Orthokeratology is one of the most successful methods of myopia control and is considered to achieve this by altering the peripheral refractive error in myopes. Orthokeratology: background overview and unique case studies presents case studies of myopes corrected with orthokeratology despite having high levels of astigmatism or myopia. This paper shows the changes in peripheral refractive error that take place over the course of a day and demonstrates that sometimes orthokeratology can be successful for corrections outside the standard range.