One Novel Phantom-Less Quantitative Computed Tomography System for Auto-Diagnosis of Osteoporosis Utilizes Low-Dose Chest Computed Tomography Obtained for COVID-19 Screening.

Background: The diagnosis of osteoporosis is still one of the most critical topics for orthopedic surgeons worldwide. One research direction is to use existing clinical imaging data for accurate measurements of bone mineral density (BMD) without additional radiation. Methods: A novel phantom-less quantitative computed tomography (PL-QCT) system was developed to measure BMD and diagnose osteoporosis, as our previous study reported. Compared with traditional phantom-less QCT, this tool can conduct an automatic selection of body tissues and complete the BMD calibration with high efficacy and precision. The function has great advantages in big data screening and thus expands the scope of use of this novel PL-QCT. In this study, we utilized lung cancer or COVID-19 screening low-dose computed tomography (LDCT) of 649 patients for BMD calibration by the novel PL-QCT, and we made the BMD changes with age based on this PL-QCT. Results: The results show that the novel PL-QCT can predict osteoporosis with relatively high accuracy and precision using LDCT, and the AUC values range from 0.68 to 0.88 with DXA results as diagnosis reference. The relationship between PL-QCT BMD with age is close to the real trend population (from ∼160 mg/cc in less than 30 years old to ∼70 mg/cc in greater than 80 years old for both female and male groups). Additionally, the calculation results of Pearson's r-values for correlation between CT values with BMD in different CT devices were 0.85-0.99. Conclusion: To our knowledge, it is the first time for automatic PL-QCT to evaluate the performance against dual-energy X-ray absorptiometry (DXA) in LDCT images. The results indicate that it may be a promising tool for individuals screened for low-dose chest computed tomography.

A two-step reaction to prepare a fast-hardening strontium-calcium phosphate scaffold in room temperature / 中华创伤骨科杂志

Objective To evaluate a fast-hardening strontium-calcium phosphate scaffold using a two-step reaction in room temperature.Methods The original powder phase consisted of tetracalcium phosphate (TTCP),dicalcium phosphate anhydrous (DCPA) and strontium hydrogen phosphate (DSPA).The liquid phase consisted of 20wt％ citric acid and 12wt％ polyvinylpyrrolidone K-30.Groups were designed as Sr-0,Sr-5,Sr-10,and Sr-20,according to the molar ratios of Sr/(Sr + Ca) being 0,5％,10％,and 20％ in the powder phase,respectively.The ratio 0.5 mL/g in the liquid to solid phase was used for mixing.After the scaffold was prepared,its setting time,compression strength,phase composition and structural morphology,ions release and pH value of the substrates were analyzed.Results Addition of citric acid accelerated the setting reaction.Acceptable setting time was achieved by optimizing composition of the original powder and liquid phases.On the other hand,the compression strength,phase composition and structural morphology were not affected by addition of strontium.In addition,calcium and strontium ions were detected in the substrates,without any significant change in the pH value.Conclusion This two-step reaction can be used to prepare a fast hardening strontium-calcium phosphate scaffold in room temperature.

Single incision laparoscopic right hemicolectomy: different approaches / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Single incision laparoscopic colectomy has been performed in recent years, and has been shown to be feasible and safe. This study was to assess the feasibility of single incision laparoscopic right hemicolectomy and to compare the differences in different approaches.</p><p><b>METHODS</b>This retrospective study included eighteen patients with carcinoma of caecum and ascending colon, undergoing single incision laparoscopic right hemicolectomy. This study also compared single incision laparoscopic right hemicolectomy using different approaches: (1) single incision multiport, (2) single access port and (3) glove port.</p><p><b>RESULTS</b>There was no statistical difference in surgical outcomes. Concerning the surgeon's satisfaction toward three methods, overcrowding and durability were similar but the single incision multiport was associated with the highest gas-leak and the "glove" port was associated with poor durability. However, the method of single incision multiport has the lowest average cost of the special trocar or port in each operation. The operative time and blood loss of the operations in this study were comparable to previous publications.</p><p><b>CONCLUSION</b>There was no significant difference between different approaches of single incision laparoscopic right hemicolectomy for colonic cancer in right side colon.</p>