M.Sc Thesis

M.Sc StudentWiner Matan
SubjectNoninvasive in Vivo Microscopy of Human Leucocytes
DepartmentDepartment of Biomedical Engineering
Supervisor ASSOCIATE PROF. Dvir Yelin
Full Thesis textFull thesis text - English Version


Detailed analysis of the leucocytes (white blood cells) in patients is an important part of most blood tests, providing a strong indication regarding the status of the patient’s immune system. Differential leucocytes count, i.e. counting all the different types of leucocytes, is required for the diagnosis of a variety of illnesses, including allergies, various malignancies, and immunodeficiency diseases such as the acquired immunodeficiency syndrome (AIDS). The two most common types of leucocyte in healthy adults are the neutrophils and the lymphocytes, which typically comprise approximately 60% and 30% of the total leucocyte population, respectively. Differentiation between these two main cell types is often required for identifying sources of infection in ill patients; higher-than-normal neutrophil count may indicate active immune response to bacterial or fungal infection, while high lymphocyte count may indicate a viral infection. By assisting the diagnosis of the source of infection, particularly at the point of care, an accurate differential neutrophil-lymphocyte count could help reduce the prescription of unnecessary antibiotics, which is known as one of the main challenges of modern medicine. In this work, we employ a recently developed system for noninvasive imaging of blood cells, termed spectrally encoded flow cytometry (SEFC), for high-resolution microscopy of leucocytes within small blood vessels in human volunteers. Based on early in vitro imaging control experiments we define specific criteria for visually identifying the two major leucocyte types and study their in-vivo characteristic appearance in different vessels diameters and at different imaging depths within the vessel. In this work we show that mean grey level is a clear suppuration parameter between the two leucocytes morphological groups we further indicate in this study the optimal location for data acquisition.  The results demonstrate the potential of SEFC to noninvasively conduct differential leucocyte count in human patients at the point of care.