Study on the Evaluation of Bone Microstructure Changes in Patients with CKD Based on Ultra-High-Resolution CT

Background: Renal osteodystrophy(ROD) is one of the common complications and an important cause of fractures, chronic pain and death in CKD patients. Bone biopsy is limited in clinical evaluation of the bone destruction due to its invasiveness. In this study, we used the non-invasive ultra-high-resolution CT independently developed by Academician Zhenchang Wang Team to explore the imaging features of bone microstructure in CKD patients, with the aim of providing imaging evidence for future precise clinical diagnosis and treatment. Methods: 36 CKD patients and 28 healthy controls matched by age and gender were collected. Data of the non-dominant radius and distal tibia were collected using ultra-high-resolution CT. After standardized image reconstruction and recombination, bone microstructure assessment was conducted on cross-sectional images at 7.5mm, 10mm and 15mm proximal to the radial epiphyseal line and 10mm and 20mm proximal to the tibial epiphyseal line, respectively. And the bone destruction and vascular wall calcification within the scanning range were evaluated. Independent sample t-tests or non-parametric tests were used for intergroup comparisons, and P<0.05 was statistically significant. Results: Among the 36 CKD patients, 22 were male, average age of 49±12.5 years and eGFR of 3.8ml/min/1.73m2. Compared with the healthy controls, the cortical bone area at the 20mm and 15mm level proximal to the tibial epiphyseal line was significantly larger in the CKD group (P=0.001; P=0.017); At the 7.5mm, 10mm and 15mm levels proximal to the radial epiphyseal line, the thickness of trabeculae was greater (P＜0.001; P＜0.001; P=0.001); The number, classification and porosity of cortical bone were all higher at the 20mm (P=0.003; P=0.006; P=0.024). and 10mm level proximal to the tibial epiphyseal line (P=0.012; P=0.006; P=0.015). At the 15mm level proximal to the radial epiphyseal line, the number, the classification and the porosity of cortical pores still showed a higher trend (P=0.017; P=0.027; P=0.028); The degree of calcification of the arterial walls in the wrist and ankle was more significant within the scan range (P<0.001). Conclusion: Ultra-high resolution CT can clearly display the bone microstructure changes, providing imaging evidence for future precise clinical diagnosis and treatment in CKD patients with renal osteopathy. Funding: Clinical Revenue Support, Government Support – Non-U.S.