Introduction

Advancements in instrumentation have enabled clinicians to obtain more accurate and reliable clinical data to guide myopia management and provide individualized evidence-based care for patients.This IMI paper summarizes clinical best practices for the use of instrumentation to assess optical and structural aspects of the eye.

Optical Assessment:

Refractive Error: Cycloplegic subjective refraction remains the gold standard for determining refractive error. However, when this is not feasible, cycloplegic retinoscopy and cycloplegic autorefraction are the most accurate alternatives.

Non-cycloplegic refractive error may be on average 0.6D–0.8D more myopic than cycloplegic results in myopic children. This difference is larger and more variable for hyperopic and emmetropic children (1.80D ± 1.11D and 1.26D ± 0.93D, respectively). Cycloplegia should always be included in the clinical workup for patients up to 20 years old; beyond age 20 the difference between cycloplegic and non-cycloplegic refractive errors falls below 0.25D

In the absence of cycloplegia, open-field autorefractors provide the results closest to cycloplegic retinoscopy. Measuring relative peripheral refraction may offer insight into identifying individuals at risk for developing myopia or for gauging their potential responsiveness to myopia control treatments, though further research is needed to confirm its predictive value.

Corneal measurements: Corneal topography provides detailed mapping of the corneal front surface and plays a crucial role in evaluating patients’ suitability for contact lens fitting, in particular orthokeratology treatment. Corneal tomography involves the 3D reconstruction of the entire cornea, including both anterior and posterior surfaces, and corneal thickness. Some corneal topographers offer supplementary functions for evaluating the stability of the tear film which is valuable in managing patient comfort, as dry eye is commonly observed in individuals with myopia.

Pupillometry: Although pupil diameter can be measured using basic clinical tools such as rulers or pupil gauge cards, automated pupillometry offers greater precision and repeatability. This capability is available in handheld and mobile devices, as well as in multifunction instruments that also perform autorefraction and keratometry. Pupil size measurement is a useful consideration in clinical myopia management, particularly when prescribing optical interventions such as orthokeratology and dual-focus soft contact lenses. These lenses depend on the alignment of their optical treatment zones with the pupil to deliver effective myopic defocus. Pupil size can influence image quality, treatment efficacy, and visual symptoms. Assessing pupil size can assist with lens selection, assessing centration, and troubleshooting complaints related to ghosting, halos, or suboptimal control.

Structural Assessment:

Axial length biometry: As a critical biomarker for myopia management, axial length biometry is particularly valuable in regions where eye care practitioners may be unable to use cycloplegia. Non-invasive methods using partial coherence interferometry, optical low coherence reflectometry and optical coherence tomography provide accurate and repeatable measurements for tracking axial elongation. Support software that compares patient data to normative growth curves, tailored by patient-specific factors like age, sex and ethnicity, can guide individual patient management.

Posterior Segment Imaging: Imaging options such as fundus photography and optical coherence tomography (OCT) scanning are valuable for detecting and monitoring myopia-related pathology. Although choroidal thickness can be measured using OCT, and may provide insight into myopia progression, its role in routine clinical management has yet to be clearly defined.

Personalised care

Early identification of individuals at risk of myopia is a key component of personalized care. Risk assessment before onset includes evaluating family history, near work, outdoor exposure, and quantifiable measures such as refractive error and axial length. Noninvasive methods and predictive algorithms based on optical biometry and normative axial length data now support individualized risk profiling. Clinicians can further personalize care by conducting regular comprehensive assessments and integrating these predictive factors to support early diagnosis and management. Although AI-based models show promise, they require training on large, diverse datasets and further clinical validation before widespread adoption.

Conclusion

Modern instrumentation plays a critical role across the continuum of myopia management, from identifying at-risk individuals before onset, through progression and active treatment, to long-term stabilization in adulthood. Advances in diagnostic tools and software support more accurate assessments and enable personalized, evidence-based care, enhancing clinical decision-making at each stage in the management of myopia.