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Neurosurgical Review Apr 2022Magnetic resonance elastography (MRE) of the brain allows quantitative measurement of tissue mechanics. Multiple studies are exploring possible applications in normal... (Review)
Review
BACKGROUND
Magnetic resonance elastography (MRE) of the brain allows quantitative measurement of tissue mechanics. Multiple studies are exploring possible applications in normal pressure hydrocephalus (NPH) in clinical and paraclinical contexts. This is of great interest in neurological surgery due to challenges related to diagnosis and prediction of treatment effects. In this scoping review, we present a topical overview and discuss the current literature, with particular attention to clinical implications and current challenges.
METHODS
The protocol was based on the PRISMA extension for scoping reviews. After a systematic database search (PubMed, Embase, and Web of Science), the articles were screened for relevance. Thirty articles were subject to detailed screening, and key technical and clinical data items were extracted. The inclusion criteria included the use of MRE on human subjects with NPH.
RESULTS
Seven articles were included in the final study. These studies had various objectives including the role of MRE in the assessment of regional elastic changes in NPH, shunt effect, and evaluation of NPH symptoms. MRE revealed patterns of mechanical changes in NPH that differed from other dementias. Regional MRE changes were associated with specific NPH signs and symptoms. Neurosurgical shunting caused partial normalization in tissue scaffold parameters. The studies were highly heterogeneous in technical aspects and design.
CONCLUSION
MRE studies in NPH are still limited by few participants, variable cohorts, inconsistent methodologies, and technical challenges, but the approach shows great potential for future clinical application.
Topics: Brain; Elasticity Imaging Techniques; Humans; Hydrocephalus, Normal Pressure; Magnetic Resonance Imaging
PubMed: 34687356
DOI: 10.1007/s10143-021-01669-0 -
Medicina (Kaunas, Lithuania) Jan 2023: The heart is the organ with the highest metabolic demand in the body, and it relies on high ATP turnover and efficient energy substrate utilisation in order to... (Review)
Review
: The heart is the organ with the highest metabolic demand in the body, and it relies on high ATP turnover and efficient energy substrate utilisation in order to function normally. The derangement of myocardial energetics may lead to abnormalities in cardiac metabolism, which herald the symptoms of heart failure (HF). In addition, phosphorus magnetic resonance spectroscopy (P MRS) is the only available non-invasive method that allows clinicians and researchers to evaluate the myocardial metabolic state in vivo. This review summarises the importance of myocardial energetics and provides a systematic review of all the available research studies utilising P MRS to evaluate patients with a range of cardiac pathologies. : We have performed a systematic review of all available studies that used P MRS for the investigation of myocardial energetics in cardiovascular disease. : A systematic search of the Medline database, the Cochrane library, and Web of Science yielded 1092 results, out of which 62 studies were included in the systematic review. The P MRS has been used in numerous studies and has demonstrated that impaired myocardial energetics is often the beginning of pathological processes in several cardiac pathologies. : The P MRS has become a valuable tool in the understanding of myocardial metabolic changes and their impact on the diagnosis, risk stratification, and prognosis of patients with cardiovascular diseases.
Topics: Humans; Phosphorus; Cardiovascular Diseases; Magnetic Resonance Spectroscopy; Myocardium; Heart Failure; Energy Metabolism
PubMed: 36676798
DOI: 10.3390/medicina59010174 -
Pacing and Clinical Electrophysiology :... Jul 2016One-third of all patients with heart failure have nonischemic dilated cardiomyopathy (NIDM). Five-year mortality from NIDM is as high as 20% with sudden cardiac death... (Meta-Analysis)
Meta-Analysis Review
One-third of all patients with heart failure have nonischemic dilated cardiomyopathy (NIDM). Five-year mortality from NIDM is as high as 20% with sudden cardiac death (SCD) as the cause in 30% of the deaths. Currently, the left ventricular ejection fraction (LVEF) is used as the main criteria to risk stratify patients requiring an implantable cardioverter defibrillator (ICD) to prevent SCD. However, LVEF does not necessarily reflect myocardial propensity for electrical instability leading to ventricular tachycardia (VT) or ventricular fibrillation (VF). Due to the differential risk in various subgroups of patients for arrhythmic death, it is important to identify appropriate patients for ICD implantation so that we can optimize healthcare resources and avoid the complications of ICDs in individuals who are unlikely to benefit. We performed a systematic search and review of clinical trials of NIDM and the use of ICDs and cardiac magnetic resonance imaging with late gadolinium enhancement (LGE) for risk stratification. LGE identifies patients with NIDM who are at high risk for SCD and enables optimized patient selection for ICD placement, while the absence of LGE may reduce the need for ICD implantation in patients with NIDM who are at low risk for future VF/VT or SCD.
Topics: Adult; Aged; Aged, 80 and over; Cardiomyopathy, Dilated; Comorbidity; Contrast Media; Death, Sudden, Cardiac; Gadolinium; Heart Failure; Humans; Magnetic Resonance Imaging, Cine; Middle Aged; Prevalence; Reproducibility of Results; Risk Factors; Sensitivity and Specificity; Survival Rate
PubMed: 27071516
DOI: 10.1111/pace.12873 -
Frontiers in Neurology 2023There is conflicting published research about the clinical effectiveness of repetitive transcranial magnetic stimulation (rTMS) for the treatment of post-stroke...
OBJECTIVE
There is conflicting published research about the clinical effectiveness of repetitive transcranial magnetic stimulation (rTMS) for the treatment of post-stroke depression (PSD). In order to provide trustworthy information for upcoming therapeutic treatments, this review attempts to compile and assess the data from pertinent systematic reviews and meta-analyses.
METHODS
The systematic evaluation of repetitive transcranial magnetic stimulation for post-stroke depression was collected by searching CNKI, VIP, Wanfang Database, CBM, PubMed, EMBASE, Web of Science, and Cochrane Library. The retrieval time is from database construction to September 2022. After selection, the included literature was evaluated for methodological quality, reporting quality, and evidence quality using AMSTAR2, PRISMA statements, and the GRADE system.
RESULTS
There were a total of 13 studies included, with three having generally comprehensive reporting according to the PRISMA statement, eight having some reporting issues, two having pretty substantial information issues, and 13 having extremely poor methodological quality according to the AMSTAR2. The GRADE was used to grade the quality of the evidence, and the included literature had 0 high-level evidence, eight medium-level evidence, 12 low-level evidence, and 22 very low-level evidence.
LIMITATIONS
The results of this study are from researchers' subjective evaluation and only qualitative analysis, not quantitative evaluation. Although repeated cross-evaluation of researchers is carried out, the results will be personal. The interventions included in the study were complex, and it was impossible to analyze their effect values quantitatively.
CONCLUSION
Patients with post-stroke depression may benefit from repetitive transcranial magnetic stimulation. However, in terms of the quality of the reports, the methodology, and the quality of the evidence, published systematic evaluations/meta-analyses are of low quality. We list the drawbacks of the current clinical trials of repetitive transcranial magnetic stimulation for post-stroke depression as well as potential therapeutic mechanisms. This information may serve as a guide for future clinical trials aiming to establish a solid foundation for the clinical efficacy of repetitive transcranial magnetic stimulation in the treatment of post-stroke depression.
PubMed: 37006488
DOI: 10.3389/fneur.2023.930558 -
Sensors (Basel, Switzerland) Dec 2021Owing to the hasty growth of communication technologies in the Underwater Internet of Things (UIoT), many researchers and industries focus on enhancing the existing... (Review)
Review
Owing to the hasty growth of communication technologies in the Underwater Internet of Things (UIoT), many researchers and industries focus on enhancing the existing technologies of UIoT systems for developing numerous applications such as oceanography, diver networks monitoring, deep-sea exploration and early warning systems. In a constrained UIoT environment, communication media such as acoustic, infrared (IR), visible light, radiofrequency (RF) and magnet induction (MI) are generally used to transmit information via digitally linked underwater devices. However, each medium has its technical limitations: for example, the acoustic medium has challenges such as narrow-channel bandwidth, low data rate, high cost, etc., and optical medium has challenges such as high absorption, scattering, long-distance data transmission, etc. Moreover, the malicious node can steal the underwater data by employing blackhole attacks, routing attacks, Sybil attacks, etc. Furthermore, due to heavyweight, the existing privacy and security mechanism of the terrestrial internet of things (IoT) cannot be applied directly to UIoT environment. Hence, this paper aims to provide a systematic review of recent trends, applications, communication technologies, challenges, security threats and privacy issues of UIoT system. Additionally, this paper highlights the methods of preventing the technical challenges and security attacks of the UIoT environment. Finally, this systematic review contributes much to the profit of researchers to analyze and improve the performance of services in UIoT applications.
Topics: Acoustics; Computer Security; Internet of Things; Privacy; Technology
PubMed: 34960366
DOI: 10.3390/s21248262 -
Pharmaceutics Jul 2023The incidence of gastrointestinal cancers has increased in recent years. Current treatments present numerous challenges, including drug resistance, non-specificity, and... (Review)
Review
The incidence of gastrointestinal cancers has increased in recent years. Current treatments present numerous challenges, including drug resistance, non-specificity, and severe side effects, needing the exploration of new therapeutic strategies. One promising avenue is the use of magnetic nanoparticles, which have gained considerable interest due to their ability to generate heat in tumor regions upon the application of an external alternating magnetic field, a process known as hyperthermia. This review conducted a systematic search of in vitro and in vivo studies published in the last decade that employ hyperthermia therapy mediated by magnetic nanoparticles for treating gastrointestinal cancers. After applying various inclusion and exclusion criteria (studies in the last 10 years where hyperthermia using alternative magnetic field is applied), a total of 40 articles were analyzed. The results revealed that iron oxide is the preferred material for magnetism generation in the nanoparticles, and colorectal cancer is the most studied gastrointestinal cancer. Interestingly, novel therapies employing nanoparticles loaded with chemotherapeutic drugs in combination with magnetic hyperthermia demonstrated an excellent antitumor effect. In conclusion, hyperthermia treatments mediated by magnetic nanoparticles appear to be an effective approach for the treatment of gastrointestinal cancers, offering advantages over traditional therapies.
PubMed: 37514144
DOI: 10.3390/pharmaceutics15071958 -
Frontiers in Aging Neuroscience 2022To investigate the association between diffusion tensor imaging (DTI) findings and domain-specific cognitive impairment in cerebral small vessel disease (CSVD).
OBJECTIVE
To investigate the association between diffusion tensor imaging (DTI) findings and domain-specific cognitive impairment in cerebral small vessel disease (CSVD).
METHODS
Databases such as PubMed, Excerpta Medical Database (EMBASE), Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure Databases (CNKI), Wanfang, Chinese Biomedical Literature Database (SinoMed), and Chongqing Chinese Science and Technology Periodical Database (VIP) were comprehensively retrieved for studies that reported correlation coefficients between cognition and DTI values. Random effects models and meta-regression were applied to account for heterogeneity among study results. Subgroup and publication bias analyses were performed using Stata software.
RESULTS
Seventy-seven studies involving 6,558 participants were included in our meta-analysis. The diagnosis classification included CSVD, white matter hyperintensities (WMH), subcortical ischemic vascular disease, cerebral microbleeding, cerebral amyloid angiopathy (CAA), cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and Fabry disease. The pooled estimates showed that the fractional anisotropy (FA)-overall exhibited a moderate correlation with general cognition, executive function, attention, construction, and motor performance ( = 0.451, 0.339, 0.410, and 0.319), and the mean diffusitivity/apparent diffusion coefficient (MD/ADC)-overall was moderately associated with general cognition, executive function, and memory ( = -0.388, -0.332, and -0.303, respectively; < 0.05). Moreover, FA in cingulate gyrus (CG), cerebral peduncle (CP), corona radiata (CR), external capsule (EC), frontal lobe (FL), fornix (FOR), internal capsule (IC), and thalamic radiation (TR) was strongly correlated with general cognition ( = 0.591, 0.584, 0.543, 0.662, 0.614, 0.543, 0.597, and 0.571), and a strong correlation was found between MD/ADC and CG ( = -0.526), normal-appearing white matter (NAWM; = -0.546), and whole brain white matter (WBWM; = -0.505). FA in fronto-occipital fasciculus (FOF) ( = 0.523) and FL ( = 0.509) was strongly associated with executive function. Only MD/ADC of the corpus callosum (CC) was strongly associated with memory ( = -0.730). Besides, FA in CG ( = 0.532), CC ( = 0.538), and FL ( = 0.732) was strongly related to the attention domain. Finally, we found that the sample size, etiology, magnetic resonance imaging (MRI) magnet strength, study type, and study quality contributed to interstudy heterogeneity.
CONCLUSION
Lower FA or higher MD/ADC values were related to more severe cognitive impairment. General cognition and executive function domains attracted the greatest interest. The FL was commonly examined and strongly associated with general cognition, executive function, and attention. The CC was strongly associated with memory and attention. The CG was strongly related to general cognition and attention. The CR, IC, and TR were also strongly related to general cognition. Indeed, these results should be validated in high-quality prospective studies with larger sample sizes.
SYSTEMATIC REVIEW REGISTRATION
http://www.crd.york.ac.uk/PROSPERO, identifier: CRD42021226133.
PubMed: 36483114
DOI: 10.3389/fnagi.2022.1019088 -
International Psychogeriatrics Nov 2023Behavioral and psychological symptoms of dementia (BPSD) are a group of noncognitive symptoms that occur commonly among individuals with dementia. These symptoms worsen... (Review)
Review
OBJECTIVE
Behavioral and psychological symptoms of dementia (BPSD) are a group of noncognitive symptoms that occur commonly among individuals with dementia. These symptoms worsen the morbidity and mortality among individuals with dementia and significantly increase the cost of caring for these individuals. Transcranial magnetic stimulation (TMS) has been shown to have some benefits in the treatment of BPSD. This review provides an updated summary of the effect of TMS on BPSD.
METHODS
We conducted a systematic review of PubMed, Cochrane, and Ovid databases on the use of TMS to treat BPSD.
RESULTS
We found 11 randomized controlled studies that evaluated the use of TMS among individuals with BPSD. Three of these studies examined the effect of TMS on apathy, two of which showed significant benefit. Seven studies showed that TMS significantly improves BPSD: six using repetitive transcranial magnetic stimulation (rTMS) and one using transcranial direct current stimulation (tDCS). Four studies, two evaluating tDCS, one evaluating rTMS, and one evaluating intermittent theta-burst stimulation (iTBS) showed a nonsignificant impact of TMS on BPSD. Adverse events were predominantly mild and transitory in all studies.
CONCLUSION
Available data from this review indicate that rTMS is beneficial for individuals with BPSD, especially among individuals with apathy, and is well tolerated. However, more data are needed to prove the efficacy of tDCS and iTBS. Additionally, more randomized controlled trials with longer treatment follow-up and standardized use of BPSD assessments are needed to determine the best dose, duration, and modality for effective treatment of BPSD.
Topics: Humans; Transcranial Magnetic Stimulation; Transcranial Direct Current Stimulation; Pain Management; Treatment Outcome; Dementia
PubMed: 36803624
DOI: 10.1017/S1041610223000091 -
Brain Communications 2022Myelin-sensitive MRI such as magnetization transfer imaging has been widely used in multiple sclerosis. The influence of methodology and differences in disease subtype... (Review)
Review
Myelin-sensitive MRI such as magnetization transfer imaging has been widely used in multiple sclerosis. The influence of methodology and differences in disease subtype on imaging findings is, however, not well established. Here, we systematically review magnetization transfer brain imaging findings in relapsing-remitting multiple sclerosis. We examine how methodological differences, disease effects and their interaction influence magnetization transfer imaging measures. Articles published before 06/01/2021 were retrieved from online databases (PubMed, EMBASE and Web of Science) with search terms including 'magnetization transfer' and 'brain' for systematic review, according to a pre-defined protocol. Only studies that used human quantitative magnetization transfer imaging in adults with relapsing-remitting multiple sclerosis (with or without healthy controls) were included. Additional data from relapsing-remitting multiple sclerosis subjects acquired in other studies comprising mixed disease subtypes were included in meta-analyses. Data including sample size, MRI acquisition protocol parameters, treatments and clinical findings were extracted and qualitatively synthesized. Where possible, effect sizes were calculated for meta-analyses to determine magnetization transfer (i) differences between patients and healthy controls; (ii) longitudinal change and (iii) relationships with clinical disability in relapsing-remitting multiple sclerosis. Eighty-six studies met inclusion criteria. MRI acquisition parameters varied widely, and were also underreported. The majority of studies examined the magnetization transfer ratio in white matter, but magnetization transfer metrics, brain regions examined and results were heterogeneous. The analysis demonstrated a risk of bias due to selective reporting and small sample sizes. The pooled random-effects meta-analysis across all brain compartments revealed magnetization transfer ratio was 1.17 per cent units (95% CI -1.42 to -0.91) lower in relapsing-remitting multiple sclerosis than healthy controls (-value: -8.99, < 0.001, 46 studies). Linear mixed-model analysis did not show a significant longitudinal change in magnetization transfer ratio across all brain regions [ = 0.12 (-0.56 to 0.80), -value = 0.35, = 0.724, 14 studies] or normal-appearing white matter alone [ = 0.037 (-0.14 to 0.22), -value = 0.41, = 0.68, eight studies]. There was a significant negative association between the magnetization transfer ratio and clinical disability, as assessed by the Expanded Disability Status Scale [ = -0.32 (95% CI -0.46 to -0.17); -value = -4.33, < 0.001, 13 studies]. Evidence suggests that magnetization transfer imaging metrics are sensitive to pathological brain changes in relapsing-remitting multiple sclerosis, although effect sizes were small in comparison to inter-study variability. Recommendations include: better harmonized magnetization transfer acquisition protocols with detailed methodological reporting standards; larger, well-phenotyped cohorts, including healthy controls; and, further exploration of techniques such as magnetization transfer saturation or inhomogeneous magnetization transfer ratio.
PubMed: 35652121
DOI: 10.1093/braincomms/fcac088 -
Pediatric Radiology Jan 2021Whole-body magnetic resonance imaging (MRI) is increasingly being used for a number of indications. Our aim was to review and describe indications and scan protocols for... (Review)
Review
Whole-body magnetic resonance imaging (MRI) is increasingly being used for a number of indications. Our aim was to review and describe indications and scan protocols for diagnostic value of whole-body MRI for multifocal disease in children and adolescents, we conducted a systematic search in Medline, Embase and Cochrane for all published papers until November 2018. Relevant subject headings and free text words were used for the following concepts: 1) whole-body, 2) magnetic resonance imaging and 3) child and/or adolescent. Included were papers in English with a relevant study design that reported on the use and/or findings from whole-body MRI examinations in children and adolescents. This review includes 54 of 1,609 papers identified from literature searches. Chronic nonbacterial osteomyelitis, lymphoma and metastasis were the most frequent indications for performing a whole-body MRI. The typical protocol included a coronal STIR (short tau inversion recovery) sequence with or without a coronal T1-weighted sequence. Numerous studies lacked sufficient data for calculating images resolution and only a few studies reported the acquired voxel volume, making it impossible for others to reproduce the protocol/images. Only a minority of the included papers assessed reliability tests and none of the studies documented whether the use of whole-body MRI affected mortality and/or morbidity. Our systematic review confirms significant variability of technique and the lack of proven validity of MRI findings. The information could potentially be used to boost attempts towards standardization of technique, reporting and guidelines development.
Topics: Adolescent; Child; Humans; Magnetic Resonance Imaging; Neoplasms; Osteomyelitis; Reproducibility of Results; Whole Body Imaging
PubMed: 32588094
DOI: 10.1007/s00247-020-04735-9