Although Keloid and Hypertrophic scars appear somewhat similar, they are not the same. Most people confuse these two types of skin lesions because they lack morphological differences.
If you are wondering, “do I have a Keloid scar or a hypertrophic scar”? This piece will help you differentiate between these two types of scarring. This way, you can identify the next step you need to take in treating them.
To start with, let’s define the two terms:
Definitions:
What is a keloid scar?
A keloid is a pinkish, purplish, or flesh-colored smooth, but hard or firm mass that forms around an injured area. The scar forms immediately after an injury or months later.
Keloids are itchy and cause some level of discomfort. Also, they tend to extend over and above the original wound.
Although upper chest, shoulders, and earlobes are more to prone to keloid formation, these scars can form on any part of the body. Dark-skinned people are more susceptible to keloids than Caucasians. A keloid doesn’t cause any harm to general health and doesn’t change into skin cancer.
What is a hypertrophic scar?
Unlike keloids, a hypertrophic scar is a red, thick and raised scar. It forms when there is excess tension around a healing wound. This scar flattens after several months and becomes flat and pale.
The healing area is thicker than usual when there’s lots of tension on a healing wound. This scar does not extend over to other regions like keloids and is only limited to the damaged skin.
To better understand the difference between keloids and hypertrophic scars, have a look at this table that compares each feature of the two types of scarring against each other.
Keloids vs Hypertrophic Scars
Causes of Keloid and Hypertrophic Scars
Keloid and hypertrophic scars are raised scars resulting from chronic inflammation in the reticular dermis skin layer. Both are caused by either physical trauma or chemical Irritation.
It forms after cutaneous irritation or injury caused by incision, burn, insect bite, skin piercing, surgery, vaccination, chickenpox, folliculitis, and herpes zoster infection. However, keloids form even from minor scratches like acne scarring.
Prevention Tips
Before undergoing any surgical procedure, patients should disclose if they have had any previous severe scarring issues. This reveals some potential for keloids and thus will help make an informed consent.
People with dark skin or previous problems with scarring are discouraged from undergoing any elective procedures, including ear piercings. If the procedure must occur, then using pressure earrings may help reduce the risk of developing keloids.
For high-risk patients, for example, those with high-risk pregnancy and have to undergo CS or seriously sick and have to go through an operation, then the use of corticosteroid injections or silicone sheeting is highly recommended.
Anything that may help diminish skin tension or accelerate wound healing such as postsurgical taping for 12 weeks can also reduce the risk.
Treatment of Keloid and Hypertrophic Scars
Both Keloid and hypertrophic scars respond to the same therapies. However, it’s easier to treat hypertrophic scars than keloid scars.
Several treatment modalities help in reducing the inflammation, including, cryotherapy, corticosteroid injection, ointments, compression therapy, radiotherapy, 5-fluorouracil (5-FU) therapy, stabilization therapy, and surgical methods to reduce tension.
The first line of treatment includes silicone sheeting, corticosteroid injections and pressure treatment. These treatment methods should be followed and adhered to exemplarily for them to be effective.
Removal of keloids surgically is the second line of treatment. This work only temporary and even more aggressive regrowth of scar tissue may follow unless you combine it with the other treatment methods. Therefore, if you undergo surgery, you should follow it up with other treatments, including silicone sheeting, corticosteroid injections, or these options combined with pulsed dye laser.
Cryotherapy is only effective for smaller lesions like those that result from acne. Cryotherapy in patients with dark skin may cause hypopigmentation.
So how do these treatment modalities work?
Silicone Sheeting
Studies show that silicone elastomer sheeting can not only prevent the formation of keloid and hypertrophic scars but also it helps treat them. Silicone sheets increase the hydration, temperature and perhaps oxygen tension of the obstructed injury which, in turn, help soften and flatten the scar.
Silicone sheeting should never be used in open wounds, but it comes in handy when the skin starts to heal. For the sheet to be useful, it should be worn over the scar for between 12 and 24 hours in a day for two to three months.
Washing the scar and the sheet daily with mild soap and water is vital. Silicone sheets can be reused until they begin to disintegrate.
Corticosteroid Administration
Corticosteroid, ointments, injections, and tapes/plasters can effectively treat hypertrophic and keloid scars. They have an anti-inflammatory effect, and the steroids also induce vasoconstriction.
Corticosteroid administration causes keloids to whiten, which suggests that the blood flow in the scar has reduced by vasoconstriction. Moreover, it helps quickly reduces the pain and itching associated with Keloids.
Apart from the steroid injection, steroid tape has also been effective in reducing inflammation of hypertrophic and keloid scars. When using steroid tapes/plasters, make sure that you change them after every 24 to 48 hours. Trim them well to only cover the wound with no or minimal attachment to the healthy skin. These tapes differ in strength, so selecting them on a case-by-case basis is highly recommended.
If neither the silicone sheeting nor the corticosteroids administration has worked for over 12 months, the second line of treatment is surgery. This should be followed by corticosteroid and perhaps silicone sheeting.
Surgical Methods
Surgery is one of the best treatment methods for keloids and hypertrophic scars. It can help reduce tension along the wound edges, which decreases skin inflammation. Some of the most effective surgical techniques include z-plasties, subcutaneous/fascial tensile reduction sutures or the local flap transfer.
Keloids scars are stubborn to treat as they have a strong level of inflammation. These scars are likely to reoccur even after treatment. The best way to decrease the reoccurrence of keloids is to combine different treatment methods including surgery, steroid injections, laser treatments and radiotherapy.
Keloid surgery treatment works, but it has to be followed by steroid administration or radiation therapy.
Radiotheraphy
Studies reveal that radiotherapy can effectively prevent and treat keloids scars. While it is said to act by suppressing fibroblast activity primarily, it’s vital to note that endothelial cells are pretty sensitive to radiation than fibroblasts.
Radiotherapy suppresses the angiogenesis which in turn helps decrease inflammation and prevents the formation of dysfunctional blood vessels and, as a result, it suppresses the development of keloids. When patients with severe keloids are subjected to radiation monotherapy, color improves almost instantly and the scar becomes flatter progressively.
IMIQUIMOD
Imiquimod 5% cream (Aldara) may help prevent keloid recurrence after surgery. It’s an immune modifier that helps enhance healing. You can apply the cream on alternate nights for 8 weeks after surgery.
OTHER THERAPIES
Laser Therapy
Pulsed Dye Laser type of treatment is more effective if used in conjunction with other therapies in the early stages. It is more vascular-specific compared to other laser therapies and it helps reduce erythema and pruritus and improving skin texture.
Compression Therapy
Compression therapy is used to reduce the subjective and objective symptoms of hypertrophic and keloid scars. It works by occluding the blood vessels thus inhibits the inflammatory signals that are coming from the blood vessels.
Stabilization Therapy
Since stretching a wound can induce inflammation of the reticular dermis, the use of external mechanical support is recommended to stabilize the injury. This can be through the use of sheets, or tapes, to prevent scarring.
5-FU Therapy
Doing this therapy after surgery prevents the recurrence of keloids. The treatment also helps reduce scar inflammation.
Cryotherapy
This therapy has been effective in treating keloids. It can work alone or in conjunction with intralesional triamcinolone injection. Cryotherapy is delivered through sprays, contact or with the use of intralesional needles.
Apart from those, some of the other effective therapies include stem cell therapy, fat grafting/lipofilling, and electrochemotherapy.
Conclusion on Keloid vs Hypertrophic Scars
While Keloid and hypertrophic scars form in almost a similar manner, there are notable differences between these two types of skin lesions. It’s vital to understand them to be able to prevent or treat them.
