to see the effect with one, and two to four are often used. It can be expected that it will lead to repeaters by identifying the injection site where satisfaction can be obtained with the smallest possible injection amount and performing the treatment .

Sometimes it is necessary to consider a different injection site than desired. It is important to make a medical examination to determine where the injection is effective and to explain it firmly so that you can understand it.

For anti-aging purposes, the priority of the procedure is mid-face

Facial sagging is caused by bone atrophy and fat transfer due to aging. As a result, the Golgo line is more suitable for people in their 30s and older, and the nasolabial fold or marionette line is more suitable for people in their 40s and older. Therefore, the priority of the injection site is the midface from below the eyebrows to below the nose.

There is also a method of injecting directly into the area with the nasolabial fold, but in recent years, the method of injecting into the anterior medial part of the cheek, the lateral part of the zygomatic bone, and the temporal region has become the standard . It's on the way.

Since the skin is connected, the necessary ridges will eliminate the sagging of the skin and make the Golgo line, nasolabial fold, and marionette line less noticeable.

Cannula is mainly used for mid-face treatment.

First, make an insertion point on the side of the ala of nose and on the extension line below the corner of the eye. Inject from one needle hole into the anterior medial part of the cheek, the lateral part below the cheekbone, and the temporal region while changing the direction of the needle tip. By supplementing the volume of 3 parts with hyaluronic acid, it can be expected that the Golgo line, nasolabial fold, and marionette line due to sagging will not be noticeable.

Cannula also has the benefit of reducing the risk of infection because it requires fewer needle holes .

If 3 sites are not enough, inject hyaluronic acid toward the ear from the first insertion point and the extension of the mouth.

Next to the midface, consider injecting into the lower face.

It is said that it is beautiful when the lengths of the upper face, middle face, and lower face are equal when the face is divided into three parts, but the Asian skeleton originally tends to have a short (small) lower jaw and retract. In addition, age-related bone atrophy causes further receding.

Therefore, a sharp needle is inserted into the tip of the jaw perpendicular to the bone surface, and the hyaluronic acid preparation is injected in dots (bolus method). By injecting hyaluronic acid balls in a vertical stack, the lower jaw will come forward and the profile will be balanced .

By injecting it into the chin, it can be expected to improve the sagging under the chin, and by injecting it into the outer edge of the mandible, the face line will be aligned and a sharp impression will be obtained.

Finally, if you inject hyaluronic acid into your temples with a sharp needle or cannula to compensate for bone atrophy, the rugged face line will become a smooth curve, and you can expect a lift-up effect .

Considering the need for botulinum injection for jaw treatment

If facial muscle movements stiffen the chin and masseter muscles, consider botulinum injection .

Unlike hyaluronic acid, which is expected to have an effect immediately after injection, botulinum injection is said to begin to show its effect about 2 to 3 days after injection, and its effect is maximized and stabilized in about 1 week.

When used in combination with hyaluronic acid, it is recommended to perform botulinum injection first, and then wait about a week before the botulinum injection begins to appear. If you do it on the same day, inject hyaluronic acid first.

Precautions for Kaisense injection

Since Kaisense has a high ability to lift, it is easy for ridges to occur, so inject a small amount while watching the situation .

As a method of injecting hyaluronic acid, there is also a method of modeling while moving it with a finger from above the skin after injection , but with Kaisense, which has high cohesiveness, it is injected evenly and on the surface at the injection stage so that the finish is not bumpy. I will continue to do it.

Technique is required to inject Kaisense without unevenness

MD-Codes has an advantage in reproducibility and ease of confirmation that even a third party can see where and what amount was injected, but in Kaisense, there are cases where unevenness is conspicuous with the MD-Codes method. I have.

MD-Codes is also referred to by intermediate users and above, but it has been developed with a focus on the point that even beginners can easily perform injection treatment. In the early stages, almost all injection sites are unified with the periosteal procedure so that even a first-time doctor can start immediately.

However, technology is required to inject Kaisense evenly and in small amounts without unevenness, and due to its product characteristics, it can be said to be a product for professionals .

Due to its excellent cohesiveness, Kaisense has a strong lifting force even in a small amount, which means that if you turn it over, the bulge will be noticeable even in a small amount.

It can be said that it is difficult to increase satisfaction with the MD-Codes method alone.

Design power and aesthetic sense that leads to satisfaction of hyaluronic acid injection

Hyaluronic acid infusion therapy requires theory and sense to determine the right injection site for the person.

It is important to acquire design ability and aesthetic sense in order to perform treatments that satisfy patients.

It is also important to acquire a sense of overall balance so that the patient does not "look at the trees and see the forest" rather than focusing on the specific part that the patient is suffering from.

Recently, injection techniques aimed at lift-up have become popular, and the number of cases of excessive injection is increasing due to the demand for lift-up. As some KOL et al. Propose that it is over filled syndrome, be careful not to overfill it .

In addition, it is necessary to have the ability to explain the finished image as well as the design ability so that the person does not feel "failed".

To cultivate design power and aesthetic sense

There may be geniuses who have a natural sense and skill, but I think that sense and skill are acquired after studying and training a long and rugged foundation.

I feel that it is necessary to come into contact with art in a wide range of fields in order to improve your artistic sense . I don't think people who haven't touched art have a sense of art.

Finding a doctor from art school can be extremely difficult, but a doctor with a deep knowledge of music, fashion, and art may have a good taste.

What is the aesthetic sense of the doctor?

There should be many patients who refer to the conversation in counseling, the furniture and other interior sense in the hospital, the appearance of the doctor, as well as the nurses and reception staff . Medical institution staff usually have some kind of treatment.

In addition, there are many cases in which a female doctor treats herself by herself in the case of the owner's director. It can be said that the finish of the doctor himself is also attracting attention .

Kaisense is an unapproved drug from the Ministry of Health, Labor and Welfare.
Drug acquisition route: The acquisition route is individual import from the manufacturer by the doctor of each medical institution.
Drugs to be aware of when importing personally (Ministry of Health, Labor and Welfare page)
Whether or not it is approved in Japan: There is no drug that has the same ingredients and actions as Kaisense and has been approved in Japan.
Information on safety in other countries: According to KYLANE, the developer of Kaisense, the CE mark certifying safety and quality in Europe has been obtained by the certification body 2797 BSI Group based on MDR. It has been. No serious adverse events have been reported in other countries.

Introduction of supervising doctor

Dr. Hidekatsu Shinohara, the founder of Skin Refine Clinic and the director of Skin Refine Clinic Ginza. In injection of hyaluronic acid and botox, he gives guidance to doctors as an injection instructor. As a certified specialist of the Japan Society of Plastic and Reconstructive Surgery, we provide careful counseling and perform a wide range of treatments from injection treatment to laser treatment and phototherapy.

Medical institution with Dr. Hidekatsu Shinohara

Skin refine clinic Skin Refine Clinic Ginza
Contact: 0120-661-062