RT Journal Article SR Electronic T1 The red cell osmometer. A useful inaccuracy in measurement of mean corpuscular volume in hyperosmolar states. JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 430 OP 433 DO 10.1136/jcp.33.5.430 VO 33 IS 5 A1 Allen, S C A1 Balfour, I C A1 Wise, C C YR 1980 UL http://jcp.bmj.com/content/33/5/430.abstract AB The Coulter S Counter gives a value for mean corpuscular volume which does not necessarily reflect red cell size in vivo. This phenomenon may be used in early diagnosis and hence prevention of the 'hyperosmolar syndrome'.