Brief Answer:
Vitreous degeneration needs to be ruled out.

Detailed Answer:
Hello Sir
Welcome to health care magic.

I am Dr. Dadapeer K, an ophthalmologist and I answer health problems related to eye.

I reviewed your history.
It seems from the history that you are having symptoms of seeing a flash of light in left on eye movement.
The commonest cause for this symptom in your age is age related degeneration of the vitreous and its detachment called as posterior vitreous detachment.
Posterior vitreous detachment by itself will not cause any harm but it requires evaluation to look for few complications which can occur with it like retinal tear or detachment.
This is required in cases with sudden onset of flashes of light.
Hence I advice you to consult your ophthalmologist for examination of the posterior segment of the eye by indirect ophthalmoscopy.
If any of the problems are present they needs to be treated by laser to prevent further complications.

Hope the information is helpful to you.

Thank you
With regards

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