title: Comparative analysis of aggregate shapes by digitized microscopic images. Application to hypertension.
abstract: The main objective of the present work was to study modifications in RBC aggregate morphology by analyzing digitized microscopic images and compare them between healthy subjects and patients suffering from essential hypertension. Blood samples were obtained from normal subjects (n=30) and patients suffering from essential hypertension (n=20). RBC aggregate morphology was quantified using direct microscopic observation and numerical analysis of images. ASP (Aggregation Shape Parameter) defined as the ratio of the area of the projected image to its square perimeter was calculated. Other rheological parameters have been determined in order to establish the hemorheological profile of the studied hypertension states. ASP appears significantly higher (p<0.001) in patients suffering essential hypertension (0.69+/-0.11) than in normal control subjects (0.25+/-0.12). RBC aggregation is known to be responsible for the high increase in apparent blood viscosity at low shear rates. By compare ASP values with whole blood viscosity at low rate (2.30 s(-1)) a high correlation was formed between both parameters (Spearman coefficient was 0.8835 and p<0.001). The applied method is simple, direct and quantitative and provides a useful tool for measuring deviations of RBC aggregate morphology.
authors.affiliation: Laboratorio de Inmuno-Hemorrelogia, Departamento de Bioquímica Clínica, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR. Suipacha 531-2000 Rosario, Argentina. pforesto@fbioyf.unr.edu.ar
authors.forename: Patricia
authors.initials: P
authors.lastname: Foresto
authors.forename: Mabel
authors.initials: M
authors.lastname: D'Arrigo
authors.forename: Liliana
authors.initials: L
authors.lastname: Racca
authors.forename: Fernando
authors.initials: F
authors.lastname: Filippini
authors.forename: Roberto
authors.initials: R
authors.lastname: Gallo
authors.forename: Juana
authors.initials: J
authors.lastname: Valverde
authors.forename: Rodolfo J
authors.initials: RJ
authors.lastname: Rasia
mesh_terms: D000328:Adult; D000368:Aged; D001809:Blood Viscosity; D016022:Case-Control Studies; D004903:Erythrocyte Aggregation; D004912:Erythrocytes / Q000166:cytology; D005260:Female; D018056:Hemorheology; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000175:diagnosis; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged