W. Bocker et al., AUTOMATED SCORING OF MICRONUCLEI IN BINUCLEATED HUMAN-LYMPHOCYTES, International journal of radiation biology, 70(5), 1996, pp. 529-537
Citations number
20
Categorie Soggetti
Radiology,Nuclear Medicine & Medical Imaging","Nuclear Sciences & Tecnology
Manual and automatic scoring of micronuclei (MN) in binucleated human
lymphocytes (BNC) were compared after irradiation of whole blood sampl
es. The blood samples were irradiated with X-ray doses (1, 2 or 3 Gy)
and stained with Giemsa. The preparation technique was optimized in su
ch a way that acceptable conditions (cell density, contrast) were obta
ined for both scoring procedures. To estimate the quality of automatic
micronucleus detection, two researchers who had different experience
in scoring MN (6 months and 5 years) analysed the samples independentl
y from each other. Automatic scoring was carried out with a digital im
age analysis system and the recognition procedure was divided into two
parts. The BNC positions were detected with low microscope magnificat
ion (100x), and the recognition of micronuclei within the cytoplasm of
the classified BNC was carried out at high magnification (630x). A fu
zzy logic classification system as well as two different segmentation
steps (preclassification and postclassification) made it possible that
about 94% of all automatically recognized BNC were classified correct
ly). On the other hand, the classification system was optimized in suc
h a way that false positive decisions were minimized (95% of automatic
ally recognized micronuclei were classified correctly). Failure to rec
ognize micronuclei (8.5%-25% false negatives) was mainly due to extrem
ely small micronuclei, poor contrast with respect to the cytoplasm, an
d aggregation of micronuclei especially at higher doses.