Ischemic induction of neovascularization: a study by fluorometric analysis.

The dynamic process of skin flap neovascularization can be quantitated in a relatively non-invasive fashion in an "in-vivo" model using the technique of perfusion fluorometry. The extent of skin flap ischemia can be monitored, and its effect on angiogenesis rapidly determined. Evidence is presented that indicates that angiogenesis develops from a distal to proximal direction corresponding to the degree of ischemia as measured by fluorescein uptake and elimination. Furthermore, although certain proximal segments of skin flaps demonstrated no uptake or elimination, survival could still occur, indicating that neovascularization need not be complete at the time of pedicle interruption.