Updated

Chief Justice John J. Roberts suffered what was described as a “benign, idiopathic seizure” Monday, similar to the one he suffered in 1993.

Both incidents could not be attributed a specific cause, and both seem to leave no lasting effects.

The fact that doctors couldn’t point to a specific reason that either seizure occurred is not as uncommon as one might assume, said Dr. David Langer, a neurosurgeon at St. Luke’s - Roosevelt Hospital. “The majority of seizures are caused by things that can’t be seen by an MRI.”

“There’s a whole science to what causes a seizure," he said. "There are the things you can see, and there are the things you can’t see. Basically, a seizure is an electrical discharge from abnormal cells. Sometimes in children and young adults you can see scarring. However, in the majority of people the degeneration of cellular tissue isn’t visible.”

The fact that doctors didn’t discover any indication of tumors, strokes, or infections, which are the most common seizure causes that can be seen, and that Roberts’ MRI appeared relatively normal, means:

— The cause of his seizures was not serious

— It is unlikely that he had developed a new problem since 1993, and that both seizures were of the same unknown cause

Langer also said that the duration of time between the two incidences indicated that Roberts is still capable of performing his duties. However, the next few months will be critical to see if he has another incident. That’s because the duration of time between his seizures impacts upon the ability to do his job.

Langer said, “The more repetitive seizures a person has, the more problematic they become.”

The chief justice’s prognosis is actually not bad, according to Dr. Ron Alterman, neurosurgeon and director of Functional and Restorative Surgery at Mount Sinai Hospital. “It’s better than if this were his first seizure. He has demonstrated that he will have seizures and they are not of a serious nature.”

Alterman did say that age is always a factor in any workup. In Roberts’ case, the fact that he is 52-years-old does put him at risk for certain conditions like embolic stoke in which a blood clot breaks off from the heart or the carotid artery and travels to brain. However, there is currently no indication of this.

In addition to the MRI, Roberts’ doctors undoubtedly performed a spinal tap to rule out infections like meningitis, an inflammation oft he membranes covering the brain and the spinal chord, and encephalitis, an inflammation of the brain. A spinal tap would also be used to rule out metabolic derangements like hypoglycemia and low sodium.

Roberts will probably not have to take medication, the doctors said. Anti-epileptic medications are reserved for serious repetitive seizures. However, he may have certain activities restricted as he did in 1993. At that time, his doctors temporarily restricted his diving.

This is typical, said Alterman. “Activities such as driving, diving, orflying a plane are restricted because a sudden loss of consciousnesswould pose a danger to Justice Roberts and others,” he added.

Foxnews.com health writer Maria Esposito contributed to this report

Dr. Manny Alvarez is the managing editor of health news at FOXNews.com, and is a regular medical contributor on the FOX News Channel. He is chairman of the Department of Obstetrics and Gynecology and Reproductive Science at Hackensack University Medical Center in New Jersey. Additionally, Alvarez is Adjunct Professor of Obstetrics and Gynecology at New York University School of Medicine in New York City.