Lung nodules: dual-kilovolt peak analysis with CT--multicenter study

Area of Science:

• Radiology
• Pulmonary Medicine
• Medical Imaging

Background:

• Differentiating benign from malignant lung nodules is crucial for patient management.
• Radiologically indeterminate lung nodules present a diagnostic challenge.
• Computed tomography (CT) is a primary imaging modality for lung nodule evaluation.

Purpose of the Study:

• To evaluate the hypothesis that a greater increase in computed tomographic (CT) number from 140-kilovolt peak (kVp) to 80-kVp images indicates a higher likelihood of a benign lung nodule.
• To determine if dual-kilovolt peak analysis can aid in characterizing indeterminate lung nodules.

Main Methods:

• Prospective study of 157 indeterminate lung nodules (5-40 mm diameter) across four institutions.
• Nodules were evaluated using non-enhanced CT scans at 140-kVp and 80-kVp with 3-mm collimation.
• The mean CT number increase between the two kilovolt peak settings was analyzed.

Main Results:

• The study included 86 benign (55%) and 71 malignant (45%) nodules.
• The median increase in mean CT number was 2 Hounsfield Units (HU) for benign nodules and 3 HU for malignant nodules.
• This difference was not statistically significant (P > 0.05), with an area under the receiver operating characteristic curve of 0.505.

Conclusions:

• Dual-kilovolt peak analysis using current CT technology is not effective for identifying benign lung nodules.
• The change in CT number between 80-kVp and 140-kVp imaging does not reliably differentiate benign from malignant indeterminate lung nodules.
• Further research may be needed to explore advanced CT techniques for nodule characterization.