What causes a bright spot in the direct line of vision?

Answer 1

They vary in cause, but sometimes they are caused by dead blood cells clumping in the vitreous fluid around your eye. Sometimes though they can be caused by retinal detachment. But this is not likely, because retinal detachment is very rare.

Answer 2

On the information given, the most likely cause is a simple floater. This is a change in the vitreous humor of the eye which casts a shadow onto the retina. If this happens to be in the line of sight, it will move with the eye and always appear directly ahead. Floaters rarely indicate serious problems, and most people acquire a few over time, but a sudden fresh batch of floaters, especially if accompanied with any bright flashing lights in the vision, should be followed up medically for the UNLIKELY (2% max) chance of an early retinal detachment. Other causes of a spot in the direct line of vision are rarer but indicate a problem with the macula. This can be macular degeneration which is relatively common in the elderly, central serous maculopathy which is more common in younger people but is often self-resolving, localised macular haemorrhage and reaction to certain medications and drugs most commonly anti-malarials.