Migraine could cause sudden bout of blindness

Hyderabad: India has a large number of people suffering from severe migraine, and one in 200 of them suffer from a lesser known condition called retinal migraine. If you have a migraine that lasts for more than 48 to 72 hours, or have constant pain in the back of the head, you may experience loss of vision in one eye for 15 to 20 minutes, due to retinal migraine.

In retinal migraine the blood circulation to the eye is affected. It is seen mostly in the age-group of 20 to 40 years. Vision problems that affect one eye, such as flashing lights, blind spots in the field of vision or blindness for a few minutes or up to 30 minutes, occur in ocular migraines.

Dr Sudhir Kumar, senior consultant neurologist, said, “retinal migraine can be a part of migraine, which has no specific cause. It can occur with other disease conditions which affect blood vessels in multiple body parts (including retina), such as systemic lupus erythematosus, vasculitis and deficiency of clotting factors (Protein C and S). Exercise, change of posture and use of oral contraceptive pills may precipitate an attack of retinal migraine.”

While regular migraines are also found to cause vision problems and field spots, retinal migraine is observed when the patient continues to have problems in one eye. It can be diagnosed on the basis of history of headaches and the duration from when the vision problems have been recurring in episodic attacks.

Dr G.S.S. Pavan, consultant neurologist, says diagnosing the problem is missed out due to lack of awareness among general physicians. “If a person has repeated attacks of vision loss affecting only one eye, which recovers in less than 60 minutes on its own, with or without headache, a diagnosis of retinal migraine can be considered.”

The sudden loss of vision can affect a person badly if he is driving or operating heavy machinery. In some patients, the disease is very severe and as if not detected early, can lead to complete loss of vision.

Its cause is unknown
What causes the blood supply to be blocked in eyes is not yet known in the case of retinal migraine. Dr Sreelakshmi Nimmagadda, cataract and lasik surgeon, says that retinal migraines require proper treatment and in most cases, vision has been restored. But there have been a few severe cases where restoration of the vision was not possible.