Automated Detection and Volume Calculation of Nodular Lung Cancer on CT Scans

CT 영상에서 결절성 폐암의 자동추출 및 체적계산

  • Published : 2001.10.01

Abstract

This paper describes automated methods for the detection of lung nodules and their volume calculation on CT scans. Gray-level threshold methods were used to segment the thorax from the background and then the lung parenchymes from the thoracic wall and mediastinum. A scanning-ball algorithm was applied to more accurately delineate the lung boundaries, thereby incorporating peripheral nodules contiguous to pleural surface within the segmented lung parenchymes. The lesions which have the high gray value were extracted from the segmented lung parenchymes. The selected lesions include nodules, blood vessels and partial volume effects. The discriminating features such as size, solid-shape, average, standard deviation and correlation coefficient of selected lesions were used to distinguish true nodules from pseudo-lesions. Volume and circularity calculation were performed for each identified nodules. The identified nodules were sorted in descending order of the volume. These method were applied to 621 image slices of 19 cases. The sensitivity was 95% and there was no false-positive result.

본 논문은 컴퓨터단층촬영 영상에서의 자동화된 결절성 폐암의 추출 및 체적계산을 수행하였다. 배경으로부터의 흉부 분리 및 흉부로부터 폐영역으로의 분리를 위해 명암값 임계치 방법이 사용되었고, 폐 경계선 주위에 위치하는 폐암을 폐영역으로 포함시키기 위해 스캔닝-볼(Scanning-Ball) 알고리즘을 사용하였다. 폐영역으로부터 높은 명암값을 가진 부분만을 추출하는데, 이는 폐암, 혈관 또는 부분볼륨중의 하나이다. 추출된 폐암 후보자중에서 폐암을 구별하기 위해 크기, 솔리드(Solid) 형태, 평균값, 표준편차, 픽셀의 빈돗수와 명암값과의 상관계수가 사용되었으며, 식별된 폐암의 체적 및 원형율을 계산하였으며, 이를 내림차순으로 분류하였다. 19개 케이스, 총 621개 영상에 적용한 결과, 95%의 폐암추출 민감도를 가진다.

Keywords

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