Safety and Feasibility of Magnetic Resonance Imaging of the Brain at 1.5 Tesla in Patients with Temporary Transmyocardial Pacing Leads

2017 ◽  
Vol 67 (02) ◽  
pp. 086-091 ◽  
Author(s):  
Rami Homsi ◽  
Fritz Mellert ◽  
Roger Luechinger ◽  
Daniel Thomas ◽  
Jonas Doerner ◽  
...  

Background Temporary transmyocardial pacing leads (TTPLs) represent an absolute contraindication to magnetic resonance imaging (MRI). The purpose of this study was to evaluate the safety and feasibility of MRI at 1.5 Tesla (T) using a transmit/receive (T/R) head coil in patients with TTPL. Methods TTPLs (220 cm, Osypka TME, Dr. Osypka GmbH, Rheinfelden, Germany) were implanted in a phantom and exposed to conditions of a 1.5 T brain examination using a T/R head coil. Temperature changes at the lead tip were continuously recorded. A total of 28 patients with TTPL and an urgent indication for a brain MRI underwent MRI at 1.5 T with vital sign monitoring. A T/R head coil was used to minimize radiofrequency exposure of the TTPL. Before and immediately after the MRI scan, TTPL lead impedance, pacing capture threshold (PCT), signal slope, and sensing were measured. Serum troponin I was determined before and after MRI to detect thermal myocardial injury. Results In vitro, the maximum temperature increase from radiofrequency-induced heating of the TTPL tip was < 1°C. In vivo, no complications, such as heating sensations, dizziness, unexpected changes in heart rate or rhythm, or other unusual signs or symptoms were observed. No significant changes in the lead impedance, PCT, signal slope, or sensing were recorded. There were no increases of serum troponin I after the MRI examination. Conclusions MRI of the brain may be performed safely at 1.5 T using a T/R head coil in case of an urgent clinical need in patients with TTPL and may be considered a feasible and safe procedure when appropriate precautionary measures are taken.

2021 ◽  
Vol 15 ◽  
Author(s):  
Yuna Chen ◽  
Yongsheng Pan ◽  
Shangyu Kang ◽  
Junshen Lu ◽  
Xin Tan ◽  
...  

Diabetes with high blood glucose levels may damage the brain nerves and thus increase the risk of dementia. Previous studies have shown that dementia can be reflected in altered brain structure, facilitating computer-aided diagnosis of brain diseases based on structural magnetic resonance imaging (MRI). However, type 2 diabetes mellitus (T2DM)-mediated changes in the brain structures have not yet been studied, and only a few studies have focused on the use of brain MRI for automated diagnosis of T2DM. Hence, identifying MRI biomarkers is essential to evaluate the association between changes in brain structure and T2DM as well as cognitive impairment (CI). The present study aims to investigate four methods to extract features from MRI, characterize imaging biomarkers, as well as identify subjects with T2DM and CI.


Author(s):  
Hamed Samadi Ghoushchi ◽  
Yaghoub Pourasad

<p>The purpose of this article is to investigate techniques for classifying tumor grade from magnetic resonance imaging (MRI). This requires early diagnosis of the brain tumor and its grade. Magnetic resonance imaging may show a clear tumor in the brain, but doctors need to measure the tumor in order to treat more or to advance treatment. For this purpose, digital imaging techniques along with machine learning can help to quickly identify tumors and also treatments and types of surgery. These combined techniques in understanding medical images for researchers are an important tool to increase the accuracy of diagnosis. In this paper, classification methods for MRI images of tumors of the human brain are performed to review the astrocytoma-containing glands. Methods used to classify brain tumors, including preprocessing, screening, tissue extraction, and statistical features of the tumor using two types of T<sub>1</sub>W and Flair brain MRI images and also the method of dimensionality reduction of extracted features and how to train them in classification are also explained. Determine the tumor area using three classification of Fuzzy Logic <em>C</em><em>-</em><em>Means</em><em> </em>Clustering (FCM), Probabilistic Neural Networks (PNN) and Support Vector Machines (SVM). In this paper, simulated and real MRI images are used. The results obtained from the proposed methods in this paper are compared with the reference results and the results show that the proposed approach can increase the reliability of brain tumor diagnosis.</p>


2018 ◽  
Vol 33 (5) ◽  
pp. 313-319 ◽  
Author(s):  
Pradip P. Kamat ◽  
Marie K. Karaga ◽  
Benjamin L. Wisniewski ◽  
Courtney E. McCracken ◽  
Harold K. Simon ◽  
...  

Objective: To quantify the number of personnel, time to induce and complete sedation using propofol for outpatient magnetic resonance imaging (MRI) of the brain, and the frequency of serious adverse events (SAEs) in children with autism spectrum disorder (ASD) compared with children without ASD. Results: Baseline characteristics were the same between both groups. Overall sedation success was 99%. Although most children were sedated with ≤3 providers, 10% with ASD needed ≥4 providers (P = .005). The duration of sedation was less for the ASD group compared with the non-ASD group (49 minutes vs 56 minutes, P = .005). There was no difference in SAE frequency between groups (ASD 14% vs non-ASD 16%, P = .57). Conclusion: Children with ASD can be sedated for brain MRI using propofol with no increased frequency of SAEs compared with children without ASD. Sedation teams should anticipate that 10% of children with ASD may need additional personnel before propofol induction.


2006 ◽  
Vol 64 (4) ◽  
pp. 1033-1035 ◽  
Author(s):  
Emerson L. Gasparetto ◽  
Juliana Mecunhe Rosa ◽  
Taísa Davaus ◽  
Arnolfo de Carvalho Neto

OBJECTIVE: To report a case of childhood cerebral X-linked adrenoleukodystrophy (X-ADL), emphasizing the magnetic resonance imaging (MRI) findings at initial evaluation and at the follow-up. CASE REPORT: Five year-old boy, who was asymptomatic, presented with diagnosis of X-ADL for MRI evaluation. The initial brain MRI showed a focal area of enhancement at the splenium of the corpus calosum. One year later, the follow-up MRI showed a progression of the corpus calosus lesion, as well as other lesions in the parietal and occipital lobes. CONCLUSION: The brain MRI follow-up of patients with X-ADL is important to show the progression of the lesions.


Sensors ◽  
2022 ◽  
Vol 22 (1) ◽  
pp. 372
Author(s):  
Muhannad Faleh Alanazi ◽  
Muhammad Umair Ali ◽  
Shaik Javeed Hussain ◽  
Amad Zafar ◽  
Mohammed Mohatram ◽  
...  

With the advancement in technology, machine learning can be applied to diagnose the mass/tumor in the brain using magnetic resonance imaging (MRI). This work proposes a novel developed transfer deep-learning model for the early diagnosis of brain tumors into their subclasses, such as pituitary, meningioma, and glioma. First, various layers of isolated convolutional-neural-network (CNN) models are built from scratch to check their performances for brain MRI images. Then, the 22-layer, binary-classification (tumor or no tumor) isolated-CNN model is re-utilized to re-adjust the neurons’ weights for classifying brain MRI images into tumor subclasses using the transfer-learning concept. As a result, the developed transfer-learned model has a high accuracy of 95.75% for the MRI images of the same MRI machine. Furthermore, the developed transfer-learned model has also been tested using the brain MRI images of another machine to validate its adaptability, general capability, and reliability for real-time application in the future. The results showed that the proposed model has a high accuracy of 96.89% for an unseen brain MRI dataset. Thus, the proposed deep-learning framework can help doctors and radiologists diagnose brain tumors early.


2007 ◽  
Vol 13 (2) ◽  
pp. 186-192 ◽  
Author(s):  
José A Cabrera-Gómez ◽  
L Quevedo-Sotolongo ◽  
A González-Quevedo ◽  
S Lima ◽  
Y Real-González ◽  
...  

Background Some studies showed abnormalities in brain magnetic resonance imaging (MRI) of relapsing neuromyelitis optica (R-NMO) from 12 to 46%. These abnormalities are described as compatible/non-compatible with multiple sclerosis (MS). Objective To describe the abnormal brain MRI lesions in R-NMO with imaging studies conducted with more sensitive white matter change techniques. Methods Thirty patients with R-NMO were selected. All MRI brain studies were performed with a 1.5-T Siemens MRI system according to the Standardized MR Imaging Protocol for Multiple Sclerosis from the Consortium of MS Centers Consensus Guidelines. Results Brain MRI images were evaluated in 29 R-NMO cases because in one case the MRI images were not appropriate for the study. Of these 29 brain MRI studies, 19 cases (65.5%) had at least one or more lesions (1–57) and 10 were negative (34.4%). Brain MRI findings in 19 cases were characterized in T2/fluid-attenuated inversion-recovery (FLAIR) by the presence of subcortical/deep white matter lesions in 16 (84.2%) cases (1–50), most of them < 3 mm and without juxtacortical localization. Periventricular lesions were observed in 13 (68.4%) cases, but morphologically they were not oval, ovoid or perpendicularly orientated. Infratentorial lesions, all >3 mm, were observed in 4 (21.05%) cases without cerebellar involvement. T1 studies demonstrated absence of hypointense regions. Optic nerve enhancement was observed in 6/19 patients (31.5%). None of the brain MRI abnormalities observed were compatible with Barkhof et al. criteria of MS. Conclusions This study, based on a Cuban patient population, with long duration of disease, good sample size and detailed characterization by MRI, demonstrated the brain MRI pattern of R-NMO patients, which is different from MS. Multiple Sclerosis 2007; 13: 186–192. http://msj.sagepub.com


2018 ◽  
Vol 7 (3) ◽  
pp. 217-221
Author(s):  
E. V. Shevchenko ◽  
G. R. Ramazanov ◽  
S. S. Petrikov

Background Acute dizziness may be the only symptom of stroke. Prevalence of this disease among patients with isolated dizziness differs significantly and depends on study design, inclusion criteria and diagnostic methods. In available investigations, we did not find any prospective studies where magnetic resonance imaging, positional maneuvers, and Halmagyi-Curthoys test had been used to clarify a pattern of diseases with isolated acute dizziness and suspected stroke.Aim of study To clarify the pattern of the causes of dizziness in patients with suspected acute stroke.Material and methods We examined 160 patients admitted to N.V. Sklifosovsky Research Institute for Emergency Medicine with suspected stroke and single or underlying complaint of dizziness. All patients were examined with assessment of neurological status, Dix-Hollpike and Pagnini-McClure maneuvers, HalmagyiCurthoys test, triplex scans of brachiocephalic arteries, transthoracic echocardiography, computed tomography (CT) and magnetic resonance imaging (MRI) of the brain with magnetic field strength 1.5 T. MRI of the brain was performed in patients without evidence of stroke by CT and in patients with stroke of undetermined etiology according to the TOAST classification.Results In 16 patients (10%), the cause of dizziness was a disease of the brain: ischemic stroke (n=14 (88%)), hemorrhage (n=1 (6%)), transient ischemic attack (TIA) of posterior circulation (n=1 (6%)). In 70.6% patients (n=113), the dizziness was associated with peripheral vestibulopathy: benign paroxysmal positional vertigo (n=85 (75%)), vestibular neuritis (n=19 (17%)), Meniere’s disease (n=7 (6%)), labyrinthitis (n=2 (1,3%)). In 6.9% patients (n=11), the cause of dizziness was hypertensive encephalopathy, 1.9% of patients (n=3) had heart rhythm disturbance, 9.4% of patients (n=15) had psychogenic dizziness, 0.6% of patients (n=1) had demyelinating disease, and 0.6% of patients (n=1) had hemic hypoxia associated with iron deficiency anemia.Conclusion In 70.6% patients with acute dizziness, admitted to hospital with a suspected stroke, peripheral vestibulopathy was revealed. Only 10% of patients had a stroke as a cause of dizziness.


2020 ◽  
Author(s):  
Huynh Quang Huy

BACKGROUND It is important to identify the neuroimaging features that are associated with partial epilepsy in preschool children. Advances in technology recently to localize focal epileptogenic lesions, especially that of high-resolution structural imaging with magnetic resonance imaging (MRI). The recommendation that electroencephalography (EEG) should be gold criteria and that M.R.I should be optional has been questioned. OBJECTIVE The present study aims to to explore the brain lesions on MRI and its association to electroencephalogram in children with partial epilepsy. METHODS The present study was conducted among 112 preschool children with history of partial seizures. All patients underwent EEG and brain MRI. The epileptogenic lesions were identified on the basis of the signal intensities and morphological abnormalities seen on MRI. The correlation between MRI and EEG abnormalities was explored using a chi-square test. RESULTS Abnormal MRI were found in 34.8% (n = 39) of the sample. The EEG and MRI agreed with respect to classify into abnormal or normal in 48.2% (n = 54). Of the 27 patients with a normal EEG, six (22.2%) were seen to have an abnormal MRI. CONCLUSIONS A number of MRI abnormalities was found in our study of otherwise normal children, although the correlation between these results was not clear. Follow-up of these children will help us identify the important abnormalities. Despite of small sample, our results showed that a normal E.E.G findings does not predict a normal brain MRI in children with partial epilepsy.


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