A WOMAN who died of a rare form of dementia spent the last two and a half years of her life in a coma, an inquest heard.

An inquest heard that retired newsagent Catherine Brown, 68, suffered from the brain disorder Binswanger's disease for which there is no cure.

And her son, dentist David Brown told the inquest how at times during his mother's long illness it seemed as if she was aware of what was going on and at others she was in a deep sleep.

"Her quality of life was so poor and we felt helpless to do anything about it," said Mr Brown.

"We didn't know what the cause of her illness was and at least the inquest has helped us to understand that."

Mrs Brown spent the last two and a half years of her life in hospital and finally Nazareth House Nursing Home, Preston New Road, Blackburn.

Dr Timothy Dawson, consultant pathologist at the Royal Preston Hospital, said the main feature of Mrs Brown's complicated medical history had been the coma which had been preceded by various episodes of depression.

He said that at one stage a doctor in Leeds had considered Binswanger's as a possibility.

The disease is known to be slowly progressive with a life expectancy of five years after onset.

A sufferer is typically left with memory loss, mood changes as well as difficulty in walking.

Mrs Brown also suffered from diabetes and the cause of death was given as diabetic ulcers and sepsis caused by insulin dependent diabetes.

Dr Dawson said that one of the possible treatments was to use stimulants such as amphetamine which he said had been used on Mrs Brown without success. There is no known cure.

Dr Dawson said it was difficult to say how widespread the disease was because in many cases it was not detected even at autopsy as death was attributed to other, more obvious causes.

"It really does require a significant investigation of the brain by a specialist to detect the disease," he said.

Recording a verdict of natural causes, coroner Michael Singleton said the years leading up to Mrs Brown's death had clearly been very difficult for the family.

Mrs Brown and her husband Duncan, who lives in Quebec Road, Blackburn, ran the newsagents in Lammack Road for 18 years.

They have three children, David, Christine and Susan who lives in America.