Determining Mean Corpuscular Hemoglobin from a Drop of Blood using Contact Optical Microscopy

Abstract

Contact optical microscopy (COM) is a novel and highly compact imaging technology that has the potential to deliver a point-of-care complete blood count, which could strongly impact many fields of medicine. It was hypothesized that by using COM, Mean Corpuscular Hemoglobin (MCH) can be measured as a component of a CBC, with clinically acceptable accuracy and precision, from a drop of blood. A physical COM system, a microspectrophotometry equation, and a computer-vision algorithm were developed to extract the MCH from COM images of films of blood containing intact red blood cells. The MCH of 15 human blood samples from different subjects was measured using both a standard-of-practice Sysmex XN-10 machine and the COM system. A coefficient of variation of 4% was obtained, surpassing the clinical target of 5%. The results showed that MCH can be measured precisely using COM-based microspectrophotometry and suggest that there is potential for further precision gains.