BACKGROUND Whole-body magnetic resonance imaging(wbMRI)allows general assessment of systemic cancers including lymphomas without radiation burden.AIM To evaluate the diagnostic performance of wbMRI in the staging of d...BACKGROUND Whole-body magnetic resonance imaging(wbMRI)allows general assessment of systemic cancers including lymphomas without radiation burden.AIM To evaluate the diagnostic performance of wbMRI in the staging of diffuse large B-cell lymphoma(DLBCL),determine the value of individual MRI sequences,and assess patients’concerns with wbMRI.METHODS In this single-center prospective study,adult patients newly diagnosed with systemic DLBCL underwent wbMRI on a 3T scanner[diffusion weighted images with background suppression(DWIBS),T2,short tau inversion recovery(STIR),contrast-enhanced T1]and fluorodeoxyglucose(18F-FDG)positron emission tomo-graphy/computed tomography(PET/CT)(reference standard).The involvement of 12 nodal regions and extranodal sites was evaluated on wbMRI and PET/CT.The utility of wbMRI sequences was rated on a five-point scale(0=not useful,4=very useful).Patients received a questionnaire regarding wbMRI.RESULTS Of 60 eligible patients,14(23%)were enrolled and completed the study.The sensitivity of wbMRI in the nodal involvement(182 nodal sites)was 0.84,with 0.99 specificity,positive predictive value of 0.96,negative predictive value of 0.97,and 0.97 accuracy.PET/CT and wbMRI were concordant both in extranodal involvement(13 instances)and staging(κ=1.0).The mean scores of the utility of MRI sequences were 3.71±0.73 for DWIBS,2.64±0.84 for T1,2.14±0.77 for STIR,and 1.29±0.73 for T2(P<0.0001).Patients were mostly concerned about the enclosed environment and duration of the MRI examination(27%of patients).CONCLUSION The wbMRI exhibited excellent sensitivity and specificity in staging DLBCL.DWIBS and contrast-enhanced T1 were rated as the most useful sequences.Patients were less willing to undergo wbMRI as a second examination parallel to PET/CT,especially owing to the long duration and the enclosed environment.展开更多
Introduction.Osteogenesis imperfecta(OI),also known as brittle bone disease,is a phenotypically diverse disorder due to deficiencies in the synthesis of type I collagen.OI is a disease characterized by brittle bones a...Introduction.Osteogenesis imperfecta(OI),also known as brittle bone disease,is a phenotypically diverse disorder due to deficiencies in the synthesis of type I collagen.OI is a disease characterized by brittle bones and frequent fractures with minimal trauma leading to skeletal deformities[1].Its incidence is estimated at 1 per 20,000 births.Though rare,it is the most common inherited disorder of connective tissue.Principally,it affects bone,but it also impacts other tissues rich in type I collagen,such as joints,eyes,ears,skin,and teeth.展开更多
AIM: To compare breath-hold cartesian volumetric interpolated breath-hold examination(cVIBE) and freebreathing radial VIBE(rVIBE) and determine whether rVIBE could replace cVIBE in routine liver magnetic resonance ima...AIM: To compare breath-hold cartesian volumetric interpolated breath-hold examination(cVIBE) and freebreathing radial VIBE(rVIBE) and determine whether rVIBE could replace cVIBE in routine liver magnetic resonance imaging(MRI).METHODS: In this prospective study, 15 consecutive patients scheduled for routine MRI of the abdomen underwent pre- and post-contrast breath-hold cVIBE imaging(19 s acquisition time) and free-breathing rVIBE imaging(111 s acquisition time) on a 1.5T Siemens scanner. Three radiologists with 2, 4, and 8 years post-fellowship experience in abdominal imaging evaluated all images. The radiologists were blinded to the sequence types, which were presented in a random order for each patient. For each sequence, the radiologists scored the cVIBE and rVIBE images for liver edge sharpness, hepatic vessel clarity, presence of artifacts, lesion conspicuity, fat saturation, and overall image quality using a five-point scale. RESULTS: Compared to rVIBE, cVIBE yielded significantly(P < 0.001) higher scores for liver edge sharpness(mean score, 3.87 vs 3.37), hepatic-vessel clarity(3.71 vs 3.18), artifacts(3.74 vs 3.06), lesion conspicuity(3.81 vs 3.2), and overall image quality(3.91 vs 3.24). cVIBE and rVIBE did not significantly differ in quality of fat saturation(4.12 vs 4.03, P = 0.17). The inter-observer variability with respect to differences between rVIBE and cVIBE scores was close to zero compared to random error and inter-patient variation. Quality of rVIBE images was rated as acceptable for all parameters. CONCLUSION: rVIBE cannot replace cVIBE in routine liver MRI. At 1.5T, free-breathing rVIBE yields acceptable, although slightly inferior image quality compared to breath-hold cVIBE.展开更多
Five types of superparamagnetic iron oxide （SPIO）,i.e. Ferumoxides （Feridex？ Ⅳ, Berlex Laboratories）,Fe r u c a r b o t ra n （ Re s ov i s t？, B aye r H e a l t h c a re ） ,Ferumoxtran-10 （AMI-227 or Code-72...Five types of superparamagnetic iron oxide （SPIO）,i.e. Ferumoxides （Feridex？ Ⅳ, Berlex Laboratories）,Fe r u c a r b o t ra n （ Re s ov i s t？, B aye r H e a l t h c a re ） ,Ferumoxtran-10 （AMI-227 or Code-7227, Combidex？, AMAG Pharma; Sinerem？, Guerbet）, NC100150（Clariscan？, Nycomed,） and （VSOP C184, Ferropharm）have been designed and clinically tested as magneticresonance contrast agents. However, until nowResovist？ is current available in only a few countries.The other four agents have been stopped for furtherdevelopment or withdrawn from the market. AnotherSPIO agent Ferumoxytol （Feraheme） is approved forthe treatment of iron deficiency in adult chronic kidneydisease patients. Ferumoxytol is comprised of ironoxide particles surrounded by a carbohydrate coat, andit is being explored as a potential imaging approach forevaluating lymph nodes and certain liver tumors.展开更多
AIM: To compare apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) of hepatic fibrosis patients with those of healthy controls and to identify their correlations with serum indices of live...AIM: To compare apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) of hepatic fibrosis patients with those of healthy controls and to identify their correlations with serum indices of liver fibrosis.展开更多
Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identif ication and characterisation of both malignant and benign liver lesions. Imaging techniques available i...Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identif ication and characterisation of both malignant and benign liver lesions. Imaging techniques available include contrast enhanced ultrasound, computed tomography and magnetic resonance imaging. This review discusses the application of several imaging techniques in the diagnosis and staging of both hepatocellular carcinoma and cholangiocarcinoma and outlines certain characteristics of benign liver lesions. The advantages of each imaging technique are highlighted, while underscoring the potential pitfalls and limitations of each imaging modality.展开更多
The main goal of this study was to introduce a novel three-dimensional procedure to objectively quantify both inner and outer condylar remodelling on preoperative multi-slice computed tomography （MSCT） and postopera...The main goal of this study was to introduce a novel three-dimensional procedure to objectively quantify both inner and outer condylar remodelling on preoperative multi-slice computed tomography （MSCT） and postoperative cone-beam computed tomography （CBCT） images. Second, the reliability and accuracy of this condylar volume quantification method was assessed. The mandibles of 20 patients （11 female and 9 male） who underwent bimaxillary surgery were semi-automatically extracted from MSCT/CBCT scans and rendered in 3D. The resulting condyles were spatially matched by using an anatomical landmark-based registration procedure. A standardized sphere was created around each condyle, and the condylar bone volume within this selected region of interest was automatically calculated. To investigate the reproducibility of the method, inter- and intra-observer reliability was calculated for assessments made by two experienced radiologists twice five months apart in a set of ten randomly selected patients. To test the accuracy of the bone segmentation, the inner and outer bone structures of one dry mandible, scanned according to the clinical set-up, were compared with the gold standard, micro-CT. Thirty-eight condyles showed a significant （P〈O.05） mean bone volume decrease of 26.4%_ 11.4% （502.9 mm3＋ 268.1 mm3）. No significant effects of side, sex or age were found. Good to excellent （ICC〉 0.6） intra- and inter-observer reliability was observed for both MSCT and CBCT. Moreover, the bone segmentation accuracy was less than one voxel （0.4 mm） for MSCT （0.3 mm __. 0.2 mm） and CBCT （0.4 mm _ 0.3 mm）, thus indicating the clinical potential of this method for objective follow-up in pathological condylar resorption.展开更多
The anterior cruciate ligament(ACL)is an important structure in maintaining the normal biomechanics of the knee and is the most commonly injured knee ligament.However,the oblique course of the ACL within the intercond...The anterior cruciate ligament(ACL)is an important structure in maintaining the normal biomechanics of the knee and is the most commonly injured knee ligament.However,the oblique course of the ACL within the intercondylar fossa limits the visualization and assessment of the pathology of the ligament.This pictorial essay provides a comprehensive and illustrative review of the anatomy and biomechanics as well as updated information on different modalities of radiological investigation of ACL,particularly magnetic resonance imaging.展开更多
BACKGROUND Diffusion-weighted imaging(DWI)has become a useful tool in the detection,characterization,and evaluation of response to treatment of many cancers,including malignant liver lesions.DWI offers higher image co...BACKGROUND Diffusion-weighted imaging(DWI)has become a useful tool in the detection,characterization,and evaluation of response to treatment of many cancers,including malignant liver lesions.DWI offers higher image contrast between lesions and normal liver tissue than other sequences.DWI images acquired at two or more b-values can be used to derive an apparent diffusion coefficient(ADC).DWI in the body has several technical challenges.This include ghosting artifacts,mis-registration and susceptibility artifacts.New DWI sequences have been developed to overcome some of these challenges.Our goal is to evaluate 3 new DWI sequences for liver imaging.AIM To qualitatively and quantitatively compare 3 DWI sequences for liver imaging:free-breathing(FB),simultaneous multislice(SMS),and prospective acquisition correction(PACE).METHODS Magnetic resonance imaging(MRI)was performed in 20 patients in this prospective study.The MR study included 3 separate DWI sequences:FB-DWI,SMS-DWI,and PACE-DWI.The image quality,mean ADC,standard deviations(SD)of ADC,and ADC histogram were compared.Wilcoxon signed-rank tests were used to compare qualitative image quality.A linear mixed model was used to compare the mean ADC and the SDs of the ADC values.All tests were 2-sided and P values of<0.05 were considered statistically significant.RESULTS There were 56 lesions(50 malignant)evaluated in this study.The mean qualitative image quality score of PACE-DWI was 4.48.This was significantly better than that of SMS-DWI(4.22)and FB-DWI(3.15)(P<0.05).Quantitatively,the mean ADC values from the 3 different sequences did not significantly differ for each liver lesion.FB-DWI had a markedly higher variation in the SD of the ADC values than did SMS-DWI and PACE-DWI.We found statistically significant differences in the SDs of the ADC values for FB-DWI vs PACE-DWI(P<0.0001)and for FB-DWI vs SMS-DWI(P=0.03).The SD of the ADC values was not statistically significant for PACE-DWI and SMS-DWI(P=0.18).The quality of the PACE-DWI ADC histograms were considered better than the SMS-DWI and FB-DWI.CONCLUSION Compared to FB-DWI,both PACE-DWI and SMS-DWI provide better image quality and decreased quantitative variability in the measurement of ADC values of liver lesions.展开更多
Since it has been recognized that sarcoidosis(SA) is not an exclusive disorder of the lungs but can also affect other organs such as the liver and spleen, efforts have been made to define specific imaging criteria for...Since it has been recognized that sarcoidosis(SA) is not an exclusive disorder of the lungs but can also affect other organs such as the liver and spleen, efforts have been made to define specific imaging criteria for the diagnosis of the single organ involvement, and the concept has been reinforced that the exclusion of alternative causes is important to achieve the correct diagnosis. Ultrasound(US)is a useful tool to evaluate patients with suspected abdominal SA, such as of the liver, spleen, kidney, pancreas and other organs, showing findings such as organomegaly, focal lesions and lymphadenopathy. While the diagnosis of abdominal SA is more predictable in the case of involvement of other organs(e.g.,lungs), the problem is more complex in the case of isolated abdominal SA. The recent use of contrast-enhanced ultrasound and endoscopic ultrasound elastography has provided additional information about the enhancement patterns and tissue rigidity in abdominal SA. Here we critically review the role of US in abdominal SA, reporting typical findings and limitations of current evidence and by discussing future perspectives of study.展开更多
Different causative factors acting on the pancreas can result in diseases such as pancreatitis, diabetes and pancreatic tumors. The high incidence and mortality of pancreatic diseases have placed diagnostic imaging in...Different causative factors acting on the pancreas can result in diseases such as pancreatitis, diabetes and pancreatic tumors. The high incidence and mortality of pancreatic diseases have placed diagnostic imaging in a crucial position in daily clinical practice. In this minireview article different pancreatic imaging techniques are discussed, from the standard clinical imaging modalities and state of the art clinical magnetic resonance imaging techniques to current situations in pre-clinical pancreatic imaging studies. In particular, the challenges of pre-clinical rodent pancreatic imaging are addressed, with both the image acquisition techniques and the post-processing methods for rodent pancreatic imaging elaborated.展开更多
Objective:The aim was to evaluate the role of whole body diffusion weighted imaging(WB-DWI) of magnetic resonance in the diagnosis and efficacy evaluation of malignant lymphoma.Methods:The clinical manifestation of wh...Objective:The aim was to evaluate the role of whole body diffusion weighted imaging(WB-DWI) of magnetic resonance in the diagnosis and efficacy evaluation of malignant lymphoma.Methods:The clinical manifestation of whole body diffusion weighted imaging of 47 patients with malignant lymphoma being pathologically proved were carried on by retrospective analysis and to compare with 10 healthy volunteers.There were 8 cases of Hodgkin's lymphoma(HD) patients,of which WB-DWI examination of 5 cases were carried out before and after treatment and 3 cases were done after treatment.There were 39 cases of non-Hodgkin's lymphoma(NHL) patients,of which WB-DWI examination in 19 cases were acted before treatment,11 cases were done before and after treatment and 9 cases done after treatment.In apparent diffusion coefficient(ADC) diagram the ADC values of lymph nodes in patients with malignant lymphoma and healthy volunteers were measured respectively,among 16 patients the ADC values of parts of lymph node being consistent with the initial inspection were determined again and compared the values before and after,and compared with healthy volunteers.Results:Whole body magnetic resonance diffusion weighted imaging(MR-DWI) showed more sensitive to lymphoma,and 372 lymph nodes greater than 1 cm were detected with MR-DWI.Before treatment,mean ADC value of 35 patients with malignant lymphoma was(0.86 ± 0.21) × 10-3 mm2/s,of which an average ADC values of 28 cases after treatment was(1.22 ± 0.31) × 10-3 mm2/s,before and after treatment difference of the average ADC values of patients was statistically significant(P < 0.05);the average ADC value of cervical lymph nodes of 10 healthy volunteers(1.29 ± 0.12) × 10-3 mm2/s and of 30 patients with malignant lymphoma before treatment was statistically significant(P < 0.05),and to compare with 28 patients after treatment difference of the ADC values was not statistically significant(P > 0.05).Conclusion:WB-DWI and ADC values being measured in the clinical diagnosis of malignant lymphoma,staging and evaluation of efficacy of monitoring is a fast and effective technology,with some clinical value.展开更多
Esophageal cancer,also referred to as esophagus cancer,is a prevalent disease in the cardiothoracic field and is a leading cause of cancer-related mortality in China.Accurately determining the status of lymph nodes is...Esophageal cancer,also referred to as esophagus cancer,is a prevalent disease in the cardiothoracic field and is a leading cause of cancer-related mortality in China.Accurately determining the status of lymph nodes is crucial for developing treatment plans,defining the scope of intraoperative lymph node dissection,and ascertaining the prognosis of patients with esophageal cancer.Recent advances in diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging(MRI)have improved the effectiveness of MRI for assessing lymph node involvement,making it a beneficial tool for guiding personalized treatment plans for patients with esophageal cancer in a clinical setting.Radiomics is a recently developed imaging technique that transforms radiological image data from regions of interest into high-dimensional feature data that can be analyzed.The features,such as shape,texture,and waveform,are associated with the cancer phenotype and tumor microenvironment.When these features correlate with the clinical disease outcomes,they form the basis for specific and reliable clinical evidence.This study aimed to review the potential clinical applications of MRIbased radiomics in studying the lymph nodes affected by esophageal cancer.The combination of MRI and radiomics is a powerful tool for diagnosing and treating esophageal cancer,enabling a more personalized and effectual approach.展开更多
Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severit...Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severity of coronary artery disease. However, the degree of coronary lumen stenosis is not often related to compromising myocardial blood flow, as most of the cardiac events that are caused by atherosclerotic plaques are the result of vulnerable plaques which are prone to rupture. Thus, identification of vulnerable plaques in coronary arteries has become increas-ingly important to assist identify patients with high cardiovascular risks. Molecular imaging with use of positron emission tomography （PET） and single photon emission computed tomography （SPECT） has fulfilled this goal by providing functional information about plaque activity which enables accurate assessment of plaque stability. This review article provides an overview of diagnostic applications of molecular imaging tech-niques in the detection of plaques in coronary arteries with PET and SPECT. New radiopharmaceuticals used in the molecular imaging of coro-nary plaques and diagnostic applications of integrated PET/CT and PET/MRI in coronary plaques are also discussed.展开更多
Objectives The coronary artery calcium (CAC) score has been shown to predict future cardiac events. However the extent to which the added value of a CAC score to the diagnostic performance of myocardial perfusion imag...Objectives The coronary artery calcium (CAC) score has been shown to predict future cardiac events. However the extent to which the added value of a CAC score to the diagnostic performance of myocardial perfusion imaging (MPI) by single photon emission computed tomography (SPECT) is unclear. The purpose of this study is to investigate the correlation between CAC score and SPECT in patients with suspected coronary artery disease. Methods A retrospective review of the CAC scores by use of the Agatston calcium scoring method and cardiac SPECT diagnostic reports was conducted in 48 patients, who underwent both coronary computed tomography (CT) and SPECT examinations due to suspected coronary artery disease. A Pearson correlation test was used to determine the relation between CAC scores and MPI-SPECT assessments with regard to the evaluation of the extent of disease. Results Forty-seven percent of the patients had CAC scores more than 100, while 42% of these patients demonstrated abnormal, or probably abnormal, MPI-SPECT. Of the 23% of patients with a zero CAC score, only 7% had normal MPI-SPECT findings. No significant correlation was found between the CAC scores and MPISPECT assessments (r value ranged from 0.012 to 0.080), regardless of the degree of coronary calcification. Conclusions There is a lack of correlation between the CAC scores and the MPI-SPECT findings in the assessment of the extent of coronary artery disease. CAC scores and MPI-SPECT should be considered complementary approaches in the evaluation of patientswith suspected coronary artery disease.展开更多
Objective:To explore the clinical methods and clinical effects of applying magnetic resonance imaging(MRI)and 64・slice spiral computed tomography(CT)in the diagnosis of patients with ischemic heart disease.Methods:100...Objective:To explore the clinical methods and clinical effects of applying magnetic resonance imaging(MRI)and 64・slice spiral computed tomography(CT)in the diagnosis of patients with ischemic heart disease.Methods:100 patients with ischemic heart disease were selected as the research objects.Selecting the patients from May 2020 to May 2021 as a sample,the patients were divided into two groups,and different diagnostic methods were used to compare the clinical diagnosis effects.Results:In terms of the diagnostic accuracy of the two groups of patients,the maximum value was 92.00%(experimental group)and the minimum value was 80.00%(control group).There was a big difference in data between the two groups,P<0.05,which was statistically significant.The patient9s(experimental group)diagnosis accuracy rate is highe Conclusion:In the process of research work for patients with ischemic heart disease,it is particularly important to diagnose the patients.The combined application of and 64-slice spiral CT can improve the clinical diagnosis efficiency and achieve significant results.展开更多
AIM: To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.METHODS: Cholesterol, mixed and pigment stones fr...AIM: To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.METHODS: Cholesterol, mixed and pigment stones from cholecystectomy patients were incubated with hypericin or solvent. After 72 h, the stones were analysed for fluorescence(365 nm) and treated with 2-propanol/dimethyl sulfoxide for high performance liquid chromatography(HPLC) analysis. Rats with virtual gallbladder containing human cholesterol, mixed or pigment gallstones(VGHG) received 5 mg/kg hypericin or solvent and VGHG rats with cholesterol stones were given different hypericin doses(5-15 mg/kg). Twelve hours later, the stones were analysed at 365 nm. Biliary excretion and metabolites of hypericin were assessed in common bile duct(CBD) cannulated rats for 9 h using fluorospectrometry, HPLC and matrixassisted laser desorption/ionization-time-of-flight mass spectrometry(MALDI-TOF MS).RESULTS: Homogeneous high fluorescence was seen on cholesterol stones either pre-incubated with hypericin or extracted from VGHG rats receiving hypericin. Mixed stones showed a dotted fluorescent pattern, whereas pigment and solvent-treated ones lacked fluorescence. HPLC showed 7.68, 6.65 and 0.08 × 10^(-3) M of cholesterol in extracts from cholesterol, mixed, and pigment gallstones, respectively. Hypericin accounted for 2.0, 0.5 and 0.2 × 10-6 M in that order. On cholesterol stones from VGHG rats receiving different hypericin doses, a positive correlation was observed between dose and fluorescence. In the bile from CBD-cannulated rats, fluorescence represented 20% of the injected dose with two peaks in 9 h. HPLC analysis revealed that hypericin conjugates reached 60% of the peak area. By MALDI-TOF MS, hypericinglucuronide was detected. CONCLUSION: This study proves the potential use of hypericin for differential fluorescent detection of human gallstones regarding their chemical composition.展开更多
BACKGROUND Desmoid fibroma is a rare soft tissue tumor originating from the aponeurosis,fascia,and muscle,and it is also known as aponeurotic fibroma,invasive fibroma,or ligamentous fibroma.AIM To investigate the clin...BACKGROUND Desmoid fibroma is a rare soft tissue tumor originating from the aponeurosis,fascia,and muscle,and it is also known as aponeurotic fibroma,invasive fibroma,or ligamentous fibroma.AIM To investigate the clinical and imaging features of desmoid tumors of the extremities.METHODS Thirteen patients with desmoid fibroma of the extremities admitted to our hospital from October 2016 to March 2021 were included.All patients underwent computed tomography(CT),magnetic resonance imaging(MRI),and pathological examination of the lesion.Data on the diameter and distribution of the lesion,the relationship between the lesion morphology and surrounding structures,MRI and CT findings,and pathological features were statistically analyzed.RESULTS The lesion diameter ranged from 1.7 to 8.9 cm,with an average of 5.35±2.39 cm.All lesions were located in the deep muscular space,with the left and right forearm each accounting for 23.08%of cases.Among the 13 patients with desmoid fibroma of the extremities,the lesions were"patchy"in 1 case,irregular in 10,and quasi-round in 2.The boundary between the lesion and surrounding soft tissue was blurred in 10 cases,and the focus infiltrated along the tissue space and invaded the adjacent structures.Furthermore,the edge of the lesion showed"beard-like"infiltration in 2 cases;bone resorption and damage were found in 8,and bending of the bone was present in 2;the boundary of the focus was clear in 1.According to the MRI examination,the lesions were larger than 5 cm(61.54%),round or fusiform in shape(84.62%),had an unclear boundary(76.92%),showed uniform signal(69.23%),inhomogeneous enhancement(84.62%),and"root"or"claw"infiltration(69.23%).Neurovascular tract invasion was present in 30.77%of cases.CT examination showed that the desmoid tumors had slightly a lower density(69.23%),higher enhancement(61.54%),and unclear boundary(84.62%);a CT value<50 Hu was present in 53.85%of lesions,and the enhancement was uneven in 53.85%of cases.Microscopically,fibroblasts and myofibroblasts were arranged in strands and bundles,without obvious atypia but with occasional karyotyping;cells were surrounded by collagen tissue.There were disparities in the proportion of collagen tissue in different regions,with abundant collagen tissue and few tumor cells in some areas,similar to the structure of aponeuroses or ligaments,and tumor cells invading the surrounding tissues.CONCLUSION Desmoid tumors of the extremities have certain imaging features on CT and MRI.The two imaging techniques can be combined to improve the diagnostic accuracy,achieve a comprehensive diagnosis of the disease in the clinical practice,and reduce the risk of missed diagnosis or misdiagnosis.In addition,their use can ensure timely diagnosis and treatment.展开更多
Tissue-classification-based attenuation correction strategies have been previously proposed to correct for bone attenuation in PET/MR imaging and simulated using computed tomography. However, the complication of voxel...Tissue-classification-based attenuation correction strategies have been previously proposed to correct for bone attenuation in PET/MR imaging and simulated using computed tomography. However, the complication of voxel averaging uniquely associated with bone has not been considered explicitly in the past. This study investigated the effect of voxel averaging between bone and soft tissue in attenuation images and determined how accurately bone must be detected in MR images in order to perform acceptable attenuation correction of PET data by using CT-simulated attenuation correction. We found out that treating bone as soft tissue caused a mean quantification difference of -9.9% ± 5.5% in all 119 bone lesions. There were no significant differences between lesions in the pelvis and the vertebrae. The nominal difference in lesions in the ribs was significantly lower, likely due to the spatial misregistration between the emission and attenuation images. Interestingly, a non-monotonic relationship between the bone imaging ability and the absolute PET quantification accuracy was observed, with the minimal quantification difference achieved at a BVF around 40% for skull lesions (2.6% ± 2.1%), and 30% for non-skull lesions (1.4% ± 1.1%) and all lesions (1.5% ± 1.3%). This study established that a bone classification sensitivity of approximately 30% BVF is required in order for MR-based attenuation correction methods to achieve optimal quantification in whole-body PET/MR studies. For this purpose, higher bone imaging ability of MR may not be necessary.展开更多
Objective: To compare and analyze the image quality and radiation dose of three scanning modes of dual-source CT coronary artery retrospectively, and to discuss the application value of TurboFlash coarse pitch scannin...Objective: To compare and analyze the image quality and radiation dose of three scanning modes of dual-source CT coronary artery retrospectively, and to discuss the application value of TurboFlash coarse pitch scanning mode. Methods: The imaging data of 100 patients who underwent CT coronary angiography (CCTA) using Siemens force CT retrospective gated triggering spiral scan (RES-SPIRAL), adaptive prospective gated triggering sequence scan (SEQ) and prospective coarse pitch scan (TurboFlash) retrospectively was collected. The image quality was evaluated by objective and subjective methods. The effective radiation dose of patients was compared and analyzed, and the indications of the three scanning modes were analyzed. The application value of dual-source CT TurboFlash coarse pitch scanning in coronary artery imaging was evaluated. Results: The results showed that the left main coronary artery, the right coronary artery and their tertiary branches could be clearly displayed in the three groups of images: the left anterior descending branch, the left circumflex branch, and their three-level branches. There was no statistical difference in subjective image quality among the three groups of pictures (P > 0.05). There was no statistical difference in objective evaluation indexes, such as CT value, SNR, CNR and Noise among the three groups (P > 0.05). The patient radiation dose results showed that the effective radiation dose ED of RES-SPIRA scan was (9.22 ± 1.33) mSv. The dose of SEQ was (2.88 ± 2.47) mSv, and the dose of TurboFlash was (0.51 ± 0.16) mSv. There was significant difference in comparison of the three groups (P 0.05). RES-spiral scanning had the highest radiation dose and TurboFlash coarse pitch scanning (TurboFlash) had the lowest radiation dose. Conclusion: TurboFlash coarse pitch scanning is low in dosage, fast in speed and wide in adaptability. It is especially suitable for the elderly, children, coma and other patients who cannot cooperate with breath-holding examination, as well as for the screening and examination of coronary artery diseases in asymptomatic population. Undoubtedly, it is a worthy method of heart coronary artery examination.展开更多
基金Supported by the Czech Ministry of Health,General University Hospital in Prague,No.VFN00064165。
文摘BACKGROUND Whole-body magnetic resonance imaging(wbMRI)allows general assessment of systemic cancers including lymphomas without radiation burden.AIM To evaluate the diagnostic performance of wbMRI in the staging of diffuse large B-cell lymphoma(DLBCL),determine the value of individual MRI sequences,and assess patients’concerns with wbMRI.METHODS In this single-center prospective study,adult patients newly diagnosed with systemic DLBCL underwent wbMRI on a 3T scanner[diffusion weighted images with background suppression(DWIBS),T2,short tau inversion recovery(STIR),contrast-enhanced T1]and fluorodeoxyglucose(18F-FDG)positron emission tomo-graphy/computed tomography(PET/CT)(reference standard).The involvement of 12 nodal regions and extranodal sites was evaluated on wbMRI and PET/CT.The utility of wbMRI sequences was rated on a five-point scale(0=not useful,4=very useful).Patients received a questionnaire regarding wbMRI.RESULTS Of 60 eligible patients,14(23%)were enrolled and completed the study.The sensitivity of wbMRI in the nodal involvement(182 nodal sites)was 0.84,with 0.99 specificity,positive predictive value of 0.96,negative predictive value of 0.97,and 0.97 accuracy.PET/CT and wbMRI were concordant both in extranodal involvement(13 instances)and staging(κ=1.0).The mean scores of the utility of MRI sequences were 3.71±0.73 for DWIBS,2.64±0.84 for T1,2.14±0.77 for STIR,and 1.29±0.73 for T2(P<0.0001).Patients were mostly concerned about the enclosed environment and duration of the MRI examination(27%of patients).CONCLUSION The wbMRI exhibited excellent sensitivity and specificity in staging DLBCL.DWIBS and contrast-enhanced T1 were rated as the most useful sequences.Patients were less willing to undergo wbMRI as a second examination parallel to PET/CT,especially owing to the long duration and the enclosed environment.
文摘Introduction.Osteogenesis imperfecta(OI),also known as brittle bone disease,is a phenotypically diverse disorder due to deficiencies in the synthesis of type I collagen.OI is a disease characterized by brittle bones and frequent fractures with minimal trauma leading to skeletal deformities[1].Its incidence is estimated at 1 per 20,000 births.Though rare,it is the most common inherited disorder of connective tissue.Principally,it affects bone,but it also impacts other tissues rich in type I collagen,such as joints,eyes,ears,skin,and teeth.
文摘AIM: To compare breath-hold cartesian volumetric interpolated breath-hold examination(cVIBE) and freebreathing radial VIBE(rVIBE) and determine whether rVIBE could replace cVIBE in routine liver magnetic resonance imaging(MRI).METHODS: In this prospective study, 15 consecutive patients scheduled for routine MRI of the abdomen underwent pre- and post-contrast breath-hold cVIBE imaging(19 s acquisition time) and free-breathing rVIBE imaging(111 s acquisition time) on a 1.5T Siemens scanner. Three radiologists with 2, 4, and 8 years post-fellowship experience in abdominal imaging evaluated all images. The radiologists were blinded to the sequence types, which were presented in a random order for each patient. For each sequence, the radiologists scored the cVIBE and rVIBE images for liver edge sharpness, hepatic vessel clarity, presence of artifacts, lesion conspicuity, fat saturation, and overall image quality using a five-point scale. RESULTS: Compared to rVIBE, cVIBE yielded significantly(P < 0.001) higher scores for liver edge sharpness(mean score, 3.87 vs 3.37), hepatic-vessel clarity(3.71 vs 3.18), artifacts(3.74 vs 3.06), lesion conspicuity(3.81 vs 3.2), and overall image quality(3.91 vs 3.24). cVIBE and rVIBE did not significantly differ in quality of fat saturation(4.12 vs 4.03, P = 0.17). The inter-observer variability with respect to differences between rVIBE and cVIBE scores was close to zero compared to random error and inter-patient variation. Quality of rVIBE images was rated as acceptable for all parameters. CONCLUSION: rVIBE cannot replace cVIBE in routine liver MRI. At 1.5T, free-breathing rVIBE yields acceptable, although slightly inferior image quality compared to breath-hold cVIBE.
文摘Five types of superparamagnetic iron oxide （SPIO）,i.e. Ferumoxides （Feridex？ Ⅳ, Berlex Laboratories）,Fe r u c a r b o t ra n （ Re s ov i s t？, B aye r H e a l t h c a re ） ,Ferumoxtran-10 （AMI-227 or Code-7227, Combidex？, AMAG Pharma; Sinerem？, Guerbet）, NC100150（Clariscan？, Nycomed,） and （VSOP C184, Ferropharm）have been designed and clinically tested as magneticresonance contrast agents. However, until nowResovist？ is current available in only a few countries.The other four agents have been stopped for furtherdevelopment or withdrawn from the market. AnotherSPIO agent Ferumoxytol （Feraheme） is approved forthe treatment of iron deficiency in adult chronic kidneydisease patients. Ferumoxytol is comprised of ironoxide particles surrounded by a carbohydrate coat, andit is being explored as a potential imaging approach forevaluating lymph nodes and certain liver tumors.
文摘AIM: To compare apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) of hepatic fibrosis patients with those of healthy controls and to identify their correlations with serum indices of liver fibrosis.
基金Supported by SAK is supported by a grant from the Higher Education Funding Council for England (HEFCE)SDTR is funded by grants from the British Medical Research Council (MRC), London, UK+3 种基金the British Engineering, Physics and Science Research Council (EPSRC), Swindon, UKthe Alan Morement Memorial Fund AMMF, Essex, UKBroad Foundation, Los Angeles, USAPfizer Global Research and Development Inc, Sandwich, UK and GlaxoSmithKline, Ware, UK
文摘Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identif ication and characterisation of both malignant and benign liver lesions. Imaging techniques available include contrast enhanced ultrasound, computed tomography and magnetic resonance imaging. This review discusses the application of several imaging techniques in the diagnosis and staging of both hepatocellular carcinoma and cholangiocarcinoma and outlines certain characteristics of benign liver lesions. The advantages of each imaging technique are highlighted, while underscoring the potential pitfalls and limitations of each imaging modality.
基金the Coordination for the Improvement of Higher Education Personnel(CAPES)programmeScience without borders from Brazilian governmentthe Research Foundation Flanders(FWO)from Flemish government for the fellowship support
文摘The main goal of this study was to introduce a novel three-dimensional procedure to objectively quantify both inner and outer condylar remodelling on preoperative multi-slice computed tomography （MSCT） and postoperative cone-beam computed tomography （CBCT） images. Second, the reliability and accuracy of this condylar volume quantification method was assessed. The mandibles of 20 patients （11 female and 9 male） who underwent bimaxillary surgery were semi-automatically extracted from MSCT/CBCT scans and rendered in 3D. The resulting condyles were spatially matched by using an anatomical landmark-based registration procedure. A standardized sphere was created around each condyle, and the condylar bone volume within this selected region of interest was automatically calculated. To investigate the reproducibility of the method, inter- and intra-observer reliability was calculated for assessments made by two experienced radiologists twice five months apart in a set of ten randomly selected patients. To test the accuracy of the bone segmentation, the inner and outer bone structures of one dry mandible, scanned according to the clinical set-up, were compared with the gold standard, micro-CT. Thirty-eight condyles showed a significant （P〈O.05） mean bone volume decrease of 26.4%_ 11.4% （502.9 mm3＋ 268.1 mm3）. No significant effects of side, sex or age were found. Good to excellent （ICC〉 0.6） intra- and inter-observer reliability was observed for both MSCT and CBCT. Moreover, the bone segmentation accuracy was less than one voxel （0.4 mm） for MSCT （0.3 mm __. 0.2 mm） and CBCT （0.4 mm _ 0.3 mm）, thus indicating the clinical potential of this method for objective follow-up in pathological condylar resorption.
文摘The anterior cruciate ligament(ACL)is an important structure in maintaining the normal biomechanics of the knee and is the most commonly injured knee ligament.However,the oblique course of the ACL within the intercondylar fossa limits the visualization and assessment of the pathology of the ligament.This pictorial essay provides a comprehensive and illustrative review of the anatomy and biomechanics as well as updated information on different modalities of radiological investigation of ACL,particularly magnetic resonance imaging.
文摘BACKGROUND Diffusion-weighted imaging(DWI)has become a useful tool in the detection,characterization,and evaluation of response to treatment of many cancers,including malignant liver lesions.DWI offers higher image contrast between lesions and normal liver tissue than other sequences.DWI images acquired at two or more b-values can be used to derive an apparent diffusion coefficient(ADC).DWI in the body has several technical challenges.This include ghosting artifacts,mis-registration and susceptibility artifacts.New DWI sequences have been developed to overcome some of these challenges.Our goal is to evaluate 3 new DWI sequences for liver imaging.AIM To qualitatively and quantitatively compare 3 DWI sequences for liver imaging:free-breathing(FB),simultaneous multislice(SMS),and prospective acquisition correction(PACE).METHODS Magnetic resonance imaging(MRI)was performed in 20 patients in this prospective study.The MR study included 3 separate DWI sequences:FB-DWI,SMS-DWI,and PACE-DWI.The image quality,mean ADC,standard deviations(SD)of ADC,and ADC histogram were compared.Wilcoxon signed-rank tests were used to compare qualitative image quality.A linear mixed model was used to compare the mean ADC and the SDs of the ADC values.All tests were 2-sided and P values of<0.05 were considered statistically significant.RESULTS There were 56 lesions(50 malignant)evaluated in this study.The mean qualitative image quality score of PACE-DWI was 4.48.This was significantly better than that of SMS-DWI(4.22)and FB-DWI(3.15)(P<0.05).Quantitatively,the mean ADC values from the 3 different sequences did not significantly differ for each liver lesion.FB-DWI had a markedly higher variation in the SD of the ADC values than did SMS-DWI and PACE-DWI.We found statistically significant differences in the SDs of the ADC values for FB-DWI vs PACE-DWI(P<0.0001)and for FB-DWI vs SMS-DWI(P=0.03).The SD of the ADC values was not statistically significant for PACE-DWI and SMS-DWI(P=0.18).The quality of the PACE-DWI ADC histograms were considered better than the SMS-DWI and FB-DWI.CONCLUSION Compared to FB-DWI,both PACE-DWI and SMS-DWI provide better image quality and decreased quantitative variability in the measurement of ADC values of liver lesions.
文摘Since it has been recognized that sarcoidosis(SA) is not an exclusive disorder of the lungs but can also affect other organs such as the liver and spleen, efforts have been made to define specific imaging criteria for the diagnosis of the single organ involvement, and the concept has been reinforced that the exclusion of alternative causes is important to achieve the correct diagnosis. Ultrasound(US)is a useful tool to evaluate patients with suspected abdominal SA, such as of the liver, spleen, kidney, pancreas and other organs, showing findings such as organomegaly, focal lesions and lymphadenopathy. While the diagnosis of abdominal SA is more predictable in the case of involvement of other organs(e.g.,lungs), the problem is more complex in the case of isolated abdominal SA. The recent use of contrast-enhanced ultrasound and endoscopic ultrasound elastography has provided additional information about the enhancement patterns and tissue rigidity in abdominal SA. Here we critically review the role of US in abdominal SA, reporting typical findings and limitations of current evidence and by discussing future perspectives of study.
文摘Different causative factors acting on the pancreas can result in diseases such as pancreatitis, diabetes and pancreatic tumors. The high incidence and mortality of pancreatic diseases have placed diagnostic imaging in a crucial position in daily clinical practice. In this minireview article different pancreatic imaging techniques are discussed, from the standard clinical imaging modalities and state of the art clinical magnetic resonance imaging techniques to current situations in pre-clinical pancreatic imaging studies. In particular, the challenges of pre-clinical rodent pancreatic imaging are addressed, with both the image acquisition techniques and the post-processing methods for rodent pancreatic imaging elaborated.
文摘Objective:The aim was to evaluate the role of whole body diffusion weighted imaging(WB-DWI) of magnetic resonance in the diagnosis and efficacy evaluation of malignant lymphoma.Methods:The clinical manifestation of whole body diffusion weighted imaging of 47 patients with malignant lymphoma being pathologically proved were carried on by retrospective analysis and to compare with 10 healthy volunteers.There were 8 cases of Hodgkin's lymphoma(HD) patients,of which WB-DWI examination of 5 cases were carried out before and after treatment and 3 cases were done after treatment.There were 39 cases of non-Hodgkin's lymphoma(NHL) patients,of which WB-DWI examination in 19 cases were acted before treatment,11 cases were done before and after treatment and 9 cases done after treatment.In apparent diffusion coefficient(ADC) diagram the ADC values of lymph nodes in patients with malignant lymphoma and healthy volunteers were measured respectively,among 16 patients the ADC values of parts of lymph node being consistent with the initial inspection were determined again and compared the values before and after,and compared with healthy volunteers.Results:Whole body magnetic resonance diffusion weighted imaging(MR-DWI) showed more sensitive to lymphoma,and 372 lymph nodes greater than 1 cm were detected with MR-DWI.Before treatment,mean ADC value of 35 patients with malignant lymphoma was(0.86 ± 0.21) × 10-3 mm2/s,of which an average ADC values of 28 cases after treatment was(1.22 ± 0.31) × 10-3 mm2/s,before and after treatment difference of the average ADC values of patients was statistically significant(P < 0.05);the average ADC value of cervical lymph nodes of 10 healthy volunteers(1.29 ± 0.12) × 10-3 mm2/s and of 30 patients with malignant lymphoma before treatment was statistically significant(P < 0.05),and to compare with 28 patients after treatment difference of the ADC values was not statistically significant(P > 0.05).Conclusion:WB-DWI and ADC values being measured in the clinical diagnosis of malignant lymphoma,staging and evaluation of efficacy of monitoring is a fast and effective technology,with some clinical value.
文摘Esophageal cancer,also referred to as esophagus cancer,is a prevalent disease in the cardiothoracic field and is a leading cause of cancer-related mortality in China.Accurately determining the status of lymph nodes is crucial for developing treatment plans,defining the scope of intraoperative lymph node dissection,and ascertaining the prognosis of patients with esophageal cancer.Recent advances in diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging(MRI)have improved the effectiveness of MRI for assessing lymph node involvement,making it a beneficial tool for guiding personalized treatment plans for patients with esophageal cancer in a clinical setting.Radiomics is a recently developed imaging technique that transforms radiological image data from regions of interest into high-dimensional feature data that can be analyzed.The features,such as shape,texture,and waveform,are associated with the cancer phenotype and tumor microenvironment.When these features correlate with the clinical disease outcomes,they form the basis for specific and reliable clinical evidence.This study aimed to review the potential clinical applications of MRIbased radiomics in studying the lymph nodes affected by esophageal cancer.The combination of MRI and radiomics is a powerful tool for diagnosing and treating esophageal cancer,enabling a more personalized and effectual approach.
文摘Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severity of coronary artery disease. However, the degree of coronary lumen stenosis is not often related to compromising myocardial blood flow, as most of the cardiac events that are caused by atherosclerotic plaques are the result of vulnerable plaques which are prone to rupture. Thus, identification of vulnerable plaques in coronary arteries has become increas-ingly important to assist identify patients with high cardiovascular risks. Molecular imaging with use of positron emission tomography （PET） and single photon emission computed tomography （SPECT） has fulfilled this goal by providing functional information about plaque activity which enables accurate assessment of plaque stability. This review article provides an overview of diagnostic applications of molecular imaging tech-niques in the detection of plaques in coronary arteries with PET and SPECT. New radiopharmaceuticals used in the molecular imaging of coro-nary plaques and diagnostic applications of integrated PET/CT and PET/MRI in coronary plaques are also discussed.
文摘Objectives The coronary artery calcium (CAC) score has been shown to predict future cardiac events. However the extent to which the added value of a CAC score to the diagnostic performance of myocardial perfusion imaging (MPI) by single photon emission computed tomography (SPECT) is unclear. The purpose of this study is to investigate the correlation between CAC score and SPECT in patients with suspected coronary artery disease. Methods A retrospective review of the CAC scores by use of the Agatston calcium scoring method and cardiac SPECT diagnostic reports was conducted in 48 patients, who underwent both coronary computed tomography (CT) and SPECT examinations due to suspected coronary artery disease. A Pearson correlation test was used to determine the relation between CAC scores and MPI-SPECT assessments with regard to the evaluation of the extent of disease. Results Forty-seven percent of the patients had CAC scores more than 100, while 42% of these patients demonstrated abnormal, or probably abnormal, MPI-SPECT. Of the 23% of patients with a zero CAC score, only 7% had normal MPI-SPECT findings. No significant correlation was found between the CAC scores and MPISPECT assessments (r value ranged from 0.012 to 0.080), regardless of the degree of coronary calcification. Conclusions There is a lack of correlation between the CAC scores and the MPI-SPECT findings in the assessment of the extent of coronary artery disease. CAC scores and MPI-SPECT should be considered complementary approaches in the evaluation of patientswith suspected coronary artery disease.
文摘Objective:To explore the clinical methods and clinical effects of applying magnetic resonance imaging(MRI)and 64・slice spiral computed tomography(CT)in the diagnosis of patients with ischemic heart disease.Methods:100 patients with ischemic heart disease were selected as the research objects.Selecting the patients from May 2020 to May 2021 as a sample,the patients were divided into two groups,and different diagnostic methods were used to compare the clinical diagnosis effects.Results:In terms of the diagnostic accuracy of the two groups of patients,the maximum value was 92.00%(experimental group)and the minimum value was 80.00%(control group).There was a big difference in data between the two groups,P<0.05,which was statistically significant.The patient9s(experimental group)diagnosis accuracy rate is highe Conclusion:In the process of research work for patients with ischemic heart disease,it is particularly important to diagnose the patients.The combined application of and 64-slice spiral CT can improve the clinical diagnosis efficiency and achieve significant results.
基金Supported by Research Foundation-Flanders(FWO)the KU Leuven Molecular Small Animal Imaging Center Mo SAIC,No.KUL EF/05/08+4 种基金the center of excellence in vivo molecular imaging research(IMIR)KU Leuven projects,No.IOFHB/08/009 and No.IOF-HB/12/018the European Union,AsiaLink Cf P 2006-Europe Aid/123738/C/ACT/Multi-Proposal,No128-498/111National Natural Science Foundation of China,No.81071828Jiangsu Province Natural Science Foundation,No.BK2010594
文摘AIM: To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.METHODS: Cholesterol, mixed and pigment stones from cholecystectomy patients were incubated with hypericin or solvent. After 72 h, the stones were analysed for fluorescence(365 nm) and treated with 2-propanol/dimethyl sulfoxide for high performance liquid chromatography(HPLC) analysis. Rats with virtual gallbladder containing human cholesterol, mixed or pigment gallstones(VGHG) received 5 mg/kg hypericin or solvent and VGHG rats with cholesterol stones were given different hypericin doses(5-15 mg/kg). Twelve hours later, the stones were analysed at 365 nm. Biliary excretion and metabolites of hypericin were assessed in common bile duct(CBD) cannulated rats for 9 h using fluorospectrometry, HPLC and matrixassisted laser desorption/ionization-time-of-flight mass spectrometry(MALDI-TOF MS).RESULTS: Homogeneous high fluorescence was seen on cholesterol stones either pre-incubated with hypericin or extracted from VGHG rats receiving hypericin. Mixed stones showed a dotted fluorescent pattern, whereas pigment and solvent-treated ones lacked fluorescence. HPLC showed 7.68, 6.65 and 0.08 × 10^(-3) M of cholesterol in extracts from cholesterol, mixed, and pigment gallstones, respectively. Hypericin accounted for 2.0, 0.5 and 0.2 × 10-6 M in that order. On cholesterol stones from VGHG rats receiving different hypericin doses, a positive correlation was observed between dose and fluorescence. In the bile from CBD-cannulated rats, fluorescence represented 20% of the injected dose with two peaks in 9 h. HPLC analysis revealed that hypericin conjugates reached 60% of the peak area. By MALDI-TOF MS, hypericinglucuronide was detected. CONCLUSION: This study proves the potential use of hypericin for differential fluorescent detection of human gallstones regarding their chemical composition.
基金the Cancer Hospital of Peking Union Medical College Hospital,Chinese Academy of Medical Sciences Institutional Review Board(Approval No.20/120-2316).
文摘BACKGROUND Desmoid fibroma is a rare soft tissue tumor originating from the aponeurosis,fascia,and muscle,and it is also known as aponeurotic fibroma,invasive fibroma,or ligamentous fibroma.AIM To investigate the clinical and imaging features of desmoid tumors of the extremities.METHODS Thirteen patients with desmoid fibroma of the extremities admitted to our hospital from October 2016 to March 2021 were included.All patients underwent computed tomography(CT),magnetic resonance imaging(MRI),and pathological examination of the lesion.Data on the diameter and distribution of the lesion,the relationship between the lesion morphology and surrounding structures,MRI and CT findings,and pathological features were statistically analyzed.RESULTS The lesion diameter ranged from 1.7 to 8.9 cm,with an average of 5.35±2.39 cm.All lesions were located in the deep muscular space,with the left and right forearm each accounting for 23.08%of cases.Among the 13 patients with desmoid fibroma of the extremities,the lesions were"patchy"in 1 case,irregular in 10,and quasi-round in 2.The boundary between the lesion and surrounding soft tissue was blurred in 10 cases,and the focus infiltrated along the tissue space and invaded the adjacent structures.Furthermore,the edge of the lesion showed"beard-like"infiltration in 2 cases;bone resorption and damage were found in 8,and bending of the bone was present in 2;the boundary of the focus was clear in 1.According to the MRI examination,the lesions were larger than 5 cm(61.54%),round or fusiform in shape(84.62%),had an unclear boundary(76.92%),showed uniform signal(69.23%),inhomogeneous enhancement(84.62%),and"root"or"claw"infiltration(69.23%).Neurovascular tract invasion was present in 30.77%of cases.CT examination showed that the desmoid tumors had slightly a lower density(69.23%),higher enhancement(61.54%),and unclear boundary(84.62%);a CT value<50 Hu was present in 53.85%of lesions,and the enhancement was uneven in 53.85%of cases.Microscopically,fibroblasts and myofibroblasts were arranged in strands and bundles,without obvious atypia but with occasional karyotyping;cells were surrounded by collagen tissue.There were disparities in the proportion of collagen tissue in different regions,with abundant collagen tissue and few tumor cells in some areas,similar to the structure of aponeuroses or ligaments,and tumor cells invading the surrounding tissues.CONCLUSION Desmoid tumors of the extremities have certain imaging features on CT and MRI.The two imaging techniques can be combined to improve the diagnostic accuracy,achieve a comprehensive diagnosis of the disease in the clinical practice,and reduce the risk of missed diagnosis or misdiagnosis.In addition,their use can ensure timely diagnosis and treatment.
文摘Tissue-classification-based attenuation correction strategies have been previously proposed to correct for bone attenuation in PET/MR imaging and simulated using computed tomography. However, the complication of voxel averaging uniquely associated with bone has not been considered explicitly in the past. This study investigated the effect of voxel averaging between bone and soft tissue in attenuation images and determined how accurately bone must be detected in MR images in order to perform acceptable attenuation correction of PET data by using CT-simulated attenuation correction. We found out that treating bone as soft tissue caused a mean quantification difference of -9.9% ± 5.5% in all 119 bone lesions. There were no significant differences between lesions in the pelvis and the vertebrae. The nominal difference in lesions in the ribs was significantly lower, likely due to the spatial misregistration between the emission and attenuation images. Interestingly, a non-monotonic relationship between the bone imaging ability and the absolute PET quantification accuracy was observed, with the minimal quantification difference achieved at a BVF around 40% for skull lesions (2.6% ± 2.1%), and 30% for non-skull lesions (1.4% ± 1.1%) and all lesions (1.5% ± 1.3%). This study established that a bone classification sensitivity of approximately 30% BVF is required in order for MR-based attenuation correction methods to achieve optimal quantification in whole-body PET/MR studies. For this purpose, higher bone imaging ability of MR may not be necessary.
文摘Objective: To compare and analyze the image quality and radiation dose of three scanning modes of dual-source CT coronary artery retrospectively, and to discuss the application value of TurboFlash coarse pitch scanning mode. Methods: The imaging data of 100 patients who underwent CT coronary angiography (CCTA) using Siemens force CT retrospective gated triggering spiral scan (RES-SPIRAL), adaptive prospective gated triggering sequence scan (SEQ) and prospective coarse pitch scan (TurboFlash) retrospectively was collected. The image quality was evaluated by objective and subjective methods. The effective radiation dose of patients was compared and analyzed, and the indications of the three scanning modes were analyzed. The application value of dual-source CT TurboFlash coarse pitch scanning in coronary artery imaging was evaluated. Results: The results showed that the left main coronary artery, the right coronary artery and their tertiary branches could be clearly displayed in the three groups of images: the left anterior descending branch, the left circumflex branch, and their three-level branches. There was no statistical difference in subjective image quality among the three groups of pictures (P > 0.05). There was no statistical difference in objective evaluation indexes, such as CT value, SNR, CNR and Noise among the three groups (P > 0.05). The patient radiation dose results showed that the effective radiation dose ED of RES-SPIRA scan was (9.22 ± 1.33) mSv. The dose of SEQ was (2.88 ± 2.47) mSv, and the dose of TurboFlash was (0.51 ± 0.16) mSv. There was significant difference in comparison of the three groups (P 0.05). RES-spiral scanning had the highest radiation dose and TurboFlash coarse pitch scanning (TurboFlash) had the lowest radiation dose. Conclusion: TurboFlash coarse pitch scanning is low in dosage, fast in speed and wide in adaptability. It is especially suitable for the elderly, children, coma and other patients who cannot cooperate with breath-holding examination, as well as for the screening and examination of coronary artery diseases in asymptomatic population. Undoubtedly, it is a worthy method of heart coronary artery examination.
