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Hypertrophic scar

Hypertrophic scar following surgical operation

Keloid chest

Keloids on the chest developing in acne scars

Keloid shoulder

Keloid on shoulder developing in acne scar

keloid chest

Keloid on anterior chest. No known trigger.

A keloid is a thickened scar that forms typically after injury to the skin.

Common causes of keloids

  • Acne

  • Surgery

  • Trauma

  • Burns

  • Insect bites

  • Ear piercing

  • Body piercing

A keloid projects beyond the margin of the intitial injury. In contrast, a hypertrophic scar is thickened but does not protrude beyond the margins of the initial injury. The difference is in the degree of thickening.
Keloid chest  before

Keloid on anterior chest before treatment

Keloid scar smooth

Keloid with silicone gel sheet (Scarsmooth)

Keloid after

Keloid after treatment with Scarsmooth.

Treatment of keloids

In a study involving 224 patients who used silicone gel sheets for scars, significant improvement was seen in the colour, thickness and elasticity of hypertrophic (thick) scars and keloids (J Clin Aesthetic Derm 2016 Oct 9(10). 28-35)

More about intralesional Cryotherapy

Intralesional cryotherapy involves passing liquid nitrogen through a keloid.

The keloid is first injected with local anaesthetic to make it numb.

An 18 Gauge needle is then passed through the keloid. This needle is connected to a liquid nitrogen canister via a Luer lock. Once connected, the trigger of the liquid nitrogen canister is pulled and nitrogen passes through the needle.

The process is continued until the entire keloid freezes - visible as turning white in colour.

The needle is then removed and keloid is allowed to thaw.

What should I do if I have side effects?
Please get in touch with the rooms to discuss the issues and get some guidance. You may be called in.
If you are not able to make contact eg at night, public holidays, during congresses etc, please be aware that there is a full time doctor at the A+E department of Westville Hospital who could take care of the emergency.

Is the process painful?

The procedure is performed under local anaesthesia, into other words, the keloid is made numb but you are wide awake. You will feel the initial prick when the local anaesthetic is administered but you feel nothing when the liquid nitrogen is passed through.

Is there pain when the anaesthetic wears off?

This is possible, especially on the day of the procedure and the next day, and can be controlled with pain killers eg Myprodol.

How long does the procedure take?

Once the keloid is made numb, the passing of liquid nitrogen through it takes only a few minutes - usually 1 to 3 minutes - depending on the size of the keloid.

How many sessions are required?

This varies according to the size of the keloid. Small keloids require about 3 sessions of treatment. Larger keloids may require about 7 to 10 treatments. At each visit, the keloid is assessed for response. The treatment is continued only if a positive response is seen ie. keloid getting smaller.

How many treatments are required before one notices improvement?

It is common to see an improvement after the first treatment and with each subsequent treatment. If no improvement is seen after the third treatment, it is better to consider an alternate form of treatment.

Can the treated area bleed. If so, what should be done?

Yes, the area can bleed. If you are on any blood thinning agents, be sure to let the doctor know about it so that you could stop the medication a few days before the procedure. If on no blood thinning agents and the area bleeds after the procedure, all you need to do is to press gently on the bleeding area for about 10 minutes without lifting your fingers to check. The blood will usually clot in that time and the bleeding is expected to stop. 

Can the area ulcerate?

Although the aim is to freeze the inside of the keloid, some freezing does occur on the outside. For this reason, the outer layers of skin can be lost resulting in ulceration of the skin. Please treat the ulcer in the following way:

1. Clean the area with dilute savlon

2. Apply Bactroban/Supiroban/Nuban or equivalent\

3. Cover the area with jelonet (to present the area from sticking on the gauze)

4.  Cover with gauze.

5.  Strap with micropore.

The duration of treatment could be up to a week.

Is it possible to see how the procedure is performed?

Please watch this video on intralesional cryotherapy on our Instagram page (@drnraboobee), showing Dr Raboobee performing this procedure (shown with patient consent)

Here is another example:

How does this procedure differ from intralesional corticosteroid injections for keloids?

The substance injected differs.

Here is a video on the latter procedure:

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