Assessment of bone mineral density according to computed tomography in patients with urolithiasis

Introduction. The incidence of urolithiasis associated with impaired bone density is increasing in Russia. Computed tomography (CT) is used to diagnose urolithiasis but does not routinely allow direct assessment of bone mineral density. A method of asynchronous quantitative computed tomography with phantom has been proposed, which enables automated assessment.

Objective. To evaluate the bone mineral density of vertebral bodies in patients with urolithiasis using computed tomography data.

Materials and methods. The automatic evaluation was performed by the Ka-Med hardware and software package. The Ka-Med includes a phantom for asynchronous calibration of the CT scanner and software. The phantom simulates the lumbar spine with varying concentrations of potassium hydrophosphate solution: the volumetric bone mineral density ranging from «osteoporosis» to «normal». The phantom scan data was uploaded to the software. In the software calibration curve was automatically constructed for conversion from X-ray density (HU) to bone mineral density (mg/ml). Bone mineral density was assessed in 65 patients diagnosed with urolithiasis according to the American College of Radiology 2023 criteria and compared with normative data from the University of California.

Results. It was found that 7 patients had bone mineral density corresponded to osteoporosis, 27 patients had osteopenia and 31 patients were normal bone mineral density. Bone mineral density was significantly lower compared to normative data: in men (-1.05; p<0.001) and in women (-0.49; p<0.008).

Conclusion. An automatic assessment of the mineral density of vertebral bodies in patients with urolithiasis was performed using computed tomography data. A significant decrease in bone mineral density relative to normative data was observed.