Diascopy

Definition

Diascopy is a diagnostic technique where pressure is applied to the skin using a transparent object to observe changes in color. It helps differentiate between vascular and non-vascular lesions.

5 Must Know Facts For Your Next Test

1. Diascopy is used to assess blanching of the skin, which can indicate the presence of blood within vessels.
2. The procedure involves pressing a glass slide against the skin to determine if redness is due to capillary dilation or extravasation.
3. Blanching during diascopy suggests that the redness is caused by hyperemia rather than hemorrhage.
4. Diascopy can help diagnose conditions like petechiae, purpura, and erythema nodosum.
5. The technique is particularly useful in assessing inflammatory and infectious conditions affecting the integumentary system.

Review Questions

• What does diascopy help differentiate between when assessing skin lesions?
• Why does the skin blanch during diascopy?
• In what types of conditions can diascopy be especially useful for diagnosis?

Related terms

Blanching: The whitening of the skin when pressure is applied, indicating normal blood flow.

Erythema: Redness of the skin caused by increased blood flow in superficial capillaries.

Petechiae: Small red or purple spots on the body caused by minor hemorrhage (broken capillary blood vessels).