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OBJECTIVE In this article, a statistical-based iterative ring removal (IRR) algorithm that effectively removes ring artifacts generated by defective detector cells is proposed. METHODS The physical state of computed tomography (CT) detector elements can change dynamically owing to their temperature dependence and the varying irradiation caused by focal spot movements. This variation in the properties of cells may cause false pixel values in sinograms, resulting in rings or segments of rings in reconstructed images. In this article, the proposed algorithm is studied on clinical CT. Two patients were scanned using a clinical CT scanner (AnyScan SPECT/CT, Mediso). Artificial rings and band rings were generated on the real sinogram data to examine the algorithm in different cases. The method was performed also on real ring artifacts. RESULTS The IRR can correct both single and band-like ring artifacts with one or more defective pixels. The proposed algorithm can detect the period when pixels contain false signals and only those periods are corrected. The IRR reduces ring artifacts, even in cases where low-contrast rings occur in the reconstructed image. CONCLUSIONS This statistical correction method efficiently detects and corrects false pixel values in the projection data without causing new artifacts in the reconstructed image. The algorithm is less sensitive to its parameters.

In trauma patients, pulmonary embolism occurs in up to 4% of cases and carries a mortality of 20-50%. The incidence of deep vein thrombosis (DVT) varies from 5 to 63% depending on patients' risk factors, modality of prophylaxis, and methods of detection. For these reasons, trauma patients require adequate DVT prophylaxis.Spinal fracture or cord injury patients are at particular risk. Increasing injury severity, head injury, older age, lower limb injuries, and obesity are other risk factors. The current standard of care for DVT prophylaxis is enoxaparin (a low molecular weight heparin) as long as anticoagulation is not contraindicated. Unfractionated heparin alone does not provide sufficient protection against DVT. Selective factor Xa inhibitors such as fondaparinux are showing promising results. Other strategies for pulmonary embolism prevention include: graduated compression stockings, sequential compression devices, continuous passive motion, and prophylactic inferior vena cava filter. There is lack of consensus regarding the optimal DVT prophylaxis in trauma patients and few level I recommendations exist.Best practice in thromboprophylaxis for trauma patients will remain on the basis of recommendations until definitive risk-benefit ratios are determined to justify the use of various mechanical and pharmacological measures, in combination or alone.

Background This study reviews the efficacy of vacuum-assisted wound closure (VAWC) to obtain primary fascial closure of open abdomens after severe trauma. Methods The study population included shock resuscitation patients who had open abdomens treated with VAWC. The VAWC dressing was changed at 2- to 3-day intervals and downsized as fascial closure was completed with interrupted suture. The Trauma Research Database and the medical records were reviewed for pertinent data. Results Over 26 months, 35 patients with open abdomens were managed by VAWC. Six died early, leaving 29 patients who were discharged. Of these, 25 (86%) were successfully closed using VAWC at a mean of 7 +/- 1 days (range, 3-18 days). Of the four patients that failed VAWC, two developed fistulas. No patients developed evisceration, intra-abdominal abscess, or wound infection. Conclusion VAWC achieved early fascial closure in a high percentage of open abdomens, with an acceptable rate of complications.