A neurologist has finally deciphered the mysterious disease that led to the death of the woman depicted in one of the world's most famous paintings in the US.
"Christina's World" by Andrew Wyeth, which hangs in the Museum of Modern Art in New York, depicts a young woman in a field, gazing at a farmhouse on an idyllic summer day.
The subject in the painting is Christina Olson, Wyeth's good friend and neighbour.
For most of her life, she suffered from a mysterious disorder which slowly took away her ability to walk, and eventually to use her hands.
She died at age 74 after a difficult life and her disease has never been diagnosed.
Now, after closely examining a range of evidence about her condition, Mayo Clinic child neurologist Marc Patterson has pinpointed a diagnosis.
According to him, she likely had an early-onset form of Charcot-Marie-Tooth Disease -- a group of inherited disorders that affect the peripheral nerves and can lead to significant problems with movement.
"This was a fascinating case. This painting has long been a favourite of mine and the question of Christina's ailment was an intriguing medical mystery. I think her case best fits the profile of this disease," said Dr Patterson.
Patterson, professor of neurology, pediatrics and medical genetics at Mayo Clinic in Minnesota, reviewed her medical history and also considered Wyeth's art that portrayed her, including "Christina's World".
"This is a amazing piece of medical detective work. It brings home the fact that medicine has learned enormous amounts in the past few decades," added Philip A Mackowiak, MD from University of Maryland's school of medicine.
He delivered the diagnosis at the 23nd annual "Historical Clinicopathological Conference" at the University of Maryland on Friday.
The conference was devoted to the diagnosis of disorders that afflicted historical figures.