3. INTRODUCTUON
• Keloid is defined as an abnormal scar that grows beyond the
boundaries of the original site of skin injury.
• Alibert in 1806 called it “cheloide” which is derived from
Greek word “chele” or “crab’s claw.”
• Hypertrophic scar is defined as a widened or unsightly scar
that does not extend beyond the original boundaries of the
wound.
• They are inflammatory disorders of the reticular dermis due
to aberrant wound healing process.
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5. Scar classification
• Immature Scar
• Mature Scar
• Linear hypertrophic Scar
• Widespread hypertrophic scar
• Minor keloid
• Major keloid
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6. Epidemiology
• Only humans are affected.
• Occur in 5-15% of wounds.
• All ethnic background can form hypertrophic scar and keloid-
which has greater frequency in pigmented races (16%).
• Young F>M ; other age groups , equal.
• More in the 10- 30 years, less at extreme of age.
• No racial or familial preponderance for hypertrophic scar.
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12. Phases of wound healing
• There are 3 phases of wound healing and can take months to
complete
• Inflammatory Phase: Platelet degranulation---release &
activation of numerous cytokines--chemotactic agents for
inflammatory cells, epithelial cells & fibroblasts
• Proliferative Phase: Stage of granulation tissue formation
• Remodeling Phase : Conversion of Collagen III → Collagen I
14. AETIOPATHOGENESIS(Hypertrophic scar)
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• Scar remains in the remodeling phase more than normal scar.
• There is increased deposition of collagen.
• Commonly occurs in situations when wound is sutured under
tension or healing has been delayed
15. AETIOPATHOGENESIS(keloid)
• Imbalance in anabolic and catabolic phases of wound healing.
• Abnormal keratinocyte-fibroblast signaling .
• Increased level of fibronectin and adiponectin.
• Role of melanocyte stimulating hormone.
• Genetics – DeHaNp63, p53 underexpression.
• Allergic immunoglobin E mediated response.
• Role of TGF-b, PDGF, IGF 1, IL-6 in the invasive activity of
keloid.
• Spontaneous keloids.
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17. • Hypertrophic scar contains islands composed of aggregates of
fibroblasts, small vessels and well organised type 3 collagen
throughout the dermis.
• Keloids contains disorganised type 1 and 3 hyalinized collagen
bundles that form acellular node like structures in the deep
dermis with paucity of cells centrally.
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19. Typical histopathological findings
• Presence of keloid hyalinized collagen
• Tongue-like advancing edge underneath normal-
appearing epidermis and papillary dermis
• Horizontal cellular fibrosis bands in the upper
reticular dermis
• Prominent fascia-like fibrous bands
• Collagen bundles are thicker and more abundant in
keloids; and there is the presence of large, broad &
closely arranged collagen fibres composed of
numerous fibrils
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22. CLINICAL FEATURES
Cinical features Hypertrophic scar Keloid
Always preceded by injury yes no
Anatomical association no yes
Extent of growth limited to wound Extends beyond the wound
Resolves Spontaneously Yes No
Recurs after surgery No Yes
Physical examination Raised erythematous
lesions
Raised erythematous
lesions
Physical examination Soft , doughy, rubbery and
hard
Soft , doughy, rubbery and
hard
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Adapted from Dr Achebe U lecture note
33. Diagnosis
• Diagnosis is usually based on the clinical findings.
• Biopsy may confirm the diagnosis in equivocal cases.
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34. MANAGEMENT OF HYPERTROPHIC SCAR
• Patience and counseling.
• Massage, Pressure, Silicon sheet or gel will accelerate
maturation.
• Wide spread large hypertrophic scar may require serial
excision, intralesional therapy and tissue expansion.
• Surgical intervention, if hypertrophic scar is interfering with
function.
• Surgery involves, scar release or revision, z-plasty, skin flap or
grafting.
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37. Prevention of Keloids
• First rule in keloid therapy.
• Avoid nonessential surgery in keloid formers.
• Close all surgical wounds with minimal tension.
• Incisions should not cross joint space.
• Avoid making midchest incisions.
• Incisions follow skin crease where possible.
• Control of inflammatory acne.
• Prophylactic pressure garment.
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38. MANAGEMENT OF KELOID
• No single modality is best.
• Depends on age, location, size & response to previous
treatment.
• Combination therapy is advocated.
• Mainstay is triple keloidal therapy .
• Marginal excision, steroid injection and silicone gel sheeting.
• Steroid injection, pressure dressing & silicone gel.
• Excision, postop radiation & steroid injection.
• Regular followup,
– FBC+ DIFF, SEUCR, RBS, BP monitoring following high dose steroids
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45. PROGNOSIS
• The bane of keloid is reoccurrence.
• Hypertrophic scars usually regress with time or with
treatment.
• However, both may result in significant disfigurement and loss
of function.
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46. LOCAL EXPERIENCE (1yr)
• 64 new cases
• M: F= 1:2
• Ear lobe (65%), upper arm(25%), others (10%)
• Marginal excision + intralesional kenalog+ silicon gel
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47. FUTURE TRENDS
• Use of vesmeter
• Stem cell therapy
• Electrochemotherapy
• Fat grafting / lipofilling
• Role of decapentaplegic homolog(Smad)3, high mobility group
boxprotein-1, and calcimycin.
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48. CONCLUSION
• Both hypertrophic scars and keloids are aberrant proliferative
scars.
• Hypertrophic scars usually regress , with better treatment
outcome.
• At present , no single best therapy for keloid management,
and the large number of treatment options reflects this.
• Combination therapy is thus advocated.
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49. References
• Rei Ogawa: Keloid and Hypertrophic Scars Are the Result of
Chronic Inflammation in the Reticular Dermis. Int J Mol Sci.
2017 Mar; 18(3): 606.
• Ahmad S.E, Etal:Keloid Scarring: Understanding the Genetic
Basis, Advances, and Prospects. Arch Plast Surg. 2012 May;
39(3): 184–189.
• Townsend M Etal :Wound healing. Sabiston textbook of
Surgery, 20 edition,2017:pg 141-144.
• Keloid and hypertrophic scar. A lecture note delivered by Dr
Uche Achebe.
• Sriram Bhat M: Keloids. Wounds and wound healing. SRB
manual of surgery, 4th edition, 2013: pg12- 13
• emedicine.medscape.com/article/Keloids and hypertrophic
scar
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