Feasibility analysis of low-dose CT with asynchronous quantitative computed tomography to assess vBMD

Area of Science:

• Radiology
• Medical Imaging
• Bone Densitometry

Background:

• Assessing volumetric bone mineral density (vBMD) is crucial for diagnosing osteoporosis and monitoring treatment.
• Traditional methods for vBMD assessment may involve additional radiation exposure or separate examination appointments.
• Low-dose computed tomography (LDCT) is increasingly used for lung cancer screening, offering potential for incidental findings.

Purpose of the Study:

• To evaluate the feasibility of using LDCT in conjunction with asynchronous quantitative computed tomography (QCT) for vBMD assessment.
• To determine if LDCT-based QCT can accurately measure vBMD without increasing radiation dose or patient burden.

Main Methods:

• A study included 416 women undergoing chest CT examinations, with participants self-selecting either LDCT or conventional-dose CT (CDCT) protocols.
• Radiation doses were recorded (CTDIvol, DLP), and effective dose (ED) was calculated, categorizing scans into LDCT (ED ≤ 1.0 mSv) and CDCT groups.
• vBMD of the T12-L2 vertebrae was measured using asynchronous QCT on both LDCT and CDCT images without additional radiation exposure.

Main Results:

• No significant differences in vBMD were observed between age groups within either the LDCT or CDCT groups.
• vBMD measurements were not correlated with radiation dose parameters (mAs, CTDIvol, DLP) in either group.
• Crucially, there was no statistically significant difference in vBMD between the LDCT and CDCT groups, despite differences in radiation dose parameters.

Conclusions:

• LDCT combined with asynchronous QCT provides a reliable method for assessing vBMD.
• This integrated approach enables simultaneous evaluation of vBMD alongside screening for thoracic diseases like lung cancer.
• The method offers significant advantages, including no extra radiation, no additional patient time, and no increased economic cost.