Magnetic resonance imaging of wood

1986 ◽  
Vol 16 (2) ◽  
pp. 423-426 ◽  
Author(s):  
Laurance D. Hall ◽  
Vasanthan Rajanayagam ◽  
Wendy A. Stewart ◽  
Paul R. Steiner
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Structural Features ◽  
Annual Growth ◽  
Resonance Imaging ◽  
Growth Rings ◽  
Magnetic Resonance Scanner ◽  
Annual Growth Rings ◽  
Do So

A magnetic resonance scanner has been used to obtain images at 0.14 T, based on the water in aspen (Populustremuloides Michx.). In addition to visualization of the expected structural features such as annual growth-rings and knots, several additional features appear that require further study. Kiln-dried wood does not contain sufficient water to give an image, but can do so after impregnation with water.

Cholesteatoma imaging using modified echo-planar diffusion-weighted magnetic resonance imaging

2010 ◽  
Vol 125 (1) ◽  
pp. 10-12 ◽  
Author(s):  
E Flook ◽  
S Izzat ◽  
A Ismail
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Magnetic Resonance Scanner ◽  
Primary Surgery ◽  
Diffusion Weighted ◽  
Imaging Results ◽  
Weighted Magnetic Resonance Imaging ◽  
Operative Findings ◽  
Echo Planar

AbstractIntroduction:Imaging of cholesteatomas can be useful especially in cases of recurrent disease. Computed tomography scans have been recommended before primary surgery, but cholesteatoma tissue looks similar to inflammatory tissue. Diffusion-weighted magnetic resonance imaging is both sensitive and specific in detecting cholesteatoma, which appears as a bright signal on a dark background. Non-echo-planar diffusion-weighted magnetic resonance imaging is superior to routine echo-planar diffusion-weighted magnetic resonance imaging as it minimises susceptibility artefacts; however, the addition of this facility involves expensive magnetic resonance scanner upgrading.Method:To avoid the cost of such upgrading, we modified our echo-planar diffusion-weighted magnetic resonance imaging parameters and then scanned 15 consecutive cases of suspected cholesteatoma or suspected recurrent cholesteatoma.Results:Imaging results correlated well with clinical and/or operative findings.Conclusion:These results indicate that software adjustments can enable echo-planar diffusion-weighted magnetic resonance imaging to detect cholesteatomas reliably, and as effectively as non-echo-planar diffusion-weighted magnetic resonance imaging. This discovery has the potential to facilitate reliable delayed post-operative screening of canal wall up mastoidectomies, avoiding the need for a ‘second look’ procedure.

Detection of hiddon morphology of wood by magnetic resonance imaging

1986 ◽  
Vol 16 (3) ◽  
pp. 684-687 ◽  
Author(s):  
Laurance D. Hall ◽  
Vasanthan Rajanayagam ◽  
Wendy A. Stewart ◽  
Paul R. Steiner ◽  
Suezone Chow
Keyword(s):  
Magnetic Resonance Imaging ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Imaging Technique ◽  
Nuclear Magnetic Resonance Imaging ◽  
Whole Body ◽  
Resonance Imaging ◽  
Magnetic Resonance Scanner ◽  
Magnetic Resonance Imaging Technique ◽  
Nuclear Magnetic

Hidden knots and regions of decay in aspen (Populustremuloides Michx.) sample are highlighted using the nuclear magnetic resonance imaging technique. The images were obtained on a whole-body nuclear magnetic resonance scanner that operates at 0.14 T for protons. The water in different regions of the sample responds differently, thereby imparting this useful information.

Magnetic resonance imaging of water movement through asparagus

2003 ◽  
Vol 30 (11) ◽  
pp. 1089 ◽  
Author(s):  
Julian A. Heyes ◽  
Christopher J. Clark
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Movement ◽  
Lateral Diffusion ◽  
Structural Features ◽  
Invasive Technique ◽  
Vascular Bundles ◽  
Lateral Movement ◽  
Resonance Imaging ◽  
Apoplastic Barrier

Asparagus spears are rapidly growing structures supplied with abundant vascular bundles. After extended periods of water loss, the stem surface becomes flaccid over a core of turgid tissue. We have used magnetic resonance imaging (MRI) coupled with a paramagnetic contrast reagent (Mn2+) to visualise water and ion movement within spear tissues. Using this technique we estimated the rate of water flow in the xylem and lateral movement out of the xylem into the surrounding tissues. Longitudinal flow rates of at least 3.7 mm min–1 and lateral diffusion rates of at least 17 μm min–1 were recorded. The outer parenchyma was difficult to label with vascular-supplied Mn2+, suggesting the presence of an apoplastic barrier. Stem shrinkage was greater in the outer parenchyma than in the inner cortex and pith parenchyma. Feeding the cut spear with 70 mM sucrose reduced the rate of lateral movement of Mn2+. The MRI technique highlighted differences in transport rates between adjacent vascular bundles and identified structural features with a resolution of 78 μm. This non-invasive technique is useful both for observing details of the transport paths in living tissue and for setting minimal estimates of transport rates.

Magnetic Resonance Imaging in Hand Osteoarthritis: Intraobserver Reliability and Criterion Validity for Clinical and Structural Characteristics

2015 ◽  
Vol 42 (7) ◽  
pp. 1224-1230 ◽  
Author(s):  
Marion C. Kortekaas ◽  
Wing-Yee Kwok ◽  
Monique Reijnierse ◽  
Ron Wolterbeek ◽  
Pernille Bøyesen ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Structural Characteristics ◽  
Structural Features ◽  
Criterion Validity ◽  
Intraobserver Reliability ◽  
Hand Osteoarthritis ◽  
Resonance Imaging ◽  
Scoring Method ◽  
Mri Features

Objective.To investigate criterion validity and intraobserver reliability of magnetic resonance imaging (MRI) in hand osteoarthritis (HOA).Methods.In 16 patients with HOA (median age 57 yrs, 62% women, 13 with erosive OA), 3 Tesla MRI scans with gadolinium-chelate administration of right second to fifth distal interphalangeal/proximal interphalangeal joints were scored according to the Oslo HOA scoring method for synovial thickening, bone marrow lesions (BML), osteophytes, joint space narrowing (JSN), and erosions (grade 0–3). Ultrasound (US) was scored for synovial thickening and osteophytes, radiographs for osteophytes and JSN (Osteoarthritis Research Society International score), and anatomical phases (Verbruggen-Veys score). Pain was assessed during physical examination. Correlations of MRI with US and radiographic features were assessed with generalizability theory. With generalized estimating equations analyses, MRI features were associated with pain, adjusting for confounding.Results.Forty-three percent, 27%, 77%, and 61% of joints had synovial thickening (moderate/severe), BML, osteophytes, and erosions on MRI, respectively. Intraobserver reliability, assessed in 6 patients, was good (ICC 0.77–1.00). Correlations between osteophytes, JSN, and erosions on radiographs and MRI were moderate, substantial, and fair (ICC 0.53, 0.68, and 0.32, respectively); MRI showed more lesions than radiography. Correlation between synovial thickening and osteophytes on MRI and US was moderate (ICC 0.43 and 0.49, respectively). MRI was more sensitive for synovial thickening, US for osteophytes. Pain was associated with moderate/severe synovial thickening (adjusted OR 2.4, 95% CI 1.06–5.5), collateral ligaments (4.2, 2.2–8.3), BML (3.5, 1.6–7.7), erosions (4.5, 1.7–12.2), and osteophytes (2.4, 1.1–5.2).Conclusion.MRI is a reliable and valid method to assess inflammatory and structural features in HOA. It gives additional information over radiographs and US.

scholarly journals Baseline Structural and Functional Magnetic Resonance Imaging Predicts Early Treatment Response in Schizophrenia with Radiomics Strategy

2020 ◽  
Author(s):  
Long-Biao Cui ◽  
Yu-Fei Fu ◽  
Lin Liu ◽  
Yongbin Wei ◽  
Xu-Sha Wu ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Functional Magnetic Resonance Imaging ◽  
Early Treatment ◽  
Prediction Models ◽  
Structural Features ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Early Treatment Response ◽  
Functional Features

Multimodal neuroimaging features might enable accurate classification and provide personalized treatment options in psychiatric domain. We conducted a retrospective study to investigate whether structural and functional features for predicting response to overall treatment of schizophrenia at the end of the first or a single hospitalization and in addition cross validate the results. This structural and functional magnetic resonance imaging (MRI) study included 85 and 63 patients with schizophrenia at baseline in dataset 1 and 2, respectively. After treatment, patients were classified as responders and non-responders. Features of gray matter and functional connectivity were extracted. Radiomics analysis was used to explore the predictive performance. Prediction models were based on structural features, functional features, and combined features. We found that the prediction accuracy was 80.38% (sensitivity: 87.28%; specificity 82.47%) for the model using functional features, and 69.68% (sensitivity: 83.96%; specificity: 72.41%) for the model using structural features. Our model combined both structural and functional features accurately predicted 92.04% responder and 80.23% non-responders to overall treatment, with an accuracy of 85.03%. These results highlight the power of structural and functional MRI-derived radiomics features to predict early response to treatment in schizophrenia. Prediction models of the very early treatment response in schizophrenia could augment effective therapeutic strategies.

Sign in / Sign up

Export Citation Format

Share Document