'Delay procedure' is a well known basic surgical technique used by flap surgeons to improve the blood supply to the distal part of a random skin flap. However, surgical delay is an invasive procedure and has several disadvantages. Various lasers have been used in the nonsurgical delay of random pattern cutaneous flaps. However, the ideal laser wavelength, power density, lasing pattern, and exact mechanism (s) of action have not been fully established. Some potential clinical advantages of a nonsurgical, laser-delay technique in humans are; no surgery under anesthesia, no bleeding, no risk of infection, and no wound management. The surgeon could delay the uncertain flap during an outpatient visit two weeks before the planned surgery. More then one flap can be delayed and the most suitable one can be chosen in the operation. If the delayed flap is not used for any reason, the patient will not be left with superfluous scars.

We investigated and compared the efficiency of three different laser wavelengths (585-nm, 1064-nm, and 1320-nm) and two different lasing patterns (longitudinal borders of the virtual flap only, and full surface of the virtual flap) to conventional surgery in the nonsurgical delay of random dorsal rat flaps. We perform i.v. fluorescein injections to observe real time perfusion characteristics of rat skin after laser therapy, microangiography to see the status of skin microvasculature at certain time points, and skin biopsies for histologic evaluation and heat shock protein detection. None of the above mentioned tests has been executed before to explain laser-assisted delay phenomenon.