Blood testing at the single cell level using quantitative phase and amplitude microscopy

Abstract

It has recently been shown that quantitative phase imaging methods can provide clinically relevant parameters for red blood cell analysis with unprecedented detail and sensitivity. Since the quantitative phase information is dependent on both the thickness and refractive index, a major limitation to clinical translation has been a simple and practical approach to measure both simultaneously. Here we demonstrate both theoretically and experimentally that, by combining quantitative phase with a single absorption measurement, it is possible to measure both quantities at the single cell level. We validate this approach by comparing our results to those acquired using a clinical blood analyzer. This approach to decouple the thickness and refractive index for red blood cells may be used with any quantitative phase imaging method that can operate in tandem with bright field microscopy at the Soret-band wavelength.

Real time blood testing using quantitative phase imaging

“…For this study, we use the MCHC values provided by the impedance analyzer. This hemoglobin concentration can be also measured by other methods [15,16,17,18].…”

“…The MCD, introduced by Canham and Burton, is a theoretical parameter that predicts the smallest capillary diameter that a given RBC can squeeze through and, thus, is clinically significant. Furthermore, for each cell, we are able to calculate simultaneously many other independent parameters [15], including: perimeter, circular diameter, eccentricity, minimum, maximum, and mean thickness, circularity, integrated density of the cell, and kurtosis, skewness, and variance for cell height distribution. Given the vast amount of information available about each cell, this may open up opportunities to study and characterize abnormal cells and Figure 2.…”

Quantitative phase imaging of living cells: application of the phase volume and area functions to the analysis of “nucleolar stress”

“…The fact that phase image parameters reflect cellular responses to external cues has been demonstrated earlier. [1][2][3]6,[9][10][11][12][13][14]19 Importantly, the S and W functions emerged as an important tool for monitoring local dynamics of nucleolar components. Such a dissection of phase portrait by high-resolution CPM is significant because the changes induced by Act D are neither monotonous nor are they uniformly distributed across the nucleus; general trend is a decrease of phase thickness and refractivity (Ref.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12] The phase imaging provides unique opportunity to dissect the biological object using normalized values of optical path difference (OPD). Measurement of this parameter, as well as refractivity, with exceptionally high accuracy allowed for registering the phase thickness (h) and volume-averaged refractive index of erythrocytes, [3][4][5][6][7][8] local fluctuations of cell dynamics, 1,2 and functional responses to extracellular stimuli. [3][4][5]7,[9][10][11][12][13][14] Still, the literature data on physical parameters of individual cellular compartments remain scarce (see Ref.…”

Quantitative phase imaging of arthropods

“…QPI techniques [4][5][6][7][8][9][10][11][12][13][14] are sensitive to path length changes at the nanoscale level. Previously, the QPI technique spatial light interference microscopy (SLIM) has been used for a variety of applications, such as measurement of cell growth, 15,16 testing blood, 17 characterization of intracellular movement 18 and diagnosis as well as prognosis of disease in tissue. 19,20 However, QPI has not yet been applied to whole organism imaging.…”