Patients with implanted aspheric intraocular lenses (with negative aberration) have been used as a model to test the balance of corneal horizontal coma by the internal optics, and the sources of this compensation (misalignment of the fovea; tilt and decentration of the lens). Marcos et al. "Balance of corneal horizontal coma by internal optics in eyes with intraocular artificial lenses: Evidence of a passive mechanism", Vision Research 48, 70-79 (2008)