Poikilocytosis is a general term used to describe variations in shape. Practically, however, this term has little meaning since cells varying in shape must be specifically identified to be of diagnostic value to the clinician. The work of the French hematologist, Marcel Bessis, with the scanning electron microscope has significantly increased our understanding of the various unusual shapes erythrocytes may assume and their associated pathophysiologies.
Inconsistent terminology may hamper communication about red cell morphology, in that various terms are used to describe the same type of change. Uniform terminology based on Greek roots has been applied in an attempt to provide standardization, although it has not been widely accepted.