The nasal visual field.

The actual influence of the nose on the nasal visual field was examined by perimetric studies. Regardless of size of target stimulus or position of the face, the nasal 180° meridian could not be expanded beyond 64°. No significant differences were found in the extent of nasal field amongst Caucasians, Orientals, and Negroes. Scotopic isopters similarly did not deviate from the average photopic. The literature of theoretic and actual absolute limits of the visual field is discussed. Osterberg's calculations of rods and cones and the work of Van Buran on the ganglion cell layers substantiate a concept of a direct relationship of retinal sensory unit topography and visual field function.