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The rise and fall of caecanometry
Gregory L Stephens1, David Perrigin
1College of Optometry, University of Houston, 505 J. Davis Armistead Bldg., Houston, TX 77204-2020, USA. gstephens@uh.edu
Abstract:
Caecanometry was a short-lived visual fields examination technique first described by Ingwold Davidsen, O.D. in 1949. The technique was based upon the unusual premise that the blind spot constricted in size when certain types of infection were present above the level of the shoulder blades. The Davidsen-Wottring caecanometer was patented as a device for plotting blind spot size and shape. Caecanometry was practiced mainly in the southern U.S., dying out in the middle 1970s.
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