CSO MS-39: Principles and Applications

MS-39 combines a Placido disc corneal topographer and an anterior segment spectral domain optical coherence tomographer (SD-OCT). The Placido disc is used for the topography of the anterior corneal surface, and the SD-OCT system is used for the topography and tomography of the anterior segment. The broadband source is an infrared superluminescent diode emitting a radiation centered around 850 nm, which provides an axial resolution of 3.5 μm and a transversal resolution of 35 μm. Different scanning patterns are available, and the instrument can acquire sections of the anterior segment, corneal topographies and tomographies, lens biometries, and pupillographies. The IOL module is based on corneal topography and anterior segment tomography and calculates the intraocular lens power by ray tracing. This is one of the easiest and most accurate methods to achieve the correct power of the lens in eyes that underwent previous corneal refractive surgery.