Art detectives took a look at the "Mona Lisa" using magnification techniques not available to Leonardo da Vinci himself and say they have found,  hidden in her pupils, tiny letters and numbers.

And they were placed there by da Vinci, they say.

Said Silvano Vinceti, president of Italy’s National Committee for Cultural Heritage
‘In the right eye appear to be the letters LV which could well stand for his name, Leonardo da Vinci, while in the left eye there are also symbols but they are not as defined.   It is very difficult to make them out clearly but they appear to be the letters CE, or it could be the letter B.    In the arch of the bridge in the background the number 72 can be seen or it could be an L and the number 2.

‘You have to remember the picture is almost 500 years old so it is not as sharp and clear as when first painted.
The "Mona Lisa" has fascinated people for centuries.  Given da Vinci's love of riddles, and a good joke, there is even speculation he is the Mona Lisa.   So one group wants to exhume his body and try to do a computer reconstruction of his face.

letters and numbers in mona lisa eyes

That may be going a bit far but it's good that da Vinci keeps us guessing hundreds of years after his death.  And who knows what Dan Brown will make of it in his next novel.