Clinical & Lab Aid

Question 1

Used to view degrees of elevation or depression. Done in marked room with light (casts shadow)

Answer 1

Oblique lighting

Question 2

Used to enhance contrast between circumscribed hypo pigmented/ hyper pigmented lesions & normal skin

Answer 2

Subdued lighting

Question 3

365 nm ultraviolet long-wave light, “black” light
* can pick up fluorescent pigments + subtle colour differences of melanin pigmentation
* causes some superficial lesions to fluoresce
* vitiligo presents as amelanotic
* Typically used by dermatologists (not NDs)

Answer 3

wood lamp

Question 4

Firmly pressing microscopic slide/ glass spatula over skin lesion
Examiner determined whether the red colour of a macule/ Paula is due to capillary dilation (erythema) or due to extravasation (purpura) that does not blanch

Answer 4

Diascopy

Question 5

Hand lens w/ built in lighting & magnification (10x to 30x) called a dermatoscope & allows for inspection of deeper layers of epidermis & beyond
Helpful to distinguish between a benign & malignant lesion

Answer 5

Dermoscopy (Epiluminescence microscopy)

Question 6

Used to confirm diagnosis of allergic contact sensitization & identify the agent that caused the allergic reaction

Substances to be tested are applied to the skin in shallow cups (Finn chambers), taped on the skin & left for 24-48 hrs. Contact hypersensitivity will show as papular vascular rxn that will develop within 28/72 hrs.

Answer 6

Patch Testing

Question 7

Determines type 1 allergies

A drop of solution containing small amount of allergen is placed on skin & skin is pierced through the droplet with a needle. A positiver result would be a wheal appearing within 20 minutes.

Caution: Patient needs to be under contact supervision due to possibility of anaphylaxis

Answer 7

Prick testing

Question 8

Dermatophyte/ KOH collection:
* Microscopic examination for mycelia should be made of the roofs of vesicles/ scales/ hair in dermatophytosis
* Tissue is cleared w/ 10-30% KOH and warmed gently. Hyphae & spores can then be viewed.

Microbiology (Culture & Sensitivity) & Specimen Handling Biopsy

Answer 8

Skin Scraping

Question 9

• Useful in work up of cutaneous neoplasms, pigmented lesions, inflammatory lesions & chronic skin disorders
• 3 to 4 mm punch, a small tubular knife cuts through the epidermis, dermis + subcutaneous tissue by rotating the tool

Answer 9

Punch Biopsy

Question 10

Surgical removal of a tumour & some normal tissue around it

Answer 10

Excisional Biopsy