Systems and methods to treat a region of a cornea of an eye having an epithelial layer disposed over a stromal layer. The system comprises a device to map a thickness of the epithelial layer over the region of the cornea to generate a map of epithelial thickness over the region, and a laser to generate a laser beam of an ablative radiation. A movable scan component is coupled to the laser to scan the laser beam over the region. A processor system is coupled to the laser and the movable scan component, and the processor system is configured to arrange pulses of laser beam to ablate the epithelial layer of the region in response to the map of epithelial thickness.