Ms Prunskienė's son, Vaidotas Prunskus, said on Thursday that doctors have observed positive changes in his mother's condition.
"There have been changes for the better," he told BNS.
Commenting on doctors' prognosis, he said that "it's a disease a person does not recover from in a few days."
Ms Prunskienė was taken to Santariškės Clinics on Sunday evening and was later moved to Vilnius University Hospital where she underwent a neurological operation.
It was reported on Tuesday that her condition deteriorated following the operation but later doctors managed to stabilize it.
Ms Prunskienė was Lithuania's prime minister in the first post-independence government in 1990-1991 and served as minister of agriculture in 2004-2008. She is curently chair of the Lithuanian People's Party.
Ms Prunskienė's was found unconscious by her friends on Sunday. That evening she had plans to celebrate her birthday in a restaurant, but when her friends came to fetch her, no one answered the door. Finally, her relatives forced the door open and found the woman unconscious. She was instantly taken to hospital and put under observation in intensive care unit.
It is reported, that Ms Prunskienė suffered a stroke when a clot obstructed one of the main arteries in her brain.