Validation of Innovative Scheimpflug Topography Derived RGP Contact Lens Designs In Optometry Network

Inclusion Criteria: * \- WP1: * (a) Presence of keratoconus in either eye * (b) Currently using a rigid gas permeable contact lens correction * (c) Male or female, aged 18 years or older * (d) The absence of significant media opacities * (e) No ocular pathology other than keratoconus * (f) Ability to understand nature/purpose of the study and to provide informed consent * (g) Ability to follow instructions and complete the study * (h) Ability to speak English * WP2: * (a) Presence of keratoconus in both eyes * (b) Male or female, aged 18 years or older * (c) The absence of significant media opacities * (d) No ocular pathology other than keratoconus * (e) Ability to understand nature/purpose of the study and to provide informed consent * (f) Ability to follow instructions and complete the study * (g) Ability to speak English * WP3: * (a) Optometrist, dispensing optician or ophthalmologist registered with the General Optical Council * (b) Works within contact lens service at Moorfields Eye Hospital * (c) Ability to understand nature/purpose of the study and to provide informed consent * (d) Ability to follow instructions and complete the study * (e) Ability to speak English . Exclusion Criteria: * \- WP1: * (a) Any systemic disease likely to affect visual performance * (b) Any ocular disease that may affect visual performance, other than keratoconus * (c) Hearing impairment sufficient to interfere with hearing instructions * (d) Poor understanding of English language and/or alphabet * (e) Any condition which, in the investigator's opinion, would conflict or otherwise prevent the participant from * complying with the required procedures, schedule, or other study conduct. * (f) Not currently using a rigid gas permeable contact lens or a contraindication to this * (g) A history of corneal graft surgery (keratoplasty) in the eye under investigation. * (h) A recent history (in preceding 12 months) of corneal abrasions in the designated study eye * (i) A recent history (in preceding 1 month) of corneal cross linking for keratoconus * WP2: * (a) Any systemic disease likely to affect visual performance * (b) Any ocular disease that may affect visual performance, other than keratoconus * (c) Hearing impairment sufficient to interfere with hearing instructions * (d) Poor understanding of English language and/or alphabet * (e) Any condition which, in the investigator's opinion, would conflict or otherwise prevent the participant from * complying with the required procedures, schedule, or other study conduct. * (f) A contraindication to rigid gas permeable contact lens wear * (g) A history of corneal graft surgery (keratoplasty) in the eye under investigation. * (h) A recent history (in preceding 12 months) of corneal abrasions in the either eye * (i) A recent history (in preceding 1 month) of corneal cross linking for keratoconus * WP3: * (a) An optometrist dispensing optician or ophthalmologist not fully registered with the General Optical Council (e.g., a pre-registration optometrist) * (b) Hearing impairment sufficient to interfere with hearing instructions * (c) Poor understanding of English language and/or alphabet * (d) Any condition which, in the investigator's opinion, would conflict or otherwise prevent the participant from complying with the required procedures, schedule, or other study conduct.