Blue field entoptic phenomenon in cataract patients.

The blue field entoptic phenomenon (BFE), which allows the observation of one's own leukocytes flowing in macular retinal capillaries, was used to predict postoperative macular function in 136 consecutive patients undergoing uncomplicated cataract operation. The results were compared to those obtained with three commonly used tests: two-light discrimination, color perception, and the Purkinje vascular entoptic phenomenon. All four tests identified a nearly equal number of the good maculae (visual acuity 20/40 of better) ranging from 87% for the two-light discrimination test to 94% for the BFE test. However, the tests varied greatly in predicting poor macular function (visual acuity 20/50 or worse). The BFE test identified more than 75% of the poor maculae; the Purkinje vascular entoptic test and the two-light discrimination test, only 22%; and the color perception test, 11%. A positive response to the BFE test indicated a .98 probability of good macular function; a negative response indicated a .82 probability of poor macular function, predictions that were better than the other three tests or their combination.