Evaluation of a Solitary Pulmonary Nodule with Diffusion-Weighted MRI

Signal Intensity	Score
none or faint (much less than the thoracic spinal cord)	1
less than the thoracic spinal cord	2
comparable to the thoracic spinal cord	3
greater than the thoracic spinal cord	4
much greater than that of the thoracic spinal cord	5

 

Malignant nodules tend to have a higher signal intensity score.

 

Performance at a cutoff >= 3 indicating a malignant nodule:

• The sensitivity was 80% and specificity 61% (Youden 41%).

• The overall accuracy was 80%.

 

False positives may occur with:

(1) granulomas

(2) inflammatory lung nodules

(3) fibrous nodules

 

False negatives may occur with:

(1) small metastatic tumors

(2) bronchoalveolar carcinoma

(3) a nonsolid adenocarcinoma