<prompt> Aberrometer is used to measure:Endothelial countKeratometryHigher order abberationCorneal stroma  <response>: Abberrometer is used to measure higher order abberations. Corneal investigations Specular: Endothelial Count. Aberrometer : Corneal higher order abberations. Aesthesiometer: Corneal Sensations. Placido disc: Keratometryanterior surface of cornea. Pentacam Orb scan: Both anterior posterior surface of cornea. Pentacam: Investigative modality of choice to do any corneal topography, it may be keratoconus, ectasia, LASIK. Topography Corneal Topography Confocal microscopy: visualize stroma used in diagnosis of stromal dystrophies latent infections. 