66 research outputs found
Utility of cervical spinal and abdominal computed tomography in diagnosing occult pneumothorax in patients with blunt trauma: Computed tomographic imaging protocol matters
No full textEVMAN, Serdar/0000-0002-1672-966X; Guneysel, Ozlem/0000-0002-1833-2199; Akoglu, Haldun/0000-0002-1316-0308; Evman, Serdar/0000-0002-1672-966X; Altinok, Arzu Denizbasi/0000-0002-4589-8251; Akoglu, Ebru Unal/0000-0003-3674-133XWOS: 000310505100013PubMed: 22835995BACKGROUND: Small pneumothoraces (PXs), which are not initially recognized with a chest x-ray film and diagnosed by a thoracic computed tomography (CT), are described as occult PX (OCPX). The objective of this study was to evaluate cervival spine (C-spine) and abdominal CT (ACT) for diagnosing OCPX and overt PX (OVPX). METHODS: All patients with blunt trauma who presented consecutively to the emergency department during a 26-months period were included. Among all the chest CTs (CCTs) (6,155 patients) conducted during that period, 254 scans were confirmed to have a true PX. The findings in their C-spine CT and ACT were compared with the findings in CCTs. RESULTS: Among these patients, 254 had a diagnosis of PX confirmed with CCT. OCPXs were identified on the chest computed tomographic scan of 128 patients (70.3%), whereas OVPXs were evident in 54 patients (29.7%). Computed tomographic imaging of the C-spine was performed in 74% of patients with OCPX and 66.7% of patients with OVPX trauma. Only 45 (35.2%) cases of OCPX and 42 (77.8%) cases of OVPX were detected by C-spine CT. ACT was performed in almost all patients, and 121 (95.3%) of 127 of these correctly identified an existing OCPX. Sensitivity of C-spine CT and ACT was 35.1% and 96.5%, respectively; specificity was 100% and 100%, respectively. CONCLUSION: Almost all OCPXs, regardless of intrathoracic location, could be detected by ACT or by combining C-spine and abdominal computed tomographic screening for patients. If the junction of the first and second vertebra is used as the caudad extent, C-spine CT does not have sufficient power to diagnose more than a third of the cases. (J Trauma Acute Care Surg. 2012;73:874-879. Copyright (C) 2012 by Lippincott Williams & Wilkins
Determination of the appropriate catheter length and place for needle thoracostomy by using computed tomography scans of pneumothorax patients
No full textEvman, Serdar/0000-0002-1672-966X; Guneysel, Ozlem/0000-0002-1833-2199; Altinok, Arzu Denizbasi/0000-0002-4589-8251; EVMAN, Serdar/0000-0002-1672-966X; Akoglu, Haldun/0000-0002-1316-0308; Akoglu, Ebru Unal/0000-0003-3674-133XWOS: 000323940600007PubMed: 23116647Introduction: The primary goal of this study was to compare the chest wall thicknesses (CWT) at the 2nd intercostal space (ICS) at the mid-clavicular line (MCL) and 5th ICS at the mid-axillary line (MAL) in a population of patients with a CT confirmed pneumothorax (PTX). This result will help physicians to determine the optimum needle thoracostomy (NT) puncture site in patients with a PTX. Materials and methods: All trauma patients who presented consecutively to A&E over a 12-month period were included. Among all the trauma patients with a chest CT (4204 patients), 160 were included in the final analysis. CWTs were measured at both sides and were compared in all subgroup of patients. Results: The average CWT for men on the 2nd ICS-MCL was 38 mm and for women was 52 mm; on the other hand, on the 5th ICS-MAL was 33 mm for men and 38 mm for women. On the 2nd ICS-MCL 17% of men and 48% of women; on the 5th ICS-MAL 13% of men and 33% of women would be inaccessible with a routine 5-cm catheter. Patients with trauma, subcutaneous emphysema and multiple rib fractures would have thicker CWT on the 2nd ICS-MCL. Patients with trauma, lung contusion, sternum fracture, subcutaneous emphysema and multiple rib fractures would have thicker CWT on the 5th ICS-MAL. Conclusions: This study confirms that a 5.0-cm catheter would be unlikely to access the pleural space in at least 1/3 of female and 1/10 of male Turkish trauma patients, regardless of the puncture site. If NT is needed, the 5th ICS-MAL is a better option for a puncture site with thinner CWT. (C) 2012 Elsevier Ltd. All rights reserved
The middle cerebral artery density and ratio for the diagnosis of acute ischaemic stroke in the Emergency Department
No full textPurpose Non-contrast computed tomography (ncCT) is the first-line imaging modality for acute ischaemic stroke diagnosis. Recognition of the early diagnostic signs of a stroke on computed tomography (CT) is crucial. The hyperdense middle cerebral artery (MCA) sign is one of these findings. We investigated the diagnostic utility of absolute MCA density (MCAD) in patients with acute MCA stroke confirmed with diffusion-weighted magnetic resonance imaging (dwMRI). Methods We retrospectively included all patients who presented to the Emergency Department with symptoms related to an acute stroke and confirmed with a dwMRI and ncCT to this diagnostic case-control study. An expert radiologist with more than four years of experience in neuroradiology re-evaluated all ncCT images. The evaluation of MCAD and ratio were measured on axial images in Hounsfield units (HU). Results We included 407 patients in our study (MCA infarction: 55%, n = 225; Control: 45%, n = 182). We calculated the threshold for the highest sensitivity (20%) and specificity (94%) as 49 HU with the Youden J index test for MCAD and as 1.1 for MCAD ratio (sensitivity 20% and specificity 95%). MCAD >49 HU or MCAD ratio >1.1 alone or joint use of MCAD >47 HU and MCAD ratio >1.1 are useful markers to confirm the diagnosis of MCA AIS with a specificity of at least 94%. Higher MCAD values are associated with larger infarction volumes. Conclusion MCAD and MCAD ratio can be used to identify patients who need early treatment, especially in situations where computed tomography angiogram or dwMRI are not readily available
Determination of the appropriate catheter length and place for needle thoracostomy by using computed tomography scans of pneumothorax patients
No full textIntroduction: The primary goal of this study was to compare the chest wall thicknesses (CWT) at the 2nd intercostal space (ICS) at the mid-clavicular line (MCL) and 5th ICS at the mid-axillary line (MAL) in a population of patients with a CT confirmed pneumothorax (PTX). This result will help physicians to determine the optimum needle thoracostomy (NT) puncture site in patients with a PTX. Materials and methods: All trauma patients who presented consecutively to A&E over a 12-month period were included. Among all the trauma patients with a chest CT (4204 patients), 160 were included in the final analysis. CWTs were measured at both sides and were compared in all subgroup of patients. Results: The average CWT for men on the 2nd ICS-MCL was 38 mm and for women was 52 mm; on the other hand, on the 5th ICS-MAL was 33 mm for men and 38 mm for women. On the 2nd ICS-MCL 17% of men and 48% of women; on the 5th ICS-MAL 13% of men and 33% of women would be inaccessible with a routine 5-cm catheter. Patients with trauma, subcutaneous emphysema and multiple rib fractures would have thicker CWT on the 2nd ICS-MCL. Patients with trauma, lung contusion, sternum fracture, subcutaneous emphysema and multiple rib fractures would have thicker CWT on the 5th ICS-MAL. Conclusions: This study confirms that a 5.0-cm catheter would be unlikely to access the pleural space in at least 1/3 of female and 1/10 of male Turkish trauma patients, regardless of the puncture site. If NT is needed, the 5th ICS-MAL is a better option for a puncture site with thinner CWT. (C) 2012 Elsevier Ltd. All rights reserved
Utility of cervical spinal and abdominal computed tomography in diagnosing occult pneumothorax in patients with blunt trauma: Computed tomographic imaging protocol matters
No full textBACKGROUND: Small pneumothoraces (PXs), which are not initially recognized with a chest x-ray film and diagnosed by a thoracic computed tomography (CT), are described as occult PX (OCPX). The objective of this study was to evaluate cervival spine (C-spine) and abdominal CT (ACT) for diagnosing OCPX and overt PX (OVPX). METHODS: All patients with blunt trauma who presented consecutively to the emergency department during a 26-months period were included. Among all the chest CTs (CCTs) (6,155 patients) conducted during that period, 254 scans were confirmed to have a true PX. The findings in their C-spine CT and ACT were compared with the findings in CCTs. RESULTS: Among these patients, 254 had a diagnosis of PX confirmed with CCT. OCPXs were identified on the chest computed tomographic scan of 128 patients (70.3%), whereas OVPXs were evident in 54 patients (29.7%). Computed tomographic imaging of the C-spine was performed in 74% of patients with OCPX and 66.7% of patients with OVPX trauma. Only 45 (35.2%) cases of OCPX and 42 (77.8%) cases of OVPX were detected by C-spine CT. ACT was performed in almost all patients, and 121 (95.3%) of 127 of these correctly identified an existing OCPX. Sensitivity of C-spine CT and ACT was 35.1% and 96.5%, respectively; specificity was 100% and 100%, respectively. CONCLUSION: Almost all OCPXs, regardless of intrathoracic location, could be detected by ACT or by combining C-spine and abdominal computed tomographic screening for patients. If the junction of the first and second vertebra is used as the caudad extent, C-spine CT does not have sufficient power to diagnose more than a third of the cases. (J Trauma Acute Care Surg. 2012;73:874-879. Copyright (C) 2012 by Lippincott Williams & Wilkins
Scan-Based Immersed Isogeometric Flow Analysis
No full textThis chapter reviews the work conducted by our team on scan-based immersed isogeometric analysis for flow problems. To leverage the advantageous properties of isogeometric analysis on complex scan-based domains, various innovations have been made: (i) A spline-based segmentation strategy has been developed to extract a geometry suitable for immersed analysis directly from scan data; (ii) A stabilized equal-order velocity-pressure formulation for the Stokes problem has been proposed to attain stable results on immersed domains; (iii) An adaptive integration quadrature procedure has been developed to improve computational efficiency; (iv) A mesh refinement strategy has been developed to capture small features at a priori unknown locations, without drastically increasing the computational cost of the scan-based analysis workflow. We review the key ideas behind each of these innovations, and illustrate these using a selection of simulation results from our work. A patient-specific scan-based analysis case is reproduced to illustrate how these innovations enable the simulation of flow problems on complex scan data.</p
Spinal Trauma is Never without Sin: A Tetraplegia Patient Presented Without any Symptoms
No full textSUMMARYSpinal cord injuries are amongst the most dangerous injuries, leading to high mortality and morbidity. Injured patients are occasionally faced with life-threatening complications and quality-of-life changing neurological deficits. Thoracic and cervical spinal segments are the most effected sites of injury and a wide range of complications including paraplegia, respiratory and cardiovascular compromise secondary to autonomic dysfunction or tetraplegia may ensue. We aim to draw attention to the progressive nature of the neurological deficits in a patient admitted asymptomatically. Also, we would like to discuss the importance of swift diagnosis and management in such patients. In asymptomatic patients in whom no fractures are diagnosed with CT scans, a neurological examination should be repeated several times to exclude any neurological injuries that were missed. MRI should be ordered in an emergency setting even though it is not frequently used as a diagnostic modality. This should be done especially in patients without any fractures on CT but with neurological signs
Comparison of Reservoir Simulation Techniques for Gas Reservoirs: Semi-Analytical Tank Flow Model Approach versus Finite Volume Solutions
No full textComparison of Reservoir Simulation Techniques for Gas Reservoirs: Semi-Analytical Tank Flow Model Approach versus Finite Volume SolutionsMehmet Onur Doğan a, Tayfun Jamalbayli* a, Mahammad Jamalbayov ba Middle East Technical University, Turkey b SOCAR "OilGasScientificResearchProject" Institute, Azerbaijan * Corresponding author: [email protected]: Numerical Model Development; Reservoir Simulation; Reservoir Modeling; Gas Condensate Reservoirs; Reservoir EngineeringThis research introduces a hybrid approach for reservoir simulation and explores its practical utility within the context of gas condensate reservoirs. The study assesses the strengths and weaknesses of this approach by comparing it to the conventional two-phase gas condensate model that employs the finite volume method. The methodology utilizes material balance equations to compute the average reservoir pressure and saturation. These computed values are subsequently applied across the reservoir using an analytical flow model, while taking into consideration well placements. This results in the development of a semi-analytical simulation approach. In addition, the finite volume model is also created as a benchmark model for comparative purposes, including IMPES and Fully Implicit solutions. The validity of the finite volume model is established through a comparison with Eclipse simulation software. The proposed simulation approach calculates pressure and saturation distributions that exhibit notable deviations from the results of the finite volume method, particularly struggling to accurately represent the region near the wellbore in terms of saturation. However, it excels in terms of computational efficiency and outperforms traditional methods in terms of speed. To enhance this approach, a future recommendation involves integrating the pressure distribution derived from the hybrid method with traditional saturation calculations. This integration has the potential to rectify discrepancies in saturation distribution while retaining the method's speed advantages. In summary, the hybrid reservoir simulation method presents a promising innovation for reservoir simulation techniques. The outcomes of the study provide a pathway to address these limitations, ultimately paving the way for a more efficient reservoir simulation tool
Ben Bende Değilim
No full textThe book includes memoirs of Mr. Yildirim who was author of the mentioned book also retired librarian. Author with beard and liken to different characters by people all the time so he shared his memoirs with dry humour
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