Keratoconus in the family: should your kids be scanned?

If you have keratoconus, should your children have a corneal map?

If you have keratoconus, sooner or later you ask the obvious question: what about my kids? A study published in International Ophthalmology in 2026 looked at exactly this group. Researchers in Turkey scanned the corneas of children and young adults whose parent has keratoconus, none of whom had noticed any problem with their eyes. We have read the full paper, and this post walks through what it did, what it found and how far you can lean on it.

What the study did

This was a cross-sectional study at a single specialist cornea department. Cross-sectional means each person was examined once, with no follow-up. The team screened 56 offspring of patients being followed for keratoconus, and compared them with 60 controls of similar age and sex who had no family history of the condition. The controls were people attending the same department for a contact lens evaluation.

Everyone had a full eye examination and a scan on a Pentacam HR, a rotating camera that builds a three-dimensional map of the front and back surfaces of the cornea and its thickness (corneal tomography). The same instrument also measures densitometry, which is how much light the corneal tissue scatters. One eye per person was chosen at random for the analysis, and a second researcher who did not know which group each scan belonged to checked the data quality.

What it found

Some children already had keratoconus

Keratoconus was identified in 8 of the 56 offspring (14.3%). Three had keratoconus visible on clinical examination in both eyes. Five had keratoconus that showed up on the corneal map only, with no signs at the microscope. Two of the eight were siblings. None of these young people had come in because of symptoms.

The authors note that earlier Turkish studies reported keratoconus in roughly 11% of first-degree relatives, so their figure sits in the same region. It is far from a certainty: most of the offspring screened in this study did not have keratoconus.

Subtle differences in the rest

The eight were then set aside, leaving 48 offspring (mean age 16.8 years) and 60 controls (mean age 18.6 years). Between these two groups:

Standard curvature readings, including the steepest point of the cornea (Kmax), were similar.
The offspring had a thinner thinnest point and more elevation on the back surface of the cornea.
Several combined indices differed, including one called Final D, which blends thickness and elevation data into a single score.
Light scatter was higher in the central 0 to 2 mm and 2 to 6 mm zones, but not further out.

All of these differences were reported at P below 0.05 after correction for the large number of comparisons. A P-value is the probability of seeing a difference this large if the two groups were really the same; below 0.05 is the usual threshold for "unlikely to be chance". The exact averages sit in the paper's tables, which we were not able to extract, so we are not quoting them here.

How well the scan separated the groups

The paper reports AUC values. AUC (area under the curve) is a score from 0.5 to 1.0 for how well a measurement sorts people into two groups, where 0.5 is no better than a coin toss and 1.0 is perfect. Final D scored 0.862 and central anterior light scatter scored 0.892. Back-surface elevation scored 0.789, with a 95% confidence interval of 0.732 to 0.854; a confidence interval is the range within which the true value plausibly lies.

One point is easy to miss. These scores describe how well the scan told children of a parent with keratoconus apart from children without that family history. They do not describe how well it predicts who will go on to develop keratoconus. The authors say so directly: their cut-off values are not diagnostic thresholds, and a single out-of-range number should not be read as disease.

What the studies can't tell us

One visit, no follow-up. Nobody was scanned again. A subtle difference on a map is not proof of future keratoconus, and this study cannot say how many of the 48, if any, will ever develop it.
Small numbers. Eight of 56 is a small count. A handful of cases either way would shift the percentage noticeably, and the paper gives no confidence interval for it.
Possible referral bias. The parents were patients at a specialist cornea department, and the paper does not describe how families were invited. Families with more severe disease, or parents already worried about a child, may be over-represented. The controls were contact lens attendees, not a random sample of the community.
Overlap. The authors acknowledge substantial overlap between the groups, with most values still inside accepted normal ranges. The light scatter differences were small.
Eye rubbing and allergy were not recorded. These are linked with keratoconus and tend to run in families too, so the study cannot separate inherited risk from shared habits. We covered that question in our post on eye rubbing, pressing and massaging.
One population. How common keratoconus is varies between countries and ethnic groups. A Turkish hospital figure may not transfer to families in New Zealand.

The study received no funding and the authors declared no competing interests.

So, should your children have a corneal map?

This paper does not settle it, but it supports a cautious yes. A corneal map is quick and non-contact, and it can show changes well before a standard sight test or a glasses prescription would raise suspicion. That matters because keratoconus tends to move faster in younger people, as we discussed in early detection of keratoconus in teenagers and in the European consensus on keratoconus in children.

The honest trade-off is that a first scan will often be normal, and sometimes it will be borderline. Borderline is not a diagnosis. In that situation the useful thing is a baseline and a repeat map over time, which is the same conclusion the authors reach: these measurements are most informative when followed longitudinally and read together.

What this means for you in Hamilton

The starting point is an optometrist with a keratoconus focus, not a surgeon. The optometrist takes the baseline map, repeats it at sensible intervals, and documents whether anything is changing. If sequential maps show progression, that is the moment for referral to an ophthalmologist, who performs corneal cross-linking. If vision later needs more than glasses can give, the same optometrist fits specialty lenses such as sclerals. For many children of a parent with keratoconus, the outcome of all this will simply be a normal map on file.

The optometrist team at Rose Optometry provides keratoconus care in Hamilton, including corneal mapping for family members. If you have keratoconus and would like your child or teenager checked, you can book a keratoconus assessment. In the meantime, the one low-cost step for the whole family is to discourage eye rubbing. The optometrists at Rose Optometry are Anjali Hira, Emilie Lawson, Jacqueline Rowe, Jagrut Lallu, Jason Shen, Jessica Wood and Stella Wong, and keratoconus care is part of their clinical practice.

Reference

Atesoglu HI, Atesoglu MT, Kızıltoprak H, Kosekahya P, Acar A, Tekin K. Tomographic and densitometric corneal alterations in asymptomatic offspring of patients with keratoconus: a Turkish cross-sectional study. International Ophthalmology. 2026;46(1):374. PMID 42702660. https://doi.org/10.1007/s10792-026-04259-5