ABSTRACT
I. Introduction 559
II. Definition of SPN 560
III. Differential Diagnosis of the SPN 561
IV. Morphologic Evaluation of SPNs 562
A. Distribution of SPNs 562
B. Size 563
C. Growth Rate 563
D. Margins, Contours, and Marginal Changes 564
E. Cavitation 568
F. Fat 571
G. Calcification 571
H. MR Signal Intensity 574
V. Flow and Perfusion of SPNs 576
A. CT and MR Nodular Enhancement 576
References 576
I. Introduction
The solitary pulmonary nodule (SPN) is one of the most common radiologic
abnormalities detected in daily practice. In fact, it is estimated that up to one
in every 500 chest radiographs demonstrates a lung nodule (1,2). Since the
introduction of computed tomography (CT), especially helical CT, the number
of incidental findings of SPN has increased.
