Derm - Introduction To Dermatology

Front 1

KOH examination

Back 1

Used to detect fungal infections of the skin. In a suspected lesion, the scales are scraped on to a glass slide. A drop of 10-20% potassium hydroxide solution is placed, which dissolves the keratin allowing better visualization of the fungal elements.

Front 2

Tzanck smear preparation

Back 2

Performed to confirm the diagnosis of a herpesvirus infection. If there is an intact blister, the blister is gently unroofed and the underside of the roof is gently scraped with a #15 scalpel blade. The material is smeared on a glass slide, air dried, then stained with any stains containing methylene blue. The presence of multinucleated epithelial cells represents herpesvirus infected keratinocytes that have coalesced.

Front 3

Mineral oil preparation

Back 3

Used to detect scabies. A suspected burrow is scraped using a #15 scalpel blade after a drop of mineral oil has been placed on the suspected burrow. Another drop of oil may be needed on the glass slide.

Front 4

Dermascopy

Back 4

Also known as epiluminescence microscopy. Has been recently developed for examining melanocytic neoplasms. The skin lesion is covered with mineral oil and a hand-held lens is used to inspect it. The fluid placed on the lesion eliminates surface reflection and renders the cornified layer translucent. This results in a more detailed visualization of morphologic structures within the epidermis, the dermo-epidermal junction, and the superficial dermis.

Front 5

Macule

Back 5

< 1 cm; flat spot that is not usually palpable, essentially a change in color. The pathologic process is subtle changes in the epidermis or in the papillary dermis.

Front 6

Patch

Back 6

> 1 cm; flat spot that is not usually palpable, essentially a change in color. The pathologic process is subtle changes in the epidermis or in the papillary dermis.

Front 7

Papule

Back 7

< 1 cm; A circumscribed solid or cystic elevation less than 1 cm. The pathologic process is usually situated in the superficial dermis and may involve the epidermis.

Front 8

Plaque

Back 8

> 1 cm; A plaque is a mesa-like (table-like) elevation. Papules may coalesce to form plaques. The pathologic process is usually in the superficial dermis.

Front 9

Nodule

Back 9

1-2 cm; Solid or cystic elevations due to a pathologic process that is usually deep in the dermis.

Front 10

Tumor

Back 10

> 2 cm; Solid or cystic elevations due to a pathologic process that is usually deep in the dermis.

Front 11

Vesicle

Back 11

< 1 cm; The origin of the blister may be subcorneal, intraepidermal (intraspinous), and subepidermal. Vesicles are usually tense.

Front 12

Bulla

Back 12

> 1 cm; The origin of the blister may be subcorneal, intraepidermal (intraspinous), and subepidermal. Bullae can be tense or flaccid depending on the age of the lesion.

Front 13

Burrow

Back 13

A burrow is formed when a tunnel is formed within the epidermis (e.g. burrow of a scabies mite).

Front 14

Cord

Back 14

A cord is usually formed when the pathologic process involves a linear or elongated structure (e.g. thrombophlebitis).

Front 15

soon

Back 15

bientôt