The blue field entoptic test with normal patients.

One hundred normal patients were evaluated with the Blue Field Entoptoscope test. Of those one hundred patients, ninety-nine were able to describe the appearance of their own leukocytes. The methodology did not permit encouraging or coaching patients to see their leukocytes. Of the ninety-nine who could perceive their own leukocytes, nineteen 19.19%) were unable to perceive an approximately equal number in each of the four quadrants of the blue field of light which is divided by a reticle. These patients who did not see an equal number of leukocytes in all four quadrants were generally older than those who saw an equal number of leukocytes. The results indicate that if the Blue Field Entoptoscope is to be used in clinical practice or research, it is useful to standardize the instrument for the population studied. In particular, the instrument should be standardized for age.