The Application of Contrast Media for In Vivo Feature Enhancement in X-Ray Computed Tomography of Soil-Grown Plant Roots

AbstractThe use of in vivo X-ray microcomputed tomography (μCT) to study plant root systems has become routine, but is often hampered by poor contrast between roots, soil, soil water, and soil organic matter. In clinical radiology, imaging of poorly contrasting regions is frequently aided by the use of radio-opaque contrast media. In this study, we present evidence for the utility of iodinated contrast media (ICM) in the study of plant root systems using μCT. Different dilutions of an ionic and nonionic ICM (Gastrografin 370 and Niopam 300) were perfused into the aerial vasculature of juvenile pea plants via a leaf flap (Pisum sativum). The root systems were imaged via μCT, and a variety of image-processing approaches used to quantify and compare the magnitude of the contrast enhancement between different regions. Though the treatment did not appear to significantly aid extraction of full root system architectures from the surrounding soil, it did allow the xylem and phloem units of seminal roots and the vascular morphology within rhizobial nodules to be clearly visualized. The nonionic, low-osmolality contrast agent Niopam appeared to be well tolerated by the plant, whereas Gastrografin showed evidence of toxicity. In summary, the use of iodine-based contrast media allows usually poorly contrasting root structures to be visualized nondestructively using X-ray μCT. In particular, the vascular structures of roots and rhizobial nodules can be clearly visualized in situ.

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On the evaluation of methods for the recovery of plant root systems from X-ray computed tomography images

Functional Plant Biology ◽

10.1071/fp14071 ◽

2015 ◽

Vol 42 (5) ◽

pp. 460 ◽

Cited By ~ 12

Author(s):

Stefan Mairhofer ◽

Craig Sturrock ◽

Darren M. Wells ◽

Malcolm J. Bennett ◽

Sacha J. Mooney ◽

...

Keyword(s):

Computed Tomography ◽

Plant Root ◽

Ground Truth ◽

Real Data ◽

Root Systems ◽

Ground Truth Data ◽

X Ray ◽

Computed Tomography Images ◽

X Ray Computed ◽

Plant Root Systems

X-ray microcomputed tomography (μCT) allows nondestructive visualisation of plant root systems within their soil environment and thus offers an alternative to the commonly used destructive methodologies for the examination of plant roots and their interaction with the surrounding soil. Various methods for the recovery of root system information from X-ray computed tomography (CT) image data have been presented in the literature. Detailed, ideally quantitative, evaluation is essential, in order to determine the accuracy and limitations of the proposed methods, and to allow potential users to make informed choices among them. This, however, is a complicated task. Three-dimensional ground truth data are expensive to produce and the complexity of X-ray CT data means that manually generated ground truth may not be definitive. Similarly, artificially generated data are not entirely representative of real samples. The aims of this work are to raise awareness of the evaluation problem and to propose experimental approaches that allow the performance of root extraction methods to be assessed, ultimately improving the techniques available. To illustrate the issues, tests are conducted using both artificially generated images and real data samples.

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Developing a system for in vivo imaging of maize roots containing iodinated contrast media in soil using synchrotron XCT and XRF

Plant and Soil ◽

10.1007/s11104-020-04784-x ◽

2020 ◽

Author(s):

Callum P. Scotson ◽

Arjen van Veelen ◽

Katherine A. Williams ◽

Nicolai Koebernick ◽

Dan McKay Fletcher ◽

...

Keyword(s):

Computed Tomography ◽

Fluid Flow ◽

Contrast Media ◽

Plant Roots ◽

Iodinated Contrast Media ◽

Anatomical Features ◽

X Ray ◽

Iodinated Contrast ◽

X Ray Computed

Abstract Aims We sought to develop a novel experimental system which enabled application of iodinated contrast media to in vivo plant roots intact in soil and was compatible with time-resolved synchrotron X-ray computed tomography imaging. The system was developed to overcome issues of low contrast to noise within X-ray computed tomography images of plant roots and soil environments, the latter of which can complicate image processing and result in the loss of anatomical information. Methods To demonstrate the efficacy of the system we employ the novel use of both synchrotron X-ray computed tomography and synchrotron X-ray fluorescence mapping to capture the translocation of the contrast media through root vasculature into the leaves. Results With the application of contrast media we identify fluid flow in root vasculature and visualise anatomical features, which are otherwise often only observable in ex vivo microscopy, including: the xylem, metaxylem, pith, fibres in aerenchyma and leaf venation. We are also able to observe interactions between aerenchyma cross sectional area and solute transport in the root vasculature with depth. Conclusions Our novel system was capable of successfully delivering sufficient contrast media into root and leaf tissues such that anatomical features could be visualised and internal fluid transport observed. We propose that our system could be used in future to study internal plant transport mechanisms and parameterise models for fluid flow in plants.

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X‐Ray Computed Tomography of Crop Plant Root Systems Grown in Soil

Current Protocols in Plant Biology ◽

10.1002/cppb.20049 ◽

2017 ◽

Vol 2 (4) ◽

pp. 270-286 ◽

Cited By ~ 11

Author(s):

Stefan Mairhofer ◽

Tony Pridmore ◽

James Johnson ◽

Darren M. Wells ◽

Malcolm J. Bennett ◽

...

Keyword(s):

Computed Tomography ◽

Plant Root ◽

Root Systems ◽

Crop Plant ◽

X Ray ◽

X Ray Computed ◽

Plant Root Systems

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Improving Visualisation of In-Vivo Root Anatomy and Fluid Transport in Soil Using Iodinated Contrast in Synchrotron XCT and XRF

10.5194/egusphere-egu2020-8718 ◽

2020 ◽

Author(s):

Callum Scotson ◽

Katherine Williams ◽

Daniel McKay Fletcher ◽

Nicolai Koebernick ◽

Arjen van Veelen ◽

...

Keyword(s):

Contrast Media ◽

Fluid Transport ◽

Primary Root ◽

Root Anatomy ◽

Iodinated Contrast Media ◽

Time Resolved ◽

X Ray ◽

Iodinated Contrast ◽

Non Destructive

<p>Synchrotron X-ray computed tomography (SRXCT) imaging is a technique now commonly deployed for non-destructive 3D visualisation of root morphology in soil environments. However, visualising the internal anatomy of roots in soil using SRXCT can be difficult since the energy required for sufficient X-ray transmission through soil often results in poor contrast between root tissues. This reduces the amount of obtainable information about root anatomy and the effects of the soil environment on plant root internal structure. Contrast media is often used in SRXCT imaging to increase the contrast between tissues, enabling greater ease of both visualisation and image processing for internal structures of biological material.</p><p>In this work, we demonstrate that by introducing root material exposed to iodinated contrast media we can overcome these limitations and visualise internal root anatomy of in vivo roots intact within soil. To achieve this, we undertook time-resolved SRXCT imaging of juvenile maize plants growing in a specially designed growth system over a period of 24 hours. This system was designed such that only the base of the primary root would be suspended into iodinated contrast media whilst the rest of the root system remained in soil partially saturated with water, and the plant remained intact and alive. This enabled the basal section of primary root to take up iodinated contrast media without dispersal of the contrast media into the soil. Following the time-resolved imaging of the root system, leaf and stem material were then imaged using SRXCT and mapped using synchrotron X-ray florescence (SRXRF). Using this system, we were able to visualise and segment anatomical root features that are otherwise difficult to capture in vivo in soil using non-destructive 3D imaging such as vascular bundles (including phloem, xylem and proto-xylem) and structures within the cortex. We also gained inferences into fluid flow and transport within in vivo roots in soil based on this technique. The SRXCT imaging as well as the SRXRF mapping of stem and leaf material confirmed transport of the iodinated contrast media through plant vasculature and the distribution into leaf venation. This investigation demonstrates the quantity of data on internal root anatomy and fluid transport for in-vivo roots in soil that could be yielded from SRXCT and SRXRF in future.</p>

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Visual tracking for the recovery of multiple interacting plant root systems from X-ray $$\upmu $$ μ CT images

Machine Vision and Applications ◽

10.1007/s00138-015-0733-7 ◽

2015 ◽

Vol 27 (5) ◽

pp. 721-734 ◽

Cited By ~ 6

Author(s):

Stefan Mairhofer ◽

James Johnson ◽

Craig J. Sturrock ◽

Malcolm J. Bennett ◽

Sacha J. Mooney ◽

...

Keyword(s):

Visual Tracking ◽

Plant Root ◽

Root Systems ◽

Ct Images ◽

X Ray ◽

Plant Root Systems

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Arbuscular mycorrhizal modifications to plant root systems: scale, mechanisms and consequences

Mycorrhizal Technology in Agriculture ◽

10.1007/978-3-0348-8117-3_6 ◽

2002 ◽

pp. 71-85 ◽

Cited By ~ 45

Author(s):

G. Berta ◽

A. Fusconi ◽

J. E. Hooker

Keyword(s):

Plant Root ◽

Arbuscular Mycorrhizal ◽

Root Systems ◽

Plant Root Systems

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T cell mediated hypersensitivity to previously tolerated iodinated contrast media precipitated by introduction of atezolizumab

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-002521 ◽

2021 ◽

Vol 9 (5) ◽

pp. e002521

Author(s):

Sean Hammond ◽

Anna Olsson-Brown ◽

Joshua Gardner ◽

Paul Thomson ◽

Serat-E Ali ◽

...

Keyword(s):

Contrast Media ◽

Adverse Reactions ◽

Stevens Johnson Syndrome ◽

Iodinated Contrast ◽

Immune Mediated ◽

Johnson Syndrome ◽

Healthy Donors ◽

Concomitant Medications

Many adverse reactions associated with immune checkpoint inhibitor (ICI) treatments are immunologically driven and may necessitate discontinuation of the ICI. Herein, we present a patient who had been administered the radio contrast media amidotrizoate multiple times without issue but who then developed a Stevens-Johnson syndrome reaction after coadministration of atezolizumab. Causality was confirmed by a positive re-challenge with amidotrizoate and laboratory investigations that implicated T cells. Importantly, the introduction of atezolizumab appears to have altered the immunologic response to amidotrizoate in terms of the tolerance–elicitation continuum. Proof of concept studies demonstrated enhancement of recall responses to a surrogate antigen panel following in-vitro (healthy donors) and in-vivo (ICI patients) administrations of ICIs. Our findings highlight the importance of considering all concomitant medications in patients on ICIs who develop immune-mediated adverse reactions. In the event of some immune-related adverse reactions, it may be critical to identify the culprit antigen-forming entity that the ICIs have altered the perception of rather than simply attribute causality to the ICI itself in order to optimize both patient safety and treatment of malignancies.

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PEG modified BaGdF5:Yb/Er nanoprobes for multi-modal upconversion fluorescent, in vivo X-ray computed tomography and biomagnetic imaging

Biomaterials ◽

10.1016/j.biomaterials.2012.09.019 ◽

2012 ◽

Vol 33 (36) ◽

pp. 9232-9238 ◽

Cited By ~ 199

Author(s):

Songjun Zeng ◽

Ming-Kiu Tsang ◽

Chi-Fai Chan ◽

Ka-Leung Wong ◽

Jianhua Hao

Keyword(s):

Computed Tomography ◽

X Ray ◽

X Ray Computed ◽

Biomagnetic Imaging

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A study on the imaging characteristics of Gold nanoparticles as a contrast agent in X-ray computed tomography

Polish Journal of Medical Physics and Engineering ◽

10.1515/pjmpe-2017-0003 ◽

2017 ◽

Vol 23 (1) ◽

pp. 9-14 ◽

Cited By ~ 4

Author(s):

Asghar Mesbahi ◽

Fatemeh Famouri ◽

Mohammad Johari Ahar ◽

Maryam Olade Ghaffari ◽

Seyed Mostafa Ghavami

Keyword(s):

Computed Tomography ◽

Contrast Media ◽

Contrast Agent ◽

Hounsfield Unit ◽

Ct Number ◽

Agent Based ◽

X Ray ◽

Imaging Characteristics ◽

Tube Potential ◽

X Ray Computed

AbstractAim: In the current study, some imaging characteristics of AuNPs were quantitatively analyzed and compared with two conventional contrast media (CM) including Iodine and Gadolinium by using of a cylindrical phantom.Methods: AuNPs were synthesized with the mean diameter of 16 nm and were equalized to the concentration of 0.5, 1, 2 and 4 mg/mL in the same volumes. A cylindrical phantom resembling the head and neck was fabricated and drilled to contain small tubes filled with Iodine, Gadolinium, and AuNPs as contrast media. The phantom was scanned in different exposure techniques and CT numbers of three studied contrast media inside test tubes were measured in terms of Hounsfield Unit (HU). The imaging parameters of the noise and contrast to noise ratios (CNR) were calculated for all studied CMs.Results: AuNPs showed 128% and 166% higher CT number in comparison with Iodine and Gadolinium respectively. Also, Iodine had a greater CT number than Gadolinium for the same exposure techniques and concentration. The maximum CT number for AuNPs and studied contrast materials was obtained at the highest mAs and the lowest tube potential. The maximum CT number were 1033±11 (HU) for AuNP, 565±10 (HU) for Iodine, 458±11 for Gadolinium. Moreover, the maximum CNRs of 433±117, 203±53, 145±37 were found for AuNPs, Iodine and Gadolinium respectively.Conclusion: The contrast agent based on AuNPs showed higher imaging quality in terms of contrast and noise relative to other iodine and gadolinium based contrast media in X-ray computed tomography. Application of the AuNPs as a contrast medium in x-ray CT is recommended.

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