ABSTRACT

According to the World Health Organization,1 it is predicted that deaths from cancer will increase from 7.4 million globally in 2004 to 11.8 million in 2030. In particular, tracheal, bronchial, and lung cancers will emerge as the sixth leading cause of death by 2030, rising from its position as the eighth leading cause in 2004. Detection of suspicious lesions in the early stages of cancer is essential to bring down the mortality rate caused by lung cancer. Computer-aided diagnosis (CAD) can play a signiŽcant role in the early detection of suspicious lesions. Several CAD schemes for lung nodules in radiographs and computed tomography (CT) have been developed.2,3 In this chapter, we introduce two CAD schemes for the detection of lung nodules. The Žrst scheme is a template matching (TM) technique using a genetic algorithm (GATM),4-8 which is presented in Section 12.2. The second

CONTENTS

12.1 Introduction ........................................................................................................................ 267 12.2 TM Using a Genetic Algorithm ....................................................................................... 268

12.2.1 TM ............................................................................................................................ 268 12.2.2 Genetic Algorithms .............................................................................................. 269 12.2.3 GATM ...................................................................................................................... 272

12.2.3.1 Structure of GATM ................................................................................. 272 12.2.3.2 Setup of Simulation Studies Investigating GATM ............................. 273 12.2.3.3 Results of the First Simulation Study Using GATM .......................... 274 12.2.3.4 Results of the Second Simulation Study Using GATM ..................... 281 12.2.3.5 Results of the Third Simulation Study Using GATM ........................ 282

12.2.4 Nodule Detection by GATM in Chest Radiographs .........................................283 12.2.5 Nodule Detection by GATM in Thoracic CT Images........................................285