Myopia Profile

Clinical

Do pseudophakic children need myopia control?

Posted on February 1st 2021 by Connie Gan

Sponsored by

Alcon_RGB_150-wide.jpeg

In this article:

How does the emmetropization process in childhood influence refraction shifts in pseudophakes? Do pseudophakic children need myopia control?

Do pseudophakic children need myopia control options when their myopia progresses? Removing congenital cataract does not stop the growth of axial length and corneal flattening which is typical in childhood. However, the crystalline lens thinning in phakic children, which balances with axial elongation in the emmetropization process, does not happen in pseudophakes. So is an increase in myopia considered true myopia progression?

It's an interesting conundrum that LB presented for discussion in the Myopia Profile Facebook community. Here are the details:

LB Can anyone help with information on the best myopia control options for pseudophakes? I have a 10 yr old pt (first presentation with me) phx congenital cataracts, IOL implantation at 2yrs. LE significant, pupil trauma from difficult surgery -pupilloplasty approx 2014, L amblyopia (6/9), R BCVA 6/6. No BV issues, phoria or tropia . Currently wearing PALS Her prev rx 11/2014 R -1.50, L -1.00 3/2017 R -2.50 L -1.50 5/2018 R -3.25/-0.5 L -1.50/-0.50 3/2019 R -3.75 L -1.00/-1.00 Her recent progression is less but wonder how myopic she could become so am looking at options. She is going to take some convincing to wear MFCL/ orthok and her mum is reluctant to use atropine. I have put the ideas in their minds until further discussion after researching best options. What have been others experiences and best outcomes? Thanks. LB … This young girl's mother and apparently 4 generations before her had bilateral, congenital cataracts. I am seeing the mum soon but she does not seem to have >3D of myopia judging from current specs (very subjective). Apparently dad is myopic so whether that plays a part I'm not sure.

Myopic shift or emmetropization?

CS I would be talking to a paediatric ophthalmologist as they have experience with this. Remember there will have been a bit if "crystal ball gazing" with the IOL calculation. JD I agree with CS about the 'crystal ball gazing' for the IOL. Are you able to measure the axial length? There may only be normal AL growth, therefore absence of the risks associated with longer eye lengths and the cornea will be changing too. Don't forget that in phakic children, the lens grows and counters other changes, so this part of the emmetropisation process is missing.KG Wow, interesting case LB. I agree with CS and JD on the IOL power and that this could be a complex combination between normal eye growth without normal lens compensation, and possibly some level of defocus due to lack of accommodation / altered peripheral optics of an IOL - but I have no idea what form the latter could take in a child with a growing eye. From age 5ish to 10 she’s progressed -2.25 in that eye which is a little bit more than the +1.50 to +2.00ish you might expect of emmetropization. Chat to her / a paediatric ophthalmologist and as RH said, she’ll need an add so that’s the first optical need to meet for her.MB This seems important. See reference Flitcroft et al.MB I haven't done the math on this particular case, but is the myopic shift, really "myopic" or is it just normal emmetropic growth in the absence of compensatory crystalline lens thinning?AV I would be leaning this way also, as I have had a paediatric ophthalmologists tell me he often leaves kids slightly hyperopic, to allow for axial length growth with age. But should you treat it now anyway?

When a pseudophakic child shows a myopic change in refraction, should that be attributed to the normal axial elongation that occurs with typical eye growth in childhood, or is it a myopic (pathological) elongation?

The normal, phakic eye undergoes both passive emmetropization (that which occurs with normal eye growth) and active emmetropization (that which occurs in response to visual feedback in controlling the eye growth).

Passive emmetropization happens differently in pseudophakes, as they do not have the natural crystalline lens reducing in power to compensate for overall ocular power changes due to increasing axial length. Active emmetropization in pseudophakes is affected by several factors such as age of cataract development and age of surgery, which can lead to varying visual outcomes and influences the rate of axial elongation.1 Although normal emmetropization is disrupted in a pseudophake, Flitcroft showed that they have similar rate of growth in axial length and corneal flattening to the normal childhood eye.2

Typical myopic shifts in pseudophakic children

How much axial elongation is normal in a pseudophakic child? Plager et al followed children for a minimum of 4 years post cataract surgery. They showed that children who underwent cataract removal surgery at the age of 2-3, 6-7, 8-9 and 10-15 years had a mean myopic shift of 4.60D, 2.68D, 1.25D and 0.61D respectively.3 Crouch et al reports slightly higher degrees of myopic shifts in refraction.4 Hence, it is common for an ophthalmologist to choose an IOL power that is slightly hyperopic to account for this future myopic shift in refraction, instead of aiming for postoperative emmetropia as they would for adults.

As the child in this case had cataract surgery as a 2-year-old, one would expect her to have a myopic shift in refraction of about 5D in the 5 years post-op. We have clinical data indicating that in around 4.5 years, from age 6 to age 10, this child has progressed -2.25D in the right (normally sighted) eye and not progressed at all in the left (amblyopic) eye. While this represents more of a comparative loss of hyperopia in emmetropization across this age span, without the compensatory crystalline lens flattening it could be quite normal. Getting in touch with the child's ophthalmologist to ascertain the target post-op refraction could clarify the situation.  Otherwise, obtaining axial length data may help confirm whether her axial length is within the normal range and undergoing typical elongation for her age.

Contact lenses versus spectacle lenses

PC Not had a case like this but putting aside the pseudophake aspect, I’d probably do MFSCL/OK on RE only. LE isn’t progressing and amblyopic. Atropine - I suspect some of the effect is on the lens so for a pseudophake it might not have the same effect (although it would make a good case study if can measure AL changes).RH She needs an add so a (distance-centre) MFCL seems like a good way to go to me. If she keeps progressing I would consider adding low-dose atropine. If mum is reluctant you can only inform her of the best evidence of cost vs benefits of doing something vs nothing. Good luck.RH I’ve read NaturalVue can work for presbyopes so might give decent near VA for this patient. Anyone know if the same is true of MiSight?PC I’ve tried MiSight for several young adults and they don’t seem to like the distance vision aspect. I expect presbyopes to have a similar experience.LC Both lenses aren't as clear as a spherical lens but children/teenagers/ young adults don't seem to mind I've found…

Due to the absence of a natural crystalline lens, a full near addition is necessary to allow for clear near vision. Commenters suggested prescribing multifocal or myopia controlling contact lenses, and/or low dose atropine to help in controlling myopia progression. However, the 'near add' effect provided by these contact lenses may not be as predictable as that provided by a spectacle lens add.Atropine could potentially affect near vision through pupil dilatation (it won't affect accommodation as it's not functional), but could be considered as the child is already wearing a full add to support near acuity.

Progressive or bifocal spectacle lenses are likely to be the best choice for pseudophakes of any refractive state. Given that this patient has no natural accommodation function, these spectacle lens options will give clear distance vision and a full powered, predictable add power for optimized near vision. If a myopia control effect is desired, data indicates that bifocal spectacle lenses will likely provide a strategy than progressive addition lenses - read more in Spectacle lenses for myopia control.

Does this pseudophakic child need myopia control?

Perhaps not. Her left, amblyopic eye is not progressing and her right, normally sighted eye may simply be exhibiting normal axial elongation in emmetropization. The myopic shift is then an exaggerated refractive outcome of emmetropization, due to the lack of compensating crystalline lens flattening.

This is an important case of atypical myopia where observation, especially with axial length measurement, is likely the most prudent course of management.

Take home messages:

  1. In a complex case like this with a prior history of ocular pathology and/or surgery, the refraction may not be as it seems. In childhood pseudophakia, 'myopia progression' could actually be normal emmetropization.
  2. The normal degree of change in myopic refraction differs depending on the age of cataract surgery, gender and ethnicity.1
  3. Deciding if a pseudophakic child requires myopia control can be complicated - measurement of axial length is key to determine if axial length is within the normal range and elongating at the typical rate for age. Informed consent in atypical cases of myopia is crucial. If parents and practitioner decide to proceed with myopia control, the child's need for a full add at near must be prioritized.

Meet the Authors:

About Connie Gan

Connie is a clinical optometrist from Kedah, Malaysia, who provides comprehensive vision care for children and runs the myopia management service in her clinical practice.

Read Connie's work in many of the case studies published on MyopiaProfile.com. Connie also manages our Myopia Profile and My Kids Vision Instagram and My Kids Vision Facebook platforms.

About Kimberley Ngu

Kimberley is a clinical optometrist from Perth, Australia, with experience in patient education programs, having practiced in both Australia and Singapore.

Read Kimberley's work in many of the case studies published on MyopiaProfile.com. Kimberley also manages our Myopia Profile and My Kids Vision Instagram and My Kids Vision Facebook platforms.


This content is brought to you thanks to unrestricted educational grant from

Alcon_RGB_150-wide.jpeg
Back to all articles

Enormous thanks to our visionary sponsors

Myopia Profile’s growth into a world leading platform has been made possible through the support of our visionary sponsors, who share our mission to improve children’s vision care worldwide. Click on their logos to learn about how these companies are innovating and developing resources with us to support you in managing your patients with myopia.