Prescribing orthokeratology lenses has always been an enjoyable part of my specialty lens practice. For my patients, though, the early days of my practice weren’t quite as pleasant. Fifteen years ago, diagnostic lenses were used to assess appropriate corneal alignment, and sometimes a few lenses were placed on eye before the correct lens was determined. Now, initial visits are spent getting to know new patients and their families and creating excitement around the orthokeratology process.

The first major shift in my prescribing of orthokeratology lenses was utilizing topography scans for more than just keratometry values. Switching from axial maps to elevation data assisted in determining the need for toric peripheral curves, and the ability to accurately measure corneal size allowed for specific lens diameter selection. Corneal topography continues to be an essential tool in the initial and follow-up assessments to ensure accurate corneal molding is taking place and to measure the position and size of the treatment zone as well as the amount of correction.

Corneal topography has become even more valuable with the development of orthokeratology design platforms. These programs use more than the standard keratometry and refraction values to build an orthokeratology lens. Additional parameters such as corneal eccentricity and patient age are included to design a custom orthokeratology lens in seconds, complete with the appropriate sagittal depth and treatment zone size. Sagittal depth is a parameter commonly used in scleral lens design; however, it is just as important in orthokeratology. Corneas with the same keratometry values but different eccentricities will have different sagittal depths and require customized orthokeratology lenses for a safe and effective treatment.

Topography and lens design platforms are useful not only for the initial patient assessments but also as excellent tools to assist during orthokeratology troubleshooting. During a follow-up visit, a topography scan is performed first, and the examination can be streamlined and focused based on its results. Tangential maps can assist providers in understanding the overnight lens position, treatment zone size, and peripheral curve alignment. Comparison maps can be created to assess the amount of myopic correction generated by lens wear and whether that correction is centered on the patient’s visual axis.

For example, when a patient’s follow-up refraction yields residual myopia and appears undertreated, the practitioner must decide which of the many options are needed to improve patient results. Changes could include a base curve or sagittal depth adjustment or a change to the diameter or treatment zone size. Without topography, troubleshooting orthokeratology is significantly more challenging.

With the knowledge gained from topography scans, accurate and predictable lens adjustments and orders can be made with a few clicks in the design platform, saving the provider time during the lens order process and future follow-up visits. Design platforms can offer a wealth of information to support the provider and office team. Many platforms can simulate tear layer thickness and predict fluorescein patterns to optimize the provider’s assessments of treatment zones, lens depths, and peripheral curve systems. The office team can support the provider through the portal, with access to manufacturing and shipping times as well as lens reorders when needed by the patient.

Platforms have historically been used by experienced orthokeratology practitioners, as these providers are usually making design change decisions more confidently without the assistance of consultation. However, new platform options can also suggest lens modifications to novice orthokeratology providers with the input of manifest and over-refraction findings along with an uploaded post-treatment topography.

With the assistance of technology, providers of all experience levels can confidently move forward with lens adjustments in many cases, when supported by platform algorithms.

Brooke M. Messer, OD, FSLS, FAAO practices at Vance Thompson Vision in West Fargo, ND. She is also a fellow of the American Academy of Optometry. She has received remuneration from Bausch + Lomb SVP, Glaukos, and Heidelberg.

 This editorial content was supported via unrestricted sponsorship