Political junkies and/or fashonistas may have noticed that Secretary of State Hillary Clinton was wearing glasses during her Wednesday testimony for the Senate Foreign Relations Committee. So what’s the story behind Clinton’s new accessory?

It appears that Clinton is wearing the glasses to correct a case of double vision that the secretary of state developed after she suffered a concussion in December. The New York Daily News confirmed that the glasses she is wearing include a Fresnel prism, which is used in cases of double vision.

In December, Clinton suffered a potentially serious blood clot followed by a concussion. The combination of health issues seems to have left her requiring the glasses for some time.

Clinton’s spokesman Philippe Reines told New York magazine that she will "be wearing these glasses instead of her contacts for a period of time because of lingering issues stemming from her concussion."

"With them on she sees just fine," Reines said. "In fact, she got a kick out of [New York magazine’s] seven expressions and captions when she saw them crystal clear."

Clinton first wore her glasses while testifying about the Sept. 11, 2012, attacks on the American embassy in Benghazi, Libya. The secretary of state got particularly angry during the testimony when Sen. Ron Johnson, R-Wisc., began questioning the Department of State’s initial accounts of the attack.

"With all due respect, the fact is we had four dead Americans," Clinton said to Johnson, according to the Huffington Post. "Was it because of a protest or was it because of guys out for a walk last night who decided to kill some Americans? What difference at this point does it make? It is our job to figure out what happened and do everything we can to prevent it from ever happening again, Senator."

"Honestly, I will do my best to answer your questions about this, but the fact is people were trying their best in real time to get to the best information," she said.

Clinton is expected to step down from her secretary of state position sometime next week and make a return to private life. Several reports suggest she is also considering a bid for the presidency in 2016.