Due to its microstructure, photonic crystal fibers present wavelength regions with polarization-dependent loss, an aspect not observed in conventional fibers. We include this fact in their polarization characterization. In this research, the use of polarimetric methods to two different types of large-mode-area microstructured fibers has shown that both samples exhibited elliptical birefringence with residual torsion. We present the modifications required to perform the evaluation and justify its theoretical bases.