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1.
Gastroenterology ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39097199
3.
Int J Mol Sci ; 25(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39125864

RESUMO

The potential role of the transient receptor potential Vanilloid 1 (TRPV1) non-selective cation channel in gastric carcinogenesis remains unclear. The main objective of this study was to evaluate TRPV1 expression in gastric cancer (GC) and precursor lesions compared with controls. Patient inclusion was based on a retrospective review of pathology records. Patients were subdivided into five groups: Helicobacter pylori (H. pylori)-associated gastritis with gastric intestinal metaplasia (GIM) (n = 12), chronic atrophic gastritis (CAG) with GIM (n = 13), H. pylori-associated gastritis without GIM (n = 19), GC (n = 6) and controls (n = 5). TRPV1 expression was determined with immunohistochemistry and was significantly higher in patients with H. pylori-associated gastritis compared with controls (p = 0.002). TRPV1 expression was even higher in the presence of GIM compared with patients without GIM and controls (p < 0.001). There was a complete loss of TRPV1 expression in patients with GC. TRPV1 expression seems to contribute to gastric-mucosal inflammation and precursors of GC, which significantly increases in cancer precursor lesions but is completely lost in GC. These findings suggest TRPV1 expression to be a potential marker for precancerous conditions and a target for individualized treatment. Longitudinal studies are necessary to further address the role of TRPV1 in gastric carcinogenesis.


Assuntos
Infecções por Helicobacter , Neoplasias Gástricas , Canais de Cátion TRPV , Humanos , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/complicações , Infecções por Helicobacter/patologia , Carcinogênese/metabolismo , Carcinogênese/patologia , Estudos Retrospectivos , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Helicobacter pylori/patogenicidade , Metaplasia/metabolismo , Metaplasia/patologia , Gastrite/metabolismo , Gastrite/patologia , Gastrite/microbiologia , Adulto , Imuno-Histoquímica , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Gastrite Atrófica/metabolismo , Gastrite Atrófica/patologia
4.
AJOG Glob Rep ; 4(3): 100369, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39040659

RESUMO

Endometriosis is an estrogen-dependent chronic disease characterized by the presence of endometriumlike tissue outside the uterus and is often associated with symptoms, such as dysmenorrhea, dysuria, dyschezia, chronic pelvic pain, and infertility. Moreover, women diagnosed with endometriosis can report gastrointestinal symptoms, including bloating, constipation or diarrhea, and abdominal cramping, which can be associated with irritable bowel syndrome and can result in the misdiagnosis of endometriosis as irritable bowel syndrome at first. Treatment usually involves hormonal therapy, pain management, surgery, and/or assisted reproductive techniques in case of infertility. Nonetheless, these treatment methods can be insufficient for alleviating symptoms or can have unacceptable side effects, leading to noncompliance. Therefore, women often apply self-management strategies, including dietary interventions. One of the diets frequently suggested as a tool to manage endometriosis-related symptoms on social media and patient forums is a gluten-free diet. Although a gluten-free diet has been proven effective in managing nonceliac wheat sensitivity or celiac disease, its effectiveness in endometriosis remains uncertain. The Nurses' Health Study II found it unlikely that gluten intake was a strong factor in endometriosis etiology and symptomatology. To the best of our knowledge, the most frequently cited and sole published intervention study on the efficacy of a gluten-free diet for endometriosis has several important limiting factors, including the absence of a control group. In addition, gluten consumption is highly susceptible to a placebo effect and a nocebo effect, where women might experience symptom relief after eliminating gluten and return of symptoms after they consume gluten again, solely because they believe that gluten is bad for them. Despite the inverse association between body mass index and endometriosis and between a gluten-free diet and increased body mass index, this is an association, and no causality was proven. In addition, other factors should be taken into consideration. Of note, a gluten-free diet is expensive, has limited availability, and has a significant effect on quality of life. Moreover, without proper dietary guidance, it may adversely affect the gastrointestinal microbiome. Therefore, scientifically substantiated advice regarding the use of a gluten-free diet for endometriosis-related symptoms is currently not available, and a gluten-free diet should be discouraged unless there is an additional diagnosis of nonceliac wheat sensitivity or celiac disease.

5.
Colorectal Dis ; 26(8): 1505-1514, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923161

RESUMO

AIM: Faecal incontinence (FI) is a prevalent issue which can have a detrimental impact on the patient's quality of life. Current international guidelines lack strong treatment recommendations due to few studies in the field, in combination with the heterogeneity in outcome reporting. To address this, a core outcome set (COS) is proposed to standardize outcome reporting in FI studies, facilitating meta-analyses and enhancing therapeutic recommendations. Through several steps outlined by COMET 'what' to measure will be determined prior to determining 'how' to measure these outcomes. This systematic review aims to identify 'what' outcomes have been used in FI intervention studies so far in adult patients as a starting phase for the development of a future COS for FI. METHOD: Medline, Embase and the Cochrane library were searched to identify all outcomes reported in comparative effectiveness trials assessing one or more treatment option in adult patients suffering from FI. The outcomes were categorized according to the Core Outcome Measurement in Effectiveness Trials (COMET) taxonomy to standardize outcome terminology, assess completeness, and inform subsequent steps in COS development. RESULTS: A total of 109 studies were included, which revealed 51 unique outcomes classified into 38 domains within four core areas. On average four outcomes were reported per study (range 1-11). The most commonly reported outcomes were "severity of FI" (83%), "quality of life" (64%), "number of FI episodes" (40%), "anorectal motor function" (39%), and "frequency of bowel movements" (16%). CONCLUSION: This systematic review offers an overview of outcomes reported in FI studies, highlighting the heterogeneity between studies. This heterogeneity emphasizes the need for standardizing outcome reporting which can be established through the creation of a COS.


Assuntos
Incontinência Fecal , Qualidade de Vida , Incontinência Fecal/terapia , Humanos , Avaliação de Resultados em Cuidados de Saúde/métodos , Resultado do Tratamento , Feminino , Adulto , Masculino
9.
Aliment Pharmacol Ther ; 59(12): 1470-1488, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38590140

RESUMO

BACKGROUND: Persistent gastrointestinal symptoms are prevalent in adult patients with inflammatory bowel disease (IBD), even when endoscopic remission is reached. These symptoms can have profound negative effects on the quality of life of affected patients and can be difficult to treat. They may be caused by IBD-related complications or comorbid disorders, but they can also be explained by irritable bowel syndrome (IBS)-like symptoms. AIMS: To provide a practical step-by-step guide to diagnose and treat persistent gastrointestinal symptoms in patients with IBD in remission via a personalised approach. METHODS: We scrutinised relevant literature on causes, diagnostics and treatment of persistent gastrointestinal symptoms (abdominal pain or discomfort, bloating, abdominal distension, diarrhoea, constipation and faecal incontinence) in patients with IBD in remission. RESULTS: A graphical practical guide for several steps in diagnosing, identifying potential triggers and adequate treatment of persistent gastrointestinal symptoms in IBD in remission is provided based on supporting literature. The first part of this review focuses on the diagnostic and treatment approaches for potential IBD-related complications and comorbidities. The second part describes the approach to IBS-like symptoms in IBD in remission. CONCLUSIONS: Persistent gastrointestinal symptoms in IBD in remission can be traced back to potential pathophysiological mechanisms in individual patients and can be treated adequately. For both IBD-related complications and comorbidities and IBS-like symptoms in IBD in remission, pharmacological, dietary, lifestyle or psychological treatments can be effective. A systematic and personalised approach is required to reduce the burden for patients, healthcare systems, and society.


Assuntos
Doenças Inflamatórias Intestinais , Qualidade de Vida , Indução de Remissão , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/fisiopatologia , Gastroenteropatias/terapia , Gastroenteropatias/etiologia , Gastroenteropatias/fisiopatologia , Síndrome do Intestino Irritável/terapia , Síndrome do Intestino Irritável/fisiopatologia , Síndrome do Intestino Irritável/diagnóstico , Adulto
11.
Am J Clin Nutr ; 119(4): 896-907, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38373694

RESUMO

BACKGROUND: Many individuals reduce their bread intake because they believe wheat causes their gastrointestinal (GI) symptoms. Different wheat species and processing methods may affect these responses. OBJECTIVES: We investigated the effects of 6 different bread types (prepared from 3 wheat species and 2 fermentation conditions) on GI symptoms in individuals with self-reported noncoeliac wheat sensitivity (NCWS). METHODS: Two parallel, randomized, double-blind, crossover, multicenter studies were conducted. NCWS individuals, in whom coeliac disease and wheat allergy were ruled out, received 5 slices of yeast fermented (YF) (study A, n = 20) or sourdough fermented (SF) (study B, n = 20) bread made of bread wheat, spelt, or emmer in a randomized order on 3 separate test days. Each test day was preceded by a run-in period of 3 d of a symptom-free diet and separated by a wash-out period of ≥7 d. GI symptoms were evaluated by change in symptom score (test day minus average of the 3-d run-in period) on a 0-100 mm visual analogue scale (ΔVAS), comparing medians using the Friedman test. Responders were defined as an increase in ΔVAS of ≥15 mm for overall GI symptoms, abdominal discomfort, abdominal pain, bloating, and/or flatulence. RESULTS: GI symptoms did not differ significantly between breads of different grains [YF bread wheat median ΔVAS 10.4 mm (IQR 0.0-17.8 mm), spelt 4.9 mm (-7.6 to 9.4 mm), emmer 11.0 mm (0.0-21.3 mm), P = 0.267; SF bread wheat 10.5 mm (-3.1 to 31.5 mm), spelt 11.3 mm (0.0-15.3 mm), emmer 4.0 mm (-2.9 to 9.3 mm), P = 0.144]. The number of responders was also comparable for both YF (6 to wheat, 5 to spelt, and 7 to emmer, P = 0.761) and SF breads (9 to wheat, 7 to spelt, and 8 to emmer, P = 0.761). CONCLUSIONS: The majority of NCWS individuals experienced some GI symptoms for ≥1 of the breads, but on a group level, no differences were found between different grains for either YF or SF breads. CLINICAL TRIAL REGISTRY: clinicaltrials.gov, NCT04084470 (https://classic. CLINICALTRIALS: gov/ct2/show/NCT04084470).


Assuntos
Gastroenteropatias , Hipersensibilidade a Trigo , Humanos , Pão , Dieta , Fermentação
12.
Artigo em Inglês | MEDLINE | ID: mdl-38199302
13.
Am J Gastroenterol ; 119(1): 155-164, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37737676

RESUMO

INTRODUCTION: Sleep quality may affect symptom experience in irritable bowel syndrome (IBS). Our aim was to investigate the relationship between sleep quality and gastrointestinal (GI) symptoms using actigraphy and the experience sampling method. METHODS: Patients with IBS were recruited from a tertiary Neurogastroenterology clinic and the community. GI symptoms and mood were recorded on a smartphone application, 10 times per day, over 7 consecutive days. Subjective sleep quality was recorded every morning to reflect the night before. Objective measures of sleep quality were estimated from wrist-worn actigraphy. Cross-lagged structural equation models were built to assess the directionality of sleep-symptom relationships over time. RESULTS: Eighty patients with IBS completed the study (mean age: 37 years [range 20-68], 89% female, 78% community). Approximately 66% had a Pittsburgh Sleep Quality Index score ≥ 8, indicating a clinically significant sleep disturbance. Approximately 82% (95% CI: 72-90) screened positive for a sleep disorder, most commonly insomnia. In cross-lagged analysis, poor subjective sleep quality predicted next-day abdominal pain (0.036 < P < 0.040) and lower GI symptoms (0.030 < P < 0.032), but not vice versa. No significant relationship with GI symptoms was found for any objective sleep measure using actigraphy. DISCUSSION: Poor subjective sleep quality was associated with higher next-day lower GI symptom levels, but not vice versa. Objective sleep measures did not predict next-day abdominal symptoms, potentially supporting the conclusion that it is the perception of sleep quality that is most influential. This study may be used to guide future research into the effect of sleep interventions on GI symptoms.


Assuntos
Gastroenteropatias , Síndrome do Intestino Irritável , Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/diagnóstico , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/etiologia , Qualidade do Sono , Avaliação Momentânea Ecológica , Sono , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/etiologia
14.
Lancet Gastroenterol Hepatol ; 9(2): 110-123, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38040019

RESUMO

BACKGROUND: Many individuals without coeliac disease or wheat allergy reduce their gluten intake because they believe that gluten causes their gastrointestinal symptoms. Symptoms could be affected by negative expectancy. Therefore, we aimed to investigate the effects of expectancy versus actual gluten intake on symptoms in people with non-coeliac gluten sensitivity (NCGS). METHODS: This randomised, double-blind, placebo-controlled, international, multicentre study was done at the University of Leeds (Leeds, UK), Maastricht University (Maastricht, the Netherlands), and Wageningen University and Research (Wageningen, the Netherlands). People aged 18-70 years with self-reported NCGS (ie, gastrointestinal symptoms within 8 h of gluten consumption) without coeliac disease and wheat allergy were recruited. Participants had to follow a gluten-free or gluten-restricted diet for at least 1 week before (and throughout) study participation and had to be asymptomatic or mildly symptomatic (overall gastrointestinal symptom score ≤30 mm on the Visual Analogue Scale [VAS]) while on the diet. Participants were randomly assigned (1:1:1:1; blocks of eight; stratified by site and gender) to one of four groups based on the expectation to consume gluten-containing (E+) or gluten-free (E-) oat bread for breakfast and lunch (two slices each) and actual intake of gluten-containing (G+) or gluten-free (G-) oat bread. Participants, investigators, and those assessing outcomes were masked to the actual gluten assignment, and participants were also masked to the expectancy part of the study. The primary outcome was overall gastrointestinal symptom score on the VAS, which was measured at and corrected for baseline (before breakfast) and hourly for 8 h, with lunch served after 4 h, and analysed per-protocol. Safety analysis included all participants incorporated in the per-protocol analysis. The study is registered at ClinicalTrials.gov, NCT05779358, and has ended. FINDINGS: Between Oct 19, 2018, and Feb 14, 2022, 165 people were screened and 84 were randomly assigned to E+G+ (n=21), E+G- (n=21), E-G+ (n=20), or E-G- (n=22). One person in the E+G+ group was excluded due to not following test day instructions, leaving 83 participants in the per-protocol analysis. Median age was 27·0 years (IQR 21·0-45·0), 71 (86%) of 83 people were women, and 12 (14%) were men. Mean overall gastrointestinal symptom score was significantly higher for E+G+ (16·6 mm [95% CI 13·1 to 20·0]) than for E-G+ (6·9 mm [3·5 to 10·4]; difference 9·6 mm [95% CI 3·0 to 16·2], p=0·0010) and E-G- (7·4 mm [4·2 to 10·7]; difference 9·1 mm [2·7 to 15·6], p=0·0016), but not for E+G- (11·7 mm [8·3 to 15·1]; difference 4·9 mm [-1·7 to 11·5], p=0·28). There was no difference between E+G- and E-G+ (difference 4·7 mm [-1·8 to 11·3], p=0·33), E+G- and E-G- (difference 4·2 mm [-2·2 to 10·7], p=0·47), and E-G+ and E-G- (difference -0·5 mm [-7·0 to 5·9], p=1·0). Adverse events were reported by two participants in the E+G- group (itching jaw [n=1]; feeling lightheaded and stomach rumbling [n=1]) and one participant in the E-G+ group (vomiting). INTERPRETATION: The combination of expectancy and actual gluten intake had the largest effect on gastrointestinal symptoms, reflecting a nocebo effect, although an additional effect of gluten cannot be ruled out. Our results necessitate further research into the possible involvement of the gut-brain interaction in NCGS. FUNDING: Government of the Netherlands Topsector Agri & Food Top Consortium for Knowledge and Innovation, AB Mauri Global Bakery Ingredients, Baking Industry Research Trust, Borgesius-Albert Heijn, CSM Innovation Centre, the International Maize and Wheat Improvement Center (CIMMYT), DSM Food Specialties, Fazer, Healthgrain Forum, the International Association for Cereal Science and Technology, the International Wheat Gluten Association, Lantmännen, Mondelez International, Nederlands Bakkerij Centrum, Nutrition & Santé, Puratos, Rademaker, Sonneveld Group, and Zeelandia HJ Doeleman.


Assuntos
Doença Celíaca , Hipersensibilidade a Trigo , Masculino , Humanos , Feminino , Adulto , Doença Celíaca/diagnóstico , Hipersensibilidade a Trigo/diagnóstico , Glutens/efeitos adversos , Dieta Livre de Glúten , Método Duplo-Cego
15.
JMIR Med Inform ; 11: e44639, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015588

RESUMO

BACKGROUND: Information overflow, a common problem in the present clinical environment, can be mitigated by summarizing clinical data. Although there are several solutions for clinical summarization, there is a lack of a complete overview of the research relevant to this field. OBJECTIVE: This study aims to identify state-of-the-art solutions for clinical summarization, to analyze their capabilities, and to identify their properties. METHODS: A scoping review of articles published between 2005 and 2022 was conducted. With a clinical focus, PubMed and Web of Science were queried to find an initial set of reports, later extended by articles found through a chain of citations. The included reports were analyzed to answer the questions of where, what, and how medical information is summarized; whether summarization conserves temporality, uncertainty, and medical pertinence; and how the propositions are evaluated and deployed. To answer how information is summarized, methods were compared through a new framework "collect-synthesize-communicate" referring to information gathering from data, its synthesis, and communication to the end user. RESULTS: Overall, 128 articles were included, representing various medical fields. Exclusively structured data were used as input in 46.1% (59/128) of papers, text in 41.4% (53/128) of articles, and both in 10.2% (13/128) of papers. Using the proposed framework, 42.2% (54/128) of the records contributed to information collection, 27.3% (35/128) contributed to information synthesis, and 46.1% (59/128) presented solutions for summary communication. Numerous summarization approaches have been presented, including extractive (n=13) and abstractive summarization (n=19); topic modeling (n=5); summary specification (n=11); concept and relation extraction (n=30); visual design considerations (n=59); and complete pipelines (n=7) using information extraction, synthesis, and communication. Graphical displays (n=53), short texts (n=41), static reports (n=7), and problem-oriented views (n=7) were the most common types in terms of summary communication. Although temporality and uncertainty information were usually not conserved in most studies (74/128, 57.8% and 113/128, 88.3%, respectively), some studies presented solutions to treat this information. Overall, 115 (89.8%) articles showed results of an evaluation, and methods included evaluations with human participants (median 15, IQR 24 participants): measurements in experiments with human participants (n=31), real situations (n=8), and usability studies (n=28). Methods without human involvement included intrinsic evaluation (n=24), performance on a proxy (n=10), or domain-specific tasks (n=11). Overall, 11 (8.6%) reports described a system deployed in clinical settings. CONCLUSIONS: The scientific literature contains many propositions for summarizing patient information but reports very few comparisons of these proposals. This work proposes to compare these algorithms through how they conserve essential aspects of clinical information and through the "collect-synthesize-communicate" framework. We found that current propositions usually address these 3 steps only partially. Moreover, they conserve and use temporality, uncertainty, and pertinent medical aspects to varying extents, and solutions are often preliminary.

17.
Am J Gastroenterol ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37791610

RESUMO

INTRODUCTION: Irritable bowel syndrome (IBS) has a major impact on emotional, social, and professional life. This study aimed to evaluate general life satisfaction, a subjective measure of well-being, in IBS patients, and to determine which factors are associated with higher life satisfaction. METHODS: IBS patients (n = 195, mean age 51.4 ± 16.5 years, 73.8% female) recruited from primary and secondary/tertiary care completed questionnaires regarding gastrointestinal symptoms, quality of life, psychological factors, and life satisfaction (Satisfaction With Life Scale, 5 items, range 5-35). A finite mixture model analysis was performed to identify latent classes. Multivariable linear regression was used to identify variables associated with life satisfaction. RESULTS: Overall, 71.3% of the patients were satisfied about their life (Satisfaction With Life Scale-score ≥21). Three latent subgroups could be identified with significantly higher life satisfaction in the subgroup with higher mental quality of life, fewer anxiety and depressive symptoms, lower gastrointestinal specific anxiety, and lower gastrointestinal symptom severity, compared with the other 2 groups. Multivariable linear regression showed that higher physical quality of life (B0.168, P < 0.001) and higher mental quality of life (B0.199, P < 0.001) were associated with higher life satisfaction. Using multivariable regression, no significant association was found between gastrointestinal symptom severity and life satisfaction. DISCUSSION: Higher physical and mental quality of life, but not gastrointestinal symptom severity, were independently associated with higher general life satisfaction in IBS. These findings reinforce the clinical need in IBS treatment to focus on the full extent of the disorder and not merely on gastrointestinal symptom improvement. ClinicalTrials.gov Identifier: NCT00775060.

19.
Front Nutr ; 10: 1166929, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731404

RESUMO

Endometriosis is characterized by the presence of endometrium-like tissue outside the uterus. The etiology remains largely unknown. Despite adequate treatment, patients can still experience symptoms or side effects resulting in therapy incompliance and in self-management strategies such as dietary measures is increasing. A gluten free diet is thought to be contributory in reducing endometriosis-related pain, thereby optimizing quality of life. However, data is conflicting and currently provides no evidence for causality. This narrative review aims to put the effect of dietary self-management strategies on endometriosis in a balanced perspective, especially the effect of gluten and a gluten free diet. Several studies have found a strong overlap in symptoms, metabolic and immune responses associated with endometriosis and those associated with celiac disease, ulcerative colitis, Crohn's disease, irritable bowel syndrome and non-celiac wheat sensitivity. However, it remains unclear whether these diseases and/or disorders are causal to an increased risk of endometriosis. Some studies have found a positive effect on the risk of endometriosis, endometriosis-related symptoms and quality of life (QoL) when women either avoided certain nutrients or foods, or applied a specific nutrient supplementation. This includes the avoidance of red meat, an increasing intake of foods rich in anti-oxidants, omega-3, micronutrients and dietary fibers (e.g., fruit, vegetables) and the appliance of a gluten free diet. However, data from the available studies were generally graded of low quality and it was noted that placebo and/or nocebo effects influenced the reported positive effects. In addition, such effects were no longer seen when adjusting for confounders such as overweight, when a translation was made from in vitro to in vivo, or when the nutrients were not supplemented as isolated sources but as part of a mixed daily diet. Finally, some studies showed that long-term adherence to a gluten free diet is often associated with an impaired diet quality and nutrient intake, leading to negative health outcomes and reduced QoL. Concluding, scientific evidence on the efficacy of dietary interventions on well-defined clinical endpoints of endometriosis is lacking and recommending a gluten free diet to women solely diagnosed with endometriosis should therefore not be advised.

20.
Neuroimage ; 280: 120361, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37669723

RESUMO

In functional magnetic resonance imaging (fMRI) of the brain the measured signal is corrupted by several (e.g. physiological, motion, and thermal) noise sources and depends on the image acquisition. Imaging at ultrahigh field strength is becoming increasingly popular as it offers increased spatial accuracy. The latter is of particular benefit in brainstem neuroimaging given the small cross-sectional area of most nuclei. However, physiological noise scales with field strength in fMRI acquisitions. Although this problem is in part solved by decreasing voxel size, it is clear that adequate physiological denoising is of utmost importance in brainstem-focused fMRI experiments. Multi-echo sequences have been reported to facilitate highly effective denoising through TE-dependence of Blood Oxygen Level Dependent (BOLD) signals, in a denoising method referred to as multi-echo independent component analysis (ME-ICA). It has not been explored previously how ME-ICA compares to other data-driven denoising approaches at ultrahigh field strength. In the current study, we compared the efficacy of several denoising methods, including anatomical component based correction (aCompCor), Automatic Removal of Motion Artifacts (ICA-AROMA) aggressive and non-aggressive options, ME-ICA, and a combination of ME-ICA and aCompCor. We assessed several data quality metrics, including temporal signal-to-noise ratio (tSNR), delta variation signal (DVARS), spectral density of the global signal, functional connectivity and Shannon spectral entropy. Moreover, we looked at the ability of each method to uncouple the global signal and respiration. In line with previous reports at lower field strengths, we demonstrate that after applying ME-ICA, the data is best post-processed in order to remove spatially diffuse noise with a method such as aCompCor. Our findings indicate that ME-ICA combined with aCompCor and the aggressive option of ICA-AROMA are highly effective denoising approaches for multi-echo data acquired at 7T. ME-ICA combined with aCompCor potentially preserves more signal-of-interest as compared to the aggressive option of ICA-AROMA.


Assuntos
Imageamento por Ressonância Magnética , Neuroimagem , Humanos , Agressão , Artefatos , Benchmarking
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