Cyclic macular edema.

Three patients with macular edema noted that their vision improved during the course of the day. In one patient, a 25-year-old man, visual acuity improved from 20/40 to 20/30; in the second, a 53-year-old woman, it improved from 20/60 to 20/40; in the third, a 30-year-old man, it improved from 20/25 to 20/20. The Rayleigh match showed a wider divergence in color matches to test wavelengths during the morning hours in one patient. The Stiles-Crawford effect was abnormal in all three patients but showed no cyclic pattern. All three patients had difficulty with Arden plates, but no cyclic pattern was apparent. The cyclic change in visual acuity could not be corrected by a change in refraction and may have been the result of a change in the macular edema.