“Guernica” depicts intense suffering, but its own health is not in danger.

That’s the diagnosis after the first X-ray of Pablo Picasso’s 20th-century anti-war opus carried out by the Reina Sofia art museum in Madrid.

The X-ray of the large-format canvas — 11 feet by 25 feet — was part of a series of tests begun more than a year ago on one of the world’s most prized masterpieces.

The piece’s last major analysis a decade ago turned up 129 imperfections — ranging from cracks to creases to marks and stains — all attributed to the painting’s hectic past.

“The good news is that the latest X-ray results show the imperfections haven’t increased,” Reina Sofia director Manuel Borja-Villel said. “But age pardons no one, and paintings are no different.”

The studies now being pieced together by the museum’s specialists aim to produce a definitive analysis of the painting by 2010. So far, tests show the painting needs only a periodic dusting and a possible cleanup of some stains resulting from its only previous restoration, done by the Museum of Modern Art in 1957.

“Guernica” was commissioned from Picasso by the Republican government of Spain to represent the country at the Universal Exposition in Paris in 1937, as Spain writhed in a bloody civil war started by future dictator General Francisco Franco.

Once the fair was over, the painting went on the road for nearly 20 years, visiting dozens of cities on both sides of the Atlantic.

“Every time it was moved, it had to be taken off its support and rolled up. That took its toll over the years until one day at the beginning of the 1960s, Picasso himself said, ‘Enough is enough,'” Mr. Borja-Villel said.

“The painting has a robust constitution, but its traveling days are definitely over,” he added.

The painting made its final trip when it was transferred to Spain in 1981 from MoMA, where it had been deposited on a long-term loan by Picasso until democracy was restored back home.