Abstract-In combination with the Perfectly Matched Layer (PML)-paradigm, eigenmode expansion techniques have become increasingly important in the analysis and design of cylindrical and planar waveguides for photonics applications. To achieve high accuracy, these techniques rely on the determination of many modes of the modal spectrum of the waveguide under consideration. In this paper we focus on the efficient computation of Transverse Magnetic (TM) and Transverse Electric (TE) polarized leaky modes for multilayered cylindrical waveguides. First, quasi-static estimates are derived for the propagation constants of these modes. Second, these estimates are used as a starting point in an advanced Newton iteration scheme after they have been subjected to an adaptive linear error correction. To prove the validity of the computation technique it is applied to technologically important cases: vertical-cavity surface-emitting lasers (VCSELs) and a monomode fiber.