Skin terminologies.ppt
- 2. Common Terminologies • Dermatosis / Dermatoses : Any cutaneous lesion or group of lesions. Any Skin Disease • Genodermatoses : Hereditary skin disorders, many of which also accompanied by various systemic manifestations of different altered enzyme functions. • Genokeratoses : Hereditary skin diseases which are characterized particularly by alterations in normal keratinization process
- 3. • Dermatitis : Inflammation of skin. Not a final diagnosis • Lesion : An area of altered skin. It can be solitary or multiple • Rash: Widespread eruption of lesions
- 5. Distribution of Lesions • Acral : Affecting the distal portions (extremities) of limbs (hand & foot) and head (ears, nose, etc) • Dermatomal: Corresponding with nerve root distribution • Seborrheic : areas of skin which have a tendency to be oily. Such as scalp, behined ears, eyebrows, nasolabial fold, etc • Intertriginous : Area is where two skin areas may touch or rub together. Examples of intertriginous areas are the axilla of the arm, the anogenital region, between digits, etc
- 7. Shape of Lesions • Annular: Lesions grouped in a circle • Linear / Striate: Line like • Reticular : Net-like • Serpiginous : skin lesion having a wavy margin / Snake like appearance • Discoid / Nummular : Round or Coin shaped • Herpetiform: Grouped or clustered vesicles or ulcers • Morbilliform : A rash which looks like measles • Target / Iris lesion: lesions having concentric rings like a bulls-eye or archery target
- 8. Annular: Lesions grouped in a circle
- 10. Serpiginous : lesion having a wavy margin
- 11. Discoid / Nummular : Round or Coin shaped
- 12. Herpetiform: Grouped or clustered vesicles or ulcers
- 13. Morbilliform : A rash which looks like measles
- 14. Target /Iris lesion: lesions having concentric rings like a bulls-eye
- 15. Colour of Lesions • Erythema : red skin due to increased blood supply and it will blanch on pressure. • Purpura : is bleeding into the skin • Petechiae : Pin-point small red or purple spot caused by bleeding into the skin. • Ecchymoses : a subcutaneous spot of bleeding with diameter larger than 1 centimeter • Hyperpigmentation : may be caused by excess of melanin or haemosiderin deposits that result in skin colour that is darker than normal. • Hypopigmentation : is loss of normal melanin and results in skin colour that is paler than normal but not completely white.
- 16. Erythema : red skin due to increased blood supply
- 17. Petechiae
- 18. Ecchymoses
- 20. Hypopigmentation
- 21. DiscreteLesions • Macule : Circumscribed alterations in skin color less than 1 to 1.5 cm in diameter. The skin surface is neither elevated or depressed in relation to the surrounding skin . The surface is smooth. • Patch : A large area of colour change (> 2cms) with a smooth surface. • Papule : A small raised or elevated palpable lesion less than 0.5 cm in diameter. • Plaque : is a raised or elevated palpable flat lesion greater than 0.5 cm in diameter. • Nodule : A swelling or enlargement of a papule in three dimensions (height, width and length).
- 22. Macule
- 24. Papule
- 25. Plaque
- 26. Nodule
- 27. • Blister: Accumulation of fluid either within or below the epidermis and mucous membrane • Vesicle: Elevated fluid filled blister containing clear fluid that is lesser than 0.5 cm in diameter • Bulla: Elevated fluid filled blister containing clear fluid that is greater than 0.5 cm in diameter • Pustule : Circumscribed elevation of the skin that contains a purulent exudate that may be white, yellow, or greenish- yellow in color. • Abscess : A localized collection of pus in a cavity formed by disintegration or necrosis of tissue.
- 28. Vesicle
- 29. Bulla
- 31. Epidermal Changes • Desquamation / Exfoliation: skin coming off in scales. • Psoriasiform - large white or silver flakes, as in psoriasis. • Pityriasiform - a branny powdery scale. • Lichenoid - when scale is tightly adherent to the surface of the skin. • Keratotic - horny scale with plenty of keratin. • Maceration - moist peeling skin. • Verrucous - resembling a wart.
- 32. Desquamation
- 33. Psoriasiform
- 34. Pityriasiform
- 35. Verrucous
- 36. Secondary Changes • Crusting: Crusts result when serum, blood, or purulent exudate dries and it is a hallmark of pyogenic infection. Crusts are yellow when they have arisen from dried serum; green or yellow-green when formed from purulent exudate; and brown or dark red when formed from blood. • Ulcer : A discontinuity in skin or mucous membrane with complete loss of epidermis and possible loss of dermis • Erosion : a loss of epidermis above the basal layer, leaving denuded surface. • Fissure : Thin crack within the epithelium or linear cleavages or gaps in the skin surface
- 37. Crusting
- 38. Ulcer
- 39. Erosion
- 40. Fissure
- 41. • Atrophy : Atrophy of the skin may involve the epidermis, or the dermis, or both. It is the thinning process associated with decreased number of cutaneous cells. • Cicatrix (scar) : variety of dermal and epidermal changes associated with wound healing and resulting in fibrous tissue replacing normal tissue in the affected areas. • Telangiectasis : localized group of superficial distended blood capillary vessels. It appears as a red spot that may look spidery and that blanches when pressure is applied
- 42. Cicatrix
- 43. Telangiectasis
- 44. Histological Changes • Acantholysis: loss of intercellular connections (desmosomes) between keratinocytes • Acanthosis: thickening of prickle cell layer in epithelium. • Basophilic degeneration: age and sunlight related changes of collagen and elastic fibers • Spongiosis: intraepidermal edema, causing splaying apart of keratinocytes in stratum spinosum (resembling a sponge), vesicles due to shearing of desmosomes • Dyskeratosis : abnormal, premature keratinization of keratinocytes below granular cell layer; often have brightly eosinophilic cytoplasm • Hyperkeratosis: thickened cornified layer
- 45. Acantholysis
- 46. Acanthosis
- 48. Spongiosis
- 49. Dyskeratosis
- 50. Hyperkeratosis