RT Journal A1 Lyle DJ T1 A stereoscopic fixation attachment for the perimeter JF Archives of Ophthalmology JO Archives of Ophthalmology YR 1933 FD May 1 VO 9 IS 5 SP 817 OP 820 DO 10.1001/archopht.1933.00830010840007 UL http://dx.doi.org/10.1001/archopht.1933.00830010840007 AB Not infrequently the ophthalmologist desires to make an accurate study of the peripheral fields of an eye which has lost central vision. Charting of the central and paracentral fields is accurately done with stereoscopic instruments. Without binocular fixation field measurements are made with great difficulty and questionable precision when the patient cannot fix the eye under test.Several devices have been developed for use in fixing the eye with a central scotoma, but they are, to my knowledge, hard to adjust, and the results are inaccurate. The old time method of placing the end of the index finger of the right hand (if the patient is right-handed) on the point of fixation and then instructing the patient to direct the eye to that point is still in use. This simple method, which seems to me to be as accurate as any of the mechanical devices and attachments, is still open