"No hair, no ears, no neck." That's how one journalist described a front-page portrait of Iranian mathematician Maryam Mirzakhani that an Iranian newspaper digitally doctored to obscure her hair and skin to placate censors in the Islamic republic.

The altered picture of Mirzakhani, who this week became the first woman awarded the Fields Medal, mathematics' equivalent of the Nobel Prize, was published in the Iranian reformist daily "Sharq," whose journalist tweeted the snarky quip about the manipulation of the image.

Mirzakhani's achievement appears to have created a challenge for Iranian newspapers forced to follow stringent written and unwritten censorship guidelines concerning images exposed female skin and hair.

Women in Iran are required to wear the Islamic hijab to cover their hair and body, and newspapers and websites often digitally alter pictures of women to make them acceptable to censors and hard-liners.

U.S. first lady Michelle Obama and EU foreign-policy chief Catherine Ashton are among women whose photographs have been doctored by the Iranian media in recent years.

Other images of Mirzakhani, a professor at Stanford, also appear to have undergone digital editing in order to be published by Iranian newspapers.

While some conservative media -- including the hard-line "Kayhan" daily -- completely ignored Mirzakhani's achievement, others posted an old picture of her wearing the hijab.

The government-run daily "Iran" appears to have photoshopped a scarf from an old photo of Mirzakhani onto a newer image of her without the hijab. The reason for the move was not clear. "It might be because they wanted to use a high-quality photograph, but weren't allowed to publish it without adding a veil," a web project hosted by the news channel France 24 noted.

The portrait of Mirzakhani published by "Sharq" reportedly underwent several rounds of alterations before it was approved by the newspaper's editors.

Iranian journalist Farvartish Rezvaniyeh posted images on Facebook showing the changes made to the portrait by artist Hossein Safi. The original portrait stands side-by-side with a version altered by the artist, which in turn stands next to the final version published by "Sharq."

Farvartish wrote that "Sharq" had asked the artist to change his original portrait to make Mirzakhani's hair less visible, adding that the final editing was done without the artist's knowledge.

"Oops! Did we censor her picture? Seems we had to!" a journalist for the newspaper, Sobhan Hassanvand, wrote on Twitter.

Meanwhile, Iran's "Hafte Sobh" newspaper cropped Mirzakhani's photo on its front page, leaving only her face and editing out her short hair.

In a statement posted on his official website, Iranian President Hassan Rohani congratulated Mirzakhani for winning the Fields medal.

"Today the Iranians can feel proud that the first woman who has ever won the Fields Medal is their fellow citizen. Yes! The most competent must sit at the highest position and must be the most respected," Rohani said in the statement.

Rohani's unverified Twitter account -- said to be run by people close to him -- posted a Tweet featuring two photographs of Mirzakhani side-by-side, one with a head scarf and one without.

The tweet was met by cheers by some Iranians, who praised Rohani for posting an unveiled photograph of the mathematician.