Children are our future: It is critical that we do our very best to protect their most valuable sense – vision – when prescribing eyewear. Children can suffer from a variety of vision problems, like congenital cataracts, strabismus and other refractive issues, some of which may arise at a very young age, while others develop as they age and grow.
Although more complex cases of spectacle prescribing for children may be handled by optometrists who specialise in behavioural optometry, modern trends and shopping malls mean that children are increasingly venturing into more commercial settings for eye care and to source their eyewear.
The frames and lenses we prescribe for children are especially important as they will impact their acceptance of the need to wear glasses and their ability to concentrate in class and participate socially. For children who need high plus or minus lenses, high index and aspheric options can help lighten the load, aid correct centration and provide improved cosmesis.
Materials and Coatings
Safety is critical and specialised safety materials with high impact resistance are especially important to protect children’s eyes during the rough and tumble of everyday life. So too, is UV protection.
safety materials with high impact resistance are especially important to protect children’s eyes during the rough and tumble of everyday life
There’s often debate as to whether anti-reflection multicoats should be applied, taking into account that these can be damaged from rough handling and show up greasy deposits, fingerprints, food residues and the like.
Lenses to Manage Developing Visual Problems
As children reach school age, more complex visual problems may emerge. We may need to prescribe Irlen tints for learning problems or corrections for low degrees of hyperopia, where accommodative-convergence issues arise. In accommodative esotropia, usually arising from higher degrees of hyperopia, we again need to consider high index aspheric lenses. In some cases, bifocal or progressive lenses are indicated.
Prism corrections – both horizontal and vertical – and even at times oblique prisms, may be necessary for some forms of strabismus. Low degrees of prism can be built into the lenses. We may succeed with higher degrees of prism in children than in adults, due to the smaller lens diameters required. For higher prism requirements and those that may vary rapidly over time, a stick on Fresnel prism is a potential option.
Myopia Control
As we know, we are in the midst of a growing myopia epidemic worldwide. This means we are seeing increasing numbers of children requiring myopia correction or myopia control lenses.
Respected optometrist Tim Thurn, Director of Professional Services at Essilor NZ says although myopia control can be daunting for practitioners and parents alike, spectacle lenses are an easy first step for parents to help their children.
Spectacle lenses are also key in supporting more complex therapies. Low dose atropine, for example, reduces accommodation by around two to three dioptres, which may mean lenses that support near vision are required. Likewise in patients being treated with orthoK or soft multifocal contact lenses, their spectacle correction should be part of their myopia control plan.
Describing Essilor Myopilux lenses for myopia control, Mr. Thurn said, “Myopilux Plus lenses were born out of the data from the COMET study. This short-channel progressive lens is suited to esophoric patients with a lag of accommodation >0.40D. Being a short progression, the wearer has greater control of the near power. A +2.00D addition is recommended but a +1.50D is also available.”
Of Myopilux Max lenses, he said, “In a 2014 paper, Cheng, Schmid & Drobe explained the impact of using a prism controlled executive bifocal. It was found to provide positive results for all myopic patients – regardless of their phoria – but especially if their myopia is progressing at >0.50D/yr. The lens incorporates 2-prism dioptres base-in, for each eye and comes with a +2.00D addition.”
Zeiss MyoVision lenses have also been shown to slow down progression of myopia in children. The specialty single vision lens with peripheral vision management was shown to slow down progression of myopia by 30 per cent over 12 months, in randomly selected six to 12 year old children with parental myopia.1 Additionally, according to Dr. Saulius Varnas, Principal Scientist and a lens development and technology specialist with the Zeiss Vision Care Business Group, “A Synchrony MC progressive lens aims to reduce accommodative lag during near vision. Clinical trials demonstrated myopia progression retardation of 25 per cent over 18 months2 and 21 per cent over two years3 respectively.”
Supporting OrthoK
Many patients’ prescribed myopia-controlling soft lenses or overnight orthokeratology (orthoK) will need to have plano sunglasses. Of course this also applies to non-spectacle wearing emmetropes, which makes a choice of quality children’s sunglasses – covering a range of budgets – worth keeping in stock. Patients on atropine myopia therapy may also be more photophobic. Some may require occupational near prescriptions, progressives and bifocals to compensate for their reduced accommodation, especially for highly demanding near work, gaming, digital devices, reading, computer work, study and exam times. Again we may consider specialised lenses such as degressive/shift lenses, progressives or bifocal lens designs.
We should also consider selective blue blocking filters for some of these activities. Use the mivision online search to find a variety of articles that cover such ‘blue blocking’ and ‘occupational’ lenses, for more detailed information.
The YouTube video discussion ‘myopia musings #3’ is well worth searching for additional information. It covers aspects of progressives, bifocals, myopia control, esophoria, prism and much else that is too detailed to mention here. The video also dovetails nicely with mivision’s myopia issue this month and Mr. Thurn’s insights.
In the meantime take a look at the following lens listings to find out about some of the options available.
Lenses to Support Developing Eyes
Bonastar
Bonastar’s 1.74 blueEase (UV3G) lens features advanced UV+420 cut technology, a new hyper index lens that filters out UVA, UVB, and high energy visible light (HEV light) of 400nm–420nm. It’s light and thin for comfort and has stability on the face.
Contact: Bonastar (AUS) 02 9310 1688
Essilor
Airwear Transitions combined with Crizal UV is impact resistant and preserves kids’ eyes by blocking 100 per cent UV (eSPF 25) and a minimum 85 per cent blue-violet light outdoors.
According to Lakkis & Weidemann (CXO 2006), 88 per cent of 10–15 year olds preferred Transitions to clear lenses.
Contact: Essilor Account Manager
Opticare
The ClearPro Relax range reduces myopia progression in young myopes and provides relief for young hyperopes and emmetropes who experience eye strain and visual fatigue when reading, using the computer and performing other near related tasks.
Instyle Kids lenses protect children’s eyes when they’re playing, and help improve reading, writing and completing homework.
Exclusive to Opticare, available as part of a frame+fit package and can be ordered on consignment.
Contact: Opticare 1800 251 852
Rodenstock
Mono Plus 2 is a full back surface digital design single vision lens with a power boost and optimised using Listings law for eye rotation and EyeModel to calculate near script. It provides relaxed, fatigue-free vision at near – particularly when using digital devices, and sharp, high-contrast vision right up to the rim of the frame.
When combined with Solitaire Protect Balance 2 coating, Mono Plus 2 increases well-being and a balanced biorhythm.
Contact: Rodenstock Account Manager
Transitions
Transitions lenses filter harmful blue light indoors and outdoors and block 100 per cent UVA and UVB rays. They seamlessly adapt to provide the perfect tint in any light, and reduce eye fatigue and eye strain. According to the company, studies indicate 98 per cent of parents are likely to select photochromic lenses over clear lenses for their children in the future. Available in impact resistant Trivex and polycarbonate materials for maximum safety.
Contact: Transitions Account Manager
References
1. Sankaridurg, P., Donovan, L., Varnas, S., Ho., A., Chen, X., Martinez, A., Fisher, S., Lin, Z., Smith III, E.L., Ge, J. & Holden, B.A. (2010). Spectacle Lenses Designed to Reduce Progression of Myopia: 12-Month Results, Optom. Vis. Sci., 87(9), pp. 631 – 641.
2. Hasebe, S., Ohtsuki, H., Nonaka, T., Nakatsuka, C., Miyata, M., Hamasaki, I., Kimura, S. (2008). Effect of progressive addition lenses on myopia progression in Japanese children: a prospective, randomized, double-masked, cross over trial. Invest. Ophthalmol. Vis. Sci., 49(7), 2781 – 2789.
3. Yang, Z., Lan, W., Ge, J., Liu, W., Chen, X., Chen, L., Yu, M. (2009). The effectiveness of progressive addition lenses on the progression of myopia in Chinese children. Ophthalmic Physiol. Opt., 29(1), 41 – 48.
