Semiautomated chromosome analysis: A clinical test

Abstract

An interactive system for semiautomated [human] chromosome analysis, consisting of a high-speed image processor with light-pen, TV monitor and keyboard interfaced to a microscope with motorized scanning stage and video-camera and to a hard-copy printer, was clinically tested for 20 consecutive working days. Metaphase search takes place overnight. Identified metaphases are ranked automatically according to their suitability for analysis. Less than every 2nd metaphase found cannot be either counted or analyzed. There were 164 samples analyzed. Only 1 was not completed. Two numerical and 2 structural abnormalities were identified and clinical consequences taken. Average time per completed analysis (10 counts, 4 karyotypes) was 37.5 min (28-84). Average time varied between technicians. In another test including 120 metaphases and 40 karyotypes average time for counting the chromosomes of a metaphase was 37 s (28-48), and average time for producing one karyotype, including a hard-copy was 4 min 30 s (3 min 43 s-5 min 54 s). Number of maunual interactions was 8 (2-17) and 36 (25-61), respectively. Although improvements are possible, the system is able to at least double the output of 4 cytogenetic technicians.