A drop of blood

Patients may have the solution to persistent corneal epithelial defects already pumping around their own ­body – their serum.

A new study, published in the journal Scientific Reports, has found that eye drops containing 100% serum are safe and effective at healing this type of wound, when standard treatment has failed to work.

Human serum has a key advantage over other therapies for the corneal condition, as well as functioning as a lubricant, it contains “essential substances for the recovery of a damaged epithelium,” the authors wrote.

In the research, 101 patients were offered serum eye drops, after conventional treatments had failed to heal their corneal epithelium defect within 14 days.

The undiluted serum drops were taken from the patient’s blood or the blood of an appropriate family member. The drops, which needed to be stored in the freezer, were prescribed every hour until the defect healed.

The group’s results were compared to a control group, which had continued with the standard treatment routine. The serum promoted faster and more successful healing, with defects resolving in half the time, on average, in comparison to standard treatments.

While the use of serum was successful for many patients, the authors highlighted that: “Regarding safety issues, one patient in our series had a presumptive ocular allergy to his own serum…Moreover, the downside of using 100% serum eye drops includes patient inconvenience [over a] large volume of blood collection, the likelihood of repeated blood draws, and an economic burden on patients.”

However, they concluded that human serum “could be a therapeutic option with the potential benefits of quickly healing defects, preventing complications from unhealed ulcers, and reducing the need for invasive ocular surgical interventions, frequent patient follow-up, and hospitalisation.”