A judge is set to decide whether a pensioner in a minimally conscious state should be allowed to die.
Mr Justice Hayden has been asked to resolve a dispute between the woman's daughter and specialists treating her.
Her daughter says medics should stop artificial feeding.
Doctors say life-support treatment should continue.
The judge has analysed the case at a preliminary hearing in the specialist Court of Protection, where issues relating to people who lack the mental capacity to take decisions are considered, in London.
He has ruled that the pensioner, who is in her 70s and suffered brain damage after falling and hitting her head, cannot be identified.
Bosses at Salford Royal NHS Foundation Trust, in Salford, Greater Manchester, have responsibility for the pensioner's care and have asked the judge to decide what is in her best interests.
Doctors treating the pensioner have told the judge that she is in a "minimally conscious state" and "not at the severe end of the spectrum".
One medic thought that the pensioner had recently indicated what radio station she wanted to listen to - although her daughter suspected that the medic was mistaken.
Mr Justice Hayden told lawyers that the case strayed into "extremely controversial territory".
In late 2015, Mr Justice Hayden made a ruling in a similar case which lawyers described as a landmark.
He ruled that medics could stop artificially feeding a woman in late 60s who was ''locked into the end stage'' of multiple sclerosis.
The woman died about a month after the ruling.
Medical experts had said they thought the woman - who could ''fix her vision'' and ''follow a moving object'' - was in a minimally conscious state.
Lawyers said it was the first time that a Court of Protection judge had allowed treatment to be withdrawn from someone thought to in a minimally conscious state.
The woman's daughter had asked Mr Justice Hayden to rule that life-support treatment should cease.
He had considered views plus the views of other relatives, medics involved in her treatment, carers and independent medical experts.
No one involved had opposed the daughter's application.
Four years earlier, another judge had ruled that a brain-damaged, minimally conscious 52-year-old woman should not be allowed to die.
Mr Justice Baker had said there was dignity in the life of a disabled person who was ''well cared for and kept comfortable''.
He said life-support treatment should continue and concluded that the 52-year-old woman had ''some positive experiences'' which could be ''extended''.
Mr Justice Hayden is expected to make decisions about what is in the pensioner's best interests later this year after a trial.