Medics were astonished to discover that 27 contact lenses had buried themselves behind the eye of a woman who was due to have cataract surgery.
The pensioner, 67, was completely unaware that the lenses were missing and told surgeons she thought the discomfort was simply down to her old age, reports the Daily Mail.
Medics initially found 17 contact lenses - but then discovered a further 10 on a second inspection.
"None of us has ever seen this before," Specialist trainee ophthalmologist, Rupal Morjaria, told Optometry Today.
'It was such a large mass. All the 17 contact lenses were stuck together.
"We were really surprised that the patient didn't notice it because it would cause quite a lot of irritation while it was sitting there."
The woman had worn disposable contact lenses for the past 35 years but had not attended regular optometrist appointments.
Unfortunately for the pensioner her cataract operation had to be postponed following the surprising discovery.
Ms Morjaria emphasised that publishing the report was important for raising awareness among the general public.
Surprisingly, the patient had not reported any symptoms of the missing contact lenses.
Because the lenses were behind the woman's eye for so long, it meant a large amount of bacteria had built up around her conjunctiva.
The case, which took place last November, was published in the British Medical Journal.
It had previously been thought not possible to retain so many contact lenses without more severe symptoms.