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Purpose: The purpose was to investigate the effects of short acquisition time on the image quality and the lesion detectability of oncological 18F-FDG total-body PET/CT. Methods: Nineteen oncological patients (6/13 women/men, age 65.6 ± 9.4 years) underwent total-body PET/CT on uEXPLORER scanner using 3D list mode. The administration of 18F-FDG was weight-based (4.4 MBq/kg). The acquisition time was 900 s, and PET data were reconstructed into 900-, 180-, 120-, 60-, 30-, and 18-s duration groups. The subjective PET image quality was scored using a 5-point scale (5, excellent; 1, poor) in 3 perspectives: overall quality, noise, and lesion conspicuity. The objective image quality was evaluated by SUVmax and standard deviation (SD) of the liver, SUVmax of the tumor, and tumor-to-background ratio (TBR). The lesion detectability was the percentage of identifiable lesions in the groups of 180 to 18 s using the group 900 s as reference. Results: Our results showed that sufficient and acceptable subjective image quality could be achieved with 60- and 30-s groups, and good image quality scores were given to 180- and 120-s groups without significant difference. For shortened acquisition time, SD was increased, while SUVmax of tumor and TBR remained unchanged. The lesion detectability was decreased with shorter acquisition time, but the detection performance could be maintained until the 60-s group compared with the 900-s group, although the image quality degraded. Conclusion: The total-body PET/CT can significantly shorten the acquisition time with maintained lesion detectability and image quality. [ABSTRACT FROM AUTHOR]

Purpose: The purpose was to investigate the effects of short acquisition time on the image quality and the lesion detectability of oncological 18 F-FDG total-body PET/CT., Methods: Nineteen oncological patients (6/13 women/men, age 65.6 ± 9.4 years) underwent total-body PET/CT on uEXPLORER scanner using 3D list mode. The administration of 18 F-FDG was weight-based (4.4 MBq/kg). The acquisition time was 900 s, and PET data were reconstructed into 900-, 180-, 120-, 60-, 30-, and 18-s duration groups. The subjective PET image quality was scored using a 5-point scale (5, excellent; 1, poor) in 3 perspectives: overall quality, noise, and lesion conspicuity. The objective image quality was evaluated by SUV max and standard deviation (SD) of the liver, SUV max of the tumor, and tumor-to-background ratio (TBR). The lesion detectability was the percentage of identifiable lesions in the groups of 180 to 18 s using the group 900 s as reference., Results: Our results showed that sufficient and acceptable subjective image quality could be achieved with 60- and 30-s groups, and good image quality scores were given to 180- and 120-s groups without significant difference. For shortened acquisition time, SD was increased, while SUV max of tumor and TBR remained unchanged. The lesion detectability was decreased with shorter acquisition time, but the detection performance could be maintained until the 60-s group compared with the 900-s group, although the image quality degraded., Conclusion: The total-body PET/CT can significantly shorten the acquisition time with maintained lesion detectability and image quality.

Objective: To investigate the potential utility of microangiography with synchrotron radiation to detect murine hepatocellular carcinoma (HCC) angiogenesis using an ex vivo model system., Methods: An HCC xenograft model was established by implanting HCCLM3 cells into male mice livers (n = 6). Twenty-eight days later, three of the mice were randomly selected for barium sulfate infusion into the liver and tumor via the inferior vena cava followed by ligation of the arteries, veins and common bile duct; the remaining three mice were left untreated and served as controls. All mice were sacrificed to collect livers for analysis using the BL13W beamline X-ray imager (Shanghai Synchrotron Radiation Facility, China). In addition, the tumor vasculature was evaluated by immunostaining of formalin-fixed tissues for CD31, CD34, and F8., Results: High resolution images of tumor angiogenesis were acquired and image analysis indicated that the normal blood vessels had been displaced by the fast growing tumors. Abundant and tortuous tumor angiogenesis in the tumor periphery area and sparse angiogenesis inside the tumor were also visualized clearly. These features were similar to the immunohistological results. The smallest tumor vessels visualized were approximately 20 mum in diameter., Conclusion: Microangiography with synchrotron radiation using barium sulfate as contrast agent is a viable imaging strategy for tumor angiogenesis.

Objective: To study the clinical results of posterior pedicle screw fixation, transpedicular bone grafting and vertebral canaloplasty with ilium autografting in treating serious burst thoracolumbar fracture., Methods: From March 2004 to March 2008,10 patients with serious burst thoracolumbar fracture, including 7 males and 3 females with age for 24-58 years (mean 41 years)were treated by posterior pedicle screw fixation, transpedicular bone grafting and total laminectomy with preservation of spinal process and vertebral canaloplasty with ilium autografting. The operative effects were assessed according to Frankel classification and radiologic results., Results: All patients were followed up from 1 to 4 years. There was no loosening or broken in instrumentation. The anterior edge height of the fractured vertebrae body was restored from (21.00 +/- 12.00)% to (95.00 +/- 4.20)%, and the posterior edge height of the fractured vertebrae body was restored from (70.00 +/- 15.00)% to (96.00 +/- 3.20)% postoperatively, which both demonstrated improvement compared with preoperative instance (P < 0.01). The Cobb angle was restored from (32.80 +/- 8.20) degrees to (4.20 +/- 1.60) degrees which also demonstrated improvement compared with the preoperative Cobb angle (P < 0.01). At least one grade recovery was observed in all cases except one patient with preoperative Frankel A degree. The result of Denis classification, P1, had 4 cases, P2 had 4, P3 had 1, P4 had 1., Conclusion: Posterior pedicle screw fixation, transpedicular bone grafting and vertebral canaloplasty can obtain satisfactory results treating serious burst thoracolumbar fractures. It is a feasible method with advantages of simple operation, good efficacy, preservation of structure of posterior column which should be applied clinically.