Observations on dermal blood flow as reflected by technetium-99m pertechnetate clearance

Area of Science:

• Nuclear Medicine
• Dermatology
• Vascular Biology

Background:

• Assessing skin blood flow is crucial for various clinical scenarios.
• Current methods for quantifying dermal blood flow have limitations.

Purpose of the Study:

• To evaluate the utility of Technetium-99m (99mTc) isotope clearance for measuring dermal blood flow.
• To investigate the impact of lignocaine and adrenaline on skin blood flow.
• To assess the technique's applicability in clinical settings like ischaemic skin and skin grafts.

Main Methods:

• Intradermal injections of Technetium-99m (99mTc) were administered to human volunteers.
• Clearance rates were measured in normal skin, skin treated with lignocaine or lignocaine/adrenaline, ischaemic skin, and healed skin grafts.
• Isotope clearance was also assessed in pedicle skin flaps before and after axial pedicle clamping.

Main Results:

• Adrenaline significantly reduced the clearance rate of 99mTc, eliminating the fast clearance component.
• Ischaemic skin and healed split thickness skin grafts showed a similar absence of the fast clearance component.
• Clearance ratios in pedicle skin flaps indicated the degree of neovascularization.

Conclusions:

• Technetium-99m (99mTc) isotope clearance is a safe, easy-to-use technique for quantifying dermal blood flow changes.
• The method is valuable in diverse clinical situations, including assessment of skin flaps and grafts.
• Further research is warranted to explore additional applications of this technique.