An elderly dementia patient strangled his own penis after wrapping rubber bands around it and leaving them on for three days.
The unidentified 81-year-old had to have emergency surgery in Chicago, Illinois, after the skin on the tip of his member started to rot.
Yellow and purple patches began to appear on the shaft and base of his penis, too, due to the lack of blood supply.
Experts said the patient's penis could have fallen off if doctors hadn't removed the bands when they did.
The African-American man, whose grisly case was published in a medical journal, was originally admitted to hospital due to complications from his diabetes.
His wife turned medics' attention to the rubber bands, which she said her husband had refused to remove for between two to three days.
Doctors at the University of Chicago Medical Centre operated to prevent further degradation.
Dead tissue was removed using a hot wire and scalpels and antibacterial lotions were applied as he recovered over five days.
A catheter — a tube put through the urethra — was used to drain the urine that had built up in his bladder as he'd been unable to urinate.
An 81-year-old man with dementia strangled his own penis to death with rubber bands in Chicago, Illinois
He recovered well from the surgery but failed to return for a check-up appointment two-weeks after leaving the hospital.
The patient had originally went to hospital after suffering diabetic ketoacidosis — a potentially deadly reaction to low levels of insulin.
When doctors asked him about the rubber bands, the man appeared to be confused.