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1.
Acta Neurol Scand ; 2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32416627

RESUMO

BACKGROUND: Optical coherence tomography (OCT) could be complementary to magnetic resonance imaging (MRI) of the brain in monitoring course of multiple sclerosis (MS) and clinically isolated syndrome (CIS). Thinning of neurons in ganglion cell-inner plexiform layer (GCIPL) measured by OCT is assumed to be associated with brain atrophy. OBJECTIVES: To evaluate association of GCIPL with brain parameters detected by quantitative MRI (qMRI) and MR-spectroscopy (MRS) in early MS and CIS. METHODS: 17 newly diagnosed MS and 18 CIS patients were prospectively included. The patients were assessed at baseline as well as at 1 year follow-up by OCT, qMRI and MRS. Brain parenchymal and myelin volumes (BPV, MYV respectively) and the corresponding fractions (BPF, MYF) were measured with qMRI. Metabolites including myo-inositol (myo-Ins) were measured in the normal-appearing white matter (NAWM) using MRS. T-tests and ANOVA were used to analyze group differences, and linear regression models to evaluate association of GCIPL with BPV, MYV and myo-Ins after correlation analysis. RESULTS: Disease activity reflected by lesions on MRI and presence of CSF oligoclonal IgG bands were more prominent in MS compared to CIS. GCIPL, BPV, MYV, BPF and MYF were reduced, while concentration of myo-Ins was increased in MS compared to CIS. Follow-up showed consistency of thinner GCIPL in MS compared to CIS. GCIPL thinning correlated with reduced BPV and MYV (p<0.05 for both), but with increased myo-Ins (p<0.01). CONCLUSIONS: Significant GCIPL thinning occurs in early MS, and is associated with enhanced brain inflammation and atrophy.

2.
Sci Rep ; 9(1): 13590, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31537890

RESUMO

Altered neural mechanisms are well-acknowledged in irritable bowel syndrome (IBS), a disorder of brain-gut-communication highly comorbid with anxiety and depression. As a key hub in corticolimbic inhibition, medial prefrontal cortex (mPFC) may be involved in disturbed emotion regulation in IBS. However, aberrant mPFC excitatory and inhibitory neurotransmission potentially contributing to psychological symptoms in IBS remains unknown. Using quantitative magnetic resonance spectroscopy (qMRS), we compared mPFC glutamate + glutamine (Glx) and γ-aminobutyric acid (GABA+) concentrations in 64 women with IBS and 32 age-matched healthy women (HCs) and investigated their association with anxiety and depression in correlational and subgroup analyses. Applying functional magnetic resonance imaging (fMRI), we explored whether altered neurotransmission was paralleled by aberrant mPFC resting-state functional connectivity (FC). IBS patients did not differ from HCs with respect to mPFC GABA+ or Glx levels. Anxiety was positively associated with mPFC GABA+ concentrations in IBS, whereas Glx was unrelated to psychological or gastrointestinal symptoms. Subgroup comparisons of patients with high or low anxiety symptom severity and HCs revealed increased GABA+ in patients with high symptom severity, and lower mPFC FC with adjacent anterior cingulate cortex (ACC), a crucial region of emotion modulation. Our findings provide novel evidence that altered prefrontal inhibitory neurotransmission may be linked to anxiety in IBS.

3.
J Pain Res ; 12: 1743-1755, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213886

RESUMO

Purpose: The remodeling of functional neuronal connectivity in chronic widespread pain (CWP) patients remains largely unexplored. This study aimed to investigate functional connectivity in CWP patients in brain networks related to chronic pain for changes related to pain sensitivity, psychological strain, and experienced pain. Patients and methods: Functional connectivity strength of the default mode network (DMN) and the salience network (SN) was assessed with functional magnetic resonance imaging. Between-group differences were investigated with an independent component analysis for altered connectivity within the whole DMN and SN. Then, changes in connectivity between nodes of the DMN and SN were investigated with the use of a seed-target analysis in relation to the covariates clinical pain intensity, pressure pain sensitivity, psychological strain, and as an effect of experienced experimental cuff-pressure pain. Results: CWP patients showed decreased connectivity in the inferior posterior cingulate cortex (PCC) in the DMN and increased connectivity in the left anterior insula/superior temporal gyrus in the SN when compared to controls. Moreover, higher pain sensitivity in CWP when compared to controls was related to increased connectivity within the SN (between left and right insula) and between SN and DMN (between right insula and left lateral parietal cortex). Conclusion: This study shows that connectivity within the DMN was decreased and connectivity within the SN was increased for CWP. Furthermore, we present a novel finding of interaction of pain sensitivity with SN and DMN-SN functional connectivity in CWP.

4.
PLoS Comput Biol ; 15(6): e1007157, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31237870

RESUMO

Estimation of liver function is important to monitor progression of chronic liver disease (CLD). A promising method is magnetic resonance imaging (MRI) combined with gadoxetate, a liver-specific contrast agent. For this method, we have previously developed a model for an average healthy human. Herein, we extended this model, by combining it with a patient-specific non-linear mixed-effects modeling framework. We validated the model by recruiting 100 patients with CLD of varying severity and etiologies. The model explained all MRI data and adequately predicted both timepoints saved for validation and gadoxetate concentrations in both plasma and biopsies. The validated model provides a new and deeper look into how the mechanisms of liver function vary across a wide variety of liver diseases. The basic mechanisms remain the same, but increasing fibrosis reduces uptake and increases excretion of gadoxetate. These mechanisms are shared across many liver functions and can now be estimated from standard clinical images.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Fígado/metabolismo , Imagem por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Gadolínio DTPA/farmacocinética , Humanos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/metabolismo , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Reprodutibilidade dos Testes , Adulto Jovem
5.
Pain ; 160(9): 2004-2012, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31045748

RESUMO

Irritable bowel syndrome (IBS) is a visceral pain condition with psychological comorbidity. Brain imaging studies in IBS demonstrate altered function in anterior insula (aINS), a key hub for integration of interoceptive, affective, and cognitive processes. However, alterations in aINS excitatory and inhibitory neurotransmission as putative biochemical underpinnings of these functional changes remain elusive. Using quantitative magnetic resonance spectroscopy, we compared women with IBS and healthy women (healthy controls [HC]) with respect to aINS glutamate + glutamine (Glx) and γ-aminobutyric acid (GABA+) concentrations and addressed possible associations with symptoms. Thirty-nine women with IBS and 21 HC underwent quantitative magnetic resonance spectroscopy of bilateral aINS to assess Glx and GABA+ concentrations. Questionnaire data from all participants and prospective symptom-diary data from patients were obtained for regression analyses of neurotransmitter concentrations with IBS-related and psychological parameters. Concentrations of Glx were lower in IBS compared with HC (left aINS P < 0.05, right aINS P < 0.001), whereas no group differences were detected for GABA+ concentrations. Lower right-lateralized Glx concentrations in patients were substantially predicted by longer pain duration, while less frequent use of adaptive pain-coping predicted lower Glx in left aINS. Our findings provide first evidence for reduced excitatory but unaltered inhibitory neurotransmitter levels in aINS in IBS. The results also indicate a functional lateralization of aINS with a stronger involvement of the right hemisphere in perception of abdominal pain and of the left aINS in cognitive pain regulation. Our findings suggest that glutaminergic deficiency may play a role in pain processing in IBS.

6.
J Magn Reson Imaging ; 50(1): 325-333, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30637926

RESUMO

BACKGROUND: Liver iron content (LIC) in chronic liver disease (CLD) is currently determined by performing an invasive liver biopsy. MRI using R2* relaxometry is a noninvasive alternative for estimating LIC. Fat accumulation in the liver, or proton density fat fraction (PDFF), may be a possible confounder of R2* measurements. Previous studies of the effect of PDFF on R2* have not used quantitative LIC measurement. PURPOSE: To assess the associations between R2*, LIC, PDFF, and liver histology in patients with suspected CLD. STUDY TYPE: Prospective. POPULATION: Eighty-one patients with suspected CLD. FIELD STRENGTH/SEQUENCE: 1.5 T. Multiecho turbo field echo to quantify R2*. PRESS MRS to quantify PDFF. ASSESSMENT: Each patient underwent an MR examination, followed by two needle biopsies immediately following the MR examination. The first biopsy was used for conventional histological assessment of LIC, whereas the second biopsy was used to quantitatively measure LIC using mass spectrometry. R2* was correlated with both LIC and PDFF. A correction for the influence of fat on R2* was calculated. STATISTICAL TESTS: Pearson correlation, linear regression, and area under the receiver operating curve. RESULTS: There was a positive linear correlation between R2* and PDFF (R = 0.69), after removing data from patients with elevated iron levels, as defined by LIC. R2*, corrected for PDFF, was the best method for identifying patients with elevated iron levels, with a correlation of R = 0.87 and a sensitivity and specificity of 87.5% and 98.6%, respectively. DATA CONCLUSION: PDFF increases R2*. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:325-333.

7.
Surg Obes Relat Dis ; 15(1): 1-7, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30497847

RESUMO

BACKGROUND: Sleeve gastrectomy (SG) is the most popular bariatric procedure in the United States. Although standardized, variation exists in how the staple line is managed. Robotic approaches to SG (RSG) are increasing, though benefits compared with the conventional laparoscopic approach (LSG) remain controversial. OBJECTIVE: Evaluate the safety of RSG versus LSG using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry, controlling for variation in staple-line management. SETTING: University health network, United States. METHODS: SG cases from January 1 to December 31, 2016, in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry were included. Demographic characteristics and 30-day outcomes were analyzed with separate Mann-Whitney rank sums tests, χ2 tests, or Fisher's exact tests, with P < .05 denoting statistical significance. Multivariate regression analysis was performed to control for method of staple-line treatment. RESULTS: Of the 107,726 patients who underwent SG, 7385 were RSG. Treatment of the staple line was associated with a significantly lower rate of bleeding, with odds ratios of .69 and .58 for staple-line reinforcement alone and staple-line reinforcement plus oversewing, respectively. Multivariate analysis revealed RSG had a higher rate of organ space infection than LSG (odds ratio 2.07). Otherwise, RSG did not significantly differ from LSG save for a longer median operative time (89 versus 63 min, respectively, P < .0001). CONCLUSIONS: RSG is a growing alternative to the conventional laparoscopic approach. According to the 2016 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database, the RSG carries a higher risk of organ space infection. The reasons behind this finding require further study.


Assuntos
Cirurgia Bariátrica , Gastrectomia , Laparoscopia , Obesidade Mórbida/cirurgia , Procedimentos Cirúrgicos Robóticos , Adulto , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/mortalidade , Cirurgia Bariátrica/estatística & dados numéricos , Feminino , Gastrectomia/efeitos adversos , Gastrectomia/mortalidade , Gastrectomia/estatística & dados numéricos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/mortalidade , Laparoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/mortalidade , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos
8.
Magn Reson Med ; 81(4): 2223-2237, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30417930

RESUMO

PURPOSE: To develop a method for retrospective artifact elimination of MRS data. This retrospective method was based on an approach that combines jackknife analyses with the correlation of spectral windows, and therefore termed "JKC." METHODS: Twelve healthy volunteers performed 3 separate measurement protocols using a 3T MR system. One protocol consisted of 2 cerebellar MEGA-PRESS measurements: 1 reference and 1 measurement including head movements. One-third of the artifact-influenced datasets were treated as training data for the implementation the JKC method, and the rest were used for validation. RESULTS: The implemented JKC method correctly characterized most of the validation data. Additionally, after elimination of the detected artifacts, the resulting concentrations were much closer to those computed for the reference datasets. Moreover, when the JKC method was applied to the reference data, the estimated concentrations were not affected, compared with standard averaging. CONCLUSION: The implemented JKC method can be applied without any extra cost to MRS data, regardless of whether the dataset has been contaminated by artifacts. Furthermore, the results indicate that the JKC method could be used as a quality control of a dataset, or as an indication of whether a shift in voxel placement has occurred during the measurement.

9.
Updates Surg ; 71(3): 445-450, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30467789

RESUMO

The laparoscopic adjustable gastric band (AGB) has fallen out of favor due to poor long-term weight loss and frequent complications. Many patients stand to benefit from elective conversion of AGB to more durable procedures such as sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB). Whether it is safer to perform this conversion in one or two stages, however, remains controversial. We performed an IRB-approved review of prospectively collected data from all one-stage band conversions performed at our institution from January 2012 to December 2017. Patients were separated into two groups: those who underwent conversion to either a RYGB or SG. Demographics, indications, and outcomes of each group were compared using Fisher's exact test, Mann-Whitney rank sums, and chi-squared tests. Outcomes were recorded within a 1-year follow-up period and compared to published outcomes for one-stage band conversions. Thirty-eight patients were included for analysis. Average age and BMI were was 50.8 years and 41.1 kg/m2, respectively. The average operative time (164 min, 105-258 min) and length of stay (2.2 days, 1-5 days) did not differ between indication and procedure performed. Overall, early (< 30 day) and late (> 30 day) major complication rates were 7.9% and 5.3%, respectively. There were no leaks and no deaths. Within a 1-year postoperative period, seven re-interventions were performed. Elective one-stage band conversion to RYGB or SG can be performed safely.


Assuntos
Gastroplastia/efeitos adversos , Reoperação/efeitos adversos , Feminino , Gastrectomia/métodos , Derivação Gástrica/métodos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Reoperação/métodos , Estudos Retrospectivos , Falha de Tratamento
10.
Surg Obes Relat Dis ; 14(9): 1240-1245, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30580769

RESUMO

BACKGROUND: The use of robotic platforms in performing laparoscopic Roux-en-Y gastric bypass (LRYGB) is increasing, though their safety compared with the conventional laparoscopic approach remains unclear. OBJECTIVE: The objective of this study was to evaluate perioperative data and 30-day outcomes of conventional and robot-assisted LRYGB using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry. SETTING: University health network, United States. METHODS: We reviewed all conventional and robot-assisted LRYGB cases entered between January 1 and December 31, 2016 in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry. Demographic characteristics and 30-day outcomes were analyzed based on separate Mann-Whitney rank sums tests, χ2, or Fisher's exact tests as appropriate, with P ≤ .05 denoting statistical significance with no adjustment for multiple testing. RESULTS: Of the 39,425 patients who underwent LRYGB, 2822 were robot-assisted. The robot-assisted approach required significantly more time (138 versus 108 min, P < .0001). Rates of organ space infection, bleeding, and other significant adverse events after the conventional and robot-assisted approaches were .3% versus .5% (P = .13), 1.1% versus .8% (P = .11), and 2.3% versus 2.3% (P = .96), respectively. There were also no significant differences in the rates of mortality, length of stay, reoperation, or readmission between the 2 groups. CONCLUSIONS: Robot-assisted LRYGB is an increasingly popular alternative to the conventional laparoscopic approach. According to the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database, the early safety of these 2 techniques is equal, although the robotic approach requires more operative time.


Assuntos
Cirurgia Bariátrica , Melhoria de Qualidade , Procedimentos Cirúrgicos Robóticos , Adulto , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/normas , Cirurgia Bariátrica/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/normas , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos
11.
J Neuroinflammation ; 15(1): 209, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-30021640

RESUMO

BACKGROUND: There is a need for clinically useful biomarkers of disease activity in clinically isolated syndrome (CIS) and relapsing remitting MS (RRMS). The aim of this study was to assess the correlation between neurofilament light chain (NFL) in cerebrospinal fluid (CSF) and serum and the relationship between NFL and other biomarkers, subsequent disease activity, and brain volume loss in CIS and RRMS. METHODS: A panel of neurodegenerative and neuroinflammatory markers were analyzed in repeated CSF samples from 41 patients with CIS or RRMS in a prospective longitudinal cohort study and from 22 healthy controls. NFL in serum was analyzed using a single-molecule array (Simoa) method. "No evidence of disease activity-3" (NEDA-3) status and brain volume (brain parenchymal fraction calculated using SyMRI®) were recorded during 4 years of follow-up. RESULTS: NFL levels in CSF and serum correlated significantly (all samples, n = 63, r 0.74, p < 0.001), but CSF-NFL showed an overall stronger association profile with NEDA-3 status, new T2 lesions, and brain volume loss. CSF-NFL was associated with both new T2 lesions and brain volume loss during follow-up, whereas CSF-CHI3L1 was associated mainly with brain volume loss and CXCL1, CXCL10, CXCL13, CCL22, and MMP-9 were associated mainly with new T2 lesions. CONCLUSIONS: Serum and CSF levels of NFL correlate, but CSF-NFL predicts and reflects disease activity better than S-NFL. CSF-NFL levels are associated with both new T2 lesions and brain volume loss. Our findings further add to the accumulating evidence that CSF-NFL is a clinically useful biomarker in CIS and RRMS and should be considered in the expanding NEDA concept. CSF-CXCL10 and CSF-CSF-CHI3L1 are potential markers of disease activity and brain volume loss, respectively.


Assuntos
Encéfalo/diagnóstico por imagem , Esclerose Múltipla , Proteínas de Neurofilamentos/sangue , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Adulto , Quimiocinas/sangue , Quimiocinas/líquido cefalorraquidiano , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imagem por Ressonância Magnética , Masculino , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos , Adulto Jovem
12.
Obes Surg ; 28(9): 2789-2795, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29679337

RESUMO

BACKGROUND: Revisional surgery is the fastest growing area in bariatric surgery, constituting 13.6% of all procedures performed as of 2015. This reflects a rising need to treat adverse sequelae of primary bariatric procedures. Despite the increase in revisions, their safety and efficacy remain controversial. The objective of this study is to review the experience of revisional bariatric surgery in our center and the relevant literature to date. METHODS: We performed an IRB-approved review of prospectively collected data from all patients undergoing revisional bariatric surgery between 2012 and 2015. Due to patient heterogeneity, we divided subjects into two groups: patients who underwent surgery for weight regain (WR) and those who underwent surgery to address refractory complications (RC) related to their primary bariatric procedure. Demographics, indications, and outcomes of each group were compared using Fisher's exact test, Mann-Whitney rank sums, and chi-square tests. We also divided WR patients based on their primary index procedure and analyzed them separately. RESULTS: We performed a total of 84 procedures over 4 years. Forty-three patients (53.6%) underwent surgery for WR and 41 (46.4%) for RC. The variety and distribution of primary bariatric procedures were gastric band (40%), gastric bypass (35.4%), sleeve gastrectomy (22%), and vertical banded gastroplasty (3.7%). The indications for revisional surgery due to RC included gastroesophageal reflux disease, internal hernia, gastro-gastric fistula, marginal ulcer, excess weight loss, and pain. Overall complication rate was 14.3% (three early, nine late); there was one leak. Five patients required a reoperation (5.9%; two early, three late). Excess weight loss varied from 31.5-79.1% 12 months after revision. CONCLUSION: Patients presenting to our center for revisional surgery do so for either WR or RC, most commonly following gastric banding. Revisional bariatric surgery can be performed with low complication rates and with acceptable 12-month weight loss, though not with the same safety as primary procedures.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Complicações Pós-Operatórias , Ganho de Peso , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/estatística & dados numéricos , Humanos , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/fisiopatologia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Perda de Peso
13.
Surg Obes Relat Dis ; 14(5): 545-551, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29551470

RESUMO

BACKGROUND: According to recent American Society for Metabolic and Bariatric Surgery estimates, sleeve gastrectomy (SG) is now the most commonly performed procedure in the United States (~53.8% of all bariatric procedures), followed by Roux-en-Y gastric bypass (RYGB; 23.1% of all procedures). OBJECTIVES: The objective of this study was to evaluate outcomes and safety of these 2 procedures in the first 30 days postoperatively using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry. SETTING: University health network, United States. METHODS: We reviewed all SG and RYGB cases entered between January 1 and December 31, 2015 in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry. Demographic characteristics and 30-day outcomes were analyzed based on separate Mann-Whitney rank sums tests, χ2, or Fisher's exact tests as appropriate, with P<.05 denoting statistical significance and no adjustment for multiple testing. RESULTS: A total of 141,646 patients were analyzed; 98,292 underwent SG and 43,354 underwent RYGB. Average age was 44.5 and 45.4 years for SG and RYGB, respectively. Preoperative body mass index was 45.1 and 46.1 for SG and RYGB, respectively. The 30-day mortality was .1% for SG and .2% for RYGB (P<.05). The incidence of unplanned intensive care unit admission after RYGB was twice as high compared with SG (1.3% versus .6%, respectively, P<.05). The incidence of at least 1 intervention or reoperation after RYGB was significantly higher compared with SG (2.8% and 2.5% for GB versus 1.2% and 1% for SG, P<.05). After RYGB, .4% of patients had a drain left in place at 30 days postoperatively versus .3% for SG (P<.05). The incidence of readmission was 2.8% for RYGB and 1.2% for SG (P<.05). CONCLUSIONS: The incidence of postoperative complications in the first 30 days after surgery is low for both RYGB and SG. However, SG seems to have a better safety profile in the first 30 days postoperatively compared with RYGB. These findings should be considered in the preoperative evaluation and counseling of bariatric patients. Long-term follow-up is needed to compare safety and efficacy of SG versus RYGB.


Assuntos
Cirurgia Bariátrica/normas , Gastrectomia/normas , Obesidade Mórbida/cirurgia , Acreditação , Adulto , Cirurgia Bariátrica/métodos , Feminino , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Derivação Gástrica/métodos , Derivação Gástrica/normas , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Melhoria de Qualidade , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos
14.
Brain Imaging Behav ; 12(2): 411-424, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28321606

RESUMO

The study investigated brain activity changes during performance of a verbal working memory task in a population of adolescents with narcolepsy. Seventeen narcolepsy patients and twenty healthy controls performed a verbal working memory task during simultaneous fMRI and EEG acquisition. All subjects also underwent MRS to measure GABA and Glutamate concentrations in the medial prefrontal cortex. Activation levels in the default mode network and left middle frontal gyrus were examined to investigate whether narcolepsy is characterized by an imbalance in cognitive resources. Significantly increased deactivation within the default mode network during task performance was observed for the narcolepsy patients for both the encoding and recognition phases of the task. No evidence for task performance deficits or reduced activation within the left middle frontal gyrus was noted for the narcolepsy patients. Correlation analyses between the spectroscopy and fMRI data indicated that deactivation of the anterior aspect of the default mode in narcolepsy patients correlated more with increased concentrations of Glutamate and decreased concentrations of GABA. In contrast, deactivation in the default mode was correlated with increased concentrations of GABA and decreased concentrations of Glutamate in controls. The results suggested that narcolepsy is not characterized by a deficit in working memory but rather an imbalance of cognitive resources in favor of monitoring and maintaining attention over actual task performance. This points towards dysregulation within the sustained attention system being the origin behind self-reported cognitive difficulties in narcolepsy.


Assuntos
Encéfalo/fisiopatologia , Cognição/fisiologia , Narcolepsia/fisiopatologia , Narcolepsia/psicologia , Adolescente , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Feminino , Ácido Glutâmico/metabolismo , Humanos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Narcolepsia/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Fala/fisiologia , Percepção da Fala/fisiologia , Adulto Jovem , Ácido gama-Aminobutírico/metabolismo
15.
Diagn Pathol ; 12(1): 80, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29132399

RESUMO

BACKGROUND: Steatosis is routinely assessed histologically in clinical practice and research. Automated image analysis can reduce the effort of quantifying steatosis. Since reproducibility is essential for practical use, we have evaluated different analysis methods in terms of their agreement with stereological point counting (SPC) performed by a hepatologist. METHODS: The evaluation was based on a large and representative data set of 970 histological images from human patients with different liver diseases. Three of the evaluated methods were built on previously published approaches. One method incorporated a new approach to improve the robustness to image variability. RESULTS: The new method showed the strongest agreement with the expert. At 20× resolution, it reproduced steatosis area fractions with a mean absolute error of 0.011 for absent or mild steatosis and 0.036 for moderate or severe steatosis. At 10× resolution, it was more accurate than and twice as fast as all other methods at 20× resolution. When compared with SPC performed by two additional human observers, its error was substantially lower than one and only slightly above the other observer. CONCLUSIONS: The results suggest that the new method can be a suitable automated replacement for SPC. Before further improvements can be verified, it is necessary to thoroughly assess the variability of SPC between human observers.


Assuntos
Processamento Eletrônico de Dados , Fígado Gorduroso/patologia , Hepatopatias/patologia , Fígado/patologia , Biópsia , Fígado Gorduroso/diagnóstico , Humanos , Processamento de Imagem Assistida por Computador/métodos , Hepatopatias/diagnóstico , Reprodutibilidade dos Testes
16.
PLoS One ; 12(5): e0177795, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28520793

RESUMO

PURPOSE: The aim of this study was to evaluate two post-processing techniques applied to MRS MEGA-PRESS data influenced by motion-induced artifacts. In contrast to the conventional averaging technique, order statistic filtering (OSF) is a known method for artifact reduction. Therefore, this method may be suitable to incorporate in the GABA quantification. METHODS: Twelve healthy volunteers were scanned three times using a 3 T MR system. One measurement protocol consisted of two MEGA-PRESS measurements, one reference measurement and one measurement including head motions. The resulting datasets were analyzed with the standard averaging technique and with the OSF-technique in two schemes; filtering phase cycles 'RAW PC' and filtering dynamics 'RAW Dyn'. RESULTS: The datasets containing artifacts resulted in an underestimation of the concentrations. There was a trend for the OSF-technique to compensate for this reduction when quantifying SNR-intense signals. However, there was no indication that OSF improved the estimated GABA concentrations. Moreover, when only considering the reference measurements, the OSF technique was equally as effective as averaging, which suggests that the techniques are interchangeable. CONCLUSION: OSF performed equally well as the conventional averaging technique for low-SNR signals. For high-SNR signals, OSF performed better and thus could be considered for routine usage.


Assuntos
Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/normas , Espectroscopia de Ressonância Magnética/normas , Movimento (Física) , Ácido gama-Aminobutírico/metabolismo , Adulto , Artefatos , Encéfalo/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador/normas , Imagem por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Valores de Referência
17.
PLoS One ; 12(5): e0177135, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542553

RESUMO

BACKGROUND AND PURPOSE: Damage to the blood-brain barrier with subsequent contrast enhancement is a hallmark of glioblastoma. Non-enhancing tumor invasion into the peritumoral edema is, however, not usually visible on conventional magnetic resonance imaging. New quantitative techniques using relaxometry offer additional information about tissue properties. The aim of this study was to evaluate longitudinal relaxation R1, transverse relaxation R2, and proton density in the peritumoral edema in a group of patients with malignant glioma before surgery to assess whether relaxometry can detect changes not visible on conventional images. METHODS: In a prospective study, 24 patients with suspected malignant glioma were examined before surgery. A standard MRI protocol was used with the addition of a quantitative MR method (MAGIC), which measured R1, R2, and proton density. The diagnosis of malignant glioma was confirmed after biopsy/surgery. In 19 patients synthetic MR images were then created from the MAGIC scan, and ROIs were placed in the peritumoral edema to obtain the quantitative values. Dynamic susceptibility contrast perfusion was used to obtain cerebral blood volume (rCBV) data of the peritumoral edema. Voxel-based statistical analysis was performed using a mixed linear model. RESULTS: R1, R2, and rCBV decrease with increasing distance from the contrast-enhancing part of the tumor. There is a significant increase in R1 gradient after contrast agent injection (P < .0001). There is a heterogeneous pattern of relaxation values in the peritumoral edema adjacent to the contrast-enhancing part of the tumor. CONCLUSION: Quantitative analysis with relaxometry of peritumoral edema in malignant gliomas detects tissue changes not visualized on conventional MR images. The finding of decreasing R1 and R2 means shorter relaxation times closer to the tumor, which could reflect tumor invasion into the peritumoral edema. However, these findings need to be validated in the future.


Assuntos
Edema Encefálico/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Imagem por Ressonância Magnética/métodos , Adulto , Idoso , Edema Encefálico/etiologia , Edema Encefálico/patologia , Edema Encefálico/fisiopatologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Volume Sanguíneo Cerebral , Meios de Contraste , Feminino , Gadolínio DTPA , Glioma/patologia , Glioma/fisiopatologia , Glioma/cirurgia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos
19.
Gastroenterology ; 153(1): 53-55.e7, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28286210

RESUMO

It is possible to estimate hepatic triglyceride content by calculating the proton density fat fraction (PDFF), using proton magnetic resonance spectroscopy (1H-MRS), instead of collecting and analyzing liver biopsy specimens to detect steatosis. However, the current PDFF cut-off value (5%) used to define steatosis by magnetic resonance was derived from studies that did not use histopathology as the reference standard. We performed a prospective study to determine the accuracy of 1H-MRS PDFF in the measurement of steatosis using histopathology analysis as the standard. We collected clinical, serologic, 1H-MRS PDFF, and liver biopsy data from 94 adult patients with increased levels of liver enzymes (≥6 mo) referred to the Department of Gastroenterology and Hepatology at Linköping University Hospital in Sweden from 2007 through 2014. Steatosis was graded using the conventional histopathology method and fat content was quantified in biopsy samples using stereologic point counts (SPCs). We correlated the 1H-MRS PDFF findings with SPCs (r = 0.92; P < .001). 1H-MRS PDFF results correlated with histopathology results (ρ = 0.87; P < .001), and SPCs correlated with histopathology results (ρ = 0.88; P < .001). All 25 subjects with PDFF values of 5.0% or more had steatosis based on histopathology findings (100% specificity for PDFF). However, of 69 subjects with PDFF values less than 5.0% (negative result), 22 were determined to have steatosis based on histopathology findings (53% sensitivity for PDFF). Reducing the PDFF cut-off value to 3.0% identified patients with steatosis with 100% specificity and 79% sensitivity; a PDFF cut-off value of 2.0% identified patients with steatosis with 94% specificity and 87% sensitivity. These findings might be used to improve noninvasive detection of steatosis.


Assuntos
Fígado/patologia , Espectroscopia de Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Triglicerídeos/análise , Adiposidade , Adulto , Idoso , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Sensibilidade e Especificidade
20.
JAMA Surg ; 152(4): 351-358, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27973670

RESUMO

Importance: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an innovative procedure in the treatment of noncompressible truncal hemorrhage. However, readily available fluoroscopy remains a limiting factor in its widespread implementation. Several methods have been proposed to perform REBOA without fluoroscopic guidance, and these methods were adapted predominantly from the military theater. Objective: To develop a method for performing REBOA in a civilian population using a standardized distance from a set point of entry. Design, Setting, and Participants: A retrospective study of whole-body computed tomographic (CT) scans from a cohort of 280 consecutive civilian trauma patients from University Hospitals of Lyon, France, was used to calculate the endovascular distances from both femoral arteries at the level of the upper border of the symphysis pubis to aortic zone I (descending thoracic aorta) and zone III (infrarenal aorta). These whole-body CT scans were performed between 2013 and 2015. Data were analyzed from July 16 to December 7, 2015. Main Outcomes and Measures: Two segments (1 per zone) common to all CT scans were isolated, and their location, length, prevalence in the cohort, and predicted prevalence in the general population were calculated by inverting 99% certainty tolerance limits. Results: Among the 280 trauma patients (140 men and 140 women) in this study, the mean (SD) height was 170.7 (8.7) cm, and the mean (SD) age was 38.8 (16.5) years. The common segment in zone I (414-474 mm) existed in all CT scans. The common segment in zone III (236-256 mm) existed in 99.6% and 97.9% of CT scans from the right and left femoral arteries, respectively. These segments are expected to exist in 98.7% (zone I) and 94.9% (zone III) of the general population. Conclusions and Relevance: Target distances for blind placement of REBOA exist with more than 94% prevalence in a civilian population. These findings support the expanded use of REBOA in emergency department and prehospital settings. Validation for safety and efficacy on cadaveric and clinical models is necessary.


Assuntos
Aorta , Oclusão com Balão , Procedimentos Endovasculares , Ressuscitação , Choque Hemorrágico/terapia , Tronco/lesões , Adulto , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Estudos Retrospectivos , Choque Hemorrágico/diagnóstico por imagem , Choque Hemorrágico/etiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
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