In the mean time the rod and the prism tests may well be taken in each case and let judgment decide as to treatment.
Thos. M. Stewart.
I agree with the writer that the rod test is the more scientific test for heterophoria, and of late years have virtually discarded the prism test, except in special cases. The tables are interesting, but their value would be materially increased if the author would supplement them with tables showing the refraction, and inflammation or its results.
Was it an accident that Stevens’ phorometer showed the same amount of right hyperphoria in one-ninth of the cases, and in thirteen of thirty-three cases of left hyperphoria? In which of these cases was there anisometropia and of what kind was it?
What was the refraction of the two cases of exophoria, two of left and one of right hyperphoria by the phorometer; and was the refraction the same in the six cases which were orthophoric by both rod and prism?
Such studies are necessary to a clear understanding of the relative value of these tests.
John L. Moffat.
Dear Dr. Deady: Your letter and inclosed article on “The Maddox Rod or Phorometer; Which?” has been received and examined with interest.
I have examined a good many cases in my office by both methods and find variable results, but where there is a radical difference I have found the Maddox rod the more accurate, and from experience I have learned to rely upon it instead of the phorometer, as in prescribing prisms in hyperphoria in connection with glasses for constant use I rely wholly upon the rod test.
J. M. Fawcett.