Free flap neovascularization: myth or reality?

Area of Science:

• Microsurgery
• Vascular Surgery
• Tissue Engineering

Background:

• Free flaps are crucial in reconstructive surgery, relying on vascular connections for survival.
• Understanding the long-term vascularization of free flaps is essential for optimizing surgical outcomes.
• The potential for independent vascularization across the flap inset has been a subject of investigation.

Purpose of the Study:

• To evaluate the vascular supply of free flaps several months post-surgery.
• To determine if free flaps develop independent blood flow across the flap inset.
• To assess the dependence of free flaps on their original vascular anastomoses.

Main Methods:

• Utilized a color Doppler flowmeter to assess blood flow in 17 free flaps.
• Identified arterial and venous anastomoses, flap margin vessels, and vessels across the flap inset.
• Performed manual compression of the main vascular pedicle to evaluate collateral circulation.

Main Results:

• All original arterial and venous anastomoses were patent, with no evidence of stenosis.
• No neovascularization exceeding 0.5 mm was identified across the flap inset.
• Vessels near the flap inset showed complete emptying upon pedicle compression, indicating dependence on the main supply.

Conclusions:

• Free flaps do not appear to gain significant blood supply from vessels across the flap inset.
• Free flaps remain significantly dependent on their original vascular anastomoses for long-term survival.
• This dependency highlights the critical importance of secure and patent vascular anastomoses in free flap surgery.