An Indian baby girl was diagnosed with a rare disorder known as hydrocephalus, causing her head to swell up to three times its normal size.

Roona Begum, a 15 month old Indian baby girl was diagnosed with a rare disorder known as hydrocephalus, causing her head to swell up to three times its normal size. However, doctors say that despite her serious condition, the girl is "doing well."

The disorder is known to cause fluids to build up in the brain, causing the swelling. The girl's condition was discovered earlier this month but her parents are too poor to pay for treatment. 

The Fortis Foundation flew in Roona and her parent free of charge from their rural village in Tripura, India to India's largest private hospital in Gurgoan, near Delhi. Roona is now scheduled to have a surgery that will have the excess fluid drained in a procedure taking place Friday.

Her doctor, leading Indian neurosurgeon Sandeep Vaishya, who heads neurosurgery at the flagship hospital run by the private Fortis Healthcare group near New Delhi told AFP that, "the child is doing well so far." But he added: "Her case is very complex so we are currently considering options of how best to proceed."

Doctors are surprised that Roona has survived with this condition for 15 months when people diagnosed with this disorder don't survive for more than 12 months. Usually, the surgery while treating such patients includes a surgical insertion of a mechanism known as a shunt, which drains cerebrospinal fluid out of the brain and towards another part of the body where it can be absorbed easily into the bloodstream.

However, since Roona's head has swollen to such an extent in comparison to her body, it complicates matters. "Her head is several times larger than her abdomen, so we have to consider how that much fluid will be absorbed by her body if we put in a shunt," Vaishya said.

"I am also worried because she has developed a skin condition on the base of her head, suggesting that her scalp is quite delicate, so a shunt could pierce through and leak fluid through the skin, causing other problems," he said.

Donations for Roona's surgery can be made on this website, which has already gathered $34,000.

According to the U.S. government's National Institute of Neurological Disorders and Stroke, about one in every 500 children suffers from hydrocephalus.