Construction And Research Of A Low Cost And Automated Blood Counting System

Cell counting is one of the items in the hospital for routine blood tests.Accurate counting of blood cells in human blood is an important basis for many clinical diagnoses.Current flow-based blood counting devices require expensive and centralized medical infrastructure and are not appropriate for field use.In this paper we report a streamlined,easy-to-use method to count red blood cells(RBCs),white blood cells(WBCs),platelets,and 3-part WBC differential through a low-cost and fully-automated image-based blood counting system.The approach consists of using a compact,custom-built microscope with large field-of-view to record bright-field and fluorescence images of samples that are diluted with a single,stable reagent mixture and counted using automatic algorithms.The system consists of a camera,an objective lens,two LED light sources,two electric translation stages,a computer and other optical components.Comparing with previous work,we have improved in three aspects:firstly,the size of whole system is more compact through using self-designed components;the sample preparation requires only one reagent and the reagent is stable;the sample movement and focusing are fully automated,and a user need only press a button for the measurement and analysis to commence.Cost of the system is minimized through the use of custom-designed motorized components.We performed a series of comparative experiments by trained and untrained users on blood from 120 adults.We compare the performance of our system,as operated by high-trained,minimally-trained and untrained users,to the clinical gold standard using a Bland-Altman analysis,demonstrating good agreement of our system to the clinical standard.Statistical analysis also demonstrates ease of operability by showing no statistical difference in performance among different operator groups.The system's low cost,complete automation and good performance indicate that it can be successfully translated for use in low-resource settings where central hematology laboratories are not accessible.