Flashes & Floaters

Floating spots and the sensation of flashing lights are a common complaint.  Frequently patients complain that the floater is like a bug that they feel they have to swat at.

Floaters and flashes usually occur because the jelly (vitreous) of the eye is degenerating from a solid to more liquid state as the patient ages.  As we get older, the vitreous shrinks and separates

from the retina. As this separation occurs, floaters  may appear. In about half of all people, the vitreous  has separated from the retina by age 50, although many people are not aware that this process has occurred in their eye(s). At first, floaters can be

annoying, but your brain slowly learns to ignore them. After several months you may hardly notice them.

At the points where the jelly is attached to retina, tugging may occur, causing the sensation of flashes with head movement,especially in dark environments.  Floaters are occasionally due to blood if the jelly is adherent to a retinal vessel, or in diabetics.

Flashes and floaters are more common in near sighted patients, following eye trauma, following eye surgery, and in patients with inflammation of the eyes.

Most patients with flashes and floaters will NOT lose vision or develop a retinal detachment.  If you sense new floaters or flashing lights, cover each eye separately and ensure your vision has not been compromised. 

If the flashes or floaters are worsening, or accompanied by loss of vision, or loss of peripheral vision this may represent an urgent problem (retinal tear or retinal detachment).  Go to the emergency room or see your ophthalmologist as soon as possible for an eye exam.  You will require eye drops to dilate the pupils, so do not drive yourself.   The retina surgeons in Toronto are primarily located at Sunnybrook Hospital, St. Mikes Hospital and Toronto Western Hospital.  (Dr. Edsel Ing is NOT a retina surgeon.  Dr. Ken Eng at Sunnybrook is a retina surgeon, and patients often confuse the two of us.)

If the retina is torn, laser or freezing therapy (cryotherapy) may be performed.  If the retina is detached, with fluid underneath the retina, a gas bubble or surgery is usually required.


Migraine can cause flashing lights, usually in a zigzag pattern.

If you experience CONTINOUS constant flashing lights that persist despite closing your eyes, and not moving your head, let Dr. Ing know.