As promised, we have attempted to provide answers to the questions raised at the conference as best we can. We apologise for the delay. The Q&A and indeed any other issues raised at the conference can be followed up on our Forum which is an ideal place to get opinions from other members and sometimes qualified professionals. We encourage members to ask questions and post comments on the Forum as the database is searchable and if you look at the bottom of the page where it says ” Who is online”, you will see that there is always a number of visitors looking for information.
Here is a recording of the questions answered on the day
And here are the Questions and Answers we have compiled since
Cross-Linking (CXL)
Q1 – Is everyone eligible for CXL? Is there any indication for CXL after hydrops and resulting scarring?
A – No, cornea has to be above a certain thickness (375 microns) and there are other contraindications such as severe corneal scarring, previous herpes infection, severe dry eye. Usually not offered unless there is evidence that the keratoconus is progressing. Also, usually not offered on NHS after age of 35 years, though now evidence of progression for some later in life may affect this. A history of a previous hydrops of a corneal scar is usually a contraindication for CXL. See video on our website of talk by Marcello Leucci or summary in Summer 2022 newsletter.
Q2 – What is the success rate of CXL?
A – Refer to Moorfields results. The published Moorfields results indicate that CXL will stabilise keratoconus in more than 95% of eyes.
Q3 – Does age at which CXL is performed impact on how stable the cornea is over the long term and how does this tie in with the idea of KC stabilising in 30s?
A – It is thought that CXL will stabilise keratoconus for the years until natural stabilisation occurs with age in the mid 30’s.
Q4 – Is there an argument for those of us in High St practice with topographers to be routinely taking topography maps for young patients?
A – It would make sense for optometrists to be involved in the monitoring of young patients with keratoconus. I don’t think there are any plans at this stage for optometrists to screen the young population in general for keratoconus. It would make sense to perform scans on young patients with an increase in astigmatism.
Q5 – Interested in strategy/politics to take forward screening and early diagnosis. Are there attempts to link medical colleges and eye care?
A – As methods for screening progress there will be talks along these lines. However, there is nothing in place at this time.
Progression
Q6 – What impacts the natural rate of progression?
A – It’s not very well understood. There are several factors that are associated with progression (age of onset of keratoconus, ethnicity, allergy, eye rubbing), but how these factors affect progression is not understood. Refer to Howard Maile’s video and summary in Summer 2021 newsletter
Transplants
Q7 – How long do they last? Can they last a lifetime?
A – It varies. It also depends on the type of transplant. A partial thickness (lamellar) graft should last a lifetime. A full thickness (penetrating) transplant will last on average 20-25 years, but some don’t last so long, and some last for 40-50 years. See Australian study on transplant survival rate in Dan Gore’s talk in Winter 2019 (page 6) newsletter, but also member’s story of 40 year old graft in Summer 2021 newsletter
Q8 – Now increasing problems with light sensitivity and glare in eye with 12 yr old graft – suggestions?
A – Sunglasses, hat or baseball cap. Experient with what works best and stick with that. There are no medical treatment for this.
Causes
Q9 – Is family history of hay fever/allergies still thought to be associated with KC?
A – Yes. Our current understanding is that there is a genetic pre-disposition to keratoconus, but that environmental factors (eye rubbing, allergy) can then effect the subsequent severity.
Q10 – Why are South Asians and Iranians more susceptible to KC? Is it lifestyle, diet, or genetic?
A – Possibly a combination of all of these. The exact cause is not known.
Q11 – Are there links between air quality and anti-oxidants?
A – This is not known.
Q12 – Does data that shows KC eyes are generally bigger than normal rule out eye rubbing as the main cause of KC?
A – Our recent work shows that eye rubbing has an effect on the progression of keratoconus, although it is a small effect and not the main cause or the only factor. It makes sense not you rub your eyes if you have keratoconus
Q13 – My KC has got worse since my 30s – hormones made a big difference to vision while I was pregnant.
A – There is some evidence that keratoconus can progress during pregnancy. Hormones play a role, although it is not known how this works.
Q14 – Is watching TV/computer screens a key factor?
A – There is no evidence that this affects the cornea or the risk of keratoconus.
Contact lens wear
Q15 – Why am I getting fobbed off by hospital optoms with uncomfortable rgps instead of sclerals?
A – Not all hospitals provide sclerals. You could suggest that you are referred to a centre that offers scleral lens fitting.
Q16 – Holistic research needed to manage allergy to support lens wear and issues with eye drops and contact lens solutions
A – Yes, we agree
Q17 – Alternatives for those who cannot tolerate contact lenses?
A – There are ongoing studies on the use of corneal ring implants, laser refractive surgery combined with CXL, and intraocular lens implants for individuals who cannot tolerate contact lenses. However, these options are not widely available and further studies to confirm their safety are required.
Cataracts
Q18 – When is the best time to have cataracts done?
There is no best time. It depends on how much the cataract is affecting your vision and balancing this with the small risk involved with cataract extraction. Generally, the threshold for cataract surgery is higher for people with keratoconus than for people who do not have keratoconus because the visual outcome is more difficult to predict due to the corneal distortion.
Q19 – Can they get over-ripe so opportunity is missed?
Theoretically, although this is now extremely rare with modern surgery techniques.
Q20 – What are the causes of naturally occurring cataracts?
Unfortunately, in most people, aging is by bar far the most important risk factor.