scholarly journals Correlative Magnetic Resonance Imaging and Histopathology in Small Ruminant Listeria Rhombencephalitis

2020 ◽  
Vol 11 ◽  
Author(s):  
Christina Precht ◽  
Peter Vermathen ◽  
Diana Henke ◽  
Anne Staudacher ◽  
Josiane Lauper ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Contrast Enhancement ◽  
Signal Intensity ◽  
Small Ruminants ◽  
Large Animal ◽  
Resonance Imaging ◽  
Post Contrast ◽  
Mri Features ◽  
Inflammatory Infiltrates

Background: Listeria rhombencephalitis, infection of the brainstem with Listeria monocytogenes, occurs mainly in humans and farmed ruminants and is associated with high fatality rates. Small ruminants (goats and sheep) are a large animal model due to neuropathological similarities. The purpose of this study was to define magnetic resonance imaging (MRI) features of listeria rhombencephalitis in naturally infected small ruminants and correlate them with histopathology. Secondly, the purpose of this study was to compare the results with MRI findings reported in humans.Methods: Twenty small ruminants (13 sheep and 7 goats) with listeria rhombencephalitis were prospectively enrolled and underwent in vivo MRI of the brain, including T2-weighted, fluid attenuation inversion recovery, and T1-weighted sequences pre- and post-contrast administration and postmortem histopathology. In MRI, lesions were characterized by location, extent, border definition, signal intensity, and contrast enhancement. In histopathology, the location, cell type, severity, and chronicity of inflammatory infiltrates and signs of vascular damage were recorded. In addition, histopathologic slides were matched to MRIs, and histopathologic and MRI features were compared.Results: Asymmetric T2-hyperintense lesions in the brainstem were observed in all animals and corresponded to the location and pattern of inflammatory infiltrates in histopathology. Contrast enhancement in the brainstem was observed in 10 animals and was associated with vessel wall damage and perivascular fibrin accumulation in 8 of 10 animals. MRI underestimated the extension into rostral brain parts and the involvement of trigeminal ganglia and meninges.Conclusion: Asymmetric T2-hyperintense lesions in the brainstem with or without contrast enhancement can be established as criteria for the diagnosis of listeria rhombencephalitis in small ruminants. Brainstem lesions were similar to human listeria rhombencephalitis in terms of signal intensity and location. Different from humans, contrast enhancement was a rare finding, and abscessation was not observed.

Lipoma in olecranon bursa: A case report

2021 ◽  
Vol 3 ◽  
pp. 67-69
Author(s):  
Shalini Agarwal ◽  
Jyoti Siwach ◽  
Ramneet Wadi ◽  
Nipun Gupta
Keyword(s):  
Magnetic Resonance Imaging ◽  
Case Report ◽  
Magnetic Resonance ◽  
Contrast Enhancement ◽  
Local Anesthesia ◽  
Signal Intensity ◽  
Ultrasound Examination ◽  
Fat Cells ◽  
Resonance Imaging ◽  
Diffusion Weighted Images

We report a case of a 55-year-old male patient who presented with swelling over his right elbow of 5-year duration. An ultrasound examination revealed an echogenic mass within the olecranon bursa. On magnetic resonance imaging, the mass revealed the signal intensity of fat, and it was attached to the bursal lining by means of a pedicle. There was no restriction on diffusion-weighted images and no significant contrast enhancement. Excision was performed under local anesthesia. The excised specimen revealed mature fat cells on histopathology.

Contrast magnetic resonance imaging for measurement of cartilage glycosaminoglycan content in dogs: A pilot study

2013 ◽  
Vol 26 (02) ◽  
pp. 100-104 ◽  
Author(s):  
M. C. Stewart ◽  
L. Ciobanu ◽  
P. D. Constable ◽  
J. F. Naughton
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Coefficient Of Variation ◽  
Signal Intensity ◽  
Linear Regression Analysis ◽  
Resonance Imaging ◽  
Post Contrast ◽  
Enhanced Mri ◽  
Over Time

SummaryObjective: To assess the ability of a contrast-enhanced magnetic resonance imaging (MRI) technique to quantitatively determine glycosaminoglycan content in canine articular cartilage.Methods: Fifty-four full-thickness cartilage discs were collected from the femorotibial and scapulohumeral joints of three adult dogs immediately following euthanasia. One set of discs from each dog was analysed for glycosaminoglycan content using a colourimetric laboratory assay. The remaining position-matched set of discs from contralateral limbs underwent pre- and post-contrast gadolinium-enhanced MRI, using repeated saturation recovery pulse sequences which were used to generate calculated T1 maps of the cartilage discs. Linear regression analysis was then performed relating delayed gadolinium-enhanced MRI T1 calculated signal intensity to the cartilage glycosaminoglycan content normalized to DNA content. Repeatability of triplicate measurements was estimated by calculating the coefficient of variation.Results: Mean coefficient of variation estimates for the gadolinium-enhanced MRI T1 signal intensity values for nine sampling sites from three dogs ranged from 5.9% to 7.5%. Gadolinium-enhanced MRI T1 signal intensity was significantly correlated (p <0.05) with normalized glycosaminoglycan content in two dogs (r = 0.79, p = 0.011; r = 0.78, p = 0.048), but not in the third dog (r = 0.53, p = 0.071).Clinical significance: Gadolinium-enhanced MRI assessment of cartilage may be predictive of glycosaminoglycan content and therefore offer an in vivo assessment of changes in cartilage characteristics over time. Additional studies appear indicated to determine the reliability and clinical applicability of gadolinium-enhanced MRI in detecting changes in cartilage over time.

scholarly journals Detection of pancreatic fibrosis using magnetic resonance imaging: correlation with histopathology

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Carsyn Kranz ◽  
Omer Saeed ◽  
Vitalis Osuji ◽  
Evan Fogel ◽  
Nicholas Zyromski ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Signal Intensity ◽  
Interobserver Agreement ◽  
Weighted Kappa ◽  
Pancreatic Fibrosis ◽  
Imaging Biomarkers ◽  
Fibrosis Score ◽  
Resonance Imaging ◽  
Post Contrast

Background and Hypothesis: Diagnosis of chronic pancreatitis (CP) is challenging and controversial. Magnetic Resonance Imaging (MRI) offers a noninvasive modality to diagnose CP, but its findings have been rarely correlated with histopathology. We aimed to assess the correlation of T1 signal intensity ratio of pancreas to spleen (T1 SIRp/s) and arterio-venous ratio (AVR) of the parenchyma on MRI and Cambridge score on MRCP with surgical histopathology in patients who underwent pancreatic resection.  Methods: We identified 160 pancreatic resections performed in adults between 2017 and 2019 by searching our institution’s surgery database. Seventy-one of them had surgical pathology specimens available and 59 of them had MRI/MRCP within 3 months prior to the surgery. Histologic grading was performed by a gastrointestinal pathologist using Ammann’s fibrosis score. Two image analysts blinded to the clinical information and fibrosis score measured T1 SIRp/s from unenhanced T1-weighted fat-saturated gradient-echo images and arterio-venous ratio (AVR) from post-contrast dynamic phase. Cambridge score was also recorded from MRCP. Statistical analysis included Pearson’s correlation coefficient of the T1 SIRp/s, AVR, and Cambridge score with the fibrosis score and weighted kappa for interobserver agreement.  Results: Correlations between T1 SIRp/s and AVR with the fibrosis score were (r= -0.30, p=0.02, 95%CI: -0.51 to -0.04 and r= -0.36, p=0.01, 95%CI: -0.58 to -0.09, respectively). In comparison, there is less correlation between the Cambridge grade and the fibrosis (r= 0.17, p=0.15, 95% CI for r= -0.07 to 0.39). Interobserver agreement was good (kappa=0.80).  Conclusion: There is moderate correlation between the T1 signal intensity and enhancement ratio of the pancreas with pancreatic fibrosis. This is higher than the correlation between the Cambridge grade and fibrosis. Multi-institutional, prospective studies are needed to verify T1 SIR and AVR as potential imaging biomarkers of pancreatic fibrosis. 

scholarly journals 1.5 Tesla Magnetic Resonance Imaging Features of Canine Intracranial Intra-axial Hematomas

2021 ◽  
Vol 8 ◽  
Author(s):  
James Whitlock ◽  
Andrew Holdsworth ◽  
Carles Morales ◽  
Laurent Garosi ◽  
Inés Carrera
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Contrast Enhancement ◽  
Clinical Signs ◽  
Border Region ◽  
Imaging Features ◽  
Resonance Imaging ◽  
Mri Findings ◽  
Mri Features ◽  
Mri Study

The differentiation of solitary intra-axial hematomas from hemorrhagic neoplasms based on their magnetic resonance imaging (MRI) features is challenging. The treatment and prognosis for these two disease entities are vastly different and distinction between them is often based on MRI findings alone. The aim of this study was to describe the 1.5 tesla MRI features of canine intra-axial hematomas and correlate these findings with the evolution of hemorrhages described in human brains. Retrospective evaluation of patient details, clinical signs, and MRI findings of dogs with intra-axial hematomas that were histopathologically confirmed or determined via repeat MRI study and/or resolution of neurological signs. Ten dogs met the inclusion criteria. All 10 hematoma lesions were determined to be 2–7 days in age. On MRI, all 10 hemorrhagic lesions were comprised of two distinct regions; a relatively thin T1-weighted (T1W), T2-weighted (T2W) and gradient echo (GRE) hypointense (9/10) peripheral border region and a large central region that was heterogenous but predominantly T1W, T2W and GRE hyperintense (8/10). The peripheral border region was complete in its integrity in all 10 cases on T2W and GRE sequences. Contrast enhancement was present in (6/10) hematoma lesions and was always peripheral in nature with no evidence of central enhancement associated with any of the lesions. An intra-axial hematoma should be suspected in solitary hemorrhagic space occupying lesions that have a complete hypointense peripheral rim, elicit a peripheral contrast enhancement pattern, and display the expected temporal pattern of hematoma evolution.

Uterine fibroid embolization can still be improved: observations on post-procedure magnetic resonance imaging

2005 ◽  
Vol 46 (5) ◽  
pp. 547-553 ◽  
Author(s):  
E. J. Dorenberg ◽  
Z. Novakovic ◽  
H.-J. Smith ◽  
G. Hafsahl ◽  
J. Å. Jakobsen
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Contrast Enhancement ◽  
Uterine Fibroid ◽  
Uterine Fibroids ◽  
Resonance Imaging ◽  
Post Contrast ◽  
Uterine Fibroid Embolization ◽  
Uterine Arteries ◽  
Uterine Volume

Purpose: To evaluate the efficacy and completeness of uterine fibroid embolization (UFE) measured by changes in volume and signal intensity at magnetic resonance imaging (MRI), and to compare with clinical outcome. Material and Methods: 40 women with symptomatic uterine fibroids underwent bilateral uterine artery embolization. At MRI studies, including post-contrast sequences before and repeatedly after treatment, the uterus and dominant fibroids were evaluated for volume, location, and contrast enhancement. Prior to treatment, all myomas showed significant contrast enhancement. The mean uterine volume was 929 ml. Clinical examinations with emphasis on menorrhagia, pelvic pain, and urinary dysfunction were performed before and 6 and 12 months after treatment. Results: UFE was bilaterally successful in 38 patients. After UFE, MRI showed no enhancement of myomas in 30 patients. In 8 patients, post-procedural MRI revealed partially remaining vascularization of fibroids despite angiographically complete embolization of the uterine arteries. On average, uterine volume decreased by 46.2% at 12 months. There was significant improvement of symptoms in the majority of patients, but slightly less improvement in patients with partially remaining vascularization of myomas. Conclusion: UFE causes significant volume reduction of myomas and clinical improvement. MRI can reveal remaining vascularization in myomas despite angiographically complete embolization of uterine arteries.

scholarly journals Cardiac magnetic resonance imaging of myocardial mass and fibrosis in primary aldosteronism

2018 ◽  
Vol 7 (3) ◽  
pp. 413-424 ◽  
Author(s):  
Marianne Aa Grytaas ◽  
Kjersti Sellevåg ◽  
Hrafnkell B Thordarson ◽  
Eystein S Husebye ◽  
Kristian Løvås ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Cardiac Magnetic Resonance ◽  
Magnetic Resonance ◽  
Contrast Enhancement ◽  
Primary Aldosteronism ◽  
T1 Mapping ◽  
Newly Diagnosed ◽  
Resonance Imaging ◽  
Post Contrast ◽  
Lv Mass

Background Primary aldosteronism (PA) is associated with increased cardiovascular morbidity, presumably due to left ventricular (LV) hypertrophy and fibrosis. However, the degree of fibrosis has not been extensively studied. Cardiac magnetic resonance imaging (CMR) contrast enhancement and novel sensitive T1 mapping to estimate increased extracellular volume (ECV) are available to measure the extent of fibrosis. Objectives To assess LV mass and fibrosis before and after treatment of PA using CMR with contrast enhancement and T1 mapping. Methods Fifteen patients with newly diagnosed PA (PA1) and 24 age- and sex-matched healthy subjects (HS) were studied by CMR with contrast enhancement. Repeated imaging with a new scanner with T1 mapping was performed in 14 of the PA1 and 20 of the HS median 18 months after specific PA treatment and in additional 16 newly diagnosed PA patients (PA2). Results PA1 had higher baseline LV mass index than HS (69 (53–91) vs 51 (40–72) g/m2; P < 0.001), which decreased significantly after treatment (58 (40–86) g/m2; P < 0.001 vs baseline), more with adrenalectomy (n = 8; −9 g/m2; P = 0.003) than with medical treatment (n = 6; −5 g/m2; P = 0.075). No baseline difference was found in contrast enhancement between PA1 and HS. T1 mapping showed no increase in ECV as a myocardial fibrosis marker in PA. Moreover, ECV was lower in the untreated PA2 than HS 10 min post-contrast, and in both PA groups compared with HS 20 min post-contrast. Conclusion Specific treatment rapidly reduced LV mass in PA. Increased myocardial fibrosis was not found and may not represent a common clinical problem.

scholarly journals CT and MRI features of Primary Orbital Lymphoma: review of 14 cases

2011 ◽  
Vol 1 (2) ◽  
pp. 87-90
Author(s):  
Chen Wang Jin ◽  
Netra Rana ◽  
Yuan Wang ◽  
ShaoHui Ma ◽  
Min Li ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Computed Tomography ◽  
Magnetic Resonance ◽  
Signal Intensity ◽  
Ct Imaging ◽  
Extraocular Muscles ◽  
Resonance Imaging ◽  
Mri Features ◽  
Orbital Lymphoma ◽  
Ct And Mri

Objective: To assess the computed tomography (CT) imaging and magnetic resonance imaging (MRI) features of primary orbital lymphoma and to establish a differential diagnosis. Material & Methods: Fourteen patients (9 male and 5 female) suffering from primary orbital lymphoma underwent CT scanning with and without contrast. Pre- and post-contrast MRI scans were performed in 10 patients. Their ages ranged from 1.5 to 65 years (average age: 36 years). The course of diseases varied from 2 months to 16 years. Results: The diagnosis was confirmed pathologically in all cases. Lesions were bilateral in 4 cases and unilateral in 10 cases. Periorbital preseptal tissues were involved mainly in the upper lateral quadrant of the orbit. Focal masses were observed in 5 patients. Lesions that infiltrated the lacrimal gland, adjacent extraocular muscles and intraorbital tissues, along with the extraocular muscles, were found in other patients. The tumors that had advanced into intraorbital tissues and had involved extraocular muscles, displayed either a 'casting sign' or a 'ring sign'. Isodense soft-tissue masses with clear demarcation were found on plain CT film and lesions displayed low to intermediate signal intensity on T1- weighted MRI and relatively low or high signal intensity on T2-weighted MRI. The lesions demonstrated homogeneously marked enhancement on CT and MRI with contrast medium. Conclusion: CT imaging and MRI - particularly MRI - can demonstrate the location, configuration, inner structure and characteristic manifestations of the orbital lymphomas. This may assist the pre-operative diagnosis of these lesions. Key Words: Orbital tumor; Lymphoma; Pseudotumor; Computed tomography; Magnetic resonance imaging DOI: 10.3126/ajms.v1i2.3401Asian Journal of Medical Sciences 1 (2010) 87-90

Magnetic resonance imaging changes following natalizumab discontinuation in multiple sclerosis patients with progressive multifocal leukoencephalopathy

2018 ◽  
Vol 24 (14) ◽  
pp. 1902-1908 ◽  
Author(s):  
Jérôme Hodel ◽  
Blanche Bapst ◽  
Olivier Outteryck ◽  
Sébastien Verclytte ◽  
Vincent Deramecourt ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Progressive Multifocal Leukoencephalopathy ◽  
Contrast Enhancement ◽  
Mass Effect ◽  
Resonance Imaging ◽  
Post Contrast ◽  
Fluid Attenuated Inversion Recovery ◽  
Multiple Sclerosis Patients ◽  
Mri Changes

Background: Detecting early progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome (PML-IRIS) is clinically relevant. Objective: Evaluating magnetic resonance imaging (MRI) changes following natalizumab (NTZ) discontinuation and preceding PML-IRIS. Methods: MRIs (including diffusion-weighted imaging (DWI), T2-weighted fluid-attenuated inversion recovery (T2-FLAIR), post-contrast T1-weighted sequences) were performed every week following PML diagnosis in 11 consecutive NTZ-PML patients. PML expansion, punctate lesions, contrast-enhancement, and mass-effect/edema were evaluated on each MRI sequence, following NTZ discontinuation. Results: PML-IRIS occurred from 26 to 89 days after NTZ discontinuation. MRI changes prior to early PML-IRIS appeared significantly more pronounced using DWI compared to T2-FLAIR imaging ( p < 0.003). Two DWI features (marked PML expansion, punctate lesions) systematically preceded contrast-enhancement. Conclusion: Subtle changes may occur on DWI preceding contrast-enhancement.

Influence of preoperative statins and aspirin administration on biological and magnetic resonance imaging properties in patients with abdominal aortic aneurysm

VASA ◽  
2020 ◽  
pp. 1-9
Author(s):  
Milos Sladojevic ◽  
Petar Zlatanovic ◽  
Zeljka Stanojevic ◽  
Igor Koncar ◽  
Sasenka Vidicevic ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Abdominal Aortic Aneurysm ◽  
Magnetic Resonance ◽  
Aortic Aneurysm ◽  
Signal Intensity ◽  
Psoas Muscle ◽  
Resonance Imaging ◽  
Maximal Diameter ◽  
Aneurysm Wall ◽  
Abdominal Aortic

Summary: Background: Main objective of this study was to evaluate the influence of statins and/or acetylsalicylic acid on biochemical characteristics of abdominal aortic aneurysm (AAA) wall and intraluminal thrombus (ILT). Patients and methods: Fifty patients with asymptomatic infrarenal AAA were analyzed using magnetic resonance imaging on T1w sequence. Relative ILT signal intensity (SI) was determined as a ratio between ILT and psoas muscle SI. Samples containing the full ILT thickness and aneurysm wall were harvested from the anterior surface at the level of the maximal diameter. The concentration of enzymes such as matrix metalloproteinase (MMP) 9, MMP2 and neutrophil elastase (NE/ELA) were analyzed in ILT and AAA wall; while collagen type III, elastin and proteoglycan 4 were analyzed in harvested AAA wall. Oxidative stress in the AAA wall was assessed by catalase and malondialdehyde activity in tissue samples. Results: Relative ILT signal intensity (1.09 ± 0.41 vs 0.89 ± 0.21, p = 0.013) were higher in non-statin than in statin group. Patients who were taking aspirin had lower relative ILT area (0.89 ± 0.19 vs 1.13. ± 0.44, p = 0.016), and lower relative ILT signal intensity (0.85 [0.73–1.07] vs 1.01 [0.84–1.19], p = 0.021) compared to non-aspirin group. There were higher concentrations of elastin in AAA wall among patients taking both of aspirin and statins (1.21 [0.77–3.02] vs 0.78 (0.49–1.05) ng/ml, p = 0.044) than in patients who did not take both of these drugs. Conclusions: Relative ILT SI was lower in patients taking statin and aspirin. Combination of antiplatelet therapy and statins was associated with higher elastin concentrations in AAA wall.

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