This case report showcases the journey of Jack* and his son Tyson, who both suffer from this condition. In fact Jack’s brother also has this eye condition. Even though many cases of keratoconus occur without a family history of the disease, it is quite clear that keratoconus is often hereditary, with a genetic cause.

*Names and personal details have been changed for this article.

IS KERATOCONUS HEREDITARY?

Jack first visited The Eye Practice in 2007, when he was 33 years old. He was previously diagnosed with fairly advanced keratoconus when he was about 22. Although glasses no longer gave Jack good vision, his Rigid Gas Permeable contact lenses were providing excellent vision.

Jack was a keen soccer player, and although his RGP contact lenses gave him clear vision, they were unstable and kept falling out during play. While RGP contact lenses are often a great choice for correcting vision in keratoconus, they are definitely not the best choice for playing many sports.

COMFORT AND CLARITY: HYBRID CONTACT LENSES

After discussing the pros and cons of various contact lens options with Jack, Jim and I fitted him into a pair of hybrid contact lenses for keratoconus. Hybrid contact lenses consist of a hard centre surrounded by a soft skirt. The hard centre gives the good vision, and the soft surround makes theses lenses very comfortable.

There is almost no risk of hybrid lenses falling out during sport.

Jack was very happy in his new hybrid lenses, and was able to continue playing sport. There was no fear of the contact lenses dislodging or falling out during play. He continued to wear his hybrid contact lenses successfully for several years.

THE EVER-CHANGING LANDSCAPE OF KERATOCONUS

By 2014 Jack’s contact lenses had become increasingly uncomfortable. A pinguecula had developed on each eye. Pingueculas are small, raised growths on the sclera (white part of the eye). They are very common and can develop with increasing age and time spent outdoors in the sun.

While these growths are not dangerous, they can become irritated and interfere with the fit of custom contact lenses for keratoconus. This is exactly what happened to Jack. The edge of the hybrid contact lens was rubbing on the pinguecula on his right eye. This was causing the eye to become irritated and making the contact lens too uncomfortable to wear. Around the same time, Jack had also started increasing his time on computer screen at work, and was suffering from dry eyes.

THE BIG GUNS FOR KERATOCONUS: SCLERAL CONTACT LENSES

In order to solve all his problems, Jack required a special contact lens. This lens would not only give him great vision and be stable for playing sport, but that would also fit onto his irregularly-shaped eye comfortably. AND at the same time, help his dry eyes.

Thanks to recent technological advances in contact lenses, we were able to design a highly customised scleral contact lens for Jack that would meet all his requirements. We took a scan of Jack’s right eye using a 3-D mapper called the sMap. This created an accurate scan of Jack’s cornea and sclera (white of his eye).

A scleral contact lens was then designed and manufactured from this scan. This resulted in a lens that perfectly moulded to the shape of Jack’s eye. It even moulded around the pinguecula, which had been causing him so much irritation. The new lens was perfectly stable on Jack’s eye, which meant that he had no trouble wearing the lens during sport. Being a hard lens, it gave Jack excellent vision.

The scleral contact lens also provided Jack’s eye with continual moisture throughout the day, which helped to relive his dry eye symptoms.

Jack found the sMap scleral contact lens so comfortable, he recently decided to order one for his left eye as well.

Can keratoconus be hereditary?

LIKE FATHER, LIKE SON: Keratoconus and hereditary factors

By 2018, Jack’s son Tyson turned 16 and was diagnosed with mild keratoconus. As this condition has a hereditary element, it’s not unusual for it to run in families. We always recommend a surface scan of the eye for family members of keratoconus patients. As it turns out Jack’s brother also has the condition. Yes, keratoconus can be hereditary as there are a number of specific genes associate with this disease.

Tyson’s keratoconus was so mild in his right eye, that he had 20/20 vision without wearing any glasses or contact lenses. His left eye on the other hand had moderate keratoconus and the vision was poor without glasses.

Because Tyson’s vision was excellent in his right eye, the poorer vision in his left eye didn’t bother him. It did not reduce his ability to work, study or play sport. It was not necessary to prescribe Tyson any glasses or contact lenses.

Because of Tyson’s young age, however, there was still a good chance that his keratoconus would continue to get worse. This disease usually continues to get worse in your teens and twenties.

STOPPING THE EYE DISEASE IN ITS TRACKS

We referred Tyson to a corneal specialist for a possible collagen cross-linking on his left eye, as well as monitoring of his right eye. This minimally-invasive surgical procedure can slow down or completely halt any worsening of keratoconus. This means that Tyson can maintain the vision he currently has, and will hopefully never need to wear contact lenses.

WHAT CAN BE DONE ABOUT KERATOCONUS IN FAMILIES?

Because keratoconus can be hereditary / genetic, parents that have keratoconus should have their children screened every year starting from around 10 – 12 years of age.
At The Eye Practice, we source specialty contact lenses from all around the world for our patients with keratoconus. Each patient’s eyes are unique and many people with keratoconus benefit from technology and designs from overseas. Keratoconus contact lenses are also designed in Australia.

Our optometrists are extremely experienced in specialty contact lenses. When choosing contact lenses for our patients we not only look at the shape of their eyes, but also take into account their work, hobbies, sports and other lifestyle factors.

RGP contact lenses for keratoconus can be a great option, as they usually provide excellent vision. However, these contact lenses are not suitable for certain activities, e.g. contact sports. They can dislodge easily and some people find them uncomfortable to wear – especially if they suffer from allergies.

Hybrid lenses are generally much more comfortable, still provide great vision, and are extremely stable for wear during sporting activities.
With time and increasing age, the sclera (white part of the eye) can develop irregularities and growths. This can make fitting custom lenses difficult. These are not usually dangerous; however, they can make contact lens wear very uncomfortable.

Thankfully, technology now exists to counteract these irregularities. Scleral contact lenses can be ordered with highly customised edges and even cut-outs. This avoids the lens rubbing on lumps and bumps on the eye.

LATEST KERATOCONUS TECHNOLOGY

Scleral mapping technology using the sMap 3D device is the latest advancement in scleral contact lenses. The Eye Practice was the first clinic in Australia to use and help develop this amazing technology.

With access to the right custom contact lens choices for keratoconus, you can maintain excellent vision, and can avoid corneal transplants.
Collagen cross-linking (CXL) is the most recent development for halting or slowing keratoconus. If this disease is diagnosed early, in the early teenage years, CXL can be performed. CXL can prevent the patient from needing to wear specialised contact lenses. Ultimately avoiding the need for corneal transplant surgery is in everyone’s best interest.

With keratoconus known to have hereditary causes, those with the disease should have their children screened from 10 years of age.

Are you failing in your keratoconus contact lenses? Are you concerned that it could be hereditary? Talk to the experts. Call The Eye Practice on (02) 9290 1899 or make an appointment online today.