scholarly journals OC11.05: Evaluation of the reproducibility and confounders of FAIR ASL placenta perfusion measurement in normal pregnancies

2021 ◽  
Vol 58 (S1) ◽  
pp. 34-34
Author(s):  
A. Jungelson ◽  
C.J. Arthuis ◽  
C. Henry ◽  
M. Taso ◽  
D. Alsop ◽  
...  
Keyword(s):  
Perfusion Measurement

Neurovascular changes after four-layer compression bandaging in people with chronic venous leg ulcers

2007 ◽  
Vol 22 (2) ◽  
pp. 49-55 ◽  
Author(s):  
R Ogrin ◽  
P Darzins ◽  
Z Khalil
Keyword(s):  
Wound Healing ◽  
Wound Repair ◽  
Statistical Significance ◽  
Sensory Nerve ◽  
Compression Therapy ◽  
Clinical Problem ◽  
Leg Ulcers ◽  
Venous Leg Ulcers ◽  
Perfusion Measurement ◽  
Compression Bandaging

Objectives: Venous leg ulcers represent a major clinical problem, with poor rates of healing. Ideal treatment is compression bandaging. The effect of compression on neurovascular tissues involved in wound repair is unclear. This study aims to assess the effect of four-layer compression therapy (40 mmHg) on neurovascular function and wound healing in people with chronic venous leg ulcers – 15 people (55 years or older) with venous leg ulcers for more than six weeks. Methods: Basal microvascular perfusion measurement (MPM), oxygen tension (tc pO2) measured at sensor temperatures of 39°C and 44°C and sensory nerve function using electrical cutaneous perception thresholds (ECPT) at 5, 250 and 2000 Hz (corresponding to C, A δ and A β fibres) were assessed adjacent to the ulcer site, and at a mirror location on the non-ulcerated limb. Testing was undertaken before and after therapy for 5–12 weeks of four-layer compression bandaging. Results: There was significant improvement in tc pO2 at 44°C and ECPT at 2000 Hz ( P<0.05) compared with pre-intervention. Changes in basal MPM, tc pO2 at 39°C and ECPT at 5 and 250 Hz after compression therapy did not reach statistical significance. Conclusion: Four-layer compression bandaging in people with venous leg ulcers improved some components of neurovascularture in people with chronic venous leg ulcers. Whether this improvement has contributed to wound healing in this study requires further investigation.

scholarly journals B-PO05-064 LASER DOPPLER DERIVED PERIPHERAL PERFUSION MEASUREMENT CAN ASSESS HAEMODYNAMIC STATUS IN VENTRICULAR TACHYCARDIA

Heart Rhythm ◽  
2021 ◽  
Vol 18 (8) ◽  
pp. S397-S398
Author(s):  
Alejandra Andrea Miyazawa ◽  
Ahran D. Arnold ◽  
Matthew J. Shun-Shin ◽  
Daniel Keene ◽  
James P. Howard ◽  
...  
Keyword(s):  
Ventricular Tachycardia ◽  
Laser Doppler ◽  
Peripheral Perfusion ◽  
Perfusion Measurement

scholarly journals Quantitative Perfusion Measurements in a Novel Large Animal Stroke Model

2021 ◽  
Author(s):  
◽  
Alexandra King
Keyword(s):  
Animal Model ◽  
Cause Of Death ◽  
Vasogenic Edema ◽  
Measurement Techniques ◽  
Future Research ◽  
Large Animal ◽  
Dce Mri ◽  
Post Stroke ◽  
Perfusion Measurement ◽  
Parameter Values

<p><b>Stroke is a leading cause of death worldwide [1], and is the third leading cause of death and the leading cause of serious adult disability in New Zealand[2]. The aim of this project was to quantify perfusion changes in the brains of 20 sheep that underwent a novel surgical model of transient ischemic stroke. The sheep, with its large, gyrencephalic brain, presents a promising, potential animal model for stroke that could help to bridge the historical gap in translational research in stroke therapies [3]. However, we require that an animal model can replicate human patterns of disease in order for it to be a meaningful model for research into potential stroke therapies for humans. It was this replication of human patterns of disease, in terms of perfusion, thatwas under investigation in this project. Dynamic Contrast Enhanced (DCE) MRI images were obtained from each animal before stroke, and at 24 hours, 3 days, 6 days, and 28 days post-stroke. It was found that perfusion from the DCE-MRI series was quantifiable using the extended Tofts model in the form of the parameters Ktrans, ve and vp. The parameter values calculated from this project replicate known human patternsof disease in terms of global Ktrans changes in the affected hemisphere [4], which were found to increase by more than 60% in the stroke hemisphere,replicating the increased permeability following blood brain barrier breakdown.</b></p> <p>In manually selected regions of cytotoxic and vasogenic edema, it was found that the estimated parameters in these regions replicated known perfusionchanges in these types of edema in humans [5]. Finally, the peak post-stroke permeability time point, as determined by Ktrans, was found to align exactlywith when we would expect vasogenic edema, a type of cerebral swelling that causes increased barrier permeability, to dominate in humans [5].</p> <p>This thesis is the first time these DCE-MRI datasets have been analysed, and there remains a wealth of physiological and MRI data available forthis animal cohort. Avenues for future research include investigation into perfusion-diffusion mismatch in this animal model, further consideration ofindividual animal characteristics in analysis, and use of these results as a point of comparison for future research into pharmaceutical agents for treatment ofstroke, and in new non-contrast perfusion measurement techniques.</p>

Dynamic Sonographic Tissue Perfusion Measurement with the PixelFlux Method

2008 ◽  
pp. 115-125 ◽  
Author(s):  
Thomas Scholbach ◽  
Jakob Scholbach ◽  
Ercole Di Martino
Keyword(s):  
Tissue Perfusion ◽  
Perfusion Measurement

scholarly journals Establishment of a Swine Model for Validation of Perfusion Measurement by Dynamic Contrast-Enhanced Magnetic Resonance Imaging

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Anika Sauerbrey ◽  
Stefan Hindel ◽  
Marc Maaß ◽  
Christine Krüger ◽  
Andreas Wissmann ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Blood Flow ◽  
Femoral Artery ◽  
Resonance Imaging ◽  
Flow Probe ◽  
Dce Mri ◽  
Perfusion Measurement ◽  
Dynamic Contrast Enhanced ◽  
Contrast Enhanced ◽  
Perfusion Measurements

The aim of the study was to develop a suitable animal model for validating dynamic contrast-enhanced magnetic resonance imaging perfusion measurements. A total of 8 pigs were investigated by DCE-MRI. Perfusion was determined on the hind leg musculature. An ultrasound flow probe placed around the femoral artery provided flow measurements independent of MRI and served as the standard of reference. Images were acquired on a 1.5 T MRI scanner using a 3D T1-weighted gradient-echo sequence. An arterial catheter for local injection was implanted in the femoral artery. Continuous injection of adenosine for vasodilation resulted in steady blood flow levels up to four times the baseline level. In this way, three different stable perfusion levels were induced and measured. A central venous catheter was used for injection of two different types of contrast media. A low-molecular weight contrast medium and a blood pool contrast medium were used. A total of 6 perfusion measurements were performed with a time interval of about 20–25 min without significant differences in the arterial input functions. In conclusion the accuracy of DCE-MRI-based perfusion measurement can be validated by comparison of the integrated perfusion signal of the hind leg musculature with the blood flow values measured with the ultrasound flow probe around the femoral artery.

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