COMPARISON OF PULMONARY NODULE DETECTION, READING TIMES AND PATIENT DOSES OF ULTRA-LOW DOSE CT, STANDARD DOSE CT AND...

Area of Science:

• Radiology and Imaging
• Medical Physics
• Diagnostic Accuracy

Background:

• Pulmonary nodule detection is crucial for early lung cancer diagnosis.
• Optimizing imaging techniques balances diagnostic performance with patient radiation dose.
• Ultra-low dose computed tomography (ULD-CT) aims to reduce radiation exposure compared to standard dose CT (SD-CT).

Purpose of the Study:

• To compare the performance of ULD-CT, SD-CT, and digital radiography (DR) in pulmonary nodule detection.
• To evaluate reading times and patient radiation doses across the three imaging modalities.
• To determine if ULD-CT can serve as a viable alternative to SD-CT and DR.

Main Methods:

• Simulated pulmonary nodules (3-12 mm) in an anthropomorphic lung phantom across 30 cases (18 with lesions, 12 without).
• Acquisition of imaging data using ULD-CT, SD-CT, and DR.
• Interpretation by three radiologists in a free-response study, with performance assessed using the JAFROC figure-of-merit (FOM).

Main Results:

• No significant performance difference between ULD-CT (FOM: 0.787) and SD-CT (FOM: 0.814).
• Both CT techniques demonstrated superior performance compared to DR (FOM: 0.541).
• CT modalities generally required longer interpretation times than DR.

Conclusions:

• ULD-CT is a promising alternative to SD-CT, offering comparable diagnostic performance with significantly reduced radiation dose.
• ULD-CT and SD-CT are diagnostically superior to DR for pulmonary nodule detection.
• ULD-CT presents a valuable option for lung nodule screening, balancing efficacy and radiation safety.