Beijing, July 17 (IANS): A three-year-old Chinese girl who developed a 20-kg head due to congenital Hydrocephalus was now recovering after the excess fluid was drained out and a 3D-printed titanium alloy skull implanted, doctors said.

Hydrocephalus is a condition when abnormal amount of fluid is accumulated in the brain which causes enlargement of the head, Xinhua news agency reported.

The girl, Han Han, underwent the surgery for over 17 hours on Wednesday and remained under observation, said neurosurgeon Kuang Weiping, in charge of her treatment.

Born with hydrocephalus, Han Han was admitted to the hospital two months ago. Since September 2014, she had become bedridden as her head grew four times the normal size, taking up more than half of her total weight.

Due to the heavy weight, parts of her brain suffered serious infections and she lost her sight because her optic nerve was affected.

Kuang said they believed her skull was likely to rupture as the infected parts became thinner and only the "brain-shrinking" operation could save her life.

During the process, the neurosurgeon peeled her scalp and skull, and then drained the fluid in her head.

After the swollen structures in her brain returned to the normal size, doctors implanted the 3D-printed titanium alloy skull and covered it with her scalp.

"We were very, very careful, because brain tissue without a skull is like a peeled egg. Fortunately, it went smoothly," Kuang said.