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The histologic analysis of gastrointestinal stromal tumors (GISTs) is a common method to detect the mitotic activity and to subsequently determine the risk of GISTs for malignancy. The potential false negative error due to inadequate yield of specimens and actual determination of malignancy risk requires analysis of the whole tumor. We aimed to assess the role of contrast enhanced endoscopic ultrasound (CE-EUS) in the management of GISTs. Two authors individually did review of English literatures to identify nine peer-reviewed original articles using keywords- contrast endoscopic ultrasound, GIST and submucosal tumor. Studies were heterogeneous in their aims looking either at differentiating submucosal lesions from GISTs, estimating malignant potential of GISTs with histologic correlation or studying the role of angiogenesis in malignant risk stratification. CE-EUS had moderate to high efficacy in differentiating GISTs from alternative submucosal tumors. CE-EUS had a higher sensitivity than EUS-guided fine needle aspiration, contrast computed tomography and Doppler EUS for detection of neo-vascularity within the GISTs. However, the evidence of abnormal angiogenesis within GIST as a prognostic factor needs further validation. CE-EUS is a non-invasive modality, which can help differentiate GISTs and provide valuable assessment of their perfusion patterns to allow better prediction of their malignant potential but more experience is needed.
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Biopsy, Fine-Needle , Diagnosis , Gastrointestinal Stromal Tumors , Methods , Perfusion , UltrasonographyABSTRACT
PURPOSE: To evaluate the effects of the deviation from the mid-sagittal plane, fetal image size, tissue harmonic imaging (THI), and speckle reduction filter (SRF) on the measurement of the nuchal translucency (NT) thickness using Volume NT(TM) software. MATERIALS AND METHODS: In 79 pregnant women, NT was measured using Volume NT(TM). Firstly, the three-dimensional volumes were categorized based on the angle of deviation in 10degrees intervals from the mid-sagittal plane. Secondly, the operator downsized the fetal image to less than 50% of the screen (Method A) and by magnifying the image (Method B). Next, the image was magnified until the fetal head and thorax occupied 75% of the screen, and the NT was measured (Method C). Lastly, NT values were acquired with THI and SRF functions on, with each function alternately on, and with both functions off. RESULTS: The mean differences in NT measurements were -0.09 mm (p<0.01) between two-dimensional (2D) and a deviation of 31-40degrees and -0.10 mm (p<0.01) between 2D and 41-50degrees. The intraclass correlation coefficients (ICC) for 2D-NT and NT according to image size were 0.858, 0.923, and 0.928 for methods A, B, and C, respectively. The ICC for 2D-NT and NT with respect to the THI and SRF were 0.786, 0.761, 0.740, and 0.731 with both functions on, THI only, SRF only, and with both functions off, respectively. CONCLUSION: NT measurements made using Volume NT(TM) are affected by angle deviation from the mid-sagittal plane and fetal image size. Additionally, the highest correlation with 2D-NT was achieved when THI and SRF functions were used.
Subject(s)
Adult , Female , Humans , Pregnancy , Embryo, Mammalian/diagnostic imaging , Image Enhancement/methods , Imaging, Three-Dimensional/methods , Nuchal Translucency Measurement/methods , Sensitivity and Specificity , SoftwareABSTRACT
In the last 30 years, technical improvements have directly contributed to expanding sonographic breast imaging applications into the most important adjunctive imaging modality for breast evaluation. Most of these advances have related to improvements in sonographic gray-scale image resolution and contrast, but some applications such as color Doppler imaging, elastography, optical imaging, or three-dimensional ultrasounds have resulted in sonographic information that is uniquely different from grayscale imaging. The current spectrum of new breast sonographic techniques not only offers information uniquely different from gray-scale imaging but also involves hardware advances that affect the method of image production. In this article, we discuss the current trends in breast ultrasonography focusing on the advances to further improve accuracy for breast lesion diagnosis.
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Breast , Elasticity Imaging Techniques , Optical Imaging , Ultrasonography, MammaryABSTRACT
When insonated with fundamental frequency, the ultrasound contrast microbubbles are able to produce nonlinear scattering and generate nonlinear frequencies. The nonlinear properties of these microbubbles can be used to create nonlinear imaging modality and significantly improve the diagnostic capability of medical ultrasound. This paper was a review about the current research progress of nonlinear properties of ultrasound contrast microbubbles and nonlinear imaging, especially about the nonlinear properties under different frequency, acoustic pressure and the application of nonlinear imaging. A prospect of the future research and application was finally put forward in the paper.
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BACKGROUND: Spontaneous echo contrast (SEC) has been considered as a predisposition to thromboembolism and cerebrovascular accident. However, there have been few reports on the prevalence and role of SEC in dilated cardiomyopathy (DCM). The aim of this study was to investigate the prognostic usefulness of SEC in predicting a stroke in patients with DCM. METHODS: Between October 2001 and January 2008, transthoracic echocardiography with tissue harmonic imaging (THI) was performed for recognition of SEC in patients with DCM. Patients were divided into 2 groups according to the presence of SEC. Clinical characteristic data, echocardiographic parameters were compared between two groups. RESULTS: In this retrospective study, 220 patients (136 men, age 62.8+/-15.4 years) with DCM (left ventricular ejection fraction 27.8+/-7.8%) were included. SEC in the left ventricle (LV) was observed in 24 patients (10.9%). Stroke occurred in 4 (16.7%) of patients with SEC and in 9 (4.6%) of patients without SEC. There were no differences in LA dimension (p=0.24) and LV end-diastolic dimension (p=0.88) between both groups. On univariate analysis, SEC and coronary heart disease at presentation had statistical significance of risk factors for stroke in these groups (p<0.05). On multivariate analysis, only SEC was an independent predictor for stroke (OR 4.393, 95% CI 1.116-17.290, p=0.03). CONCLUSION: These results suggest that SEC by THI through transthoracic echocardiography has a strong association with stroke in patients with DCM. Therefore, this study may help in the risk stratification of cardiac embolism in patients with DCM.
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Humans , Male , Cardiomyopathy, Dilated , Coronary Disease , Echocardiography , Embolism , Heart Ventricles , Multivariate Analysis , Prevalence , Retrospective Studies , Risk Factors , Stroke , Stroke Volume , ThromboembolismABSTRACT
The focal hepatic lesion caused by local injection of absolute alcohol in rats was evaluated with ultrasonic contrast agent and pathologic examination. Twenty adult Wistar rats weighing about 200 g were injected with absolute alcohol (0.05-0.1 mL each one) on the exterior left lobe of the liver under the monitoring of ultrasound. Pulse inversion harmonic imaging was used to evaluate the focal lesion after bolus injection of ultrasonic contrast agent (0.05 mL/200 g) through caudal vein.Seven days later, the focal lesion was studied again as before. The exterior left lobe of liver with focal lesion was incised and underwent pathologic examination. The results showed that all of the focal lesions could be defined clearly after bolus injection of the ultrasonic contrast agent under the mode of pulse inversion harmonic imaging. There was good correlation between the size of the focal lesion measured by ultrasound on the 7th day after the "ablation" under the mode of pulse inversion harmonic imaging and that gotten by pathologic examination (P=0.39). The focus size measured by ultrasound right after the ablation was larger than that gotten by pathologic examination (P= 0.002). It was concluded that ultrasonic contrast agent plus pulse inversion harmonic imaging could be used to assess the size of the focal hepatic lesion caused by local injection of absolute alcohol in rats.
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The clinic main application of medical ultrasonic techniques are introduced,including ophthalmology,neurology,angiology,cardiopathy,digestive system,urology,gynaecology and obstetrics,and surgery. Four kinds of medical ultrasonic techniques in the value on the clinic diagnosis are important,namely transcranial color -coded duplex sonography(TCCD),tissue harmonic imaging(THI),three dimensional imaging(3D),and extended field Of view(EFV).
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0.05) before and after the contrast.However,for the renal parenchyma,it increased significantly after the contrast(P
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Ultrasonic imaging diagnostic technique is one of the most widely used imaging diagnostic techniques,whose fast development has greatly raised the level of clinical diagnosis.The development of ultrasonic imaging diagnostic technique is mainly introduced and various kinds of ultrasonic imaging diagnostic techniques are mentioned including A-mode,M-mode and B-mode ultrasonic diagnostic techniques,Doppler imaging technique,3D imaging technique and harmonic imaging technique.
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OBJECTIVE: To determine the usefulness of tissue harmonic imaging (THI) and pulse-inversion harmonic imaging (PIHI) in the evaluation of normal and abnormal fetuses. MATERIALS AND METHODS: Forty-one pregnant women who bore a total of 31 normal and ten abnormal fetuses underwent conventional ultrasonography (CUS), and then THI and PIHI. US images of six organ systems, namely the brain, spine, heart, abdomen, extremities and face were compared between the three techniques in terms of overall conspicuity and the definition of borders and internal structures. RESULTS: For the brain, heart, abdomen and face, overall conspicuity at THI and PIHI was significantly better than at CUS (p < 0.05). There was, though, no significant difference between THI and PIHI. Affected organs in abnormal fetuses were more clearly depicted at THI and PIHI than at CUS. CONCLUSION: Both THI and PIHI appear to be superior to CUS for the evaluation of normal or abnormal structures, particularly the brain, heart, abdomen and face.
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BACKGROUND: Paradoxical embolism through the patent foramen ovale (PFO) is a well-recognized mechanism for otherwise unexplained ischemic stroke. Although transthoracic contrast echocardiography (TCE) has been used frequently for noninvasive diagnosis of right to left shunt through PFO, its diagnostic accuracy appears limited, especially in patients with poor acoustic window. Since harmonic imaging (HI) can enhance the definition of contrast microbubbles, theoretical advantages of HI in the detection of right to left shunt through PFO using microbubbles can be considered. However, there are few data regarding the diagnostic efficacy of HI in the detection of right to left shunt through PFO. The purpose of this study was to compare the diagnostic value of transthoracic HI in the detection of right to left shunt through PFO in patients with stroke with that of fundamental imaging (FI). Methods: One hundred thirty-six consecutive patients with stroke (82 male, mean age:9) underwent TCE in both HI and FI and transesophageal echocardiography (TEE) during rest and Valsalva maneuver with intravenous administration of agitated saline. PFO was judged to be present if microbubbles appeared in the left atrium within 3 cardiac cycles of their appearance in the right atrium. TEE was regarded as the gold standard for assessing the diagnostic accuracy of TCE. Results: Right to left shunt through PFO was detected in 40 of 136 patients by TEE (29.4%). FI of TCE detected shunt through PFO in only 9 of 136 patients (6.6%). In contrast, HI detected shunt through PFO in 25 of 136 patients (18.4%). The overall sensitivity and specificity of FI and HI for detection of right to left shunt through PFO were 22.5%, 62.5% (p<0.05) and 100%, 100%, respectively. Valsalva maneuver during HI significantly increased the detection rate of shunt through PFO (during rest in 9 and during Valsalva maneuver in 25, p<0.05). CONCLUSION: HI with contrast microbubble injection significantly enhanced the detection of right to left shunt through PFO in patients with ischemic stroke compared with FI by transthoracic approach.
Subject(s)
Humans , Male , Acoustics , Administration, Intravenous , Diagnosis , Dihydroergotamine , Echocardiography , Echocardiography, Transesophageal , Embolism, Paradoxical , Foramen Ovale, Patent , Heart Atria , Microbubbles , Sensitivity and Specificity , Stroke , Valsalva ManeuverABSTRACT
OBJECTIVE: The object of this study was to assess the accuracy of dipyridamole stress intravenous (IV) myocardial contrast echocardiography (MCE) using pulse inversion harmonic imaging and PESDA in the detection of perfusion defect in the patients with coronary artery disease in comparison with dipyridamole stress Tc-99m sestamibi SPECT. METHODS: Total 46 patients (29 males, mean age 64 years old) were consecutively enrolled. Patients with prior myocardial infarction were excluded. MCE and Tc-99m sestamibi SPECT were performed at the same day during rest and after 0.56 or 0.84mg/Kg dipyridamole infusion. Continuous IV infusion of PESDA (2-5 mL/min) was administered while obtaining triggered (1:1) end-systolic apical 2, 4 chamber and long axis views. Tc-99m sestamibi was injected 3 minutes after dipyridamole. Tc-99m sestamibi SPECT images were obtained one hour later. Coronary angiography was followed within two days in all patients. Tc-99m sestamibi SPECT images were matched to the sixteen segments of left ventricle according to American Society of Echocardiography for segmental comparison. Both images were analyzed visually. Results Using coronary angiography as the standard, MCE showed overall sensitivity of 70.7%, specificity of 95.8%, positive predictive value (PPV) of 87.8% and negative predictive value (NPV) of 88.5% in the detection of coronary atherosclerosis (70% stenosis). Tc-99m sestamibi SPECT showed sensitivity of 75.6%, specificity of 98.9%, PPV of 96.8% and NPV of 90.6%. The overall concordance rate between MCE and Tc-99m sestamibi SPECT for the detection of perfusion defects was 86.9% (Cohen's kappa value 0.63) according to the coronary territory and 86.8% (Cohen's kappa value 0.55) according to segmental analysis. CONCLUSION: Dipyridamole stress IV MCE using pulse inversion harmonic imaging and PESDA is feasible and comparable to Tc-99m sestamibi SPECT in identifying significant coronary stenosis and inducible myocardial perfusion defects in the patients with coronary artery disease. MCE using pulse inversion harmonic imaging seems to be a promising modality for assessing myocardial perfusion in the patients with suspected coronary artery disease.
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Humans , Male , Axis, Cervical Vertebra , Coronary Angiography , Coronary Artery Disease , Coronary Stenosis , Dipyridamole , Echocardiography , Heart Ventricles , Myocardial Infarction , Perfusion , Sensitivity and Specificity , Tomography, Emission-Computed, Single-PhotonABSTRACT
BACKGROUND: Assessment of segmental wall motion is one of the most challenging tasks in echocardiography. The diagnosis of ischemic heart disease by echocardiography depends on the accurate detection of segmental wall motion abnormalities. However, echocardiographic regional wall motion analysis is impaired by incomplete endocardial definition due to obesity, chronic obstructive lung disease, etc. The purpose of this study was to examine the value of tissue harmonic imaging for endocardial border definition. METHODS: We recorded echocardiograms in 30 consecutive patients, in which more than one segment of left ventricule were poorly visualized, by ATL HDI 3000 and analyzed left ventricular segmental wall motion and then recorded echocardiograms again by tissue harmonic imaging (THI) technique. Endocardial border definition for each segment was graded from grade A to C (grade A in which endocardium is clearly visualized, grade B in which endocardium is poorly visualized and grade C in which endocardium is not seen). Densitometric analysis was perfromed in 10 randomly selected patients. Mean density and dynamic range in histogram were obtained at septum, posterior wall and left ventricle cavity on parasternal long axis view with both techniques. RESULTS: Among total 480 segments, 237 segments (49.4%) were categorized as grade A, 152 segments (31.7%) were categorized as grade B and 91 segments (18.9%) were categorized as grade C in fundamental modes. However, 380 segments (79.2%) were categorized as grade A, 75 segments (15.6%) were categorized as grade B and 25 segments (5.2%) were categorized as grade C in tissue harmonic modes. Visualization of 37.7% (181 segments/480 segments) of all segments was improved in tissue harmonic imaging, with 5.2% (25 segments/480 segments) improved from "not seen" to "clearly visualized". Of these improved 181 segments in THI, 105 segments (58%) were the lateral and anterior walls on apical views. In densitometric analysis of septum, wall density and delta density (wall densityLV cavity density) were significantly higher in THI than fundamental modes (p<0.05). But, W/C ratio (wall density/LV cavity density) was not different between two imaging modalities. In densitometric analysis of posterior wall, all parameters were not significantly different between two imaging modalities. Also, W/C ratio of dynamic range (posterior wall dynamic range/LV cavity dynamic range) was not significantly different between two imaging modalities. CONCLUSION: Tissue harmonic imaging has significant value in endocardial border definition in the patients with poor echocardiographic windows and appears promising with the added advantage of no requirement for intravenous access.
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Humans , Axis, Cervical Vertebra , Diagnosis , Echocardiography , Endocardium , Heart Ventricles , Myocardial Ischemia , Obesity , Pulmonary Disease, Chronic ObstructiveABSTRACT
BACKGROUND: Although myocardial contrast 2D echocardiography is a good method to diagnose and evaluate myocardial ischemia and reperfusion, it has required intracoronary or intra aortic root injection of contrast agent and furthemore, the degree of myocardial contrast produced is small. Second harmonic imaging which is based on the non linear emission of harmonics by resonant microbubble in the ultrasound field improves the ultrasound contrast single to noise ratio. METHODS: We measure the videointensity of interventricular septum(IVS) and lateral wall(LW) of second harmonic imaging myocardial contrast 2D echocardiography before and after LV injection of Levovist(300mg/ml, 0.4ml/Kg) in both pre and post left anterior descending coronary artery(LAD) ligation in 7 open chest pigs. RESULTS: 1) The mean(+/-SD) pre LAD ligation videointensity is significantly greater with after contrast than before contrast(IVS : 111.1+/-33.9 vs 31.1+/-7.6 ; p=0.00046, LW : 120.5+/-21.5 vs 42.2+/-10.0 ; p=0.00006). The post LAD ligation videointensity is also significantly greater with after contrast than before contrast(IVS : 62.8+/-24.6 vs 35.6+/-15.1 ; p=0.00379, LW : 129.9+/-10.9 vs 48.7+/-21.1 ; p=0.00006). 2) The videointensity of IVS is significantly greater with after contrast than before contrast in both pre and post LAD ligation(62.8+/-24.6 vs 111.1+/-33.9 ; p=0.0031). The post LAD ligation videointensity of LW after contrast is not different from that of pre LAD ligation(129.9+/-10.9 vs 120.5+/-21.5 ; p=0.1037). 3) The post LAD ligation videointensity increase of IVS is lower than pre LAD ligantion videointensity increase(27.2+/-18.3 vs 79.9+/-35.0 ; p=0.0006). But the videointensity increase of LW is not different between pre and post LAD ligation(78.2+/-23.4 vs 81.2+/-24.5 ; p=0.3778). CONCLUSION: These findings indicate that the myocardial blood flow and its decrease due to LAD ligation can be evaluated accurately by second harmonic imaging myocardial contrast 2D echocardiography.