Keloids%20and%20hypertrophic%20scars Treatment

Silicone Therapy

• Gold standard in scar management & first-line non-invasive treatment option for hypertrophic scars & minor keloids
  
  • Preferred first-line due to its non-invasiveness, availability, ease of use, lesser adverse effects, & efficacy
  • Used alone or in combination w/ add-on therapies for all mild-moderate pathologic scars
  • Also used for severe scars after surgical excision

• It should be used as soon as the wound/suture is healed but some silicone therapies can be applied to open wounds
• Easy to use w/ minimal side effects such as pruritus, contact dermatitis & dry skin
• The most commonly used medical silicone is the inert polymer polydimethylsiloxane
• Silicone sheeting consists of a soft, semi-occlusive gel sheet made from medical-grade silicone that is reinforced w/ a silicone membrane backing to give the sheet increased durability & ease of handling
  
  • Silicone gel sheeting has been shown to have the ability to hasten hypertrophic scar maturation & decrease associated symptoms of pain, rigidity & pruritus
    
    • Occlusion w/ silicone gel sheeting decreases scar hypertrophy & reduces tension or stabilization effect in scar management
  • Silicone elastomer sheeting is usually used for 12-24 hours per day for 2-3 months

• Recently, a self-drying silicone gel has been developed wherein the fluid silicone gel is applied in thin layer to the skin & when it dries it forms a transparent, flexible, gas-permeable, water-impermeable silicone sheet
  • This preparation provides “round the clock” coverage & can be used for closed wounds

• A film-forming silicone gel-based wound dressing has been approved for open & closed wounds & compromised skin to protect it from microbial & bacterial infection
• Silicone-based gel is as effective as silicone gel sheeting
• In a randomized, double blind controlled study it was found that in sternotomy wounds, silicone gel minimizes the formation of hypertrophic scars in the early postoperative stage
  
  • It also shows that the silicone gel reduces pigmentation, vascularity, pliability, height, pain & itchiness

Intralesional Corticosteroids (eg Triamcinolone acetonide)

• Given intralesionally as treatment for small & younger keloids as well as hypertrophic scars
  • Usually given in 2-3 injections a month apart for 6 months
• Provides symptomatic relief by decreasing pruritus
• Corticosteroids have suppressive effects on the inflammatory process in the wound & mitosis while increasing vasoconstriction in the scar
• May be combined w/ cryotherapy that has shown to improve outcome in more than one modality alone, although hypopigmentation is always a significant concern
• Injection should be limited to the scar itself & injection into the periscar tissue must be avoided as this may cause underlying fat atrophy

Intralesional 5-Fluorouracil

• Treatment option for therapy-refractory keloids & as intralesional injection in patients w/ linear hypertrophic scar
• As a pyrimidine analog, it inhibits the proliferation of fibroblasts & has been shown to treat inflamed hypertrophic scars
• Combination w/ Triamcinolone results in shrinking of keloids while avoiding tissue atrophy & telangiectasia that may occur w/ repeated corticosteroid injections

Other Dermatologicals
Onion Extract-Based Topical Preparations

• Adjunctive therapy for active hypertrophic scars
• May be used in widespread burn hypertrophic scars although there are few evidences available
• Inhibits fibroblast proliferation & collagen production by the flavonoids in onion extract (extractum cepae)
• Acts as an anti-inflammatory & bactericidal agent
• Recent studies show that it improves scar height & associated symptoms, though further studies are needed to confirm efficacy
• Appeared to be effective for the prevention of unpleasant scars in patients having laser removal of tattoos & in combination w/ intralesional Triamcinolone acetonide in recent studies
• Reviews show mixed results; further studies are needed to confirm efficacy

Emerging & Investigational Therapies

Bleomycin

• Alternative therapeutic option for severe scars
• Inhibits collagen synthesis via decreased stimulation by TGF-beta1
• Some studies showed significant improvement in hypertrophic scar & keloid height & pliability & decrease in erythema, pruritus, & pain
• Side effects are depigmentation, dermal atrophy & some toxicity
• Further studies are needed to include this as part of the treatment protocols

Botulinum Toxin A

• May present  as a novel therapeutic option for the aesthetic improvement of post-surgical scars
• Immobilizes local muscles, decreases tensile forces on post-surgical scars, hereby decreasing microtrauma & subsequent inflammation
• Clinical efficacy of intralesional botulinum toxin A for the treatment of existent keloids remains uncertain

Imiquimod

• Can be considered treatment options for refractory keloids but currently not approved in this indication
• A topical immune response modifier that stimulates the production of interferon that leads to increased collagen breakdown

Interferon

• A promising therapeutic option for keloids resistant to any other treatment but needs further studies to establish a role in the prevention & management of pathologic scarring
• Findings showed that it decreases collagen synthesis that provides improvement of excessive scars
• Option as intralesional injection in patients w/ linear hypertrophic scar

• Can be considered treatment option for refractory keloids & severe scars
• There are limited available studies that merit as treatment consideration for hypertrophic scarring

Moisturizers (emollients, humectants)

• Helps relieve symptoms such as itchiness & rigidity

Retinoic acid (Vitamin A derivatives)

• Markedly reduce fibroblast proliferation by interfering w/ DNA synthesis & exhibit an inhibitory effect on TGF-beta1-induced type 1 collagen gene expression in the fibroblasts
• Studies have shown marked reduction in scar size & decreased pruritus of intractable scars
• Some suggests that low-dose of Isotretinoin may be used in the treatment of acne kelodalis
• Should not be considered as first-line therapy for keloids

Verapamil

• A calcium channel blocker that decreases collagen synthesis & increases collagen breakdown
• Currently have insufficient evidence to recommend use in routine clinical practice

• A recent study has shown that topical application containing Vitamin C in a silicone gel reduced permanent scar formation in an Asian population
• A water-soluble antioxidant that regulates collagen biosynthesis & regenerates vitamin E
• As a depigmenting agent, Vitamin C reduces formation of melanin & also acts on the perifollicular pigment
• Glycosaminoglycan helps in the effective skin penetration of Vitamin C

• Both keloids & hypertrophic scars respond to the same therapies, but hypertrophic scars are easier to treat & have a better prognosis

Pressure Therapy

• Decreases oxygen tension in the wound by decreasing collagen synthesis limiting capillary perfusion
• Increased pressure in the matrix regulates apoptosis of dermal fibroblasts & diminishes the hypertrophic process
• Uses pressure suits or bandages w/ transparent plastic marks or pressure buttons in special locations
• Alleviates edema, itchiness & pain
• Side effects such as eczema, maceration, & odor emanating from the pressure garment may cause non-compliance to this therapy
• It can be an alternative to intralesional corticosteroid or cryotherapy for treatment of hypertrophic scars & keloids in younger children
• Pressure garments use showed better results in children compared w/ adults

Other Non-pharmacological Therapies

• Massage therapy
• Static & dynamic splints
• Psychological counseling

• Effective treatment for older hypertrophic scars & larger keloids when combined w/ intralesional Triamcinolone acetonide
• It freezes the scar tissue from the inside out that decreases the scar volume
• It also induces vascular damage that leads to anoxia & tissue necrosis
• Alternative therapeutic option for severe scars

• Most commonly used lasers in the treatment of hypertrophic scars & keloids are:
  
  • Pulsed dye laser (PDL)
  • Fractional carbon dioxide (fCO₂) laser
  • Intense pulsed light (IPL)

• Pulsed-dye laser or ablative fractional laser therapy is indicated in the following:
  
  • Immature or linear hypertrophic scars that have persistent erythema (>1 month) even after preventive measures were done
  • Widespread hypertrophic burn scars that have not improved despite treatment for 8-12 weeks w/ silicone gel or sheeting, pressure garments &/or onion extract preparations
  • Minor keloids that have not improved after 8-12 weeks of silicone gel sheeting & intralesional corticosteroids
  • Major keloids that have not improved after treatment w/ intralesional corticosteroids & 5-FU

• Pulsed-dye laser showed significant improvement in erythema, pruritus, & scar height that persists for at least 6 months
  • Principal effect is on scar microvasculature, decreasing erythema & pruritus & improving skin texture

• Has shown to improve keloids or hypertrophic scars by inducing capillary destruction which generates hypoxemia & alters local collagen production by increasing collagenase
• Non-overlapping laser pulses are currently recommended
• 2-6 sessions are needed to successfully improve scar color, height, pliability & texture
• Side effects include purpura, vesicles, crusts, hyperpigmentation, erythema, & reactivation of younger keloids
• Nd:YAG laser that is short-pulsed, low-fluence & 1064-nm has been analyzed to be safe & effective in the treatment of facial acne scarring
• Improvements in clinical & structural features of burn scars were reported w/ fractional CO₂ laser therapy & is preferred for keloids
• The fractional ablative CO₂ laser has been shown to be highly effective in the treatment of hypertrophic scars, including cosmetic & functional enhancement of traumatic scars & contractures, w/ treatment ranging between 1 & 6 sessions
• Intense Pulsed Light (IPL), although not technically a laser, delivers focused controlled light energy through a coupling gel across the 515-1200 nm spectrum & at a fluence of up to 40 J/cm²
  
  • Multiple studies have shown that IPL is helpful in the management of burn scar dyschromia, long-standing hypervascularity, & chronic folliculitis without the risks or downtime of PDL photothermolysis or laser resurfacing