Automatic matching of the pulmonary nodules in current and former CT studies: a clinical evaluation

It is important to determine that the nodules detected by radiologists on a CT scan are benign or malignant. One method of distinguishing a benign nodule from a malignant one is to evaluate the growth of the nodule over a period of time. After the follow-up scan, the radiologist has to manually identify and locate the same nodule in the two scans and evaluate the growth. With the introduction of multi-slice CT (MSCT) the number of slices in chest CT exams has increased significantly, making it very difficult and time consuming for the radiologists to scroll through the entire set of images. An automatic tool, which registers the two studies and help the radiologist scroll through the two studies simultaneously and locate the nodule or find the nodule in other study by clicking on it in the other study, would be very beneficial to them. This paper evaluates one such automatic tool on the cases under several different clinical conditions. (C) 2004 CARS and Elsevier B.V. All rights reserved.