scholarly journals MRI With Gadolinium as a Measure of Blood-Labyrinth Barrier Integrity in Patients With Inner Ear Symptoms: A Scoping Review

2021 ◽  
Vol 12 ◽  
Author(s):  
Christopher I. Song ◽  
Jacob M. Pogson ◽  
Nicholas S. Andresen ◽  
Bryan K. Ward
Keyword(s):  
Inner Ear ◽  
Scoping Review ◽  
Signal Intensity ◽  
Animal Studies ◽  
Convincing Evidence ◽  
Clinical Settings ◽  
Enhanced Mri ◽  
Capillary Barriers ◽  
Magnetic Resonance Imaging Mri ◽  
Ear Symptoms

Objective: Capillaries within the inner ear form a semi-permeable barrier called the blood-labyrinth barrier that is less permeable than capillary barriers elsewhere within the human body. Dysfunction of the blood-labyrinth barrier has been proposed as a mechanism for several audio-vestibular disorders. There has been interest in using magnetic resonance imaging (MRI) with intravenous gadolinium-based contrast agents (GBCA) as a marker for the integrity of the blood labyrinth barrier in research and clinical settings. This scoping review evaluates the evidence for using intravenous gadolinium-enhanced MRI to assess the permeability of the blood-labyrinth barrier in healthy and diseased ears.Methods: A systematic search was conducted of three databases: PubMed, EMBASE, CINAHL PLUS. Studies were included that used GBCA to study the inner ear and permeability of the blood-labyrinth barrier. Data was collected on MRI protocols used and inner ear enhancement patterns of healthy and diseased ears in both human and animal studies.Results: The search yielded 14 studies in animals and 53 studies in humans. In healthy animal and human inner ears, contrast-enhanced MRI demonstrated gradual increase in inner ear signal intensity over time that was limited to the perilymph. Signal intensity peaked at 100 min in rodents and 4 h in humans. Compared to controls, patients with idiopathic sudden sensorineural hearing loss and otosclerosis had increased signal intensity both before and shortly after GBCA injection. In patients with Ménière's disease and vestibular schwannoma, studies reported increased signal at 4 h, compared to controls. Quality assessment of included studies determined that all the studies lacked sample size justification and many lacked adequate control groups or blinded assessors of MRI.Conclusions: The included studies provided convincing evidence that gadolinium crosses the blood-labyrinth barrier in healthy ears and more rapidly in some diseased ears. The timing of increased signal differs by disease. There was a lack of evidence that these findings indicate general permeability of the blood-labyrinth barrier. Future studies with consistent and rigorous methods are needed to investigate the relationship between gadolinium uptake and assessments of inner ear function and to better determine whether signal enhancement indicates permeability for molecules other than gadolinium.

scholarly journals Repeated electromagnetic field stimulation lowers amyloid-β peptide levels in primary human mixed brain tissue cultures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Felipe P. Perez ◽  
Bryan Maloney ◽  
Nipun Chopra ◽  
Jorge J. Morisaki ◽  
Debomoy K. Lahiri
Keyword(s):  
Electromagnetic Field ◽  
Late Onset ◽  
Amyloid Β ◽  
Clinical Settings ◽  
Amyloid Β Peptide ◽  
Field Stimulation ◽  
Amino Acid Residues ◽  
Hyperphosphorylated Tau Protein ◽  
Magnetic Resonance Imaging Mri

AbstractLate Onset Alzheimer’s Disease is the most common cause of dementia, characterized by extracellular deposition of plaques primarily of amyloid-β (Aβ) peptide and tangles primarily of hyperphosphorylated tau protein. We present data to suggest a noninvasive strategy to decrease potentially toxic Aβ levels, using repeated electromagnetic field stimulation (REMFS) in primary human brain (PHB) cultures. We examined effects of REMFS on Aβ levels (Aβ40 and Aβ42, that are 40 or 42 amino acid residues in length, respectively) in PHB cultures at different frequencies, powers, and specific absorption rates (SAR). PHB cultures at day in vitro 7 (DIV7) treated with 64 MHz, and 1 hour daily for 14 days (DIV 21) had significantly reduced levels of secreted Aβ40 (p = 001) and Aβ42 (p = 0.029) peptides, compared to untreated cultures. PHB cultures (DIV7) treated at 64 MHz, for 1 or 2 hour during 14 days also produced significantly lower Aβ levels. PHB cultures (DIV28) treated with 64 MHz 1 hour/day during 4 or 8 days produced a similar significant reduction in Aβ40 levels. 0.4 W/kg was the minimum SAR required to produce a biological effect. Exposure did not result in cellular toxicity nor significant changes in secreted Aβ precursor protein-α (sAPPα) levels, suggesting the decrease in Aβ did not likely result from redirection toward the α-secretase pathway. EMF frequency and power used in our work is utilized in human magnetic resonance imaging (MRI, thus suggesting REMFS can be further developed in clinical settings to modulate Aβ deposition.

scholarly journals A Cell-Based Approach to Dental Pulp Regeneration Using Mesenchymal Stem Cells: A Scoping Review

2021 ◽  
Vol 22 (9) ◽  
pp. 4357
Author(s):  
Sahng G. Kim
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Scoping Review ◽  
Clinical Studies ◽  
Dental Pulp ◽  
Animal Studies ◽  
Risk Of Bias ◽  
Pulp Regeneration

Despite the recent explosion of investigations on dental pulp regeneration using various tissue engineering strategies, the translation of the findings from such studies into therapeutic applications has not been properly achieved. The purpose of this scoping review was to systematically review the efficacy of mesenchymal stem cell transplantation for dental pulp regeneration. A literature search was conducted using five electronic databases from their inception to January 2021 and supplemented by hand searches. A total of 17 studies, including two clinical trials and 15 animal studies using orthotopic pulp regeneration models, were included for the review. The risk of bias for the individual studies was assessed. This scoping review demonstrated that the regeneration of vascularized pulp-like tissue was achieved using the stem cell transplantation strategy in animal models. Autologous cell transplantation in two clinical studies also successfully regenerated vascularized vital tissue. Dental pulp stem cell subpopulations, such as mobilized dental pulp stem cells, injectable scaffolds such as atelocollagen, and a granulocyte-colony forming factor, were the most commonly used for pulp regeneration. The overall risk of bias was unclear for animal studies and was moderate or judged to raise some concerns for clinical studies. More high-quality clinical studies are needed to further determine the safety and efficacy of the stem cell transplantation strategy for dental pulp regeneration.

Could we assess the functional status, of hormone secreting, or non-secreting of the adrenal masses regarding their Magnetic Resonance Imaging (MRI) characteristics?

2021 ◽  
Vol 22 ◽  
Author(s):  
Gamze Akkus ◽  
Ferhat Piskin ◽  
Barış Karagun ◽  
Murat Sert ◽  
Mehtap Evran ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Functional Status ◽  
Signal Intensity ◽  
Adrenal Mass ◽  
Resonance Imaging ◽  
Intensity Index ◽  
Adrenal Masses ◽  
Magnetic Resonance Imaging Mri

Background: Diagnostic imaging techniques including magnetic resonance imaging (MRI) should also perform on all patients with incidentalomas. However, there is a limited study whether the quantitative measurements (signal intensity index, adrenal to spleen ratio) in MRI could predict the functional status of adrenal adenomas. Material-Method: Between 2015-2020; 404 patients (265 females, 139 males) with adrenal mass who were referred to the university hospital for further investigation were included. After detailed diagnostic hormonal evaluation, all patients underwent MRI 1.5 T device (Signa, GE Medical Systems; Milwaukee, USA). The signal intensities of the adrenal lesions on T2W images were qualitatively evaluated and noted as homogenous or heterogeneous in comparison with the liver signal intensity (SI). A chemical-shift SI index and chemical shift adrenal-to-spleen SI ratio were also calculated. Results: While 331(81.9%) of the patients had nonfunctional adrenal mass, the rest of them (n=73, 18.1%) were patients with functional (autonomous cortisol secretion-ACS, cushing syndrome-CS, pheochromocytoma, primary hyperaldosteronism-PA) adrenal masses. In phase vs phase values of patients with NFAI, Pheo(n=17), ACS (n=30), CS (n=11), and PA (n=15) were 474.04±126.7 vs 226.6±132.4, 495.3±182.8 vs 282.17±189.1, 445.2±134.8 vs 203.3±76.2, 506.8±126.5 vs 212.2±73.6 and 496.2±147.5 vs 246.6±102.1, respectively. Mean signal intensity index (SII) and adrenal to spleen ratio (ASR) of all groups (NFAI, Pheo, ACS, CS, PA) were 52.0±24.8 and 0.51, 44.9±22.5 and 0.55, 49.5±24.5 and 0.53, 56.2±16.4 and 0.43, 47.6±25.1 and 0.54, respectively. Based the current accepted measurements in the case of ASR and SII, all lesions were similar and shown as fat rich adenomas (p*= 0.552, p** = 0.45). Conclusion: The quantitative assessment (SII, ASR) of intracellular lipids in an incidentally discovered adrenal tumour could only help distinguish adrenal masses in case of adenomas or non-adenomas As initial diagnostic evaluation, clinical and laboratory assessment ,to distinguish hormone secretion, should be taken in all patients with adrenal incidentalomas.

Imaging of rare appendicular non-acral soft-tissue chondromas in adults with histopathologic correlation

2017 ◽  
Vol 59 (6) ◽  
pp. 700-708
Author(s):  
Mohamed Ragab Nouh ◽  
Hanan Abd El-Aziz Amr ◽  
Rola H Ali
Keyword(s):  
Soft Tissue ◽  
Signal Intensity ◽  
Tissue Reaction ◽  
High Signal ◽  
Diagnostic Challenge ◽  
Post Contrast ◽  
Intensity Matrix ◽  
Tissue Edema ◽  
Magnetic Resonance Imaging Mri

Background Soft-tissue chondroma (STC) is a rare benign soft tissue tumor that arises primarily in acral extra-skeletal locations. Occasionally, STCs may arise in more proximal non-acral locations, accompanied by non-classic features that label them as indeterminate lesions and pose diagnostic challenge for both radiologists and pathologists alike. Purpose To explicate the potential of diagnostic imaging in the identification and characterization of appendicular non-acral STCs with emphasis on their morphologic magnetic resonance imaging (MRI) enhancement. Material and Methods Our clinical database records were searched for patients with histologically proven primary soft-tissue chondroid lesions over a five-year period. Two musculoskeletal (MSK) trained radiologists evaluated the imaging studies and an MSK pathologist revised the pathological findings. Results The study included six cases of appendicular non-acral STCs (mean age = 40.5 years). The mean size of the tumors was 5.6 cm, with four localized to the knee region, one in the thigh, and one in the sternoclavicular region. All cases showed high signal intensity matrix with low-signal intensity septa on T2-weighted MRI and post-contrast marginal/septal enhancement. The lesions were lobulated and lacked host tissue reaction except for one showing subjacent mild soft-tissue edema. Histologically, the cases lacked overt features of malignancy although one was originally misdiagnosed as chondrosarcoma. Conclusion Non-acral STCs are benign cartilaginous tumors that may pose a diagnostic challenge, both radiologically and pathologically. Collaborative imaging and pathologic workup is needed for better characterization of non-aggression of these lesions, and to avoid diagnostic pitfalls and unnecessary radical resections.

scholarly journals Longitudinal structural and functional brain development in childhood and adolescence

2018 ◽  
Author(s):  
Kathryn L. Mills ◽  
Christian K. Tamnes
Keyword(s):  
Brain Development ◽  
Animal Studies ◽  
Diffusion Tensor ◽  
Childhood And Adolescence ◽  
Structural Development ◽  
Social Environments ◽  
Brain Structure And Function ◽  
Magnetic Resonance Imaging Mri ◽  
Methodological Considerations ◽  
And Function

The development of the human brain involves a prolonged course of maturation, enabling us to learn to navigate our complex social environments. Here, we give short introductions to post-mortem and animal studies on postnatal brain development and selected methodological considerations for longitudinal developmental neuroimaging. We then describe typical developmental changes in brain structure and function from childhood to adulthood. We focus on measurements derived from magnetic resonance imaging (MRI) and on longitudinal data. Specifically, we discuss brain structural development based on morphometry and diffusion tensor imaging (DTI) studies, and functional development based on resting-state and task-based functional MRI. Finally, we highlight selected current overarching research questions and argue that an important step in answering these questions is to study individual differences in longitudinal brain development.

scholarly journals Information and communication technology-based interventions for suicide prevention implemented in clinical settings: A scoping review protocol

2021 ◽  
Author(s):  
Hwayeon Danielle Shin ◽  
Juveria Zaheer ◽  
Terri Rodak ◽  
John Torous ◽  
Gillian Strudwick
Keyword(s):  
Information And Communication Technology ◽  
Suicide Prevention ◽  
Communication Technology ◽  
Scoping Review ◽  
Implementation Strategies ◽  
Mobile App ◽  
Barriers And Facilitators ◽  
Clinical Settings ◽  
Scoping Reviews ◽  
Information And Communication

IntroductionThere is a surplus of Information and Communication Technology (ICT)-based interventions for suicide prevention. However, it is unclear which of these ICT-based interventions for suicide prevention have been implemented in clinical settings. Furthermore, evidence shows that implementation strategies have often been mismatched to existing barriers. In response, the authors recognize the critical need for prospectively assessing the barriers and facilitators and then strategically developing implementation strategies. This review is part of a multi-phase project to develop and test tailored implementation strategies for mobile app-based suicide prevention in clinical settings. The overall objective of this scoping review is to identify and characterize ICT-based interventions for all levels of suicide prevention in clinical settings. Additionally, this review will identify and characterize the barriers and facilitators to implementing these ICT-based interventions as well as reported measures and outcomes. The findings will directly inform the subsequent phase to maximize implementation and inform future efforts for implementing other types of ICT-based interventions related to suicide prevention in clinical settings.Methods and analysis This review will adhere to the methods described by the Joanna Briggs Institute for conducting scoping reviews. The reporting will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for scoping reviews checklist. The following databases will be searched: Medline, PsycInfo, Embase, CINAHL, Web of Science, and LISTA. Two reviewers will independently screen the articles and extract data using a standardised data collection tool. Then, authors will characterize extracted data using frameworks, typology, and taxonomies to address the proposed review questions. Ethics and disseminationEthics approval is not required for this scoping review. Authors will share the results in a peer-reviewed, open access publication, and conference presentations. Furthermore, the findings will be shared with relevant health organizations through lay language summaries and informal presentations.

scholarly journals Diagnostic value of magnetic resonance imaging in the analysis of ameloblastoma: report of two cases

2019 ◽  
Vol 22 (3) ◽  
pp. 425-431
Author(s):  
Neiandro Santos Galvão ◽  
Antonione Santos Bezerra Pinto ◽  
Alan Leandro Carvalho Farias ◽  
André Luiz Ferreira Costa ◽  
Sérgio Lúcio Pereira de Castro Lopes ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Differential Diagnosis ◽  
Magnetic Resonance ◽  
Signal Intensity ◽  
Diagnostic Value ◽  
Resonance Imaging ◽  
Intermediate Signal Intensity ◽  
Additional Information ◽  
Imaging Characteristics ◽  
Magnetic Resonance Imaging Mri

Ameloblastoma is an odontogenic tumor that shares clinical and imaging characteristics with other lesions of the jaws, such as odontogenic keratocyst, which makes the diagnosis difficult. However, in addition to radiographic and tomographic examinations, Magnetic Resonance Imaging (MRI) has been increasingly used, contributing with relevant additional information about the differentiation between solid and liquid components of the lesion. This case report was conducted to present two variations of ameloblastoma and discuss the radiographic, tomographic and MRI contribution in the differential diagnosis between ameloblastoma and odontogenic keratocyst.The signal intensity in T1-weighted MRI revealed internal fluid content in both cases, which was important in the differential diagnosis with other intraosseous lesions such as odontogenic keratocysts. This is probably due to the presence of keratin that increases the viscosity of the content and also for an intermediate signal intensity signal in T2-weighted MRI. Therefore, MRI revealed important internal characteristics of the reported lesions, which was very useful in the establishment of the differential diagnosis with other lesions.

Inner ear symptoms: can we use them to approach cardiovascular diseases?

2014 ◽  
Vol 9 (8) ◽  
pp. 825-827 ◽  
Author(s):  
Antonio Pirodda ◽  
Arrigo Francesco Giuseppe Cicero ◽  
Cristina Brandolini ◽  
Claudio Borghi
Keyword(s):  
Cardiovascular Diseases ◽  
Inner Ear ◽  
Ear Symptoms
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