Correspondence Address:
K S Mehra
College of Medical Sciences, Banaras Hindu University, Varanasi-5
India

Full Text

Sometimes patients are brought to us, complaining of sudden and total loss of vion in one or both eyes who have normal fundi and whose pupils are normal in size and shape and re­action to light.

Such cases can only be seen either if there is some lesion of sudden onset in the occipital cortex round about the calcarine fissures-trauma, vascular le­sion or some vasospasm of retinal blood vessels or rarely in unilateral cases of retrobulbar neuritis. In cases where there is vasospasm, the loss of vision is transient and in retrobulbar neuritis the pupillary reaction is un­sustained. In the absence of such organic lesions the only conditions that remain for diagnosis are hysterical amblyopia and malingering. Such pa­tients are usually young persons-more commonly females of the age group 15 to 30 years. On taking a detailed his­tory, one can usually find a cause for such feigning of loss of vision.

The various tests- low convex glass in front of the blind eye and a +20 D tens in front of the good eye and diplopia tests with prism confirm that the patient is malingering blind­ness in one eye.

We came across four such patients --two who were malingering blindness in both the eyes and two in one eye. After taking proper history and ex­cluding other organic causes which could have given rise to such sudden loss of vision, malingering could be confirmed by the diplopia test.

Treatment. The patient was asked to lie down. No local anesthesia was put in the affected eyes and 0.25 cc of normal saline was injected subconjunc­tivally in the affected eye as near the limbus as possible in the upper half.

This injection produced a lot of pain and then it was further explained to the patient that more of it would be injected if the patient had not regained vision. To our surprise, we found that all the four patients reported re­covery of vision in one or both the affected eyes just after the injection.

All these four who had complained of sudden and complete loss of vision in one or both eyes had normal central nervous system, normal fundus and normal pupls in size and reaction to light.

In each of them there was some cause for frustration, despair or dis­appointment.

In case 1 there was a bilateral loss after she was forced to do a lot of household work at the place of her in­laws.

In case 2, the patient who was asked to mind his brother's shop during his absence was surprised by the early re­turn of his brother who demanded the accounts.

In case 3, a recently married girl of 18 had found it difficult to stay with her in-laws, without her husband who had returned to Bananas for studies.

In case 4, in a quarrel between the patient and her mother-in-law, the husband had taken the side of his mother.

 Summary