1.Percutaneous mitral valve repair with MitraClip for severe functional mitral regurgitation.
Khung Keong YEO ; Zee Pin DING ; Yeow Leng CHUA ; Soo Teik LIM ; Kenny Yoong Kong SIN ; Jack Wei Chieh TAN ; Paul Toon Lim CHIAM ; Nian Chih HWANG ; Tian Hai KOH
Singapore medical journal 2013;54(1):e9-e12
A 67-year-old Chinese woman with comorbidities of chronic obstructive lung disease, hypertension and prior coronary artery bypass surgery presented with severe functional mitral regurgitation (MR) and severely depressed left ventricular function. She was in New York Heart Association (NYHA) Class II-III. Due to high surgical risk, she was referred for percutaneous treatment with the MitraClip valve repair system. This procedure is typically performed via the femoral venous system and involves a transseptal puncture. A clip is delivered to grasp the regurgitant mitral valve leaflets and reduce MR. This was performed uneventfully in our patient, with reduction of MR from 4+ to 1+. She was discharged on post-procedure Day 2 and her NYHA class improved to Class I. This was the first successful MitraClip procedure performed in Asia and represents a valuable treatment option in patients with severe MR, especially those with functional MR or those at high surgical risk.
Aged
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Cardiac Surgical Procedures
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methods
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Cardiology
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instrumentation
;
methods
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Catheters
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Echocardiography
;
methods
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Equipment and Supplies
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Female
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Heart Ventricles
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physiopathology
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Humans
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Mitral Valve
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surgery
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Mitral Valve Insufficiency
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surgery
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Pulmonary Disease, Chronic Obstructive
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complications
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Risk
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Ultrasonography, Doppler
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methods
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Ventricular Dysfunction, Left
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surgery
2.Diagnostic value of ultrasonography in combination with mammography for breast cancer within 2 cm: a meta-analysis.
Huan LIN ; Hansheng LIN ; Hong LIANG
Journal of Southern Medical University 2013;33(11):1699-1703
OBJECTIVETo evaluate the diagnostic value of ultrasonography in combination with mammography for breast cancer within 2 cm.
METHODSThe PubMed, the Cochrane Library, CNKI, CBM and Wanfang databases (2003/01/01-2013/04/30) were searched for studies of the diagnostic value of ultrasonography in combination with mammography for breast cancer within 2 cm. The quality of the included studies was evaluated according to QUADAS items. The pooled sensitivity (SEN), pooled specificity (SPE), pooled diagnostic odds ratio (DOR), and area under summary receiver operating characteristic curve (AUC) were calculated using Review Manager 5.2 and Meta-DiSc 1.4 software.
RESULTSNine articles were included in the final analysis. The pooled SEN of ultrasonography, mammography and their combination were 0.75, 0.66, and 0.92, the pooled SPE 0.75, 0.83, and 0.82, the pooled DOR 7.11, 8.67, and 60.82, and the AUC 0.7902, 0.8120, and 0.9469, respectively.
CONCLUSIONThe combination of ultrasonography and mammography can increase the diagnostic accuracy for breast cancer within 2 cm.
Breast Neoplasms ; diagnostic imaging ; pathology ; Early Detection of Cancer ; Female ; Humans ; Mammography ; instrumentation ; methods ; Molybdenum ; ROC Curve ; Sensitivity and Specificity ; Ultrasonography, Doppler, Color ; Ultrasonography, Doppler, Pulsed ; Ultrasonography, Mammary ; methods
3.Echocardiography in Transcatheter Aortic Valve Implantation and Mitral Valve Clip.
The Korean Journal of Internal Medicine 2012;27(3):245-261
Transcatheter aortic valve implantation and transcatheter mitral valve repair (MitraClip) procedures have been performed worldwide. In this paper, we review the use of two-dimensional and three-dimensional transesophageal echo for guiding transcatheter aortic valve replacement and mitral valve repair.
Aged
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Aged, 80 and over
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Aortic Valve Stenosis/*therapy/*ultrasonography
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Balloon Valvuloplasty
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Bioprosthesis
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*Cardiac Catheterization/adverse effects/instrumentation
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*Echocardiography
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Echocardiography, Doppler, Color
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Echocardiography, Three-Dimensional
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Echocardiography, Transesophageal
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Heart Valve Prosthesis
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Heart Valve Prosthesis Implantation/adverse effects/instrumentation/*methods
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Humans
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Mitral Valve Insufficiency/*therapy/*ultrasonography
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Predictive Value of Tests
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Prosthesis Design
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Severity of Illness Index
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Surgical Instruments
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Ultrasonography, Interventional/*methods
4.Neonatal ovarian cysts: role of sonography in diagnosing torsion.
Dinesh CHINCHURE ; Chiou Li ONG ; Amos H P LOH ; Victor S RAJADURAI
Annals of the Academy of Medicine, Singapore 2011;40(6):291-295
INTRODUCTIONThe purpose of this case series was to determine the sonographic features of neonatal ovarian torsion.
MATERIALS AND METHODSSeven surgically proven cases of neonatal ovarian cysts were included in this retrospective study. The patients were divided into 2 groups, torsion and non-torsion. These 7 patients were evaluated for the clinical presentation, sonographic features, surgical and pathological findings. The findings on follow-up sonography after surgery were also noted.
RESULTSThe sonographic appearance was variable. Of the 4 cases with torsion, 2 lesions had internal echoes with 'fi sh-net appearance'. The other 2 lesions were predominantly cystic on the sonography with internal echoes and echogenic nodule. A calcific focus was present in 1 of these echogenic nodules. One of the cysts had fluid-fluid level. In the non-torsion group, only 1 lesion had mixed echogenic appearance. The other 2 lesions were cystic with low level internal echoes in 1 of the cysts. The surgical procedure performed in the torsion group was salpingo-oophorectomy in 2 patients and oophorectomy in 1 patient. In 1 patient, cystectomy was attempted without success. In the non-torsion group, only cystectomy was performed with preservation of normal ovaries, which was confirmed on follow-up sonography.
CONCLUSIONThe sonographic features of cysts with 'fish-net appearance', fluid-debris level and cysts with echogenic nodule favour torsion. The former sign has so far not been described as a sonographic predictor for neonatal ovarian torsion.
Female ; Humans ; Infant, Newborn ; Ovarian Cysts ; diagnostic imaging ; pathology ; surgery ; Ovary ; diagnostic imaging ; pathology ; Postoperative Period ; Retrospective Studies ; Torsion Abnormality ; diagnostic imaging ; pathology ; surgery ; Ultrasonography, Doppler ; instrumentation
5.Study of the beam field of a new array ultrasound transducer.
Xicheng XIE ; Baikun XU ; Dewei CHEN
Chinese Journal of Medical Instrumentation 2010;34(4):250-254
This paper provides a new design of 12-element array ultrasound transducer. By modeling the beam field model of single element and array and comparing simulated and real ultrasound beam field test data, it can be demonstrated that 12-element array ultrasound transducer has a much better field performance than the 8-element transducer.
Equipment Design
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Ultrasonography, Doppler
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instrumentation
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Ultrasonography, Prenatal
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instrumentation
6.Design and implementation of projection-initialized wall filter in ultrasonic imaging.
Peidong WANG ; Yi SHEN ; Yan WANG
Journal of Biomedical Engineering 2008;25(2):300-303
Wall filtering is a key technology in ultrasound color flow imaging system. Without efficient suppression of wall signal originating from stationary and moving tissue, low velocity blood flow cannot be measured, and the estimates of higher velocities will have a large bias. Among the various wall filters, the projection-initialized infinite impulse response (IIR) wall filter has narrow transition bandwidth and high stopband suppression ratio; it is superior to other wall filters. At present, the related literatures are only limited to theoretical research on this kind of filter, and no feasible design and implementation methods are reported. In this paper, a new design and implementation scheme for the projection-initialized filter is proposed, which transforms the filtering process to matrix multiplications. The proposed scheme is realized on programmable logic devices. Experimental results show that it is a simple and effective implementation method for projection-initialized IIR filter, and it is superior to conventional wall filters.
Algorithms
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Blood Flow Velocity
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physiology
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Blood Vessels
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diagnostic imaging
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Computer Simulation
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Equipment Design
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Image Interpretation, Computer-Assisted
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Signal Processing, Computer-Assisted
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Ultrasonography, Doppler, Color
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instrumentation
;
methods
7.Preliminary study of the value of contrast-enhanced ultrasound with high-frequency linear-array transducer in the diagnosis of carotid stenosis.
Journal of Southern Medical University 2008;28(7):1285-1288
OBJECTIVETo study the value of contrast-enhanced ultrasound with high-frequency linear-array transducer in the diagnosis of carotid stenosis.
METHODSThe carotid arteries of 31 patients was examined with color Doppler ultrasound (CDU), harmonic contrast ultrasound (HCU) and digital subtractive angiography (DSA), respectively. The result of DSA was used as the golden standard for evaluating the accuracy, sensitivity and specificity of CDU and HCU in the diagnosis of carotid stenosis.
RESULTSSatisfactory images of 62 carotid arteries were obtained from the patients using HCU with high-frequency linear-array transducer. After intravenous injection of contrast agent, densely dotted hyperechogenic signals were found in the vascular lumen, with stronger intensity than that of the vascular walls. The filling defect areas in the lumen indicated vascular stenosis. Thirty carotid stenoses were detected by DSA, and 25 by CDU. The accuracy, sensitivity and specificity of CDU was 83.3%, 82.0% and 84.9%, respectively. HCU identified 29 carotid stenoses with accuracy, sensitivity and specificity of 96.7%, 96.7% and 97.0%, respectively, significantly higher than those of CDU (P<0.05).
CONCLUSIONHCU with high frequency linear-array transducer has better the accuracy than CDU and may serve as a good alternative for diagnosis of carotid stenosis.
Aged ; Angiography, Digital Subtraction ; Carotid Arteries ; diagnostic imaging ; Carotid Stenosis ; diagnosis ; Female ; Humans ; Image Enhancement ; Male ; Middle Aged ; Transducers ; Ultrasonography, Doppler, Color ; instrumentation ; methods
8.A real-time flow velocity estimation applied to ultrasound color display.
Jianqi DENG ; Dongquan LIU ; Jiliu ZHOU
Journal of Biomedical Engineering 2007;24(3):530-533
In this paper the theory of autocorrelation algorithm for color flow mapping is analyzed and a new way for ultrasound color flow velocity estimation and real-time display is proposed. The method sets up a mapping table which directly relates to the dynamic display range and has only 256 entries using an inverse mapping method instead of calculating the arctangent value directly. This method is ideal for software implementation and offers an interactive way to the user for changing the dynamic range of flow velocity and thus to increasing the display resolution.
Algorithms
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Blood Flow Velocity
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Humans
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Pulsatile Flow
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physiology
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Rheology
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instrumentation
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Ultrasonography, Doppler, Color
;
instrumentation
;
methods
9.A new MTI scheme in ultrasonic color flow mapping systems.
Naizhang FENG ; Jianqiu ZHANG ; Yi SHEN
Journal of Biomedical Engineering 2006;23(2):413-418
In color flow imaging systems, the ultrasound Doppler signal scattered from blood is heavily corrupted by the strong clutter signal reflected from the slow-moving muscular tissue. Moving target indicator (MTI) is a key technique of rejecting the clutter signal and detecting blood flow. To improve the performance of detecting blood flow, a new MTI scheme is proposed in this paper. It consists of a pre-filter, a clutter weak-rejector and a 2-order AR estimator. After the processing of pre-filtering and clutter weak-rejection, the strong clutter signal is effectively eliminated and its strength is comparable with blood flow. Under such condition, the optimal performance can be attained by the 2-order AR estimator. It is illustrated in the simulation that, compared with the data from traditional methods, the blood flow parameters are estimated with smaller deviation and the lower speed flow is detected.
Blood Flow Velocity
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Equipment Design
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Humans
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Image Interpretation, Computer-Assisted
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instrumentation
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methods
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Ultrasonography, Doppler, Color
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instrumentation
;
methods
10.Study on the method of testing the wall filter performance.
Naizhang FENG ; Jianqiu ZHANG ; Yi SHEN
Journal of Biomedical Engineering 2006;23(1):196-199
In order to test the performance of wall filters, we propose a method for simulation of Hybrid Doppler testing signal, which adopts a rectangular power spectrum. In the method, the parameters of clutter, blood flow and system noise can be adjusted with flexibility. The problem about choosing model parameters is discussed as an emphasis. Several reasonable and typical parameter combination patterns are presented. Furthermore, an example is given to explain the process of choosing the parameters and testing the wall filter performance.
Blood Flow Velocity
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physiology
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Computer Simulation
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Humans
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Rheology
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instrumentation
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methods
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Signal Processing, Computer-Assisted
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Ultrasonography, Doppler, Color
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instrumentation
;
methods

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