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摘要:We investigate the diagnostic reliability of differentiating between lipid-poor adrenal adenomas and metastatic adrenal tumors originating from hepatocellular carcinoma (HCC) using a routine dynamic CT protocol for liver imaging. Eighteen metastatic adrenal tumors originating from HCC and 13 lipid-poor adrenal adenomas were identified. Dynamic CT data were analyzed for CT attenuation of adrenal lesions before and after contrast administration. When a cutoff of 36 HU was set for adrenal lesions at pre-contrast attenuation, the sensitivity and specificity for the diagnosis of metastatic lesions were 94.4%and 92.3%, respectively. Attenuation criteria on pre-contrast CT may help optimize the differentiation between these lesions....
摘要: class="MsoNormal"> lang="EN-GB">Background: lang="EN-GB"> lang="EN-GB">There are recognised variations in the anatomical course of the cervical portion of the internal carotid artery. An aberrant vessel with direct contact to the pharyngeal wall could easily be injured during pharyngeal surgery or may appear as a pharyngeal pseudo mass. Previous anatomical studies predominantly involved older patients. The prevalence of such variations which are at risk of injury during pharyngeal surgery has thus not been established in a general patient population. lang="EN-GB"> lang="EN-GB">Material and Methods: lang="EN-GB"> lang="EN-GB">The course of the internal carotid artery in relation to the oro lang="EN-GB"> lang="EN-GB">and hypopharyngeal walls was retrospectively evaluated bilaterally by simple visual inspection and measurement of the smallest distance between the respective vessels and the adjacent mucosal surface of the pharyngeal wall in 138 con lang="EN-GB">secutive contrast-enhanced computed tomography scans of the neck. Results: lang="EN-GB"> lang="EN-GB">11/138 (7.9%) of patients demonstrated relevant cervical carotid artery aberrations, comprising medial kinking of a vessel with asymmetry of the adjacent pha lang="EN-GB">ryngeal lumen and/or an intimate submucous course in the pharyngeal wall with no identifiable separating fat plane. This prevalence increased with age. Simple visual inspection correlated well with the measurement of the smallest dis lang="EN-GB">tance between an artery and the pharyngeal wall, which was statistically significant (p < 0.0001). lang="EN-GB"> lang="EN-GB">Conclusions: lang="EN-GB"> lang="EN-US">The prevalence of about 8% in a general patient population is higher than previously recorded in anatomical studies. Preva lang="EN-US">lence increases with age. Otorhinolaryngologists should be aware of such variation as a risk factor for haemorrhagic complications during pharyngeal surgery and as a differential diagnosis of pharyngeal mass lesions, especially in older patients. Modern contrast-enhanced CT allows identification and characterisation of any surgically relevant variant va lang="EN-US">scular anatomy in the pre-operative work-up. lang="EN-GB">

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摘要: class="MsoNormal" style="text-align:justify;"> lang="EN-US" style="font-family:Verdana;">Estimated LBW could be used to determine the contrast material dose and rate during MDCT. lang="EN-GB" style="font-family:Verdana;"> The aim of this study is to test the accuracy of a technique for estimation of lean body weight (LBW) from a single multi-detector row computed tomographic (MDCT) abdominal image, using a bioelectrical body composition analyzer scale as the reference standard. CT images of 21 patients with previously measured LBW (mLBW) were processed using computer-assisted, vendor-specific software (Advantage Windows 4.2; GE Healthcare, Inc). For each transverse image, a fat-fraction was automatically measured as the number of fat pixels (- lang="EN-GB" style="font-family:Verdana;">200 to - lang="EN-GB" style="font-family:Verdana;">50 HU) divided by the total number of pixels having an attenuation value ≥- lang="EN-GB" style="font-family:Verdana;">200 HU. Estimated LBW (eLBW) of five single contiguous sections was calculated in each of three abdominal regions (upper abdomen, mid abdomen and pelvis) by multiplying TBW by (1 fat-fraction). Bland-Altman plot with limits of agreement was used to assess agreement between mLBW and eLBW. The mean mLBW for all patients was 56 kg (range, 39 - 75 kg). Mean differences and limits of agreement between mLBW and eLBW measurements for the upper abdomen, mid abdomen and pelvis reported were - lang="EN-GB" style="font-family:Verdana;">8.9 kg (- lang="EN-US" style="font-family:Verdana;">25.6 kg, +7.5 kg lang="EN-GB" style="font-family:Verdana;">), - lang="EN-GB" style="font-family:Verdana;">10.6 kg (- lang="EN-US" style="font-family:Verdana;">27.7 kg, +6.4 kg lang="EN-GB" style="font-family:Verdana;">), and +0.5 kg (- lang="EN-US" style="font-family:Verdana;">12.8 kg, +13.8 lang="EN-GB" style="font-family:Verdana;"> kg) respectively. eLBW deriving directly from a transverse CT image of the pelvis can accurately predict mLBW lang="EN-US"> style="font-family:Verdana;">.

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摘要:The present study utilized a porcine model for qualitative and quantitative assessment of the diagnostic quality of non-contrast abdominal computed tomography (CT) images generated by Adaptive Statistical Iterative Reconstruction (ASIR, GE Healthcare, Waukesha, Wisconsin, USA), Model-Based Iterative Reconstruction (GE company name VEO), and conventional Filtered back projection (FBP) technique. Methods: Multiple CT whole-body scans of a freshly euthanized pig carcass were performed on a 64-slice GE CT scanner at varying noise indices (5, 10, 15, 20, 30, 37, 40, 45), and with three different algorithms (VEO, FBP, and ASIR at 30%, 50%, and 70% levels of ASIR-FBP blending). Abdominal CT images were reviewed and scored in a blinded and randomized manner by two board-certified abdominal radiologists. The task was to evaluate the clarity of the images according to a rubric involving edge sharpness, presence of artifact, anatomical clarity (assessed at four regions), and perceived diagnostic acceptability. This amounted to seven criteria, each of which was graded on a scale of 1 to 5. A weighted formula was used to calculate a composite score for each scan. Results: VEO outperforms ASIR and FBP by an average of 0.5 points per the scoring system used (p < 0.05). Above a threshold noise index of 30, diagnostic acceptability is lost by all algorithms, and there is no diagnostic advantage to increasing the dose beyond a noise index of 10. Between a noise index of 25 - 30, VEO retains diagnostic acceptability, as opposed to ASIR and FBP which lose acceptability above noise index of 25. Conclusion: Model-based iterative reconstruction provides superior image quality and anatomical clarity at reduced radiation dosages, supporting the routine use of this technology, particularly in pediatric abdominal CT scans....
摘要: style="text-align:justify;"> style="line-height:2;font-family:Verdana;">Background: Detection of malignant liver mass is very important for the treatment modalities. Objective: The purpose of the present study was to establish the usefulness of CT scan in the diagnosis of malignant hepatic mass. Methodology: This cross sectional study was carried out in the Department of Radiology and Imaging at Mymensingh Medical College Hospital (MMCH), Mymensingh, Banghabandhu Sheikh Mujib Medical University (BSMMU), Dhaka and Dhaka Medical College Hospital (DMCH), Dhaka during the period of 1st January 2006 to 31st December 2007. Patients admitted in the Department of Medicine and Department of Hepatobiliary of MMCH, BSMMU, and DMCH with the clinical diagnosis of fever, abdominal pain, anorexia, nausea/vomiting, loss of appetite, jaundice, weight loss and ascites were selected as study population. CT scan and histopathology were performed to all the patients. Result: A total number of 50 patients were recruited for this study. Mean age of all patients was 51.28 ± 14 years with a range of 17 year to 78 years. Among all patients 28 had multiple lesion, of them 71.4% was malignant and 28.6% was benign. On the other side 22 patients had solitary lesion, of them 36.4% was malignant and 63.6% was benign (p < 0.05). Sensitivity of CT to diagnose malignant lesion was 96.4%, specificity 86.4%, accuracy 92%, positive predictive value 90% and negative predictive value 95%. Conclusion: CT is a useful diagnostic tool for the detection of malignant hepatic masses.
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摘要:The constrained total variation minimization has been developed successfully for image reconstruction in computed tomography. In this paper, the block component averaging and diagonally-relaxed orthogonal projection methods are proposed to incorporate with the total variation minimization in the compressed sensing framework. The convergence of the algorithms under a certain condition is derived. Examples are given to illustrate their convergence behavior and noise performance....
摘要: class="MsoNormal"> lang="EN-US" style="font-family:Verdana;font-size:12px;">Objective: lang="EN-US"> style="font-family:Verdana;font-size:12px;"> The higher risk and fatality of cardiovascular disease in subjects with homozygous familial hypercholesterolemia warrants early screening. Computed tomography angiography is the most promising method at present as a reliable and reproducible noninvasive diagnostic test of cardiovascular disease. We aimed to describe the 64-slice multidetector computed tomography coronary angiography findings of new cases with homozygous familial hypercholesterolemia. style="font-family:Verdana;font-size:12px;">Methods: style="font-family:Verdana;font-size:12px;"> Four patients with homozygous familial hypercholesterolemia (2 female and 2 male) with mean age of 23 lang="EN-US"> lang="EN-US" style="font-family:Verdana;font-size:12px;">± lang="EN-US"> lang="EN-US" style="font-family:Verdana;font-size:12px;">9 years were included. Mean plasma total and LDL cholesterol were 654 lang="EN-US"> lang="EN-US" style="font-family:Verdana;font-size:12px;">± lang="EN-US"> lang="EN-US" style="font-family:Verdana;font-size:12px;">75 mg/dl and 609 lang="EN-US"> lang="EN-US" style="font-family:Verdana;font-size:12px;">± lang="EN-US"> lang="EN-US"> style="font-family:Verdana;font-size:12px;">76 mg/dl. Tomography examinations were performed using a 64-row MDCT-CA system (Brilliance Computed Tomography scanner, Philips Healthcare). style="font-family:Verdana;font-size:12px;">Results: style="font-family:Verdana;font-size:12px;">All patients presented calcified and mixed atherosclerotic plaques in the ascending aorta near the origin of the coronary arteries. More extensive atherosclerosis was found in Case 1 and Case 2 than in other cases. Case 3 has mild atherosclerosis and Case 4 had normal coronaries but plaques in aorta. In addition lang="EN-US" style="font-family:Verdana;font-size:12px;">, lang="EN-US"> style="font-family:Verdana;font-size:12px;"> we detected myocardial bridging in left anterior descending artery of 2 cases, calcified plaques in postero-lateral branch artery, and calcification in non-coronary sinus in others. style="font-family:Verdana;font-size:12px;"> Conclusion: style="font-family:Verdana;font-size:12px;"> Multidetector computed tomography coronary angiography is a useful, non-invasive tool for detecting early aortic and coronary atherosclerosis in homozygous familial hypercholesterolemia subjects and may be the choice of imaging for most of such subjects. lang="EN-US">

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摘要: class="MsoNormal"> lang="EN-US">Scimitar Syndrome is a congenital condition resulting in anomalous pulmonary venous drainage from the lung into the inferior vena cava. It is often associated with cardiac and pulmonary abnormalities, both which are determinants in the severity and timing of presentation. True incidence of this condition is unknown and likely to be significantly underes lang="EN-US">timated as many patients remain asymptomatic through adult life. The increase in availability and use of medical imag lang="EN-US">ing suggests that more asymptomatic and subacute cases will be detected. The management in those with the delayed presentation of this condition is debated, however the mainstay of therapy remains medical. lang="EN-US">

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摘要:The present study aimed to evaluate using the whole milk as alternative oral contrast for the as-sessment of gastrointestinal CT enterography. Fifty patients undergo (18 female and 32 male) aged from 21 to 79 years (mean 45 years) undergo abdominal CT at the department of diagnostic radiology of King Abdulaziz University Hospital. They receive 1 - 1.5 liter whole milk. Siemens SOMATOM definition CT Scan Machine with 64 slices and dual source was utilized to image all pa-tients in research population group where iodinated oral contrast media was replaced by a whole milk available in the local market. Patients were scanned as per the routine protocol used for CT Abdomen at KAUH-CT Unit: Helical Mode with 0.7 Pitch was performed on all paints in supine po-sition using a 16-detector row scanner (Bright Speed S, General Electric-Milwaukee Wisconsin, USA). The following parameters were applied: collimation of 16 × 0.625 (1.25 - 3.75) mm, pitch of 3, Slice thickness: 5 mm, gantry rotation time of 400 mAs, tube voltage of 120 KV and scan time 11.05 second. The images of all cases were reviewed by two qualified radiologists. Conclusion: The present study suggested that whole milk was found to be an effective alternative negative contrast for the assessment of the jejunum, ileum and terminal ileum in CT enterography. It was excellent for gastric imaging and we recommended replacing milk as negative oral contrast since it is available and cost effective. Further research to be conducted with modified milk drinking timing for better large bowel distention....
摘要:Acute abdomen is a common presentation in emergency medicine. It represents 5% to 10% of all Emergency Department (ED) visits. Diagnosis by imaging includes digital X-ray unit, sonography (US) unit and computed tomography (CT) equipment. During the last years, a trend towards increased use of computed tomography in patients with acute abdomen can be seen. Additionally, patient with severe claustrophobic often cannot tolerate MR scanner. The aim of the present study was to investigate the possibility of optimizing Helical CT parameters in the protocol and emphasize the CT features of selected cases of disorders related acute abdominal complain at the Emergency Department both in general and in a number of selected conditions (Urolithiasis, Aortic Aneurysm Rupture and acute cholecystitis). According to this work findings, non-contrast CT after ultrasound is diagnostic modality for patients with urinary stones in the Emergency Department. Contrast-enhanced CT was highly sensitive for acute aortic syndrome and therefore the CT imaging protocols must be adjusted in order to minimize dose from radiation....
摘要: class="MsoNormal" style="text-align:justify;"> lang="EN-US"> style="font-family:Verdana;">Pilomatrixoma is an uncommon benign tumor of matrix cells of hair follicles that rarely involves eyelids. Here we present a case of 4-year-old girl who was brought to hospital with swelling in the left upper eyelid which increased gradually in 1 year. Computed tomography revealed calcified soft tissue mass. The mass was excised successfully and sent for histopathological examination that showed encapsulated tumor composed of eosinophilic ghost cells and basophilic cells suggestive of pilomatrixoma.

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摘要:

Introduction: Corneal thickness measurement is an indirect assessment of the physiological corneal function in human eye. This value, especially in the central area, is an important data for clinical diagnosis, treatment and monitoring of anterior segment pathologies. There are several technologies for non-invasively measuring corneal thickness like optical coherence tomography (OCT). However, there is little information available describing the effect of contact lens induced corneal swelling in OCT measures. The purpose of this study was to evaluate the repeatability of OCT corneal pachymetry in eyes with and without contact lens induced corneal swelling. Material and Methods: This study included five visits over one week in six healthy subjects: baseline and after sleeping with four different CL of +0.50 D, +2.00 D, +5.00 D and +8.00 D (Acuvue 2, Johnson & Johnson Vision Care) on four different days. Corneal pachymetry OCT 3D (Topcon) were measured three consecutive times during each visit. Besides, this measurement was repeated in 12 meridians (Scans #1 to #12), between 0 style="font-family:'Times New Roman','serif';font-size:10pt;"> style="font-size:10.5pt;font-family:宋体;">°and 165 style="font-family:'Times New Roman','serif';font-size:10pt;"> style="font-size:10.5pt;font-family:宋体;">°with 15 style="font-family:'Times New Roman','serif';font-size:10pt;"> style="font-size:10.5pt;font-family:宋体;">° intervals. Results: Corneal pachymetry was significant different between before and after contact lens wear (p < 0.001 ANOVA). High repeatability was found without corneal swelling [Coefficient of variation (CV) = 0.68% p = 0.93] and with corneal swelling [CL -0.50 D (CV = 0.78% p = 0.95; 590 ± 46 μm CI 95% 548 to 596), with CL + 2.00 D (CV = 0.72% p = 0.97; 601 ± 46 μm CI 95% 595 to 607), with CL + 5.00 D (CV = 0.78% p = 0.66; 608 ± 50 μm CI 95% 601 to 615) and with CL + 8.00 D (CV = 0.77% p = 0.97; 607 ± 44 μm CI 95% 601 to 613)]. There were no differences (p = 1.00) in central corneal thickness along the 12 scans corneal [Scan #0 (593 ± 50 μm CI 95% 582 to 603), #1 (592 ± 50 μm CI 95% 581 to 603), #2 (591 ± 50 μm IC 95% 580 to 602), #3 (590 ± 49 μm CI 95% 579 to 600), #4 (590 ± 50 μm CI 95% 579 to 600), #5 (591 ± 50 μm CI 95% 581 to 602), #6 (590 ± 51 μm CI 95% 580 to 601), #7 (589 ± 50 μm CI 95% 578 to 600), #8 (590 ± 50 μm CI 95% 579 to 600), #9 (589 ± 50 μm CI 95% 579 to 600), #10 (592 ± 50 μm CI 95% 581 to 602) and #11 (591 ± 50 μm CI 95% 580 to 601). Conclusions: 3D OCT showed a high repeatability (CV < 1%) to measure central thickness in corneas with and without contact lens induced corneal swelling. This technology presents advantages over other clinical devices used to measure corneal thickness and could be the “gold standard” for future clinical studies and clinical practice for eye care practitioners.

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摘要: class="MsoNormal"> lang="EN-US" style="font-family:Verdana;">Purpose: lang="EN-US" style="font-family:Verdana;">To evaluate a new miniature optical navigation system for CT-guided liver interventions. lang="EN-US"> lang="EN-US" style="font-family:Verdana;">Material and Methods: lang="EN-US" style="font-family:Verdana;"> A two-center, prospective study was performed with four interventional radiologists. A total of lang="EN-US"> lang="EN-US" style="font-family:Verdana;">20 patients had CT-guided liver biopsy or ablation interventions utilizing lang="EN-US"> lang="EN-US"> style="font-family:Verdana;">the CT-Guide style="white-space:nowrap;">? style="font-family:Verdana;"> navigation system (ActiViews Inc., w:st="on"> w:st="on"> style="font-family:Verdana;">Wakefield style="font-family:Verdana;">, w:st="on"> style="font-family:Verdana;">MA style="font-family:Verdana;">) between July 2011 and December 2011. The navigation system consists of a self-adhesive patientsticker printed with coincident colored and radio-opaque reference markers, a miniature disposable video camera that clips on and off an interventional instrument, and software loaded on a computer to display the navigation information. The primary end point was the frequency of a satisfactory instrument lang="EN-US"> lang="EN-US" style="font-family:Verdana;">position for the intended intervention. lang="EN-US"> lang="EN-US" style="font-family:Verdana;">Results: lang="EN-US"> lang="EN-US" style="font-family:Verdana;">The cohort consisted of 13 males and 7 females with an average age of 63.1 years (range of 38 to 80). lang="EN-US"> lang="EN-US" style="font-family:Verdana;">Most of the patients, 70%, lang="EN-US"> lang="EN-US"> style="font-family:Verdana;">underwent CT-guided liver biopsy while the remainder had CT-guided ablation therapy. The average lesion size was w:st="on" unitname="cm" sourcevalue="3.1" hasspace="True" negative="False" numbertype="1" tcsc="0"> style="font-family:Verdana;">3.1 cm style="font-family:Verdana;"> (range of 1.1 - lang="EN-US"> lang="EN-US" style="font-family:Verdana;">6.9 lang="EN-US"> lang="EN-US" style="font-family:Verdana;">cm). All lang="EN-US"> lang="EN-US" style="font-family:Verdana;">of the interventions, regardless of lesion size, met the primary end point lang="EN-US"> lang="EN-US" style="font-family:Verdana;">of satisfactory instrument positioning. There were no device-related or...
摘要:Background: Cardiac output can be estimated during retrospectively gated CT coronary angiography by anatomically determining left ventricular volumes; prospective triggering to minimize radiation precludes this methodology. We propose an alternative method for cardiac output estimation based on preclinical models suggesting that cardiac output may be inversely related to contrast washout from the aortic root during timing bolus scanning, as measured by peak aortic root contrast attenuation. Methods: 34 patients had CT coronary angiography timing bolus performed with 20 ml iodixanol at 5.5 ml/s followed by 20 ml normal saline at 5.5 ml/s through an 18-Ga antecubital catheter. Peak aortic root contrast attenuation was correlated to cardiac output calculated by echocardiography using heart rate stroke volume from biplane Simpson's method.Results: Mean age was 58 ± 13 years; body surface area, 2.0 ± 0.5 m2. 53% were women. Stroke volume, cardiac output and cardiac index were 67 ± 19 ml, 4.5 ± 1.6 L/min, and 2.2 ± 0.7 L/min/m2, respectively. Peak aortic root contrast attenuation was 207 ± 46 HU and correlated to cardiac output and cardiac index with r = –0.64, p < 0.0001 and r = –0.55, p < 0.001, respectively. Regression analysis estimates cardiac output = –0.02 peak aortic root contrast attenuation +9.1. Conclusion: This novel method for cardiac output estimation by CTCA appears feasible. The CT physiologic parameters using the timing test-bolus data moderately correlated with echocardiographic assessment of cardiac output. The calculation of cardiac output adds important hemodynamic data to anatomic information provided by CTCA, and further development of this method may preserve assessment of left ventricular performance in prospective triggering....
摘要: style="text-align:justify;"> style="line-height:2;font-family:Verdana;">Purpose: The clinical significance of newly identified left atrial anatomic abnormalities (LAAA)— accessory appendages, diverticula, septal pouches—by multidetector CT (MDCT) remains unclear. Similar anatomical outpouchings, i.e., the left atrial appendage, have been associated with cardioembolisms and arrhythmia. To test the hypothesis that LAAA are also associated with increased risk of these events, we performed a retrospective analysis to examine the association of LAAA in patients undergoin style="line-height:2;font-family:Verdana;">g CT with embolic events and arrhythmia. Methods: 242 patients (mean age 56 SD 12 years, 41% female) were selected who had CT coronary angiography performed with 64-row MDCT between 2007 and 2012 if complete clinical history records were available. CT images were independently reviewed for the presence of LAAA. Association of cerebrovascular accident (CVA) or transient ischemic attack (TIA), atrial fibrillation, and palpitations to LAAA was calculated using odds ratios (OR) with 95% confidence interval (CI) and Fisher's exact test. Results: After adjusting for age, sex, hypertension, dyslipidemia and diabetes via multiple logistic regression, patients with accessory appendages are more likely to have reported palpitations (OR: 1.80; CI: 1.03 - 3.16). Patients with diverticula and septal pouches are significantly older than those without these abnormalities (p = 0.01 and p = 0.02, respectively). Septal pouches are associated with diabetes (OR: 2.29; 95%CI: 1.15 - 4.54). Conclusions: Accessory left atrial appendages are associated with palpitations. Patients with septal pouches and diverticula are significantly older than those patients without these anatomic abnormalities, suggesting age dependency of these findings. None of these anatomic abnormalities were associated with thromboembolic events after adjustment for potentially confounding comorbidities.
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摘要:AIM: CT scanning is a widely utilised effective diagnostic tool. We aimed to establish whether patients are adequately informed prior to undergoing CT investigations. Methods: All adult patients with mental capacity attending the department for a CT study over a week period were invited to fill out a brief questionnaire prior to their scan. Results: 57 patients returned completed questionnaires. Overall 23% of patients were unsure or incorrect about the type of scan scheduled. Of patients attending with a new condition, 46% of them did not know their provisional diagnosis. Only 32 % of patients had insight into how a CT scan worked. This was taken to mean that the patient had included some reference to either x-rays, radiation or cross sectional imaging. Only 23% of patients were aware of potential complications of CT scans. Conclusion: Although written consent prior to CT scan is probably a step too far in providing patients with relevant risks/benefits of their investigation, we propose all patients undergoing CT have prior access to a written information sheet should they wish to be further informed regarding their procedure....
摘要: class="MsoNormal"> lang="EN-US">A 12 lang="EN-US">- lang="EN-US">year-old boy presented to his primary care physician with a painful lump at the angle of the left mandible after being kicked in the jaw during a soccer game. Over the next 2 months the lesion became progressively firmer and fine needle aspiration was attempted. Results were non-diagnostic. Panorex examination revealed a calcified mass contiguous with the left angle of the mandible. Considerations were bony callus secondary to trauma versus a calcified hematoma. A maxillofacial CT showed multiple diffuse craniofacial osseous lesions including the clinically suspected region at the left angle of the mandible. Imaging findings were consistent with multiple craniofacial osteomas and workup for Gard lang="EN-US">ner Syndrome was initiated. Genetic testing was subsequently positive for Familial Adenomatous Polyposis. lang="EN-US">

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摘要:Making a confident diagnosis is a complex task for a specific form of interstitial lung disease and providing appropriate management in an attempt to achieve normalization of the disease can put up an alarming process for the clinicians. A set of diffuse and restrictive lung diseases incorporate with idiopathic interstitial pneumonias, showing inflammation and fibrosis of the interstitium due to parenchymal damage. High-resolution computed tomography (HRCT) has magnified the diagnostic standpoint in stepwise identification and classified various patterns in the evaluation of interstitial lung disease. The aim of our review is to elaborate clinical, radiographic and typical and atypical HRCT findings of idiopathic interstitial pneumonias by correlating with its differential diagnosis. Idiopathic pulmonary fibrosis is the most predominant idiopathic interstitial pneumonias and its diagnosis needs to omit all other well-known causes of interstitial lung diseases. According to the 2011 evidence-based guidelines, usual interstitial pneumonia can be diagnosed by HRCT when all criteria are fulfilled. Non-specific interstitial pneumonia is distinguished by bilateral patchy ground-glass opacities and irregular linear/reticular opacities. Respiratory bronchiolitis associated-interstitial lung disease and desquamative interstitial pneumonia show centrolobular nodules and ground-glass opacities as imaging patterns. Cryptogenic organizing pneumonia consists of patchy peripheral or peribronchial consolidations, while ground-glass opacities with tendency for migration, which is evolving to fibrosis, in acute interstitial pneumonia. Lymphoid interstitial pneumonia and idiopathic pleuro-parenchymal fibroelastosis are classified under rare idiopathic interstitial pneumonias. HRCT images help radiologists in diagnosis and mapping specific patterns of idiopathic interstitial pneumonias. This article reviews the stages of evolution in HRCT features for idiopathic interstitial pneumonias....
摘要: class="MsoNormal"> lang="EN-US">We present a case report of a 65-year-old woman who underwent resection of a chest wall tumor. In contrast with computed tomography, the tumor exhibited hypervascularity and was fed from the 9th intercostals artery. Histologically, the tumor was diagnosed as a cellular variant of solitary fibrous tumor of the pleura, with branching “staghorn” vessels and hypervascularity. The tumor thus resembled a chest wall hemangiopericytoma. prefix = o />

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摘要:Phase imaging coupled to micro-tomography acquisition has emerged as a powerful tool to investigate specimens in a non-destructive manner. While the intensity data can be acquired and recorded, the phase information of the signal has to be “retrieved” from the data modulus only. Phase retrieval is an ill-posed non-linear problem and regularization techniques including a priori knowledge are necessary to obtain stable solutions. Several linear phase recovery methods have been proposed and it is expected that some limitations resulting from the linearization of the direct problem will be overcome by taking into account the non-linearity of the phase problem. To achieve this goal, we propose and evaluate a non-linear algorithm for in-line phase micro-tomography based on an iterative Landweber method with an analytic calculation of the Fréchet derivative of the phase-intensity relationship and of its adjoint. The algorithm was applied in the projection space using as initialization the linear mixed solution. The efficacy of the regularization scheme was evaluated on simulated objects with a slowly and a strongly varying phase. Experimental data were also acquired at ESRF using a propagation-based X-ray imaging technique for the given pixel size 0.68 μm. Two regularization scheme were considered: first the initialization was obtained without any prior on the ratio of the real and imaginary parts of the complex refractive index and secondly a constant a priori value was assumed on src="Edit_9f28813b-7867-452b-9c07-1eaab14f8914.bmp" alt="" />?. The tomographic central slices of the refractive index decrement were compared and numerical evaluation was performed. The non-linear method globally decreases the reconstruction errors compared to the linear algorithm and is achieving better reconstruction results if no prior is introduced in the initialization solution. For in-line phase micro-tomography, this non-linear approach is a new and interesting method in biomedical studies where the exact value of the a priori ratio is not known....
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