Emerging Imaging Techniques

McVeigh, Elliot R.

doi:10.1161/01.res.0000216870.73358.d9

Cited by 61 publications

(21 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…25,26 High-frequency ultrasound (>10 MHz), with its increased spatial resolution compared with conventional diagnostic ultrasound, provides a better tool to overcome limitations in the detection of the LV wall geometric structure and formation in both normal and abnormal muscle. 27 In our experience, the use of frequencies lower than 7.5 MHz did not allow good definition of the endocardial borders in most animals. Indeed, the use of more recent and advanced echocardiographic systems, with 12-MHz transducers, provided better image quality from all planes.…”

Section: Discussionmentioning

confidence: 68%

Wideband High-Frequency Echocardiography to Evaluate Myocardial Infarct Size

Zhang

Khanna

2009

Journal of Ultrasound in Medicine

View full text Add to dashboard Cite

Objective. This study was designed to validate the feasibility of wideband high-frequency ultrasound imaging to resolve in vivo the degree, location, and morphologic changes of myocardial infarction (MI) in a rat model. Methods. The left anterior descending coronary artery was ligated in the test group (n = 41), and the sham control group did not have ligation (n = 7). The rats were examined with 10-to 22-MHz echocardiography to evaluate the MI size, location, and geometric formation. Results. The endocardial chamber shape was deformed, with enlargement of the anteroposterior dimension and fractional shortening, and was comparable with the degree of MI both in short-and long-axis sections of the left ventricle. Histologic analysis showed remodeling to different extents corresponding to different MI sizes (small, medium, and large). Conclusions. The results suggest that this technique can be used in vivo to evaluate the MI location, size, and morphologic changes corresponding to the extent of the injury. Key words: high-frequency ultrasound imaging; histologic analysis; left anterior descending coronary artery; myocardial infarction. he rat is a preferred species for studying the pathophysiologic mechanisms of myocardial infarction (MI), cardiomyopathy, and other cardiovascular diseases. 1,2 Noninvasive in vivo study of rat cardiac structure and function has attracted interest in cardiovascular research, especially those involving the left ventricle (LV). The rat infarct model has been used extensively to study LV dysfunction after MI and in the evaluation of experimental therapies for heart failure. 3,4 Two-dimensional (2D) B-mode, M-mode, and Doppler ultrasound have been used to evaluate LV structural and functional remodeling in humans for decades, particularly in patients with MI during the acute phase and for later follow-up. However, the small size and rapid heart rate (300-500 beats per minute) of the rat heart demand an imaging modality with both high temporal resolution and high spatial resolution. 5,6 Recently developed high-resolution echocardiographic systems with high frequencies (>20 MHz) are particularly well suited for the study of the heart in rodent models of MI. These systems can be used for evaluating the heart contractility, mainly LV systolic and diastolic function.

show abstract

Section: Discussionmentioning

confidence: 68%

Wideband High-Frequency Echocardiography to Evaluate Myocardial Infarct Size

Zhang

Khanna

2009

Journal of Ultrasound in Medicine

View full text Add to dashboard Cite

show abstract

“…Several criteria are used to determine TEBV function: i) mechanical compatibility, including elasticity, suture retention, burst pressure and compliance, to ensure graft endurance of dynamic changes, while avoiding mechanical mismatch that could lead to graft failure [72,73]; ii) cell distribution to achieve a monolayer of EC in the intimal layer, SMC in the medial layer [60] and FB in the adventitial layer, as well as appropriate cellular response to external stimulation [64,74]; iii) functional compatibility, including patency and flow profile to avoid hyperplasia, aneurism or plaque formation after implantation [31,44,75]. The maturation of TEBV in vivo is a complex process that requires a set of chemical and physical stimulations to control scaffold degradation and reorganization of ECs and SMCs [76,77].…”

Section: Tebv Assessmentmentioning

confidence: 99%

Bioengineered blood vessels

Niu

Sapoznik

Söker

2014

Expert Opinion on Biological Therapy

View full text Add to dashboard Cite

“…[7][8][9][10] Dyes that emit NIR light have been used to assess perfusion of cardiac vessels intraoperatively. 2,4,[11][12][13] Although these dyes are useful for detecting stenosis and obstruction, they have only modest sensitivity for thrombus detection and cannot distinguish evolving clots from stabilized clots. New approaches that can detect thrombus formation in vessels that approximate the size of human coronary, carotid, and femoral vessels are required to study thrombus formation in large animal models and to detect thrombi during vascular procedures.…”

Section: Clinical Perspective P 93mentioning

confidence: 99%

“…[1][2][3][4][5] The fundamental advantage of imaging in the NIR range is that photon penetration into living tissue is higher because of lower photon absorption and scatter. 6 An additional advantage is that tissue emits limited intrinsic fluorescence (ie, autofluorescence) in the 700-to 900-nm range.…”

mentioning

confidence: 99%

Localization and Quantification of Platelet-Rich Thrombi in Large Blood Vessels With Near-Infrared Fluorescence Imaging

et al. 2007

View full text Add to dashboard Cite

Background-Imaging of thrombus formation in vivo has been limited by the inability to directly visualize and measure thrombi in large blood vessels in real time. Near-infrared light, with its superior tissue penetration and reduced scatter, could potentially solve this problem. Methods and Results-Platelets were labeled with the near-infrared fluorophore IR-786. Optimal total fluorescence yield occurred at 6 attomoles of IR-786 per platelet. IR-786 -labeled platelets were tested for their ability to detect thrombus formation in large animal model systems relevant to common human vascular procedures. Invisible near-infrared light did not distort the surgical field in any way, and even after optimization of per-platelet fluorescent yield, platelets remained fully functional. Intravenous infusion of just 3.6ϫ10 10 labeled platelets into a 35-kg Yorkshire pig permitted thrombus visualization, with a signal-to-background ratio Ն2, for at least 2 hours in coronary, carotid, and femoral vessels. Platelet-rich, actively growing clots were monitored in real time and quantified with respect to size and kinetics after injury to vessels, cutaneous incisions, intravascular stent insertion, or introduction of embolic coils. Similarly, formed clots were monitored in real time during thrombolysis with streptokinase and heparin. Vessel patency was assessed independently with a second near-infrared fluorescent blood pool agent. Conclusions-IR-786 -labeled platelets provide sensitive, specific, and real-time visualization of thrombi in thick-walled blood vessels. In addition to immediate application in cardiac, transplant, and vascular surgery, the mechanisms that underlie thrombus formation in large blood vessels can now be investigated.

show abstract

Emerging Imaging Techniques

Cited by 61 publications

References 53 publications

Wideband High-Frequency Echocardiography to Evaluate Myocardial Infarct Size

Wideband High-Frequency Echocardiography to Evaluate Myocardial Infarct Size

Bioengineered blood vessels

Localization and Quantification of Platelet-Rich Thrombi in Large Blood Vessels With Near-Infrared Fluorescence Imaging

Contact Info

Product

Resources

About