Hi,
Thank you for posting your query.
Your symptoms require evaluation. Possibilities include migraine with aura. Visual auras are common in patients with migraine. In most cases, these visual symptoms are followed by 
headaches, however, in some cases, headaches may not occur even after the aura.
Other rare possibility could be 
transient brain ischemia (lack of blood flow to brain), especially if you have risk factors such as 
diabetes, high BP or 
cholesterol.
Please 
consult a neurologist for evaluation.
I hope it helps. Please get back if you require any additional information.
Wishing you good health,
Dr Sudhir Kumar MD (Internal Medicine), DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad, India
Click on this link to ask me a DIRECT QUERY: http://bit.ly/Dr-Sudhir-kumar
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