Episodic visual disturbance

My daughter aged 30 years had undergone open heart volvotomy in 1987. Lately she has developed an eye problem i.e. she sees black dots moving around her eyes and is losing eye sight slowly. According to opthalmologists there is nothing wrong with the retina. Neurologist have suggested MRA and VEP Test and has diagnosed her as a case of Episodic Visual Disturbance. Cardiologist has prescribed Uniwarfin tablets to make the blood thinner but is of no advantage. Please advise.


I see from your letter that your daughter underwent heart surgery when she was about 16 years old and I presume that she has been generally healthy since that time. I would expect that her doctors will have examined her carefully, to exclude the possibility that her present problem is related to her past heart condition. You obviously want to know why her vision is blurred and what is the cause of those moving spots before her eyes.

There are of course many causes of blurred vision, and one of the first things for your daughter to consider, is whether she has a simple optical problem, that is to say, does she need spectacles, or, if she already wears spectacles, do they need changing. Her ophthalmologist would have been able to advise her about this.

Your daughter complained too, of spots moving before the eyes. Sometimes such moving spots can be caused by changes in the structure of the vitreous gel of the eyes. The vitreous can change its composition, so that some parts are more fluid and some are more condensed. The condensed parts can then throw a small shadow onto the retina and the shadow is experienced visually as a 'moving spot' or a 'floater'. It appears to move, because the fluid vitreous flows when the eye changes its position of gaze, so that the shadow created by opacities in the vitreous, move too.

As your daughter was examined by an ophthalmologist, and the ophthalmologist did not mention either the need for spectacles or the presence of vitreous floaters as a cause for her symptoms, it may be necessary to look further for the cause of her symptoms. It does look as if her Neurologist is exploring other possibilities carefully and thoroughly. The tests which have been organised for your daughter should be able to tell the Neurologist much more about your daughter's visual pathway, that is the pathway leading from the retina, to the sensory visual centres of the brain. The VEP (Visually Evoked Potential) will say whether the electrical connections of the visual pathway are intact; the MRA will provide information about the vascular supply to the brain. No doubt your daughter's visual field will have been assessed and this will provide more information about her visual pathway and help to pinpoint the nature and possible causes of her problem. What is important to you, concerning your daughter's visual health, is that her doctors appear to be making the right assessments, which will help them to come to a correct decision.