British doctors have called the case of "the man that lost (part of) his mind" one of the strangest things they have ever seen.

An unidentified Northern Ireland man is a medical marvel. 

According to the British Medical Journal, the 84-year-old has been living with a huge 9 centimeter air pocket in the right frontal lobe where his brain should be.

The man was sent to hospital by his doctor after suffering multiple bad falls, dizziness, and prolonged feelings of weakness.

Shocked medics at Causeway Hospital in Coleraine, Londonderry, made the discovery after carrying out routine blood tests.

In fact, regular health checks administered to the man failed to detect anything wrong. 

When a CT of the brain revealed a large air cavity (pneumatocoele), the patient was transferred to Antrim Area Hospital for an MRI scan of his head, which also revealed a large osteoma — a benign, bone tumor.

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In his report, which includes incredulous scans of the man's brain, Dr. Finlay Brown stated that the patient was “otherwise fit and well” and had been living relatively independently at home with his family.

The patient was put under observation but refused surgery, staying in the hospital until he was discharged.

To read the full medical report, see here.