Microsurgery refers to the use of a microscope and fine instruments to perform very precise, intricate surgery. The advent of microsurgery has enhanced the reconstructive options available to surgeons to treat patients with injuries from trauma, cancer defects, breast cancer reconstruction, or congenital problems. With the microscope's powerful magnification, specialized tools, and stitches thinner than human hair, microsurgery may be used to re-establish blood flow in small blood vessels and repair important nerves. It can have profoundly positive impact on a patient's form and function after a potentially devastating injury or cancer diagnosis.
Common uses for microsurgery include replantation of amputated digits or limbs, nerve repair, toe-to-hand transplantation (e.g. transferring a toe to make a new thumb), and "free" flaps. In recent years, it has even been used to perform face and hand transplantations from organ donors.
A "free" flap is a particular kind of microsurgery that involves borrowing tissue (the "flap") from elsewhere in the body (the "donor site") and transplanting it to a recipient area to reconstruct a defect or hole, usually caused by cancer removal or trauma (e.g. exposed bone in the leg). For a free flap to be viable, microsurgery is required to connect the blood vessels of the flap to the local blood vessels, which reestablishes circulation to the transplanted tissue.
Common examples of when free flaps are used include breast cancer reconstruction, lower leg salvage surgery, and head and neck cancer reconstruction. The use of free flaps has allowed surgeons to reconstruct defects which prior to the advent of microsurgery would otherwise be life or limb-threatening.
Microsurgery may not always be an option for every patient. They are often long, technically challenging procedures. A patient's diagnosis, past medical history, and a surgeon's comfort and expertise may determine if microsurgery is a reconstructive option. For example, microsurgery tends to be less successful and riskier in patients with other major health problems or who smoke.