A single arm optical coherence tomography (OCT) pachymetry system and methods for measuring layers of the eye are disclosed. The system includes an artificial lens for positioning on the eye, a light source emitting a measurement light beam along an optical path posteriorly toward the cornea, and a detector receiving and measuring a combined signal of light reflections anteriorly from a plurality of reflecting surfaces associated with the eye. The reflecting surfaces include a first reflecting surface associated with the artificial lens and one or more second reflecting surfaces corresponding to corneal layers. A processor is coupled to the detector and is configured to determine a distance between two of the corneal layers from the combined signal.