Cycloplegia in myopia management: uses and alternatives

Cycloplegia is a valuable tool during clinical testing to enhance the accuracy of refraction measurements, and assists in the timely diagnosis and treatment of several ocular disorders.

Cycloplegic refraction is often considered the gold standard for determining refractive error, as the true refractive state of the eye can be masked or distorted by active accommodation. This is valuable when examining children because of their increased accommodative tone compared with adults.1 

If cycloplegia is not undertaken, practitioners may run the risk of over-minusing a child’s refractive error and obtaining an inaccurate measurement.

Beyond baseline examination, cycloplegia is indicated when the clinical picture is inconsistent or when accommodation is likely to be influencing results. These encompass common clinical scenarios including:

• Amblyopia and amblyogenic risk factors e.g. strabismus, anisometropia, or high ametropia
• Latent hyperopia
• Pseudomyopia
• Accommodative disorders e.g. insufficiency, fatigue, or spasm

Cycloplegia in the examination of myopic children allows practitioners to obtain useful clinical data, such as establishing refraction before treatment and to confirm changes in prescription.

However, it is not mandatory – cycloplegic agents may not be available in your scope of practice, may not be suitable for certain children, and may not be needed if accommodation is controlled. 

The International Myopia Institute indicates that either noncycloplegic and/or cycloplegic refraction can be performed during the standard clinical examination of myopes.3 Both techniques can be used to measure refractive error, provided that accommodation is carefully controlled. 

Cycloplegic refraction can be performed at the initial visit and at appropriate intervals thereafter (e.g. annually), as long as consistent refraction techniques are applied to ensure comparable clinical data.4 

The techniques used to measure refractive error under cycloplegia can vary. 

Cycloplegic subjective refraction provides the most accurate assessment of refractive error, as it incorporates both optics and the patient’s visual perception while keeping accommodation under control.4 

For younger myopic children, objective methods such as cycloplegic retinoscopy and cycloplegic autorefraction are often more suitable. Both these approaches yield comparable results, with a difference of no more than 0.50D from the other.5

Although the use of cycloplegia is preferred, it can be difficult for patients to undertake due to inconvenience and its impact on vision.

To obtain an accurate refraction without cycloplegia, a practical alternative is to use non-cycloplegic retinoscopy with optical fogging to relax accommodation. Retinoscopy is an accurate screening tool for evaluating refraction and amblyogenic risk in children, and can easily be undertaken using a trial frame and/or over the patient’s current correction.

In patients aged 7 to 16 years, fogging the contralateral eye by +6.00D during non-cycloplegic retinoscopy achieves a result that is only 0.30D more myopic than cycloplegic retinoscopy.6 If myopia has already been determined, the amount of fogging has a negligible effect on the final refraction, so the conventional +2.00D fogging in retinoscopy may be sufficient.7

Autorefractors are widely used as an objective method for measuring refractive error and are well-tolerated. While autorefraction provides a useful starting point for refraction, autorefractors may underestimate the level of hyperopia and overestimate myopia under non-cycloplegic conditions. 

Where available, open-field autorefractors (that allow patients to fixate on a distant real-world target) provide closer results to cycloplegic retinoscopy than closed-field devices, in children aged 6 to 11 years.8

1. Cycloplegia is useful for obtaining an accurate refraction, especially in children with amblyogenic risk, pseudomyopia, or latent hyperopia.
2. Myopia management does not require cycloplegia at every visit. Cycloplegic examination can be performed at the initial visit and on indication thereafter.
3. Accommodation can be adequately controlled without cycloplegia by using non-cycloplegic retinoscopy with fogging.