A man accused of killing a consultant pathologist in a road accident should never have driven because he suffered from severe tunnel vision, a court heard.

Retired accountant Ronald Addy, 82, of Murray Walk, Darlington, denies driving dangerously, causing the death of cyclist Dr Ceri Williams, who worked at the town's Memorial Hospital.

Prosecuting, Jamie Hill, told Teesside Crown Court that Mr Addy suffered from a condition which severely restricted his field of vision and he was said to have agreed with an eye specialist that he was no longer fit to drive.

He added: "The prosecution say that the defendant was driving knowing he had tunnel vision when quite frankly he should never have been anywhere near a car."

Dr Williams, 47, who left a wife Gaynor, a midwife, and two sons and a daughter, suffered fatal head injuries after he was struck by Mr Addy's VW Polo car on the B6279 road between Staindrop and Darlington on April 3 last year.

The collision happened on a straight stretch of the road just past the Walworth crossroads on a dry, sunny evening with little traffic.

Dr Williams, who was kitted out in full cycling gear and helmet, was riding towards Darlington with Mr Addy travelling in the same direction.

Mr Hill said a witness, Kathleen Metcalfe, who was driving her car on the opposite side of the road, saw the defendant approach Dr Williams from behind and anticipated that he would slow down in order to pass the cyclist.

"To her amazement and disbelief Mr Addy did not slow down or deviate, he kept going and collided with him," he said.

Despite the "heavy impact", Mr Addy then drove on and continued his journey home.

He later contacted police, having seen an appeal for witnesses, and told officers he was not aware he had been in an accident and thought he had struck a kerb or a piece of wood.

He denied ever having had a conversation with his eye surgeon over whether his vision was good enough to drive.

White haired Mr Addy, who wore a suit and tie, was excused from sitting in the dock during the first day of the trial yesterday and was said not to be in good health.

Earlier Judge Michael Taylor told the jury that this was a "terribly tragic case" which he anticipated would last all week.