Low Tension in Acute Glaucoma.

IT is universally accepted that the cardinal sign of primary closed-angle glaucoma is a raised intra-ocular pressure. It might even be considered that it would be a contradiction in terms to make a diagnosis of acute primary closed-angle glaucoma in a soft eye. It is, however, the purpose of this article to show that, in some rare cases, such a diagnosis can be made in spite of this finding; for, apart from the low tension, most of the typical signs and symptoms of acute glaucoma are present. These include pain and blurring of vision, followed by signs of ocular congestion-ciliary and conjunctival injection, haziness of the cornea, and dilatation and oedema of the pupil. But whereas the ocular tension in a classical case of acute glaucoma may rise to about 50 to 60 mm. Hg (Schi6tz), in these exceptional cases the tension is normal (between 20 and 25 mm. Hg) or low. Confirmation of the diagnosis can be obtained by investigations and provocative tests carried out after the acute phase has passed. A typical case is described in detail below and others exhibiting the same phenomenon are briefly mentioned. A hypothesis is put forward which may account for the clinical findings, and a name is suggested for this syndrome which, to my knowledge, has not before been fully described.