TCA Cross for acne scars

What is TCA Cross?

TCA Cross is a medical treatment where our doctors apply TCA to individual scars. The skin turns white as a chemical reaction between the proteins in the skin and the TCA occurs. This produces a medium-depth to deep chemical peel exactly in the scar. The skin layers lining the scar peel, and the tissues beneath produce more collagen. This new collagen fills up the scar from below, with new skin tissue. The scar also tightens and shrinks.

TCA Cross is a chemical peel treatment for acne scars offered across our clinics in London. It is a high strength chemical peel for ice pick acne scars, boxcar acne scars and dilated pores. This is an advanced medical treatment and performed by our highly skilled doctors only. Our doctors are very experienced at performing TCA cross and have been offering this treatment for over 10 years. We offer TCA and phenol for CROSS treatment of acne scars. To our knowledge, we are the only Clinic in the UK to offer both category of specialist CROSS peels.

TCA stands for the chemical peeling agent Trichloracetic Acid. CROSS stands for Chemical Reconstitution Of Skin Scars.

What is the difference between a TCA peel and TCA Cross?

TCA Cross is a form of TCA Peel. However, when talking about a TCA peel most people are referring to lunch time peel. Lunch time peels have very low concentrations of TCA from 10 to 15% and are painted on the whole face. They are great for freshening up the skin by removing dead cells and stimulating skin turn over. Lunch time peels are superficial chemical peels. Examples of superficial peels containing low concentrations of TCA are Easy TCA, Alumier Peels and VI Peels.

TCA Cross involves using very strong concentrations of TCA – from 70 to 90%. This makes the depth of the peel much deeper than lunch time peels.

Frosting from TCA Cross for Acne Scars

What is TCA cross used for?

TCA Cross is an effective treatment treatment for deeper types of acne scars such as:

  • Ice pick acne scars
  • Skin pits
  • Pitted scars
  • Dilated pores and open pores
  • Boxcar acne scars

Other treatments may not reach right down to the bottom of deeper acne scars where as TCA cross does. For example microneedling, laser and radiofrequency may might not reach the scar base. Think of TCA cross as healing the scars from ‘below’.

Our dermatologists also treat other scars with TCA Cross including

  • Chicken pox scars. This medical report showed that 4 treatments of 100% TCA Cross given every 2 weeks led to a good or excellent improvement in all 13 patients of Indian skin type (4).
  • Traumatic scars

More information on our acne scar treatments can be found here.

TCA Cross Key Points

  • Why – Trichloracetic (TCA) acid is applied to individual acne scars usually as part of an acne scar treatment program
  • Where – Face
  • Frequency – TCA Cross is done every 4 to 6 weeks. Between 3 to 6 treatments are required.
  • Results – Within a few weeks
  • Downtime – 5 to 7 days

What does TCA Cross treatment involve?

Once your Dermatologist has prescribed a course of TCA Cross for your acne scars, treatment can begin. The Dermatologist will clean the skin to remove skin greases and mark out the scars for treatment. The doctor will then stretch the skin and apply the 90% TCA Cross to the base of the scar with a wooden stick or needle. The scar will turn white in 10 to 15 seconds. You will feel a slight pressure during the treatment and a tingling or warmth straight after. The procedure is not painful. A parfaffin based ointment goes on straight following this. The procedure takes between 10 to 15 minutes. It’s best to leave the areas open and not cover them with make up.

What happens after the procedure?

The sequence of healing after TCA cross is:

  • frosting which last 30 minutes.
  • redness which lasts 1 or 2 days
  • scabs which last 3 to 7 days
  • redness after the scabs separate which lasts 7 to 28 days
  • final healing

The frosting (which is the white colour) clears up after a few hours and the skin becomes red and sensitive. The redness goes after 1 or 2 days. Small scabs then form which usually look dark. It is best to keep the scabs soft, rather then let them dry out, by applying a dab of vaseline three or four times a day. Cetaphil lotion is ideal for cleansing the skin twice a day. The cleansing routine also helps scabs separate when they are ready.

The scabs take about a week to separate. Don’t pick them off as it can interfere with the healing process. The scabs may be slightly wider than the area of the scar. They will come away of their own accord, when they are ready. It is OK to wear make up on day 3 but the scabs are not that obvious to cover. Once the scabs have separated, the area may still look red for some weeks until all the healing is complete.

Preparing for TCA Cross treatment

Keep out of the sun and avoid getting a tan (even a slight tan). Wear a hat and a factor 50 sun screen for 2 weeks before treatment and for 2 months after treatment. This will reduce the chance of pigmentation change from treatment. Your Dermatologist may ask you to use a topical retinoid before treatment. Your doctor may also prescribe a skin pigment stabiliser such as Hydroquinoine or Kojic acid before or after treatment. The items you need for treatment are :

  • A small new pot of Vaseline to apply to the scabs four times a day
  • Cetaphil lotion to wash with twice a day
  • Factor 50 sunblock
  • A hat
  • A tinted moisturiser or make up from day 3

Will I need more than one treatment?

Yes, a three to six treatments produce the best results. Each treatment can be four to six weeks apart.

What are the results like?

In our experience, TCA is a very successful treatment. Three quarters of patients feel they have ‘good’ or ‘excellent’ results from treatment.

What are the risks of treatment?

In the context of any medical treatment it is important to understand that there are risks. The risks of TCA cross treatment include :

  • Redness can linger on for several months.
  • The areas can become darker (hyperpigmented) – this is usually temporary
  • The areas can become paler or white (hypopigmented) – this is also usually temporary but can be permanent
  • Some people don’t very strong or visible results, and some people get no results
  • Scars can widen
  • Rarely a skin infection can occur

How quickly are results seen after TCA Cross?

Improvement after TCA Cross can be seen in as quickly as 3 or 4 weeks after the first treatment. Sometimes a response is not seen after the second or third treatment. If there is no improvement after 3 treatments then the course is usually stopped.

Are the results of TCA Cross permanent?

Yes, as the collagen produced from TCA Cross is your own, the results are permanent.

Is TCA cross safe in darker skin types?

Providing all the precautions with sun exposure are followed, treatment is safe in darker skin types up to Fitzpatrick skin type 5.

The first medical report for TCA Cross from South Korea showed that it was safe in Far Eastern Skin types (See Reference 1 below). There were no complications in 33 patients who had 65% TCA and 32 patients who had 100% TCA. The patients were Fitzpatrick skin types 4 and 5.

Subsequent medical reports from India, Egypt and Brazil have shown TCA cross to be safe in a darker skin.

Peeling agents for CROSS – Chemical Reconstitution Of Skin Scars

Research has show that a variety of concentrations of TCA have been shown to be safe and effective. Phenol peels have also been shown to be safe and effective. We offer both TCA and phenol preparations for CROSS management of acne scars.

  • A Korean medical report showed that 100% TCA produced better results than 65% TCA. 82% in the 65% TCA group and 94% in the 100% TCA group had a good clinic response. Complications were not reported in either the 65% TCA or 100% TCA group (See Reference 1 below).
  • An Italian report showed that 50% TCA cross was also effective but it did not compare it to other concentrations – see Reference 2 below
  • An Egyptian study showed that 100% TCA improved scars by 75%. 4 sessions were given.
  • An Indian study showed that 70% TCA was effective (Reference 6)  and a Brazilian study showed 90% TCA was effective (Reference 7)

Combining TCA cross with other acne scar treatments

TCA cross lends itself well to being combined with other acne scarring treatments. Treatments that complement each other will improve acne scars faster. This is because the same scars are treated by different methods, and adjacent scars are also treated. This can give a greater tightening and remodelling of the skin. Your Dermatologist may recommend combinations including :

  • TCA Cross and Subcision – to free scars from deeper tissues
  • TCA Cross and Tixel – fractional resurfacing with heat
  • TCA Cross and Laser resurfacing – fractional resurfacing with laser
  • TCA Cross and Microneedling

It is possible to combine subcision, TCA cross and Tixel in the same session.

What are the alternatives to TCA Cross?

TCA Cross is unique in the way it works because of two reasons. The first is that it reliably reaches the depth of acne scars, where as may treatments may not. The second is that TCA stimulates tissue tightening, new collagen formation and tissue remodelling. This is over and beyond from just the injury-healing effect.

There is no direct alternative to TCA Cross because of its unique reach and how it works. Howver, other treatments may be more suitable or required in combination. For example, some icepick and boxcar scars will need surgical removal. Others will need subcision and fillers. Sometimes a full face resurfacing treatment will be better especially if the scars are shallow.

What should I do next?

If you would like to consider TCA Cross then please arrange to see one of our Dermatologists  in London who will be happy to help. You will receive our expertise in this area:

  • Detailed consultation by a Dermatologist to design an individualised treatment plan
  • TCA Cross may be prescribed alone or in combination with other treatments for acne scars
  • TCA cross is a very safe and effective treatment when delivered by specialist doctors. Our Dermatologists are among the few specialists in London offering TCA Cross treatment.
  • We offer both TCA Cross and Phenol Cross and we frequently combine treatment with other advanced acne scar treatments such as Tixel, subscision and laser resurfacing

Important medical reference papers for TCA Cross.

1. Focal treatment of acne scars with trichloroacetic acid: chemical reconstruction of skin scars method (2002).

This was the first medical report for TCA cross by Dr Lee in South Korea. It showed TCA Cross was safe in dark complexioned people. 100% TCA produced superior results to 65% TCA. There were no complications.

2. CROSS technique: chemical reconstruction of skin scars method (2008). 

This is an Italian report showing 50% TCA is also effective.

3. Percutaneous collagen induction versus full-concentration trichloroacetic acid in the treatment of atrophic acne scars (2011).

This is an Egyptian paper showing that 100% TCA was safe in Egyptian skin type patients.

4. Chemical reconstruction of skin scars therapy using 100% trichloroacetic Acid in the treatment of atrophic facial post varicella scars: a pilot study (2013). 

This is a report of 100% TCA showing it was safe and effective in Indian patients with chicken pox scars.

5. Evaluation of CROSS technique with 100% TCA in the management of ice pick acne scars in darker skin types (2011). 

This report showed that 100% TCA was safe and effective in Indian patients of skin type 4 and 5. Of 30 patients, 73% had an excellent improvement, 20% had a good improvoement, and 7% had a fair improvement. No cases had permanent pigmentation issues though one patients suffered from transient hypopigmentation and two had transient hyperpigmentation.

6. Therapeutic response of 70% trichloroacetic acid CROSS in atrophic acne scars (2015). 

This Indian study used 70% TCA every 2 weeks and found that 66% of 53 patients had good or excellent improvements. Boxcars did very well.

7. Comparative Study of the Use of Trichloroacetic Acid and Phenolic Acid in the Treatment of Atrophic-Type Acne Scars (2016). 

This study from Brazil showed that 88% phenol was also as effective as 90% TCA for treating atrophic acne scars. Persistent loss of pigmentation and widening of the scar was noted in relation to TCA treatment.

“TCA Cross can provide excellent results in improving acne scars.”

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