magnet resonance
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2021 ◽  
Vol 12 ◽  
Author(s):  
Stefan Macher ◽  
Ewald Unger ◽  
Martin Zalaudek ◽  
Michael Weber ◽  
Gottfried Kranz ◽  
...  

Introduction: Botulinumtoxin associated muscle denervation (BNTMD) can be detected by magnet resonance imaging (MRI), MRI may provide further insights into the exact timeline of BNTMD and the potential impact and timing of physical exercise. We aimed to assess the time interval until detection of BNTMD by MRI and whether immediate physical exercise after intramuscular BNT injection has a measurable effect on clinical parameters and the intramuscular denervation dynamics illustrated by MRI.Materials and Methods: Eleven age-matched patients were randomized to an “exercise” or “no-exercise” group. Eighty mouse-units of incobotulinumtoxin were injected into the spastic biceps muscle. MRI of the injected region, hand-held dynamometry of elbow flexor strength and clinical rating scales (mAS, CGI-I) were conducted in predefined intervals.Results: We could not detect BNTMD within 24 h but 7 days after injection independent of group allocation (exercise n = 6, no-exercise n = 5). Denervation signs were more diffuse and spread into adjacent muscles in patients having received exercise. We could not detect differences concerning clinical measures between the two groups.Conclusions: Physical exercise might influence BNTMD dynamics and promote propagation of T2-MR muscle denervation signs from the injected site into adjacent muscles.Trial registration:clinicaltrialsregister.eu, Identifier 2017-003117-25.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
C. Riemann ◽  
L. U. Scholtz ◽  
H. B. Gehl ◽  
M. Schürmann ◽  
H. Sudhoff ◽  
...  

AbstractThe estimation of scalar electrode position is a central point of quality control during the cochlear implant procedure. Ionic radiation is a disadvantage of commonly used radiologic estimation of electrode position. Recent developments in the field of cochlear implant magnets, implant receiver magnet position, and MRI sequence usage allow the postoperative evaluation of inner ear changes after cochlear implantation. The aim of the present study was to evaluate the position of lateral wall and modiolar cochlear implant electrodes using 3 T MRI scanning. In a prospective study, we evaluated 20 patients (10× Med-El Flex 28; 5× HFMS AB and 5× SlimJ AB) with a 3 T MRI and a T2 2D Drive MS sequence (voxel size: 0.3 × 0.3 × 0.9 mm) for the estimation of the intracochlear position of the cochlear implant electrode. In all cases, MRI allowed a determination of the electrode position in relation to the basilar membrane. This observation made the estimation of 19 scala tympani electrode positions and a single case of electrode translocation possible. 3 T MRI scanning allows the estimation of lateral wall and modiolar electrode intracochlear scalar positions.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jonathan Häußer ◽  
Juliane Wieber ◽  
Philip Catalá-Lehnen

Abstract Background Extracorporeal shock wave therapy (ESWT) has been used for various pathologies associated with bone marrow oedema (BME). However, it is still not clear whether ESWT may be favourable in the treatment of BME. Therefore, the aim of this systematic review was to assess the efficacy of ESWT for the treatment of BME. Methods MEDLINE was searched for relevant literature with no time constraints. Both randomized and non-randomized trials were included. Case reports and conference abstracts were excluded. Titles and abstracts were screened and full-text articles of included studies were retrieved. Data on the effect of ESWT on pain, function, and the BME area on magnet resonance imaging were extracted. Results Pain, function, and magnet resonance imaging results all improved across the studies — regardless of whether it was a randomized or non-randomized study. This effect was consistent across multiple pathologies such as osteonecrosis of the femoral head, BME associated with knee osteoarthritis, Kienböck’s disease, and osteitis pubis. The meta-analysis showed that pain (after 1 month: weighted mean difference (WMD) = − 2.23, 95% CI − 2.58 to − 1.88, P < 0.0001; after 3–6 month: WMD = − 1.72, 95% CI − 2.52 to − 0.92, P < 0.00001) and function (after 1 month: WMD = − 1.59, 95% CI − 2.04 to − 1.14, P < 0.0001; after 3–6 month: WMD = − 2.06, 95% CI − 3.16 to − 0.96, P = 0.0002; after ≥ 12 month: WMD = − 1.20, 95% CI − 1.83 to − 0.56, P = 0.0002) was reduced in terms of ESWT treatment compared to a control group. Conclusions Based on the available evidence, ESWT may be an adequate option for conservative therapy in pathologies involving BME. Trial registration PROSPERO, CRD42021201719. Registered 23 December 2020


PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249532
Author(s):  
Farid Ziayee ◽  
Tim Ullrich ◽  
Dirk Blondin ◽  
Hannes Irmer ◽  
Christian Arsov ◽  
...  

Dynamic contrast enhanced imaging (DCE) as an integral part of multiparametric prostate magnet resonance imaging (mpMRI) can be evaluated using qualitative, semi-quantitative, or quantitative assessment methods. Aim of this study is to analyze the clinical benefits of these evaluations of DCE regarding clinically significant prostate cancer (csPCa) detection and grading. 209 DCE data sets of 103 consecutive patients with mpMRI (T2, DWI, and DCE) and subsequent MRI-(in-bore)-biopsy were retrospectively analyzed. Qualitative DCE evaluation according to PI-RADS v2.1, semi-quantitative (curve type; DCE score according to PI-RADS v1), and quantitative Tofts analyses (Ktrans, kep, and ve) as well as PI-RADS v1 and v2.1 overall classification of 209 lesions (92 PCa, 117 benign lesions) were performed. Of each DCE assessment method, cancer detection, discrimination of csPCa, and localization were assessed and compared to histopathology findings. All DCE analyses (p<0.01–0.05), except ve (p = 0.02), showed significantly different results for PCa and benign lesions in the peripheral zone (PZ) with area under the curve (AUC) values of up to 0.92 for PI-RADS v2.1 overall classification. In the transition zone (TZ) only the qualitative DCE evalulation within PI-RADS (v1 and v2.1) could distinguish between PCa and benign lesions (p<0.01; AUC = 0.95). None of the DCE parameters could differentiate csPCa from non-significant (ns) PCa (p ≥ 0.1). Qualitative analysis of DCE within mpMRI according to PI-RADS version 2.1 showed excellent results regarding (cs)PCa detection. Semi-quantitative and quantitative parameters provided no additional improvements. DCE alone wasn’t able to discriminate csPCa from nsPCa.


2021 ◽  
Author(s):  
CHAO MENG ◽  
Jia-wei Wang ◽  
Lei Liu ◽  
Wen-jing Wei ◽  
Jian-hua Tao ◽  
...  

Abstract ObjectiveTo shed light on the clinical characteristics, magnet resonance imaging(MRI) changes, and prognosis of myelin oligodendrocyte glycoprotein antibody (MOG-IgG) positive OPN in Han Chinese.MethodsWe observed 39 MOG-IgG positive patients in our ward from January 1, 2017 , to December 31, 2019. Twenty patients met OPN inclusion criteria included contrast enhancement surrounding the optic nerve, and at least one of the following clinical symptoms: 1) reduction of visual acuity, 2) impairment of visual field, and 3) eye pain. Single course group(n=11) and recurrence group(n=9) were used for comparison. Outcome variables included Wingerchuk visual acuity classification.Results Of the 20 patients with MOG-IgG positive OPN, 12(60%) were women. Ten cases (50%) presented with bilateral and 17 eyes (56.67%) with severe visual loss (SVL,≤ 0.1). Twenty-one(70.00%) eyes showed edema of optic disc. Twenty-five eyes (83.3%) had longitudinally extensive perineural enhancement. At follow-up, 4 (13%) eyes still had SVL, while 26 (87%) eyes had no SVL, and of the 19 ON patients, 3 (9%) eyes still had SVL. Seven patients (35.00%) experienced at least a relapse(median interval 13.5 months ), and of the 19 ON cases, 4 (21%) patients experienced relapse. The relapse occurred more often in younger patients than the older (mean year: 38.00 vs. 45.54 years; P = 0.025). There were no optic chiasm and brainstem lesions.ConclusionsMOG-IgG positive OPN in Han Chinese often causes severe bilateral visual loss and longitudinally extensive perineural lesion. Younger patients are more likely to relapse. Optic chiasm and brainstem lesions were relatively rare.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Constantinos Zamboglou ◽  
Maria Kramer ◽  
Selina Kiefer ◽  
Peter Bronsert ◽  
Lara Ceci ◽  
...  

AbstractComparison studies using histopathology as standard of reference enable a validation of the diagnostic performance of imaging methods. This study analysed (1) the impact of different image-histopathology co-registration pathways, (2) the impact of the applied data analysis method and (3) intraindividually compared multiparametric magnet resonance tomography (mpMRI) and prostate specific membrane antigen positron emission tomography (PSMA-PET) by using the different approaches. Ten patients with primary PCa who underwent mpMRI and [18F]PSMA-1007 PET/CT followed by prostatectomy were prospectively enrolled. We demonstrate that the choice of the intermediate registration step [(1) via ex-vivo CT or (2) mpMRI] does not significantly affect the performance of the registration framework. Comparison of analysis methods revealed that methods using high spatial resolutions e.g. quadrant-based slice-by-slice analysis are beneficial for a differentiated analysis of performance, compared to methods with a lower resolution (segment-based analysis with 6 or 18 segments and lesions-based analysis). Furthermore, PSMA-PET outperformed mpMRI for intraprostatic PCa detection in terms of sensitivity (median %: 83–85 vs. 60–69, p < 0.04) with similar specificity (median %: 74–93.8 vs. 100) using both registration pathways. To conclude, the choice of an intermediate registration pathway does not significantly affect registration performance, analysis methods with high spatial resolution are preferable and PSMA-PET outperformed mpMRI in terms of sensitivity in our cohort.


2021 ◽  
Vol 11 (2) ◽  
pp. 202
Author(s):  
Friederike S. Bähr ◽  
Burkhard Gess ◽  
Madlaine Müller ◽  
Sandro Romanzetti ◽  
Michael Gadermayr ◽  
...  

With emerging treatment approaches, it is crucial to correctly diagnose and monitor hereditary and acquired polyneuropathies. This study aimed to assess the validity and accuracy of magnet resonance imaging (MRI)-based muscle volumetry.Using semi-automatic segmentations of upper- and lower leg muscles based on whole-body MRI and axial T1-weighted turbo spin-echo sequences, we compared and correlated muscle volumes, and clinical and neurophysiological parameters in demyelinating Charcot-Marie-Tooth disease (CMT) (n = 13), chronic inflammatory demyelinating polyneuropathy (CIDP) (n = 27), and other neuropathy (n = 17) patients.The muscle volumes of lower legs correlated with foot dorsiflexion strength (p < 0.0001), CMT Neuropathy Score 2 (p < 0.0001), early gait disorders (p = 0.0486), and in CIDP patients with tibial nerve conduction velocities (p = 0.0092). Lower (p = 0.0218) and upper (p = 0.0342) leg muscles were significantly larger in CIDP compared to CMT patients. At one-year follow-up (n = 15), leg muscle volumes showed no significant decrease.MRI muscle volumetry is a promising method to differentiate and characterize neuropathies in clinical practice.


Author(s):  
Karthikeyan K

Whereas the historical background of medical field started in 1895 with Roentgen Wilhelm participating in the first x-rays photograph and proceeded through 1913 with the discovery of mammogram and 1927 with first cerebellar echocardiogram, advanced medicine tomography came into focus in the 1950s with the discovery of PET and ultrasonic image processing. The first computed tomography (CT) scanners was created by Hounsfield Godfrey and CoreMark Allanin 1972, while the first commercialized Magnet Resonance Imaging (MRI) scanners were produced by Raymond Dalmatian in 1977. The creation of general methods and terminology of digitized signal and image processing occurred in tandem with the growth of medical imaging technology in the 1970s and beyond, as well as the advent of digital processors. In an examination of biological applications and analysis in the era of big data and deep learning, this article analyzes background and phraseology: Pattern Classification, Artificial Intelligence, Machine Learning, Big Data.


2021 ◽  
pp. 18-25
Author(s):  
A.Yu. Alekseeva ◽  
◽  
A.M. Ziganshin ◽  

Accurate calculation of the estimated fetal weight is necessary for the choice of a correct approach to management of labour. Th e existing methods are not universal and require complex application. Th is article presents a review of literatures published in PubMed and Google Scholar databases in 1955-2021 and devoted to historical aspects in development of the existing clinical and instrumental approaches to calculation of estimated fetal weight. The paper presents existing methods for calculation of estimated fetal weight at diff erent gestational ages as well as methods making it possible to predict fetal weight before gestation onset. Data on their informative value during the third trimester and alterations in their accuracy depending on the pregnant patient’s BMI are presented. Th e topic of application of magnet-resonance imaging for fetometry is considered with comparison of this approach to a more common method of ultrasonography.


2021 ◽  
Vol 5 ◽  
pp. 95-101
Author(s):  
A.G. Gavrilov ◽  
◽  
D.A. Odamanov ◽  
S.V. Shugai ◽  
F.D. Abdurakhimov ◽  
...  

Rosette-forming glioneuronal tumour (RGNT) is a rare primary tumour of the central nervous system with a low degree of malignancy. Using such databases as PubMed, Web of Science and Google Scholar as well as terms “rosette and forming and glioneuronal”, we found 153 RGNT cases dated 2002-2020. Low occurrence of the disease and absence of specific symptoms make it possible to perform a differential diagnosis judging from the clinical picture. Clinical manifestations of the disease are rather variable and depend on the tumour location. Magnet-resonance tomography is the leading method for diagnosis of such disease. The article presents a case of successful treatment of a patient RGNT of the fourth ventricle. Subtotal resection of the tumour was performed due to its diffuse growth. Tumour residue is subject to dynamic follow-up observation


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