20-year-old gravure idol Hatsune Matsushima revealed on her blog that she has been undergoing medical tests to determine the cause of a recent health problem. Since about two weeks ago, she has been suffering from symptoms that suggest a vascular disorder of the brain known as Moyamoya disease.

Early on Tuesday this week, she experienced a headache accompanied by her vision turning white, and she was taken to a hospital by ambulance. Matsushima wrote in her blog that she thought she might die at the time. She was sent home the same day with an intravenous drip, but two days later she fainted in her bathroom for about 20 minutes. She was given an MRI scan that day, and she is expected to receive her results on May 20.

Matsushima's agency stated that the doctor believes it to be caused by a contraction of blood vessels in the brain. The idol will continue to receive medical attention at the hospital, though she will not be taking a break from work, which includes appearances in dramas and variety shows.