BACKGROUND Multilocular thymic cyst(MTC)is a rare mediastinal lesion which is considered to occur in the process of acquired inflammation.It is usually characterized by well-defined cystic density and is filled with t...BACKGROUND Multilocular thymic cyst(MTC)is a rare mediastinal lesion which is considered to occur in the process of acquired inflammation.It is usually characterized by well-defined cystic density and is filled with transparent liquid.CASE SUMMARY We report on a 39-year-old male with a cystic-solid mass in the anterior mediastinum.Computer tomography(CT)imaging showed that the mass was irregular with unclear boundaries.After injection of contrast agent,there was a slight enhancement of stripes and nodules.According to CT findings,it was diagnosed as thymic cancer.CONCLUSION After surgery,MTC accompanied by bleeding and infection was confirmed by pathological examination.The main lesson of this case was that malignant thymic tumor and MTC of the anterior mediastinum sometimes exhibit similar CT findings.Caution is necessary in clinical work to avoid misdiagnosis.展开更多
AIMTo measure optic nerve sheath diameters (ONSD) in different locations by computer tomography (CT) and to recommend the best location for cases when ONSD is used for intracranial pressure monitoring.METHODSIn a pros...AIMTo measure optic nerve sheath diameters (ONSD) in different locations by computer tomography (CT) and to recommend the best location for cases when ONSD is used for intracranial pressure monitoring.METHODSIn a prospective cohort study, CT data of 300 healthy adults were analyzed (600 eyes). In all cases, the CT investigation was performed at the Emergency Department because of the various conditions that proved not to be connected with ophthalmological or neurological pathology. The ONSD were measured at 3 mm and 8 mm distance from the globe, and 3 mm from the anterior opening of the optic canal. The correlation analysis was performed with gender, age, and ethnic background.RESULTSThe right/left ONSD are 4.94±1.51/5.17±1.34 mm at 3 mm, 4.35±0.76/4.45±0.62 mm at 8 mm from the globe, and 3.55±0.82/3.65±0.7 mm at 3 mm from the optic canal. No significant differences correlated with gender of the patients, their age, and ethnic background were found.CONCLUSIONIn healthy persons, the ONSD varies from 5.17±1.34 mm to 3.55±0.82 mm in different locations within the intraorbital space. The most stable results with lesser standard deviation can be obtained if it is measured 8-10 mm from the globe.展开更多
BACKGROUND Esophagojejunal anastomotic leakage(EJAL)is a serious and potentially crucial complication of total gastrectomy and represents the major cause of postoperative death,with a mortality rate of up to 50%.Howev...BACKGROUND Esophagojejunal anastomotic leakage(EJAL)is a serious and potentially crucial complication of total gastrectomy and represents the major cause of postoperative death,with a mortality rate of up to 50%.However,treatment remains challenging and controversial.We report here the case of a patient whose intrathoracic EJAL was successfully treated with computer tomography(CT)-guided negative pressure drainage treatment.CASE SUMMARY A 69-year-old male patient complained of difficulty swallowing within the last six months.He was diagnosed with esophagogastric junction carcinoma,Siewert II,cT3N0M0 stage II.Total gastrectomy and Roux-en-Y esophagojejunostomy were performed.High fever,left chest pain and dyspnea appeared on postoperative day 5,and EJAL was confirmed by CT,gastroscopy and oral blue-dimethylene tests.Conservative treatment measures were applied immediately,including antibiotics,nasojejunal tubes,and repeated thoracic puncture and drainage under ultrasound guidance.However,without sufficient and effective drainage,the thoracic infection and systemic condition continued to deteriorate.With the cooperation of multiple departments,percutaneous CT-guided drainage(24 Fr 7 mm)in the thoracic cavity was successfully placed near the anastomotic leakage.Because of continuous negative pressure suction,the infection symptoms were effectively controlled and the general situation gradually recovered.Subsequent follow-up examination showed that the patient was in good condition.CONCLUSION Negative pressure drainage via CT may represent an effective minimally invasive approach to treating intrathoracic EJAL.展开更多
BACKGROUND: It has been proved that brain electrical activity mapping (BEAM) and transcranial Doppler (TCD) detection can reflect the function of brain cell and its diseased degree of infant patients with moderat...BACKGROUND: It has been proved that brain electrical activity mapping (BEAM) and transcranial Doppler (TCD) detection can reflect the function of brain cell and its diseased degree of infant patients with moderate to severe hypoxic-ischemic encephalopathy (HIE). OBJECTIVE: To observe the abnormal results of HIE at different degrees detected with BEAM and TCD in infant patients, and compare the detection results at the same time point between BEAM, TCD and computer tomography (CT) examinations. DESIGN : Contrast observation SETTING: Departments of Neuro-electrophysiology and Pediatrics, Second Affiliated Hospital of Qiqihar Medical College. PARTICIPANTS: Totally 416 infant patients with HIE who received treatment in the Department of Newborn Infants, Second Affiliated Hospital of Qiqihar Medical College during January 2001 and December 2005. The infant patients, 278 male and 138 female, were at embryonic 37 to 42 weeks and weighing 2.0 to 4.1 kg, and they were diagnosed with CT and met the diagnostic criteria of HIE of newborn infants compiled by Department of Neonatology, Pediatric Academy, Chinese Medical Association. According to diagnostic criteria, 130 patients were mild abnormal, 196 moderate abnormal and 90 severe abnormal. The relatives of all the infant patients were informed of the experiment. METHOOS: BEAM and TCD examinations were performed in the involved 416 infant patients with HIE at different degrees with DYD2000 16-channel BEAM instrument and EME-2000 ultrasonograph before preliminary diagnosis treatment (within 1 month after birth) and 1,3,6,12 and 24 months after birth, and detected results were compared between BEAM, TCD and CT examinations. MAIN OUTCOME MEASURES: Comparison of detection results of HIE at different time points in infant patients between BEAM. TCD and CT examinations. RESULTS: All the 416 infant patients with HIE participated in the result analysis. (1) Comparison of the detected results in infant patients with mild HIE at different time points after birth between BEAM, TCD and CT examinations: BEAM examination showed that the recovery was delayed, and the abnormal rate of BEAM examination was significantly higher than that of CT examination 1 and 3 months after birth [55.4%(72/130)vs. 17.0% (22/130 ),x^2=41.66 ;29.2% ( 38/130 ) vs. 6.2% ( 8/130 ), x^2=23.77, P 〈 0.01 ], exceptional patients had mild abnormality and reached the normal level in about 6 months. TCD examination showed that the disease condition significantly improved and infant patients with HIE basically recovered 1 or 2 months after birth, while CT examination showed that infant patients recovered 3 or 4 months after birth. (2) Comparison of detection results of infant patients with moderate HIE at different time points between BEAM, TCD and CT examinations: The abnormal rate of BEAM examination was significantly higher than that of CT examination 1,3,6 and 12 months after birth [90.8% (178/196),78.6% (154/196),x^2=4.32,P 〈 0.05;64.3% (126/196),43.9% (86/196) ,x^2=16.44 ;44.9% (88/196) ,22.4% (44/196),x^2=22.11 ;21.4% (42/196), 10.2% (20/196),x^2=9.27, P 〈 0.01]. BEAM examination showed that there was still one patient who did not completely recovered in the 24^th month due to the relatives of infant patients did not combine the treatment,. TCD examination showed that the abnormal rate was 23.1%(30/196)in the 1^st month after birth, and all the patients recovered to the normal in the 3^rd month after birth, while CT examination showed that mild abnormality still existed in the 24^th month after birth (1.0% ,2/196). (3) Comparison of detection results of infant patients with severe HIE at different time points between BEAM, TCD and CT examinations: The abnormal rate of BEAM examination was significantly higher than that of CT examination in the 1^st, 3^rd, 6^th and 12^th months after birth[86.7% (78/90),44.4% (40/90),x^2=35.53;62.2% (56/90),31.1% (28/90),x^2=17.51 ;37.8% (34/90),6.7% (6/90), x^2=27.14, P 〈 0.01]. BEAM examination showed that mild abnormality still existed in 4 infant patients in the 24^th month after birth. TCD examination showed that the abnormal rate was 11.1% (10/90) in the 3^rd month after birth, and all the infant patients recovered in the 6^th month after birth. CT examination showed that the abnormal rate was 6.7%(6/90) in the 12^th month after birth, and all of infant patients recovered to the normal in the 24^th month after birth.CONCLUSION : BEAM is the direct index to detect brain function of infant patients with HIE, and positive reaction is still very sensitive in the tracking detection of convalescent period. The positive rate of morphological reaction in CT examination is superior to that in TCD examination, and the positive rate is very high in the acute period of HIE in examination.展开更多
BACKGROUND This study aimed to describe the findings of double superior mesenteric veins(SMVs),a rare anatomical variation,on multidetector computer tomography(MDCT)and magnetic resonance imaging(MRI)images.CASE SUMMA...BACKGROUND This study aimed to describe the findings of double superior mesenteric veins(SMVs),a rare anatomical variation,on multidetector computer tomography(MDCT)and magnetic resonance imaging(MRI)images.CASE SUMMARY We describe the case of a 34-year-old male,who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis.MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein(SMV),the double SMVs.CONCLUSION The double SMVs are a congenital abnormality without potential clinical manifestation.Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury.展开更多
Background The diagnosis of Parkinson’s disease is presently based on non-specific symptoms. However, radionuclide dopamine transporters imaging can provide specific diagnostic tool for Parkinson’s disease. This st...Background The diagnosis of Parkinson’s disease is presently based on non-specific symptoms. However, radionuclide dopamine transporters imaging can provide specific diagnostic tool for Parkinson’s disease. This study was designed to investigate the effects of imaging of dopamine transporters with 99mTc-TRODAT-1 in early diagnosis or differential diagnosis of Parkinson’s disease.Methods Nine normal monkeys were used to establish N-methyl-4-phenyl-1, 2, 3, 6-tetra-hydropyridine (MPTP) hemi-Parkinsonian animal models, and they were subjected to imaging. Twenty-nine patients with Parkinson’s disease, 12 age-matched healthy volunteers, and 18 age-matched patients with Parkinson’s syndrome were investigated. Single photon emission computer tomography (SPECT) was performed 3 hours after intravenous injection of 740 MBq 99mTc-TRODAT-1. Striatum specific uptake of 99mTc-TRODAT-1 was calculated according to the ratio of striatum (ST) to cerebellum (CB)in dopamine transporters uptake.Results In normal monkeys, bilateral ratio of ST/CB was 2.34±0.41. After the injection of MPTP, uptake rate of 99mTc-TRODAT-1 at damaged region was much lower than that at the contralateral region, resulting in a significant difference in the ratio of ST/CB (right: ST/CB=1.73±0.35; left: ST/CB=1.90±0.30), especially in hemi-Parkinsonian model monkeys (right: ST/CB=1.29±0.17; left: ST/CB=1.80±0.33). The ratios of ST/CB were 1.57±0.17 and 1.61±0.14 for the right and left respectively in the healthy volunteers, 1.04±0.29 and 1.06±0.30 in the age-matched patients with Parkinson’s disease, and 1.56±0.17 and 1.59±0.18 in the age-matched patients with Parkinson’s disease syndrome. A significant difference was noted between group of Parkinson’s disease, normal controls and Parkinson’s disease syndrome. Conclusion The results suggest that 99mTc-TRODAT-1 dopamine transporters SPECT has clinical application value in early diagnosis or differential diagnosis of Parkinson’s disease.展开更多
BACKGROUND The level of Ki-67 expression has served as a prognostic factor in gastric cancer.The quantitative parameters based on the novel dual-layer spectral detector computed tomography(DLSDCT)in discriminating the...BACKGROUND The level of Ki-67 expression has served as a prognostic factor in gastric cancer.The quantitative parameters based on the novel dual-layer spectral detector computed tomography(DLSDCT)in discriminating the Ki-67 expression status are unclear.AIM To investigate the diagnostic ability of DLSDCT-derived parameters for Ki-67 expression status in gastric carcinoma(GC).METHODS Dual-phase enhanced abdominal DLSDCT was performed preoperatively in 108 patients with gastric adenocarcinoma.Primary tumor monoenergetic CT attenuation value at 40-100 kilo electron volt(kev),the slope of the spectral curve(λ_(HU)),iodine concentration(IC),normalized IC(nIC),effective atomic number(Z^(eff))and normalized Z^(eff)(nZ^(eff))in the arterial phase(AP)and venous phase(VP)were retrospectively compared between patients with low and high Ki-67 expression in gastric adenocarcinoma.Spearman’s correlation coefficient was used to analyze the association between the above parameters and Ki-67 expression status.Receiver operating characteristic(ROC)curve analysis was performed to compare the diagnostic efficacy of the statistically significant parameters between two groups.RESULTS Thirty-seven and 71 patients were classified as having low and high Ki-67 expression,respectively.CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),and Z^(eff)-related parameters were significantly higher,but IC-related parameters were lower in the group with low Ki-67 expression status than the group with high Ki-67 expression status,and other analyzed parameters showed no statistical difference between the two groups.Spearman’s correlation analysis showed that CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),Z^(eff),and n Z^(eff) exhibited a negative correlation with Ki-67 status,whereas IC and nIC had positive correlation with Ki-67 status.The ROC analysis demonstrated that the multi-variable model of spectral parameters performed well in identifying the Ki-67 status[area under the curve(AUC)=0.967;sensitivity 95.77%;specificity 91.89%)].Nevertheless,the differentiating capabilities of singlevariable model were moderate(AUC value 0.630-0.835).In addition,the nZ_(VP)^(eff) and nIC_(VP)(AUC 0.835 and 0.805)showed better performance than CT_(40 kev-VP),CT_(70 kev-VP) and CT_(100 kev-VP)(AUC 0.630,0.631 and 0.662)in discriminating the Ki-67 status.CONCLUSION Quantitative spectral parameters are feasible to distinguish low and high Ki-67 expression in gastric adenocarcinoma.Z^(eff) and IC may be useful parameters for evaluating the Ki-67 expression.展开更多
One factor that limits development of fundamental research on the infuence of coke microstructure on its strength is the difculty in quantifying the way that microstructure is both classifed and distributed in three d...One factor that limits development of fundamental research on the infuence of coke microstructure on its strength is the difculty in quantifying the way that microstructure is both classifed and distributed in three dimensions.To support such fundamental studies,this study evaluated a novel volumetric approach for classifying small(approx.450μm^(3))blocks of coke microstructure from 3D computed tomography scans.An automated process for classifying microstructure blocks was described.It is based on Landmark Multi-Dimensional Scaling and uses the Bhattacharyya metric and k-means clustering.The approach was evaluated using 27 coke samples across a range of coke with diferent properties and reliably identifed 6 ordered class of coke microstructure based on the distribution of voxel intensities associated with structural density.The lower class(1–2)subblocks tend to be dominated by pores and thin walls.Typically,there is an increase in wall thickness and reduced pore sizes in the higher classes.Inert features are also likely to be seen in higher classes(5–6).In general,this approach provides an efcient automated means for identifying the 3D spatial distribution of microstructure in CT scans of coke.展开更多
Medical Image Fusion is the synthesizing technology for fusing multi-modal medical information using mathematical procedures to generate better visual on the image content and high-quality image output.Medical image f...Medical Image Fusion is the synthesizing technology for fusing multi-modal medical information using mathematical procedures to generate better visual on the image content and high-quality image output.Medical image fusion represents an indispensible role infixing major solutions for the complicated medical predicaments,while the recent research results have an enhanced affinity towards the preservation of medical image details,leaving color distortion and halo artifacts to remain unaddressed.This paper proposes a novel method of fusing Computer Tomography(CT)and Magnetic Resonance Imaging(MRI)using a hybrid model of Non Sub-sampled Contourlet Transform(NSCT)and Joint Sparse Representation(JSR).This model gratifies the need for precise integration of medical images of different modalities,which is an essential requirement in the diagnosing process towards clinical activities and treating the patients accordingly.In the proposed model,the medical image is decomposed using NSCT which is an efficient shift variant decomposition transformation method.JSR is exercised to extricate the common features of the medical image for the fusion process.The performance analysis of the proposed system proves that the proposed image fusion technique for medical image fusion is more efficient,provides better results,and a high level of distinctness by integrating the advantages of complementary images.The comparative analysis proves that the proposed technique exhibits better-quality than the existing medical image fusion practices.展开更多
BACKGROUND Lupus mesenteric vasculitis(LMV)is a serious condition that may occur as an acute manifestation of gastrointestinal(GI)involvement and is not easily diagnosed by physicians.Delayed diagnosis and treatment o...BACKGROUND Lupus mesenteric vasculitis(LMV)is a serious condition that may occur as an acute manifestation of gastrointestinal(GI)involvement and is not easily diagnosed by physicians.Delayed diagnosis and treatment of LMV may lead to rapid disease progression and can be life threatening.CASE SUMMARY A previously healthy 27-year-old woman presented with abdominal pain following a history of fatigue and consumption of cold water.Laboratory invest-igations,physical examinations,and enhanced abdominal computed tomography(CT)suggested systemic lupus erythematosus complicated by LMV.She received treatments,such as GI decompression,somatostatin,glucocorticoids,and immu-nosuppressants,and was evaluated using color ultrasonography.Twenty days later,the patient reported no stomach discomfort and was able to consume semi-liquid food.Laboratory investigations showed that inflammatory factors decreased to normal levels and complement levels increased slightly.One year after discharged,she recovered with methylprednisolone being tapered to 4 mg per day,mycophenolate mofetil to 0.75 g bid,and hydroxychloroquine to 0.2 g bid;however,only C3 complement level was slightly below the normal level.CONCLUSION Early diagnosis of LMV is essential for successful treatment;this depends on a combination of clinical manifestations,laboratory investigations,and imaging findings.Enhanced CT is preferred,but ultrasonography can be used for prompt screening and follow-up.展开更多
Objective To compare the similarities and differences of early CT manifestations of three types of viral pneumonia induced by SARS-CoV-2(COVID-19),SARS-CoV(SARS)and MERS-CoV(MERS)using a systemic review.Methods Electr...Objective To compare the similarities and differences of early CT manifestations of three types of viral pneumonia induced by SARS-CoV-2(COVID-19),SARS-CoV(SARS)and MERS-CoV(MERS)using a systemic review.Methods Electronic database were searched to identify all original articles and case reports presenting chest CT features for adult patients with COVID-19,SARS and MERS pneumonia respectively.Quality of literature and completeness of presented data were evaluated by consensus reached by three radiologists.Vote-counting method was employed to include cases of each group.Data of patients’manifestations in early chest CT including lesion patterns,distribution of lesions and specific imaging signs for the three groups were extracted and recorded.Data were compared and analyzed using SPSS 22.0.Results A total of 24 studies were included,composing of 10 studies of COVID-19,5 studies of MERS and 9 studies of SARS.The included CT exams were 147,40,and 122 respectively.For the early CT features of the 3 pneumonias,the basic lesion pattern with respect to"mixed ground glass opacity(GGO)and consolidation,GGO mainly,or consolidation mainly"was similar among the 3 groups(χ^2=7.966,P>0.05).There were no significant differences on the lesion distribution(χ^2=13.053,P>0.05)and predominate involvement of the subpleural area of bilateral lower lobes(χ^2=4.809,P>0.05)among the 3 groups.The lesions appeared more focal in COVID-19 pneumonia at early phase(χ^2=23.509,P<0.05).The proportions of crazy-paving pattern(χ^2=23.037,P<0.001),organizing pneumonia pattern(P<0.05)and pleural effusions(P<0.001)in COVID-19 pneumonia were significantly lower than the other two.Although rarely shown in the early CT findings of all three viral pneumonias,the fibrotic changes were more frequent in SARS than COVID-19 and MERS(χ^2=6.275,P<0.05).For other imaging signs,only the MERS pneumonia demonstrated tree-in-buds,cavitation,and its incidence rate of interlobular or intralobular septal thickening presented significantly increased as compared to the other two pneumonia(χ^2=22.412,P<0.05).No pneumothorax,pneumomediastinum and lymphadenopathy was present for each group.Conclusions Imaging findings on early stage of these three coronavirus pneumonias showed similar basic lesion patterns,including GGO and consolidation,bilateral distribution,and predominant involvement of the subpleural area and the lower lobes.Early signs of COVID-19 pneumonia showed less severity of inflammation.Early fibrotic changes appeared in SARS only.MERS had more severe inflammatory changes including cavitation and pleural effusion.The differences may indicate the specific pathophysiological processes for each coronavirus pneumonia.展开更多
BACKGROUND Thrombectomy and anatomical anastomosis(TAA)has long been considered the optimal approach to portal vein thrombosis(PVT)in liver transplantation(LT).However,TAA and the current approach for non-physiologica...BACKGROUND Thrombectomy and anatomical anastomosis(TAA)has long been considered the optimal approach to portal vein thrombosis(PVT)in liver transplantation(LT).However,TAA and the current approach for non-physiological portal reconstructions are associated with a higher rate of complications and mortality in some cases.AIM To describe a new choice for reconstructing the portal vein through a posterior pancreatic tunnel(RPVPPT)to address cases of unresectable PVT.METHODS Between August 2019 and August 2021,245 adult LTs were performed.Forty-five(18.4%)patients were confirmed to have PVT before surgery,among which seven underwent PV reconstruction via the RPVPPT approach.We retrospectively analyzed the surgical procedure and postoperative complications of these seven recipients that underwent PV reconstruction due to PVT.RESULTS During the procedure,PVT was found in all the seven cases with significant adhesion to the vascular wall and could not be dissected.The portal vein proximal to the superior mesenteric vein was damaged in one case when attempting thrombolectomy,resulting in massive bleeding.LT was successfully performed in all patients with a mean duration of 585 min(range 491-756 min)and mean intraoperative blood loss of 800 mL(range 500-3000 mL).Postoperative complications consisted of chylous leakage(n=3),insufficient portal venous flow to the graft(n=1),intra-abdominal hemorrhage(n=1),pulmonary infection(n=1),and perioperative death(n=1).The remaining six patients survived at 12-17 mo follow-up.CONCLUSION The RPVPPT technique might be a safe and effective surgical procedure during LT for complex PVT.However,follow-up studies with large samples are still warranted due to the relatively small number of cases.展开更多
The motion of a lure in water is investigated experimentally and numerically.The lure motion in water of apassing water tank is observed,and the periodic motion is found.From the Fourier analysis,it is found that the ...The motion of a lure in water is investigated experimentally and numerically.The lure motion in water of apassing water tank is observed,and the periodic motion is found.From the Fourier analysis,it is found that the frequency with the largest amplitude in the lateral direction depends on the lip width of the lure.To understand the lure dynamics,a numerical simulation of the flow field around the lure is performed.The shape is measured using an X-ray computer tomography and converted into a voxel model.From visualization,it is found that vortex sheds from its lip correspond to the vibration frequency of the lure.展开更多
Objective: Evaluation of peripheral arterial disease with 64-detector multi-slice CT angiography (MDCT- A) and comparison of the results with the results of digital subtraction angiography (DSA), a standard reference....Objective: Evaluation of peripheral arterial disease with 64-detector multi-slice CT angiography (MDCT- A) and comparison of the results with the results of digital subtraction angiography (DSA), a standard reference. Materials and Method: The written informed consent of the patients and ethics committee approval were obtained. The retrospective study group consisted of 28 patients with a diagnosis of peripheral arterial disease. Using 64-MDCT-A, the arterial tree of the lower extremity was evaluated for the presence of steno-occlusive lesions that might have led to luminal stenosis. The diagnostic reliability of 64-MDCT- A was calculated and compared with that of DSA. Findings: In the segment-based analysis, the sensitivity, specificity, and reliability rates of 64-MDCT angiography in determining significant stenoses were 97.7%, 97%, and 97.3%, respectively. The Kappa co-efficiency for compatibility between 64-MDCT-A and DSA methods in grading stenosis was calculated as 0.896展开更多
A middle-aged male patient with a right orbital comminuted fracture underwent computer tomography scanning, and a three-dimensional finite element model of the eyes and relevant tissues was established. Optic nerve st...A middle-aged male patient with a right orbital comminuted fracture underwent computer tomography scanning, and a three-dimensional finite element model of the eyes and relevant tissues was established. Optic nerve stress in a hyperbaric oxygen environment was simulated and analyzed by changing the elastic modulus and external pressure of the skull at the damage side. Results showed that stress maximized at the contact site of the optic nerve and the eyeball in the damaged and intact eye orbits. Optic nerve stress at the damaged orbit significantly increased; however, stress in the intact orbit only slightly changed with decreased elastic modulus of the skull while external pressure remained unchanged. Maximum optic nerve stress increased in the damaged and intact side, along with increased external pressure, while elastic modulus remained unchanged. These experimental findings suggested that the optic nerve was compressed under hyperbaric oxygen and optic nerve stress was greater in the damaged orbit than in the intact orbit.展开更多
Pancreatic fat accumulation has been described with various terms including pancreatic lipomatosis, pancreatic steatosis, fatty replacement, fatty infiltration, fatty pancreas, lipomatous pseudohypertrophy and nonalco...Pancreatic fat accumulation has been described with various terms including pancreatic lipomatosis, pancreatic steatosis, fatty replacement, fatty infiltration, fatty pancreas, lipomatous pseudohypertrophy and nonalcoholic fatty pancreas disease. It has been reported to be associated with type 2 diabetes mellitus, acute pancreatitis, pancreatic cancer and the formation of pancreatic fistula. The real incidence of this condition is still unknown. We report a case of pancreatic steatosis in a non-obese female patient initially diagnosed with a mass in the head of the pancreas. Magnetic resonance imaging(MRI) was carried out to define the characteristics of the pancreatic mass. MRI confirmed the diagnosis of fat pancreas. Enlarged pancreas is not always a cancer, but pancreatic steatosis is characterized by pancreatic enlargement. MRI could give a definite diagnosis of pancreatic steatosis or cancer.展开更多
Over the past twenty years, improvements in neuroimaging have greatly improved the ability to diagnose cerebral venous sinus thrombosis, as well as isolated cortical venous thrombosis. Neuroimaging allows for variatio...Over the past twenty years, improvements in neuroimaging have greatly improved the ability to diagnose cerebral venous sinus thrombosis, as well as isolated cortical venous thrombosis. Neuroimaging allows for variations to be detected in the cortical vein and venous sinus. Diagnosis of thromboses in the venous system should not depend entirely on angiography of undeveloped veins or venous sinus. Currently, the combination of magnetic resonance imaging and magnetic resonance venography is the gold standard for diagnosing cerebral venous sinus thrombosis, rather than digital subtraction angiography. This article summarizes clinical manifestations, results from computed tomography and magnetic resonance imaging in two cases of isolated cortical venous thrombosis, analyzed relevant literature, and discussed the clinical and imaging characteristics of isolated cortical venous thromboses.展开更多
BACKGROUND Peliosis hepatis(PH)is a rare benign lesion of vascular origin with a pathological characteristic of multiple blood-filled cavities in the liver parenchyma.It is commonly misdiagnosed due to its lack of spe...BACKGROUND Peliosis hepatis(PH)is a rare benign lesion of vascular origin with a pathological characteristic of multiple blood-filled cavities in the liver parenchyma.It is commonly misdiagnosed due to its lack of specificity in clinical presentation and laboratory test results.Herein,a case of a patient with PH who was misdiagnosed with hepatic echinococcosis before operation to remove the lesions was analyzed,with an emphasis on the computed tomography and magnetic resonance imaging characteristics of PH.CASE SUMMARY We outline the case of a 40-year-old Chinese female who was admitted with aggravated abdominal pain with fever for 1 wk.Ultrasound examination at the local hospital indicated hepatic echinococcosis.However,discordance between imaging diagnosis,clinical history and laboratory examinations in our hospital.Subsequently,the patient was pathologically confirmed as having PH-like changes,which recurred 1 year after operation removal of the lesion.CONCLUSION Our objective is to highlight the imaging diagnostic value of PH.展开更多
Background Safe placement of the screws is a critical aspect of trans-pedicle internal fixation, and little information on in vivo morphology of the cervical vertebrae pedicle measured with imaging methods is availabl...Background Safe placement of the screws is a critical aspect of trans-pedicle internal fixation, and little information on in vivo morphology of the cervical vertebrae pedicle measured with imaging methods is available. The aim of this study was to measure the dimensions of cervical vertebrae C3 to C7 and provide screw length, screw diameter and tilt angle for clinical cervical vertebra trans-pedicle internal fixation. Methods Thirty Chinese men and women underwent high-speed spiral computed tomography measurements to obtain data for C3 to C7, and the morphology of the cervical vertebra pedicles was reconstructed. Results Reconstructed computer tomography image data revealed that: (1) pedicle sponge width increased incrementally from C3 to C7, (2) pedicle depth was similar for C3 to C7, (3) pedicle angle decreased incrementally from 47.20~ to 33.76~ for' C3 to C7, and (4) pedicle point to midline distance was similar for C3 to C7. There were no statistical differences in morphological data between the right and the left side. Men had statistically larger values than women for all morphological parameters. Conclusions Reconstructed computed tomography images can provide useful data for clinical cervical vertebra trans-pedicle internal fixation. The individual measurement of cervical vertebra pedicles is recommended for safe placement of trans-vertebra pedicle screws.展开更多
Morphological changes within the porous architecture of laboratory scale zero valent iron (ZVI) permeable reactive barriers (PRBs), after exposure to different groundwater conditions, have been quantified experime...Morphological changes within the porous architecture of laboratory scale zero valent iron (ZVI) permeable reactive barriers (PRBs), after exposure to different groundwater conditions, have been quantified experimentally for different ZVI/sand ratios (10%, 50% and 100%, W/W) with the aim of inferring porosity changes in field barriers. Column studies were conducted to simulate interaction with different water chemistries, a synthetic groundwater, acidic drainage and deionised (DI) water as control. Morphological changes, in terms of pore size and distribution, were measured using X-ray computed tomography (CT). CT image analysis revealed significant morphological changes in columns treated with different water chemistries. For example, 100% ZVI (W/W) columns had a higher frequency of small pores (0.6 mm) was observed in ZVI grains reacted with typical groundwater, resulting in a porosity of 27%, compared to 32% when exposed to DI water. In comparison, ZVI grains treated with the acidic drainage had higher porosity (44%) and larger average pore size (2.8 mm). 10% ZVI PRB barrier material had the highest mean porosity (56%) after exposure to any water chemistry whilst 100% ZVI (W/W) columns always had the lowest (34%) with the 50% ZVI (W/W) in between (40%). These results agree with previously published PRB field data and simultaneously conducted geochemical monitoring and mass balance calculation, indicating that both the geochemical and hydraulic environment of the PRB play an important role in determining barrier lifespan. This study suggests that X-ray CT image analysis is a powerful tool for studying the detailed inter pores between ZVI grains within PRBs.展开更多
文摘BACKGROUND Multilocular thymic cyst(MTC)is a rare mediastinal lesion which is considered to occur in the process of acquired inflammation.It is usually characterized by well-defined cystic density and is filled with transparent liquid.CASE SUMMARY We report on a 39-year-old male with a cystic-solid mass in the anterior mediastinum.Computer tomography(CT)imaging showed that the mass was irregular with unclear boundaries.After injection of contrast agent,there was a slight enhancement of stripes and nodules.According to CT findings,it was diagnosed as thymic cancer.CONCLUSION After surgery,MTC accompanied by bleeding and infection was confirmed by pathological examination.The main lesson of this case was that malignant thymic tumor and MTC of the anterior mediastinum sometimes exhibit similar CT findings.Caution is necessary in clinical work to avoid misdiagnosis.
文摘AIMTo measure optic nerve sheath diameters (ONSD) in different locations by computer tomography (CT) and to recommend the best location for cases when ONSD is used for intracranial pressure monitoring.METHODSIn a prospective cohort study, CT data of 300 healthy adults were analyzed (600 eyes). In all cases, the CT investigation was performed at the Emergency Department because of the various conditions that proved not to be connected with ophthalmological or neurological pathology. The ONSD were measured at 3 mm and 8 mm distance from the globe, and 3 mm from the anterior opening of the optic canal. The correlation analysis was performed with gender, age, and ethnic background.RESULTSThe right/left ONSD are 4.94±1.51/5.17±1.34 mm at 3 mm, 4.35±0.76/4.45±0.62 mm at 8 mm from the globe, and 3.55±0.82/3.65±0.7 mm at 3 mm from the optic canal. No significant differences correlated with gender of the patients, their age, and ethnic background were found.CONCLUSIONIn healthy persons, the ONSD varies from 5.17±1.34 mm to 3.55±0.82 mm in different locations within the intraorbital space. The most stable results with lesser standard deviation can be obtained if it is measured 8-10 mm from the globe.
基金Supported by National Natural Science Foundation of China,No.H0306/81100254.
文摘BACKGROUND Esophagojejunal anastomotic leakage(EJAL)is a serious and potentially crucial complication of total gastrectomy and represents the major cause of postoperative death,with a mortality rate of up to 50%.However,treatment remains challenging and controversial.We report here the case of a patient whose intrathoracic EJAL was successfully treated with computer tomography(CT)-guided negative pressure drainage treatment.CASE SUMMARY A 69-year-old male patient complained of difficulty swallowing within the last six months.He was diagnosed with esophagogastric junction carcinoma,Siewert II,cT3N0M0 stage II.Total gastrectomy and Roux-en-Y esophagojejunostomy were performed.High fever,left chest pain and dyspnea appeared on postoperative day 5,and EJAL was confirmed by CT,gastroscopy and oral blue-dimethylene tests.Conservative treatment measures were applied immediately,including antibiotics,nasojejunal tubes,and repeated thoracic puncture and drainage under ultrasound guidance.However,without sufficient and effective drainage,the thoracic infection and systemic condition continued to deteriorate.With the cooperation of multiple departments,percutaneous CT-guided drainage(24 Fr 7 mm)in the thoracic cavity was successfully placed near the anastomotic leakage.Because of continuous negative pressure suction,the infection symptoms were effectively controlled and the general situation gradually recovered.Subsequent follow-up examination showed that the patient was in good condition.CONCLUSION Negative pressure drainage via CT may represent an effective minimally invasive approach to treating intrathoracic EJAL.
文摘BACKGROUND: It has been proved that brain electrical activity mapping (BEAM) and transcranial Doppler (TCD) detection can reflect the function of brain cell and its diseased degree of infant patients with moderate to severe hypoxic-ischemic encephalopathy (HIE). OBJECTIVE: To observe the abnormal results of HIE at different degrees detected with BEAM and TCD in infant patients, and compare the detection results at the same time point between BEAM, TCD and computer tomography (CT) examinations. DESIGN : Contrast observation SETTING: Departments of Neuro-electrophysiology and Pediatrics, Second Affiliated Hospital of Qiqihar Medical College. PARTICIPANTS: Totally 416 infant patients with HIE who received treatment in the Department of Newborn Infants, Second Affiliated Hospital of Qiqihar Medical College during January 2001 and December 2005. The infant patients, 278 male and 138 female, were at embryonic 37 to 42 weeks and weighing 2.0 to 4.1 kg, and they were diagnosed with CT and met the diagnostic criteria of HIE of newborn infants compiled by Department of Neonatology, Pediatric Academy, Chinese Medical Association. According to diagnostic criteria, 130 patients were mild abnormal, 196 moderate abnormal and 90 severe abnormal. The relatives of all the infant patients were informed of the experiment. METHOOS: BEAM and TCD examinations were performed in the involved 416 infant patients with HIE at different degrees with DYD2000 16-channel BEAM instrument and EME-2000 ultrasonograph before preliminary diagnosis treatment (within 1 month after birth) and 1,3,6,12 and 24 months after birth, and detected results were compared between BEAM, TCD and CT examinations. MAIN OUTCOME MEASURES: Comparison of detection results of HIE at different time points in infant patients between BEAM. TCD and CT examinations. RESULTS: All the 416 infant patients with HIE participated in the result analysis. (1) Comparison of the detected results in infant patients with mild HIE at different time points after birth between BEAM, TCD and CT examinations: BEAM examination showed that the recovery was delayed, and the abnormal rate of BEAM examination was significantly higher than that of CT examination 1 and 3 months after birth [55.4%(72/130)vs. 17.0% (22/130 ),x^2=41.66 ;29.2% ( 38/130 ) vs. 6.2% ( 8/130 ), x^2=23.77, P 〈 0.01 ], exceptional patients had mild abnormality and reached the normal level in about 6 months. TCD examination showed that the disease condition significantly improved and infant patients with HIE basically recovered 1 or 2 months after birth, while CT examination showed that infant patients recovered 3 or 4 months after birth. (2) Comparison of detection results of infant patients with moderate HIE at different time points between BEAM, TCD and CT examinations: The abnormal rate of BEAM examination was significantly higher than that of CT examination 1,3,6 and 12 months after birth [90.8% (178/196),78.6% (154/196),x^2=4.32,P 〈 0.05;64.3% (126/196),43.9% (86/196) ,x^2=16.44 ;44.9% (88/196) ,22.4% (44/196),x^2=22.11 ;21.4% (42/196), 10.2% (20/196),x^2=9.27, P 〈 0.01]. BEAM examination showed that there was still one patient who did not completely recovered in the 24^th month due to the relatives of infant patients did not combine the treatment,. TCD examination showed that the abnormal rate was 23.1%(30/196)in the 1^st month after birth, and all the patients recovered to the normal in the 3^rd month after birth, while CT examination showed that mild abnormality still existed in the 24^th month after birth (1.0% ,2/196). (3) Comparison of detection results of infant patients with severe HIE at different time points between BEAM, TCD and CT examinations: The abnormal rate of BEAM examination was significantly higher than that of CT examination in the 1^st, 3^rd, 6^th and 12^th months after birth[86.7% (78/90),44.4% (40/90),x^2=35.53;62.2% (56/90),31.1% (28/90),x^2=17.51 ;37.8% (34/90),6.7% (6/90), x^2=27.14, P 〈 0.01]. BEAM examination showed that mild abnormality still existed in 4 infant patients in the 24^th month after birth. TCD examination showed that the abnormal rate was 11.1% (10/90) in the 3^rd month after birth, and all the infant patients recovered in the 6^th month after birth. CT examination showed that the abnormal rate was 6.7%(6/90) in the 12^th month after birth, and all of infant patients recovered to the normal in the 24^th month after birth.CONCLUSION : BEAM is the direct index to detect brain function of infant patients with HIE, and positive reaction is still very sensitive in the tracking detection of convalescent period. The positive rate of morphological reaction in CT examination is superior to that in TCD examination, and the positive rate is very high in the acute period of HIE in examination.
文摘BACKGROUND This study aimed to describe the findings of double superior mesenteric veins(SMVs),a rare anatomical variation,on multidetector computer tomography(MDCT)and magnetic resonance imaging(MRI)images.CASE SUMMARY We describe the case of a 34-year-old male,who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis.MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein(SMV),the double SMVs.CONCLUSION The double SMVs are a congenital abnormality without potential clinical manifestation.Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury.
文摘Background The diagnosis of Parkinson’s disease is presently based on non-specific symptoms. However, radionuclide dopamine transporters imaging can provide specific diagnostic tool for Parkinson’s disease. This study was designed to investigate the effects of imaging of dopamine transporters with 99mTc-TRODAT-1 in early diagnosis or differential diagnosis of Parkinson’s disease.Methods Nine normal monkeys were used to establish N-methyl-4-phenyl-1, 2, 3, 6-tetra-hydropyridine (MPTP) hemi-Parkinsonian animal models, and they were subjected to imaging. Twenty-nine patients with Parkinson’s disease, 12 age-matched healthy volunteers, and 18 age-matched patients with Parkinson’s syndrome were investigated. Single photon emission computer tomography (SPECT) was performed 3 hours after intravenous injection of 740 MBq 99mTc-TRODAT-1. Striatum specific uptake of 99mTc-TRODAT-1 was calculated according to the ratio of striatum (ST) to cerebellum (CB)in dopamine transporters uptake.Results In normal monkeys, bilateral ratio of ST/CB was 2.34±0.41. After the injection of MPTP, uptake rate of 99mTc-TRODAT-1 at damaged region was much lower than that at the contralateral region, resulting in a significant difference in the ratio of ST/CB (right: ST/CB=1.73±0.35; left: ST/CB=1.90±0.30), especially in hemi-Parkinsonian model monkeys (right: ST/CB=1.29±0.17; left: ST/CB=1.80±0.33). The ratios of ST/CB were 1.57±0.17 and 1.61±0.14 for the right and left respectively in the healthy volunteers, 1.04±0.29 and 1.06±0.30 in the age-matched patients with Parkinson’s disease, and 1.56±0.17 and 1.59±0.18 in the age-matched patients with Parkinson’s disease syndrome. A significant difference was noted between group of Parkinson’s disease, normal controls and Parkinson’s disease syndrome. Conclusion The results suggest that 99mTc-TRODAT-1 dopamine transporters SPECT has clinical application value in early diagnosis or differential diagnosis of Parkinson’s disease.
文摘BACKGROUND The level of Ki-67 expression has served as a prognostic factor in gastric cancer.The quantitative parameters based on the novel dual-layer spectral detector computed tomography(DLSDCT)in discriminating the Ki-67 expression status are unclear.AIM To investigate the diagnostic ability of DLSDCT-derived parameters for Ki-67 expression status in gastric carcinoma(GC).METHODS Dual-phase enhanced abdominal DLSDCT was performed preoperatively in 108 patients with gastric adenocarcinoma.Primary tumor monoenergetic CT attenuation value at 40-100 kilo electron volt(kev),the slope of the spectral curve(λ_(HU)),iodine concentration(IC),normalized IC(nIC),effective atomic number(Z^(eff))and normalized Z^(eff)(nZ^(eff))in the arterial phase(AP)and venous phase(VP)were retrospectively compared between patients with low and high Ki-67 expression in gastric adenocarcinoma.Spearman’s correlation coefficient was used to analyze the association between the above parameters and Ki-67 expression status.Receiver operating characteristic(ROC)curve analysis was performed to compare the diagnostic efficacy of the statistically significant parameters between two groups.RESULTS Thirty-seven and 71 patients were classified as having low and high Ki-67 expression,respectively.CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),and Z^(eff)-related parameters were significantly higher,but IC-related parameters were lower in the group with low Ki-67 expression status than the group with high Ki-67 expression status,and other analyzed parameters showed no statistical difference between the two groups.Spearman’s correlation analysis showed that CT_(40 kev-VP),CT_(70 kev-VP),CT_(100 kev-VP),Z^(eff),and n Z^(eff) exhibited a negative correlation with Ki-67 status,whereas IC and nIC had positive correlation with Ki-67 status.The ROC analysis demonstrated that the multi-variable model of spectral parameters performed well in identifying the Ki-67 status[area under the curve(AUC)=0.967;sensitivity 95.77%;specificity 91.89%)].Nevertheless,the differentiating capabilities of singlevariable model were moderate(AUC value 0.630-0.835).In addition,the nZ_(VP)^(eff) and nIC_(VP)(AUC 0.835 and 0.805)showed better performance than CT_(40 kev-VP),CT_(70 kev-VP) and CT_(100 kev-VP)(AUC 0.630,0.631 and 0.662)in discriminating the Ki-67 status.CONCLUSION Quantitative spectral parameters are feasible to distinguish low and high Ki-67 expression in gastric adenocarcinoma.Z^(eff) and IC may be useful parameters for evaluating the Ki-67 expression.
基金the Australian Coal Industry's Research Program(ACARP)-Grant Number C29073.
文摘One factor that limits development of fundamental research on the infuence of coke microstructure on its strength is the difculty in quantifying the way that microstructure is both classifed and distributed in three dimensions.To support such fundamental studies,this study evaluated a novel volumetric approach for classifying small(approx.450μm^(3))blocks of coke microstructure from 3D computed tomography scans.An automated process for classifying microstructure blocks was described.It is based on Landmark Multi-Dimensional Scaling and uses the Bhattacharyya metric and k-means clustering.The approach was evaluated using 27 coke samples across a range of coke with diferent properties and reliably identifed 6 ordered class of coke microstructure based on the distribution of voxel intensities associated with structural density.The lower class(1–2)subblocks tend to be dominated by pores and thin walls.Typically,there is an increase in wall thickness and reduced pore sizes in the higher classes.Inert features are also likely to be seen in higher classes(5–6).In general,this approach provides an efcient automated means for identifying the 3D spatial distribution of microstructure in CT scans of coke.
文摘Medical Image Fusion is the synthesizing technology for fusing multi-modal medical information using mathematical procedures to generate better visual on the image content and high-quality image output.Medical image fusion represents an indispensible role infixing major solutions for the complicated medical predicaments,while the recent research results have an enhanced affinity towards the preservation of medical image details,leaving color distortion and halo artifacts to remain unaddressed.This paper proposes a novel method of fusing Computer Tomography(CT)and Magnetic Resonance Imaging(MRI)using a hybrid model of Non Sub-sampled Contourlet Transform(NSCT)and Joint Sparse Representation(JSR).This model gratifies the need for precise integration of medical images of different modalities,which is an essential requirement in the diagnosing process towards clinical activities and treating the patients accordingly.In the proposed model,the medical image is decomposed using NSCT which is an efficient shift variant decomposition transformation method.JSR is exercised to extricate the common features of the medical image for the fusion process.The performance analysis of the proposed system proves that the proposed image fusion technique for medical image fusion is more efficient,provides better results,and a high level of distinctness by integrating the advantages of complementary images.The comparative analysis proves that the proposed technique exhibits better-quality than the existing medical image fusion practices.
文摘BACKGROUND Lupus mesenteric vasculitis(LMV)is a serious condition that may occur as an acute manifestation of gastrointestinal(GI)involvement and is not easily diagnosed by physicians.Delayed diagnosis and treatment of LMV may lead to rapid disease progression and can be life threatening.CASE SUMMARY A previously healthy 27-year-old woman presented with abdominal pain following a history of fatigue and consumption of cold water.Laboratory invest-igations,physical examinations,and enhanced abdominal computed tomography(CT)suggested systemic lupus erythematosus complicated by LMV.She received treatments,such as GI decompression,somatostatin,glucocorticoids,and immu-nosuppressants,and was evaluated using color ultrasonography.Twenty days later,the patient reported no stomach discomfort and was able to consume semi-liquid food.Laboratory investigations showed that inflammatory factors decreased to normal levels and complement levels increased slightly.One year after discharged,she recovered with methylprednisolone being tapered to 4 mg per day,mycophenolate mofetil to 0.75 g bid,and hydroxychloroquine to 0.2 g bid;however,only C3 complement level was slightly below the normal level.CONCLUSION Early diagnosis of LMV is essential for successful treatment;this depends on a combination of clinical manifestations,laboratory investigations,and imaging findings.Enhanced CT is preferred,but ultrasonography can be used for prompt screening and follow-up.
文摘Objective To compare the similarities and differences of early CT manifestations of three types of viral pneumonia induced by SARS-CoV-2(COVID-19),SARS-CoV(SARS)and MERS-CoV(MERS)using a systemic review.Methods Electronic database were searched to identify all original articles and case reports presenting chest CT features for adult patients with COVID-19,SARS and MERS pneumonia respectively.Quality of literature and completeness of presented data were evaluated by consensus reached by three radiologists.Vote-counting method was employed to include cases of each group.Data of patients’manifestations in early chest CT including lesion patterns,distribution of lesions and specific imaging signs for the three groups were extracted and recorded.Data were compared and analyzed using SPSS 22.0.Results A total of 24 studies were included,composing of 10 studies of COVID-19,5 studies of MERS and 9 studies of SARS.The included CT exams were 147,40,and 122 respectively.For the early CT features of the 3 pneumonias,the basic lesion pattern with respect to"mixed ground glass opacity(GGO)and consolidation,GGO mainly,or consolidation mainly"was similar among the 3 groups(χ^2=7.966,P>0.05).There were no significant differences on the lesion distribution(χ^2=13.053,P>0.05)and predominate involvement of the subpleural area of bilateral lower lobes(χ^2=4.809,P>0.05)among the 3 groups.The lesions appeared more focal in COVID-19 pneumonia at early phase(χ^2=23.509,P<0.05).The proportions of crazy-paving pattern(χ^2=23.037,P<0.001),organizing pneumonia pattern(P<0.05)and pleural effusions(P<0.001)in COVID-19 pneumonia were significantly lower than the other two.Although rarely shown in the early CT findings of all three viral pneumonias,the fibrotic changes were more frequent in SARS than COVID-19 and MERS(χ^2=6.275,P<0.05).For other imaging signs,only the MERS pneumonia demonstrated tree-in-buds,cavitation,and its incidence rate of interlobular or intralobular septal thickening presented significantly increased as compared to the other two pneumonia(χ^2=22.412,P<0.05).No pneumothorax,pneumomediastinum and lymphadenopathy was present for each group.Conclusions Imaging findings on early stage of these three coronavirus pneumonias showed similar basic lesion patterns,including GGO and consolidation,bilateral distribution,and predominant involvement of the subpleural area and the lower lobes.Early signs of COVID-19 pneumonia showed less severity of inflammation.Early fibrotic changes appeared in SARS only.MERS had more severe inflammatory changes including cavitation and pleural effusion.The differences may indicate the specific pathophysiological processes for each coronavirus pneumonia.
基金the Third People’s Hospital of Shenzhen Scientific Research Project,No.G2021008 and No.G2022008Shenzhen Key Medical Discipline Construction Fund,No.SZXK079Shenzhen Science and Technology Research and Development Fund,No.JCYJ20190809165813331 and No.JCYJ20210324131809027.
文摘BACKGROUND Thrombectomy and anatomical anastomosis(TAA)has long been considered the optimal approach to portal vein thrombosis(PVT)in liver transplantation(LT).However,TAA and the current approach for non-physiological portal reconstructions are associated with a higher rate of complications and mortality in some cases.AIM To describe a new choice for reconstructing the portal vein through a posterior pancreatic tunnel(RPVPPT)to address cases of unresectable PVT.METHODS Between August 2019 and August 2021,245 adult LTs were performed.Forty-five(18.4%)patients were confirmed to have PVT before surgery,among which seven underwent PV reconstruction via the RPVPPT approach.We retrospectively analyzed the surgical procedure and postoperative complications of these seven recipients that underwent PV reconstruction due to PVT.RESULTS During the procedure,PVT was found in all the seven cases with significant adhesion to the vascular wall and could not be dissected.The portal vein proximal to the superior mesenteric vein was damaged in one case when attempting thrombolectomy,resulting in massive bleeding.LT was successfully performed in all patients with a mean duration of 585 min(range 491-756 min)and mean intraoperative blood loss of 800 mL(range 500-3000 mL).Postoperative complications consisted of chylous leakage(n=3),insufficient portal venous flow to the graft(n=1),intra-abdominal hemorrhage(n=1),pulmonary infection(n=1),and perioperative death(n=1).The remaining six patients survived at 12-17 mo follow-up.CONCLUSION The RPVPPT technique might be a safe and effective surgical procedure during LT for complex PVT.However,follow-up studies with large samples are still warranted due to the relatively small number of cases.
基金supported in part by Tokyo Denki University Science Promotion Fund(Q12K-04)
文摘The motion of a lure in water is investigated experimentally and numerically.The lure motion in water of apassing water tank is observed,and the periodic motion is found.From the Fourier analysis,it is found that the frequency with the largest amplitude in the lateral direction depends on the lip width of the lure.To understand the lure dynamics,a numerical simulation of the flow field around the lure is performed.The shape is measured using an X-ray computer tomography and converted into a voxel model.From visualization,it is found that vortex sheds from its lip correspond to the vibration frequency of the lure.
文摘Objective: Evaluation of peripheral arterial disease with 64-detector multi-slice CT angiography (MDCT- A) and comparison of the results with the results of digital subtraction angiography (DSA), a standard reference. Materials and Method: The written informed consent of the patients and ethics committee approval were obtained. The retrospective study group consisted of 28 patients with a diagnosis of peripheral arterial disease. Using 64-MDCT-A, the arterial tree of the lower extremity was evaluated for the presence of steno-occlusive lesions that might have led to luminal stenosis. The diagnostic reliability of 64-MDCT- A was calculated and compared with that of DSA. Findings: In the segment-based analysis, the sensitivity, specificity, and reliability rates of 64-MDCT angiography in determining significant stenoses were 97.7%, 97%, and 97.3%, respectively. The Kappa co-efficiency for compatibility between 64-MDCT-A and DSA methods in grading stenosis was calculated as 0.896
基金the National Natural Science Foundation of China (Key Program),No.11032008the National Natural Science Foundation of China (General Program),No. 10872140+1 种基金10702048the Natural Science Foundation of Shanxi Province,No.2010021004-1
文摘A middle-aged male patient with a right orbital comminuted fracture underwent computer tomography scanning, and a three-dimensional finite element model of the eyes and relevant tissues was established. Optic nerve stress in a hyperbaric oxygen environment was simulated and analyzed by changing the elastic modulus and external pressure of the skull at the damage side. Results showed that stress maximized at the contact site of the optic nerve and the eyeball in the damaged and intact eye orbits. Optic nerve stress at the damaged orbit significantly increased; however, stress in the intact orbit only slightly changed with decreased elastic modulus of the skull while external pressure remained unchanged. Maximum optic nerve stress increased in the damaged and intact side, along with increased external pressure, while elastic modulus remained unchanged. These experimental findings suggested that the optic nerve was compressed under hyperbaric oxygen and optic nerve stress was greater in the damaged orbit than in the intact orbit.
文摘Pancreatic fat accumulation has been described with various terms including pancreatic lipomatosis, pancreatic steatosis, fatty replacement, fatty infiltration, fatty pancreas, lipomatous pseudohypertrophy and nonalcoholic fatty pancreas disease. It has been reported to be associated with type 2 diabetes mellitus, acute pancreatitis, pancreatic cancer and the formation of pancreatic fistula. The real incidence of this condition is still unknown. We report a case of pancreatic steatosis in a non-obese female patient initially diagnosed with a mass in the head of the pancreas. Magnetic resonance imaging(MRI) was carried out to define the characteristics of the pancreatic mass. MRI confirmed the diagnosis of fat pancreas. Enlarged pancreas is not always a cancer, but pancreatic steatosis is characterized by pancreatic enlargement. MRI could give a definite diagnosis of pancreatic steatosis or cancer.
文摘Over the past twenty years, improvements in neuroimaging have greatly improved the ability to diagnose cerebral venous sinus thrombosis, as well as isolated cortical venous thrombosis. Neuroimaging allows for variations to be detected in the cortical vein and venous sinus. Diagnosis of thromboses in the venous system should not depend entirely on angiography of undeveloped veins or venous sinus. Currently, the combination of magnetic resonance imaging and magnetic resonance venography is the gold standard for diagnosing cerebral venous sinus thrombosis, rather than digital subtraction angiography. This article summarizes clinical manifestations, results from computed tomography and magnetic resonance imaging in two cases of isolated cortical venous thrombosis, analyzed relevant literature, and discussed the clinical and imaging characteristics of isolated cortical venous thromboses.
文摘BACKGROUND Peliosis hepatis(PH)is a rare benign lesion of vascular origin with a pathological characteristic of multiple blood-filled cavities in the liver parenchyma.It is commonly misdiagnosed due to its lack of specificity in clinical presentation and laboratory test results.Herein,a case of a patient with PH who was misdiagnosed with hepatic echinococcosis before operation to remove the lesions was analyzed,with an emphasis on the computed tomography and magnetic resonance imaging characteristics of PH.CASE SUMMARY We outline the case of a 40-year-old Chinese female who was admitted with aggravated abdominal pain with fever for 1 wk.Ultrasound examination at the local hospital indicated hepatic echinococcosis.However,discordance between imaging diagnosis,clinical history and laboratory examinations in our hospital.Subsequently,the patient was pathologically confirmed as having PH-like changes,which recurred 1 year after operation removal of the lesion.CONCLUSION Our objective is to highlight the imaging diagnostic value of PH.
文摘Background Safe placement of the screws is a critical aspect of trans-pedicle internal fixation, and little information on in vivo morphology of the cervical vertebrae pedicle measured with imaging methods is available. The aim of this study was to measure the dimensions of cervical vertebrae C3 to C7 and provide screw length, screw diameter and tilt angle for clinical cervical vertebra trans-pedicle internal fixation. Methods Thirty Chinese men and women underwent high-speed spiral computed tomography measurements to obtain data for C3 to C7, and the morphology of the cervical vertebra pedicles was reconstructed. Results Reconstructed computer tomography image data revealed that: (1) pedicle sponge width increased incrementally from C3 to C7, (2) pedicle depth was similar for C3 to C7, (3) pedicle angle decreased incrementally from 47.20~ to 33.76~ for' C3 to C7, and (4) pedicle point to midline distance was similar for C3 to C7. There were no statistical differences in morphological data between the right and the left side. Men had statistically larger values than women for all morphological parameters. Conclusions Reconstructed computed tomography images can provide useful data for clinical cervical vertebra trans-pedicle internal fixation. The individual measurement of cervical vertebra pedicles is recommended for safe placement of trans-vertebra pedicle screws.
文摘Morphological changes within the porous architecture of laboratory scale zero valent iron (ZVI) permeable reactive barriers (PRBs), after exposure to different groundwater conditions, have been quantified experimentally for different ZVI/sand ratios (10%, 50% and 100%, W/W) with the aim of inferring porosity changes in field barriers. Column studies were conducted to simulate interaction with different water chemistries, a synthetic groundwater, acidic drainage and deionised (DI) water as control. Morphological changes, in terms of pore size and distribution, were measured using X-ray computed tomography (CT). CT image analysis revealed significant morphological changes in columns treated with different water chemistries. For example, 100% ZVI (W/W) columns had a higher frequency of small pores (0.6 mm) was observed in ZVI grains reacted with typical groundwater, resulting in a porosity of 27%, compared to 32% when exposed to DI water. In comparison, ZVI grains treated with the acidic drainage had higher porosity (44%) and larger average pore size (2.8 mm). 10% ZVI PRB barrier material had the highest mean porosity (56%) after exposure to any water chemistry whilst 100% ZVI (W/W) columns always had the lowest (34%) with the 50% ZVI (W/W) in between (40%). These results agree with previously published PRB field data and simultaneously conducted geochemical monitoring and mass balance calculation, indicating that both the geochemical and hydraulic environment of the PRB play an important role in determining barrier lifespan. This study suggests that X-ray CT image analysis is a powerful tool for studying the detailed inter pores between ZVI grains within PRBs.