For weeks, President Donald Trump has said that he received an MRI at Walter Reed National Military Medical Center in October, but when asked about the procedure by the Wall Street Journal in an interview published Thursday, Trump and his doctor said that he actually got a CT scan instead.

“It wasn’t an MRI,” Trump told the Journal. “It was less than that. It was a scan.”

Last month, Trump maintained that he got an MRI, telling reporters on Air Force One that he would “absolutely” release the results.

The White House has not specifically said why Trump received the scan. In November, Trump claimed the MRI was part of his yearly physical.

Trump’s physician, Navy Capt. Sean Barbabella told the Journal that the president had received a CT scan — not an MRI. Barbabella said Trump’s doctors initially told him they would perform either an MRI or a CT scan.

Both magnetic resonance imaging (MRI) and computed tomography (CT) scans are imaging methods used by health care professionals to look at organs and structures inside the body to help diagnose a variety of conditions. While an MRI scan uses a large magnet and radio waves to generate a picture, a CT scan uses X-rays.  

On Dec. 1, the White House released the results of Trump’s advanced imaging tests, describing them as “perfectly normal.” Barbabella said then that the imaging helps confirm Trump’s overall health and identifies any early issues before they become serious.

Barbabella told the Journal that the CT scan was done “to definitively rule out any cardiovascular issues” and showed no abnormalities.

Barbabella told ABC News in a statement on Thursday that the president remains “in exceptional health and perfectly suited to execute his duties as Commander in Chief.”

In late October, Trump first said he had an MRI as part of the “advanced imaging” tests he received at Walter Reed.

“I got an MRI. It was perfect,” Trump said at the time. “I mean, I gave you the full results. We had an MRI and the machine, you know, the whole thing, and it was perfect.”

Even though Trump said multiple times that he had received an MRI, White House press secretary Karoline Leavitt told ABC News on Thursday that Trump’s “physicians and the White House have always maintained the president received advanced imaging.”

Although the advanced imaging was taken as a preventative measure, according to the White House and Barbabella, Trump told the Wall Street Journal that he now regrets getting it done, saying in the interview that it’s being used as “ammunition” against him.

“In retrospect, it’s too bad I took it because it gave them a little ammunition. I would have been a lot better off if they didn’t, because the fact that I took it said, ‘Oh gee, is something wrong?’ Well, nothing’s wrong,” Trump said.

In his Wall Street Journal interview, Trump said that the large dose of aspirin he takes daily has caused him to bruise easily, adding that he’s refused his doctors’ advice to take a lower dose, adding that he has taken that specific aspirin for 25 years.

“They say aspirin is good for thinning out the blood, and I don’t want thick blood pouring through my heart,” Trump said told the Wall Street Journal. “I want nice, thin blood pouring through my heart. Does that make sense?”

In the Wall Street Journal article, Trump pushed back against criticism that he has struggled to keep his eyes open during several White House events, appearing to fall asleep.

“I’ll just close. It’s very relaxing to me,” Trump said to the Wall Street Journal about not falling asleep at White House events. “Sometimes they’ll take a picture of me blinking, blinking, and they’ll catch me with the blink.”

One of the most notable recent examples of this occurred during Trump’s Cabinet meeting in December and his November announcement to reduce the cost of weight-loss medication.

The Wall Street Journal reports that staff has counseled Trump to try to keep his eyes open during public events and that White House Chief of Staff Susie Wiles has urged Cabinet members to shorten their presentations.

The Administrator for the Centers for Medicare & Medicaid Services, Mehmet Oz, who was at the November event where Trump appeared to doze off, told the Journal he believes Trump became bored.