Angiogenesis, the formation of new blood vessels, is essential to a va
riety of normal and pathologic processes such as wound healing and tum
or growth. In microsurgery the development of new vessels between the
transferred tissue and the recipient bed is critical to the final outc
ome of the reconstruction. Several experimental models have been previ
ously developed to study angiogenesis and the effect that new substanc
es have on regulating this process, but they lack the ability to make
quantitative measurements. Therefore, we have developed an animal mode
l using the homozygous (hr/hr) hairless mouse ear; by using intravital
microscopy and computer-assisted analysis, angiogenesis can be quanti
tatively measured. Using this model we showed that basic fibroblast gr
owth factor and transforming growth factor beta significantly increase
d total vessel length by 32% and 63%, respectively, during 20 days fol
lowing subcutaneous injection. In this paper the importance of angioge
nesis research to reconstructive microsurgery is presented and discuss
ed.