31,127 research outputs found
Recommended from our members
Accomplishments and challenges in stem cell imaging in vivo.
Stem cell therapies have demonstrated promising preclinical results, but very few applications have reached the clinic owing to safety and efficacy concerns. Translation would benefit greatly if stem cell survival, distribution and function could be assessed in vivo post-transplantation, particularly in patients. Advances in molecular imaging have led to extraordinary progress, with several strategies being deployed to understand the fate of stem cells in vivo using magnetic resonance, scintigraphy, PET, ultrasound and optical imaging. Here, we review the recent advances, challenges and future perspectives and opportunities in stem cell tracking and functional assessment, as well as the advantages and challenges of each imaging approach
Recommended from our members
An exploration of the potential utility of fetal cardiovascular MRI as an adjunct to fetal echocardiography
Objectives: Fetal cardiovascular magnetic resonance imaging (MRI) offers a potential alternative to echocardiography, although in practice, its use has been limited. We sought to explore the need for additional imaging in a tertiary fetal cardiology unit and the usefulness of standard MRI sequences.
Methods: Cases where the diagnosis was not fully resolved using echocardiography were referred for MRI. Following a threeâplane localiser, fetal movement was assessed with a balanced steadyâstate free precession (bSSFP) cine. Singleâshot fast spin echo and bSSFP sequences were used for diagnostic imaging.
Results: Twentyâtwo fetal cardiac MRIs were performed over 12âmonths, at mean gestation of 32âweeks (26â38âweeks). The majority of referrals were for suspected vascular abnormalities (17/22), particularly involving the aortic arch (nâ=â10) and pulmonary vessels (nâ=â4). Singleâshot fast spin echo sequences produced âblackâbloodâ images, useful for examining the extracardiac vasculature in these cases. BSSFP sequences were more useful for intracardiac structures. Realâtime SSFP allowed for dynamic assessment of structures such as cardiac masses, with enhancement patterns also allowing for tissue characterisation in these cases.
Conclusions: Fetal vascular abnormalities such as coarctation can be difficult to diagnose by using ultrasound. Fetal MRI may have an adjunctive role in the evaluation of the extracardiac vascular anatomy and tissue characterisation. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd
EFSUMB Recommendations and Guidelines for Gastrointestinal Ultrasound - Part 1: Examination Techniques and Normal Findings (Short version)
Abstract
âŒ
In October 2014 the European Federation of Societies
for Ultrasound in Medicine and Biology formed
a Gastrointestinal Ultrasound (GIUS) task force
group to promote the use of GIUS in a clinical setting.
One of the main objectives of the task force
group was to develop clinical recommendations
and guidelines for the use of GIUS under the auspices
of EFSUMB. The first part, gives an overview of
the examination techniques for GIUS recommended
by experts in the field. It also presents the
current evidence for the interpretation of normal
sonoanatomical and physiological features as examined
with different ultrasound modalities
Pancreatic tumors imaging: an update
Currently, ultrasound (US), computed tomography (CT) and Magnetic Resonance imaging (MRI) represent the mainstay in the evaluation of pancreatic solid and cystic tumors affecting pancreas in 80-85% and 10-15% of the cases respectively. Integration of US, CT or MR imaging is essential for an accurate assessment of pancreatic parenchyma, ducts and adjacent soft tissues in order to detect and to stage the tumor, to differentiate solid from cystic lesions and to establish an appropriate treatment. The purpose of this review is to provide an overview of pancreatic tumors and the role of imaging in their diagnosis and management. In order to a prompt and accurate diagnosis and appropriate management of pancreatic lesions, it is crucial for radiologists to know the key findings of the most frequent tumors of the pancreas and the current role of imaging modalities. A multimodality approach is often helpful. If multidetector-row CT (MDCT) is the preferred initial imaging modality in patients with clinical suspicion for pancreatic cancer, multiparametric MRI provides essential information for the detection and characterization of a wide variety of pancreatic lesions and can be used as a problem-solving tool at diagnosis and during follow-up
EFSUMB Recommendations and Guidelines for Gastrointestinal Ultrasound - Part 1: Examination Techniques and Normal Findings (Long version).
Abstract
âŒ
In October 2014 the European Federation of Societies
for Ultrasound in Medicine and Biology formed
a Gastrointestinal Ultrasound (GIUS) task force
group to promote the use of GIUS in a clinical setting.
One of the main objectives of the task force
group was to develop clinical recommendations
and guidelines for the use of GIUS under the auspices
of EFSUMB. The first part, gives an overview of
the examination techniques for GIUS recommended
by experts in the field. It also presents the
current evidence for the interpretation of normal
sonoanatomical and physiological features as examined
with different ultrasound modalities
Focal Spot, Winter 2006/2007
https://digitalcommons.wustl.edu/focal_spot_archives/1104/thumbnail.jp
Diagnostic accuracy of Doppler ultrasound technique of the penile arteries in correlation to selective arteriography
In 63% of 265 patients with erectile dysfunction a relevant arterial inflow disturbance was found by Doppler ultrasound examination. Correlation between Doppler and arteriography in 58 patients showed an accuracy of 95% in detecting penile arteries and an accuracy of 91% in discovering a pathological arterial pattern (arterial anomaly or arteriosclerotic obstruction). In 15 patients the arterial inflow was measured additionally by Doppler ultrasound technique after intracavernosal injection of vasoactive drugs (IIVD) (7.5 mg papaverine and 0.25 mg phentolamine). This technique proved to be more reliable than in the flaccid state and markedly facilitated localization and assessment of pathological changes of the cavernosal arteries
Single-breath-hold photoacoustic computed tomography of the breast
We have developed a single-breath-hold photoacoustic computed tomography (SBH-PACT) system to reveal detailed angiographic structures in human breasts. SBH-PACT features a deep penetration depth (4âcm in vivo) with high spatial and temporal resolutions (255â”m in-plane resolution and a 10âHz 2D frame rate). By scanning the entire breast within a single breath hold (~15âs), a volumetric image can be acquired and subsequently reconstructed utilizing 3D back-projection with negligible breathing-induced motion artifacts. SBH-PACT clearly reveals tumors by observing higher blood vessel densities associated with tumors at high spatial resolution, showing early promise for high sensitivity in radiographically dense breasts. In addition to blood vessel imaging, the high imaging speed enables dynamic studies, such as photoacoustic elastography, which identifies tumors by showing less compliance. We imaged breast cancer patients with breast sizes ranging from B cup to DD cup, and skin pigmentations ranging from light to dark. SBH-PACT identified all the tumors without resorting to ionizing radiation or exogenous contrast, posing no health risks
- âŠ