Weighing the Cornea Ectasia Risks

Many young people with corneas at risk of developing or worsening keratoconus take a cautious path in life, giving up on sports and the prospect of a professional career. According to Cosimo Mazzotta MD, PhD, such important choices should not be dictated by fear of having to deal with a curable, manageable, but still impairing condition such as severe keratoconus.

“Many patients come to my clinic with a whole [host] of concerns, asking me if they should stop doing sports, especially when weightlifting is involved,” he said.

Olympic weightlifting could be considered risky for corneal stability—particularly due to the frequent use of the Valsalva manoeuvre, a breathing technique. How this could be harmful for corneal biomechanics really depends on exercise type, intensity, duration, and recovery.

Available literature demonstrates how an isometric contraction for more than two minutes does not alter the anterior chamber depth, the central corneal thickness, or the maximum corneal curvature, Dr Mazzotta said, pointing out how important this finding is to a better understanding of corneal ectasia prevention and management.

Therefore, he said, using the Valsalva manoeuvre many times a day can still be safe, assuming some preventive measures are in place. Powerlifting, for example, does not represent a risk if spaced out with aerobic activity and appropriate set length and recovery time because a short-term effort does not impact corneal curvature. However, it would not be prudent for high-risk patients to lift more than 30% of their body weight, especially exerting this weight for more than two minutes. Exceeding limits can also be harmful, he warned, as lifting for more than four hours a day, four or five times a week can put stress on the corneal biomechanics and curvature.

These cases do not consider patients with a three- or four-degree keratoconus severity. In that case, Dr Mazzotta said, the maximum lifted weight/body weight ratio must be lowered to 20%; every prolonged isometric contraction needs at least the same recovery time—ideally, two minutes of exercise interspersed with two minutes of recovery. Moreover, patients must be frequently monitored by a specialist.

Yet high-risk athletes are not the only ones at risk. According to Dr Mazzotta, a different culprit could play a stimulating role in the onset and progression of corneal ectasias: eye-rubbing in genetically predisposed individuals. A trivial bad habit, he observed, quite common when sweat ends up in the eye, causing burning sensation and involuntary rubbing. This can trigger negative feedback that may change corneal biomechanics in time, which must be stopped as soon as possible, he emphasised.

There are other sports, however, aside from Olympic weightlifting and track and field that may represent a real threat to the progression of corneal ectasias, both aerobic and anaerobic. Full-contact sports, such as boxing and martial arts, can be devastating, he warned, especially when done without some eye protection. There is a strong correlation between ocular trauma and onset of keratoconus, he added.

Even sports featuring eye coverage can pose long-term risks. The suction effect of swim goggles can, in the long run, increase corneal curvature and corneal thinning with an increase in intraocular pressure. Dr Mazzotta advised patients with thin corneas (at high risk of ectasia) and patients with POAG to be aware of the risks and look for a more suitable pair of goggles.

He stressed prevention as the key to avoiding long-lasting dramatic consequences for the athlete’s quality of life and career. As he underlined, ophthalmology should take greater account of sports, both in prevention and research.

“Just like we carefully study pathology in clinical and surgical contexts, we should also pay close attention to sports activities. A lot of people who engage in sports, particularly on a competitive and Olympic level, are obviously young, and we should be able to give them our best and well-informed advice,” Dr Mazzotta said. “We need to solve any lack of information and dispel false myths. So, we need more research, new literature, and whatever it takes to protect the eyesight of young people who want to engage in sport and dream about a future at the Olympics.”

Cosimo Mazzotta MD, PhD, FWCRS is Professor of Ophthalmology at the University of Siena; Anterior Segment Eye Surgeon at Alta Val d’Elsa Hospital; and founder and scientific director of the Siena Crosslinking Centre of Siena, all of Italy. cgmazzotta@libero.it