Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
J Psychiatry Neurosci ; 49(4): E242-E251, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39122408

RESUMEN

BACKGROUND: Emotional dysregulation affects up to two-thirds of adult patients with attention-deficit/hyperactivity disorder (ADHD) and is increasingly seen as a core ADHD symptom that is clinically associated with greater functional impairment and psychiatric comorbidity. We sought to investigate emotional dysregulation in ADHD and explored its neural underpinnings. METHODS: We studied emotion induction and regulation in a clinical cohort of adult patients with ADHD before and after a stimulant challenge. We compared patients with age- and gender-matched healthy controls using behavioural, structural, and functional measures. We hypothesized that patients would demonstrate aberrant emotion processing compared with healthy controls, and sought to find whether this could be normalized by stimulant medication. RESULTS: Behaviourally, the ADHD group showed reduced emotion induction and regulation capacity. Brain imaging revealed abberant activation and deactivation patterns during emotion regulation, lower grey-matter volume in limbic and paralimbic areas, and greater grey-matter volume in visual and cerebellar areas, compared with healthy controls. The behavioural and functional deficits seen in emotion induction and regulation in the ADHD group were not normalized by stimulant medication. CONCLUSION: Patients with ADHD may have impaired emotion induction and emotion regulation capacity, but these deficits are not reversed by stimulant medication. These results have important clinical implications when assessing which aspects of emotional dysregulation are relevant for patients and if and how traditional ADHD pharmacotherapy affects emotion induction and emotion regulation.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Encéfalo , Estimulantes del Sistema Nervioso Central , Imagen por Resonancia Magnética , Humanos , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Estimulantes del Sistema Nervioso Central/farmacología , Masculino , Femenino , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Encéfalo/efectos de los fármacos , Regulación Emocional/fisiología , Adulto Joven , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Sustancia Gris/efectos de los fármacos , Síntomas Afectivos/tratamiento farmacológico , Síntomas Afectivos/fisiopatología , Emociones/fisiología , Emociones/efectos de los fármacos , Estudios de Casos y Controles , Persona de Mediana Edad
2.
Eur Radiol ; 34(1): 39-49, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37552259

RESUMEN

OBJECTIVES: Quantitative CT imaging is an important emphysema biomarker, especially in smoking cohorts, but does not always correlate to radiologists' visual CT assessments. The objectives were to develop and validate a neural network-based slice-wise whole-lung emphysema score (SWES) for chest CT, to validate SWES on unseen CT data, and to compare SWES with a conventional quantitative CT method. MATERIALS AND METHODS: Separate cohorts were used for algorithm development and validation. For validation, thin-slice CT stacks from 474 participants in the prospective cross-sectional Swedish CArdioPulmonary bioImage Study (SCAPIS) were included, 395 randomly selected and 79 from an emphysema cohort. Spirometry (FEV1/FVC) and radiologists' visual emphysema scores (sum-visual) obtained at inclusion in SCAPIS were used as reference tests. SWES was compared with a commercially available quantitative emphysema scoring method (LAV950) using Pearson's correlation coefficients and receiver operating characteristics (ROC) analysis. RESULTS: SWES correlated more strongly with the visual scores than LAV950 (r = 0.78 vs. r = 0.41, p < 0.001). The area under the ROC curve for the prediction of airway obstruction was larger for SWES than for LAV950 (0.76 vs. 0.61, p = 0.007). SWES correlated more strongly with FEV1/FVC than either LAV950 or sum-visual in the full cohort (r = - 0.69 vs. r = - 0.49/r = - 0.64, p < 0.001/p = 0.007), in the emphysema cohort (r = - 0.77 vs. r = - 0.69/r = - 0.65, p = 0.03/p = 0.002), and in the random sample (r = - 0.39 vs. r = - 0.26/r = - 0.25, p = 0.001/p = 0.007). CONCLUSION: The slice-wise whole-lung emphysema score (SWES) correlates better than LAV950 with radiologists' visual emphysema scores and correlates better with airway obstruction than do LAV950 and radiologists' visual scores. CLINICAL RELEVANCE STATEMENT: The slice-wise whole-lung emphysema score provides quantitative emphysema information for CT imaging that avoids the disadvantages of threshold-based scores and is correlated more strongly with reference tests than LAV950 and reader visual scores. KEY POINTS: • A slice-wise whole-lung emphysema score (SWES) was developed to quantify emphysema in chest CT images. • SWES identified visual emphysema and spirometric airflow limitation significantly better than threshold-based score (LAV950). • SWES improved emphysema quantification in CT images, which is especially useful in large-scale research.


Asunto(s)
Obstrucción de las Vías Aéreas , Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Estudios Prospectivos , Estudios Transversales , Enfisema Pulmonar/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Enfisema/diagnóstico por imagen , Obstrucción de las Vías Aéreas/diagnóstico por imagen
3.
Acta Radiol ; 65(3): 307-317, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38115809

RESUMEN

BACKGROUND: Magnetic resonance imaging (MRI) is useful in the diagnosis of clinically significant prostate cancer (csPCa). MRI-derived radiomics may support the diagnosis of csPCa. PURPOSE: To investigate whether adding radiomics from biparametric MRI to predictive models based on clinical and MRI parameters improves the prediction of csPCa in a multisite-multivendor setting. MATERIAL AND METHODS: Clinical information (PSA, PSA density, prostate volume, and age), MRI reviews (PI-RADS 2.1), and radiomics (histogram and texture features) were retrieved from prospectively included patients examined at different radiology departments and with different MRI systems, followed by MRI-ultrasound fusion guided biopsies of lesions PI-RADS 3-5. Predictive logistic regression models of csPCa (Gleason score ≥7) for the peripheral (PZ) and transition zone (TZ), including clinical data and PI-RADS only, and combined with radiomics, were built and compared using receiver operating characteristic (ROC) curves. RESULTS: In total, 456 lesions in 350 patients were analyzed. In PZ and TZ, PI-RADS 4-5 and PSA density, and age in PZ, were independent predictors of csPCa in models without radiomics. In models including radiomics, PI-RADS 4-5, PSA density, age, and ADC energy were independent predictors in PZ, and PI-RADS 5, PSA density and ADC mean in TZ. Comparison of areas under the ROC curve (AUC) for the models without radiomics (PZ: AUC = 0.82, TZ: AUC = 0.80) versus with radiomics (PZ: AUC = 0.82, TZ: AUC = 0.82) showed no significant differences (PZ: P = 0.366; TZ: P = 0.171). CONCLUSION: PSA density and PI-RADS are potent predictors of csPCa. Radiomics do not add significant information to our multisite-multivendor dataset.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias de la Próstata , Masculino , Humanos , Imagen por Resonancia Magnética/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Antígeno Prostático Específico , Radiómica , Curva ROC , Estudios Retrospectivos
4.
BMC Psychiatry ; 23(1): 771, 2023 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872497

RESUMEN

BACKGROUND: The role of inflammation in the aetiology of schizophrenia has gained wide attention and research on the association shows an exponential growth in the last 15 years. Autoimmune diseases and severe infections are risk factors for the later development of schizophrenia, elevated inflammatory markers in childhood or adolescence are associated with a greater risk of schizophrenia in adulthood, individuals with schizophrenia have increased levels of pro-inflammatory cytokines compared to healthy controls, and autoimmune diseases are overrepresented in schizophrenia. However, treatments with anti-inflammatory agents are so far of doubtful clinical relevance. The primary objective of this study is to test whether the monoclonal antibody rituximab, directed against the B-cell antigen CD20 ameliorates psychotic symptoms in adults with schizophrenia or schizoaffective disorder and to examine potential mechanisms. A secondary objective is to examine characteristics of inflammation-associated psychosis and to identify pre-treatment biochemical characteristics of rituximab responders. A third objective is to interview a subset of patients and informants on their experiences of the trial to obtain insights that rating scales may not capture. METHODS: A proof-of-concept study employing a randomised, parallel-group, double-blind, placebo-controlled design testing the effect of B-cell depletion in patients with psychosis. 120 participants with a diagnosis of schizophrenia spectrum disorders (SSD) (ICD-10 codes F20, F25) will receive either one intravenous infusion of rituximab (1000 mg) or saline. Psychiatric measures and blood samples will be collected at baseline, week 12, and week 24 post-infusion. Brief assessments will also be made in weeks 2 and 7. Neuroimaging and lumbar puncture, both optional, will be performed at baseline and endpoints. Approximately 40 of the patients and their informants will be interviewed for qualitative analyses on the perceived changes in well-being and emotional qualities, in addition to their views on the research. DISCUSSION: This is the first RCT investigating add-on treatment with rituximab in unselected SSD patients. If the treatment is helpful, it may transform the treatment of patients with psychotic disorders. It may also heighten the awareness of immune-psychiatric disorders and reduce stigma. TRIAL REGISTRATION: NCT05622201, EudraCT-nr 2022-000220-37 version 2.1. registered 14th of October 2022.


Asunto(s)
Enfermedades Autoinmunes , Trastornos Psicóticos , Adulto , Humanos , Método Doble Ciego , Inflamación , Trastornos Psicóticos/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Rituximab/uso terapéutico , Resultado del Tratamiento
5.
Eur Radiol ; 31(8): 5980-5989, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33635394

RESUMEN

OBJECTIVES: To prospectively validate three quantitative single-energy CT (SE-CT) methods for classifying uric acid (UA) and non-uric acid (non-UA) stones. METHODS: Between September 2018 and September 2019, 116 study participants were prospectively included in the study if they had at least one 3-20-mm urinary stone on an initial urinary tract SE-CT scan. An additional dual-energy CT (DE-CT) scan was performed, limited to the stone of interest. Additionally, to include a sufficient number of UA stones, eight participants with confirmed UA stone on DE-CT were retrospectively included. The SE-CT stone features used in the prediction models were (1) maximum attenuation (maxHU) and (2) the peak point Laplacian (ppLapl) calculated at the position in the stone with maxHU. Two prediction models were previously published methods (ppLapl-maxHU and maxHU) and the third was derived from the previous results based on the k-nearest neighbors (kNN) algorithm (kNN-ppLapl-maxHU). The three methods were evaluated on this new independent stone dataset. The reference standard was the CT vendor's DE-CT application for kidney stones. RESULTS: Altogether 124 participants (59 ± 14 years, 91 men) with 106 non-UA and 37 UA stones were evaluated. For classification of UA and non-UA stones, the sensitivity, specificity, and accuracy were 100% (37/37), 97% (103/106), and 98% (140/143), respectively, for kNN-ppLapl-maxHU; 95% (35/37), 98% (104/106), and 97% (139/143) for ppLapl-maxHU; and 92% (34/37), 94% (100/106), and 94% (134/143) for maxHU. CONCLUSION: A quantitative SE-CT method (kNN-ppLapl-maxHU) can classify UA stones with accuracy comparable to DE-CT. KEY POINTS: • Single-energy CT is the first-line diagnostic tool for suspected renal colic. • A single-energy CT method based on the internal urinary stone attenuation distribution can classify urinary stones into uric acid and non-uric acid stones with high accuracy. • This immensely increases the availability of in vivo stone analysis.


Asunto(s)
Ácido Úrico , Cálculos Urinarios , Humanos , Masculino , Estudios Prospectivos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Cálculos Urinarios/diagnóstico por imagen
6.
J Digit Imaging ; 33(5): 1185-1193, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32779016

RESUMEN

Emphysema is visible on computed tomography (CT) as low-density lesions representing the destruction of the pulmonary alveoli. To train a machine learning model on the emphysema extent in CT images, labeled image data is needed. The provision of these labels requires trained readers, who are a limited resource. The purpose of the study was to test the reading time, inter-observer reliability and validity of the multi-reader-multi-split method for acquiring CT image labels from radiologists. The approximately 500 slices of each stack of lung CT images were split into 1-cm chunks, with 17 thin axial slices per chunk. The chunks were randomly distributed to 26 readers, radiologists and radiology residents. Each chunk was given a quick score concerning emphysema type and severity in the left and right lung separately. A cohort of 102 subjects, with varying degrees of visible emphysema in the lung CT images, was selected from the SCAPIS pilot, performed in 2012 in Gothenburg, Sweden. In total, the readers created 9050 labels for 2881 chunks. Image labels were compared with regional annotations already provided at the SCAPIS pilot inclusion. The median reading time per chunk was 15 s. The inter-observer Krippendorff's alpha was 0.40 and 0.53 for emphysema type and score, respectively, and higher in the apical part than in the basal part of the lungs. The multi-split emphysema scores were generally consistent with regional annotations. In conclusion, the multi-reader-multi-split method provided reasonably valid image labels, with an estimation of the inter-observer reliability.


Asunto(s)
Enfisema Pulmonar , Femenino , Humanos , Pulmón , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Enfisema Pulmonar/diagnóstico por imagen , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X
7.
Eur Radiol ; 28(4): 1692-1700, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29134354

RESUMEN

OBJECTIVES: To compare the assessment of patients with multiple sclerosis (MS) using synthetic and conventional MRI. MATERIALS AND METHODS: Synthetic and conventional axial images were prospectively acquired for 52 patients with diagnosed MS. Quantitative MRI (qMRI) was used for measuring proton density and relaxation times (T1, T2) and then, based on these parameters, synthetic T1W, T2W and FLAIR images were calculated. Image stacks were reviewed blindly, independently and in random order by two radiologists. The number and location for all lesions were documented and categorised. A combined report of lesion load and presence of contrast-enhancing lesions was compiled for each patient. Agreement was evaluated using kappa statistic. RESULTS: There was no significant difference in lesion detection using synthetic and conventional MRI in any anatomical region or for any of the three image types. Inter- and intra-observer agreements were mainly higher (p < 0.05) using conventional images but there was no significant difference in any specific region or for any image type. There was no significant difference in the outcome of the combined reports. CONCLUSION: Synthetic MR images show potential to be used in the assessment of MS dissemination in space (DIS) despite a slightly lower inter- and intra-observer agreement compared to conventional MRI. KEY POINTS: • Synthetic MR images may potentially be useful in the assessment of MS. • Examination times may be shortened. • Inter- and intra-observer agreement is generally higher using conventional MRI.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/diagnóstico por imagen , Adulto , Anciano , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/patología , Variaciones Dependientes del Observador , Protones , Factores de Tiempo , Adulto Joven
8.
J Heart Valve Dis ; 26(5): 502-508, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-29762918

RESUMEN

BACKGROUND: Flow measurements using cardiac magnetic resonance imaging (CMRI) enable quantification of the stroke volume, regurgitant volume (RV) and regurgitant fraction (RF) in patients with aortic regurgitation (AR). These variables are used to assess the severity of the valve disease and for the timing of surgery. The aim of the study was to investigate the impact of an increased heart rate on measurement of the RV and RF in patients with AR. METHODS: Among 13 patients with known moderate or severe AR, regurgitant flow measurements, using phase-contrast cine magnetic resonance imaging, were obtained in the ascending aorta. Flow measurements were obtained at rest and at increased heart rates after intravenous administration of atropine. RESULTS: The mean heart rate was 61 beats per min at rest and 91 beats per min after atropine administration. The RV and RF were 52 ml and 35% at rest, respectively, and 34 ml (p <0.001) and 30% (p = 0.065) at increased heart rate, respectively. CONCLUSIONS: An increased heart rate leads to a decreased RV. The RF is more stable and may therefore be preferable for severity grading in AR.


Asunto(s)
Insuficiencia de la Válvula Aórtica , Atropina/farmacología , Velocidad del Flujo Sanguíneo/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Anciano , Antiarrítmicos/farmacología , Insuficiencia de la Válvula Aórtica/diagnóstico , Insuficiencia de la Válvula Aórtica/fisiopatología , Ecocardiografía/métodos , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Volumen Sistólico , Tiempo de Tratamiento
9.
Cardiovasc Ultrasound ; 15(1): 4, 2017 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-28270161

RESUMEN

BACKGROUND: There is today no established approach to estimate right ventricular ejection fraction (RVEF) using 2D transthoracic echocardiography (TTE). The aim of this study was to evaluate a new method for RVEF calculations using 2D TTE and compare the results with cardiac magnetic resonance (CMR) imaging and tricuspid annular plane systolic excursion (TAPSE). METHODS: A total of 37 subjects, 25 retrospectively included patients and twelve healthy volunteers, were included to give a wide range of RVEF. The right ventricle (RV) was modeled as a part of an ellipsoid enabling calculation of the RV volume by combining three distance measurements. RVEF calculated according to the model, RVEFTTE, were compared with reference CMR-derived RVEF, RVEFCMR. Further, TAPSE was measured in the TTE images and the correlations were calculated between RVEFTTE, TAPSE and RVEFCMR. RESULTS: The mean values were RVEFCMR = 43 ± 12% (range 20-66%) and RVEFTTE = 50 ± 9% (range 34-65%). There was a high correlation (r = 0.80, p < 0.001) between RVEFTTE and RVEFCMR. Bland-Altman analysis showed a mean difference between RVEFCMR and RVEFTTE of 6 percentage points (ppt) with limits of agreement from -11 to 23 ppt. The mean value for TAPSE was 19 ± 5 mm and the correlation between TAPSE and RVEFCMR was moderate (r = 0.54, p < 0.001). The correlation between RVEFTTE and RVEFCMR was significantly higher (p < 0.05) than the correlation between TAPSE and RVEFCMR. CONCLUSIONS: The ellipsoid model shows promise for RVEF calculations using 2D TTE for a wide range of RVEF, providing RVEF estimates that were significantly better correlated to RVEF obtained from CMR compared to TAPSE.


Asunto(s)
Ventrículos Cardíacos/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Cinemagnética/métodos , Modelos Teóricos , Volumen Sistólico/fisiología , Disfunción Ventricular Derecha/fisiopatología , Función Ventricular Derecha/fisiología , Adulto , Femenino , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Disfunción Ventricular Derecha/diagnóstico
10.
Echocardiography ; 33(6): 844-53, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26841195

RESUMEN

BACKGROUND: The position of the right ventricle (RV), often partly behind the sternum, implies difficulties to image the RV free wall using transthoracic echocardiography (TTE) and consequently limits the possibilities of stroke volume calculations. The aim of this study was to evaluate whether the volume of the right ventricle (RV) can be determined by combining TTE distance measurements that do not need the RV free wall to be fully visualized. METHODS: The RV volume was approximated by an ellipsoid composed of three distances. Distance measurements, modeled RV stroke volumes (RVSV), and RV ejection fraction (RVEF) were compared to reference values obtained from cardiac magnetic resonance (CMR) imaging for 12 healthy volunteers. RESULTS: Inter-modality comparisons showed that distance measurements were significantly underestimated in TTE compared to CMR. The modeled RV volumes using TTE distance measurements were underestimated compared to reference CMR volumes. There was, however, for TTE an agreement between modeled RVSV and left ventricular stroke volumes determined by biplane Simpson's rule. Similar agreement was shown between modeled RVSV based on CMR distance measurements and the CMR reference. Regarding RVEF, further studies including patients with a wider range of RVEF are needed to evaluate the method. CONCLUSION: In conclusion, the ellipsoid model of the RV provides good estimates of RVSVs, but volumes based on distance measurements from different modalities cannot be used interchangeably.


Asunto(s)
Puntos Anatómicos de Referencia/anatomía & histología , Puntos Anatómicos de Referencia/diagnóstico por imagen , Ecocardiografía Tridimensional/métodos , Ventrículos Cardíacos/anatomía & histología , Ventrículos Cardíacos/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Adolescente , Adulto , Anciano , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Sensibilidad y Especificidad , Volumen Sistólico , Adulto Joven
11.
Acta Radiol ; 56(4): 487-92, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24646626

RESUMEN

BACKGROUND: The standard imaging procedure for a patient presenting with renal colic is unenhanced computed tomography (CT). The CT measured size has a close correlation to the estimated prognosis for spontaneous passage of a ureteral calculus. Size estimations of urinary calculi in CT images are still based on two-dimensional (2D) reformats. PURPOSE: To develop and validate a calculus oriented three-dimensional (3D) method for measuring the length and width of urinary calculi and to compare the calculus oriented measurements of the length and width with corresponding 2D measurements obtained in axial and coronal reformats. MATERIAL AND METHODS: Fifty unenhanced CT examinations demonstrating urinary calculi were included. A 3D symmetric segmentation algorithm was validated against reader size estimations. The calculus oriented size from the segmentation was then compared to the estimated size in axial and coronal 2D reformats. RESULTS: The validation showed 0.1 ± 0.7 mm agreement against reference measure. There was a 0.4 mm median bias for 3D estimated calculus length compared to 2D (P < 0.001), but no significant bias for 3D width compared to 2D. CONCLUSION: The length of a calculus in axial and coronal reformats becomes underestimated compared to 3D if its orientation is not aligned to the image planes. Future studies aiming to correlate calculus size with patient outcome should use a calculus oriented size estimation.


Asunto(s)
Imagenología Tridimensional/métodos , Tomografía Computarizada por Rayos X/métodos , Cálculos Urinarios/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos
12.
J Adv Nurs ; 70(8): 1880-90, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24456491

RESUMEN

AIMS: To describe patients' experiences of magnetic resonance examination of the liver and their experiences of two breath-hold techniques. BACKGROUND: Traditionally, patients are instructed by the radiographer to hold their breath during the examination. Alternatively, the patient can initiate the breath hold and start the image acquisition. Studies have revealed that magnetic resonance examinations can be experienced as challenging. DESIGN: Descriptive qualitative. METHODS: Semi-structured interviews were conducted with 28 patients and analysed using qualitative content analysis. The data collection was carried out from autumn 2010 to spring 2011. RESULTS: The patients' main experience was that they felt loss of control. This was described in terms of feeling trapped, being lost in time and lost as a result of uncertainty. They had many questions in their mind that they did not ask. Although their statements often revealed no clear preference regarding the techniques, almost half of the patients seemed to prefer self-initiated breath hold, as it was easier and less stressful. Those who preferred the radiographer-directed technique felt more confident leaving the responsibility to the radiographer. In general, the patients understood the importance of achieving the best quality images possible. CONCLUSION: Magnetic resonance examination can be experienced as being in loss of control. Nevertheless, not all patients wished to actively participate in magnetic resonance examination. Some preferred to hand over the responsibility to the radiographer. These results can form a base for radiographers' reflections of how to individualize and optimize the nursing care of patients undergoing magnetic resonance examinations.


Asunto(s)
Imagen por Resonancia Magnética/psicología , Respiración , Humanos , Suecia
13.
Front Pharmacol ; 15: 1412178, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39050752

RESUMEN

Psychiatric disorders are categorized on the basis of presence and absence of diagnostic criteria using classification systems such as the international classification of diseases (ICD) and the diagnostic and statistical manual for mental disorders (DSM). The research domain criteria (RDoC) initiative provides an alternative dimensional framework for conceptualizing mental disorders. In the present paper, we studied neural and behavioral effects of central stimulant (CS) medication in adults with attention deficit hyperactivity disorder (ADHD) and healthy controls using categorical and dimensional stratifications. AX-Continuous Performance Task (AX-CPT) was utilized for the later purpose, and participants were classified as "reactive" or "proactive" based on their baseline proactive behavioral index (PBI). Out of the 65 individuals who participated (33 healthy controls and 32 patients with ADHD), 53 were included in the final analysis that consisted of 31 healthy controls and 22 ADHD patients. For the dimensional stratification, a median split of PBI scores divided participants into "reactive" and "proactive" groups irrespective of whether they had ADHD or not. Participants performed AX-CPT in conjunction with functional magnetic resonance imaging (fMRI) before and after CS medication. We found no significant within or between group CS effect when participants were categorically assigned as healthy controls and ADHD patients. For the dimensional stratification, however, CS selectively increased activation in frontoparietal cognitive areas and induced a shift towards proactive control mode in the reactive group, without significantly affecting the proactive group. In conclusion, the neural and behavioral effects of CS were more clear-cut when participants were stratified into dimensional groups rather than diagnostic categories.

14.
J Psychiatr Res ; 163: 378-385, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37269772

RESUMEN

BACKGROUND: Roughly 20-30% of patients with Attention-deficit/hyperactivity disorder (ADHD) fail to respond to central stimulant (CS) medication. Genetic, neuroimaging, biochemical and behavioral biomarkers for CS response have been investigated, but currently there are no biomarkers available for clinical use that help identify CS responders and non-responders. METHODS: In the present paper, we studied if incentive salience and hedonic experience evaluated after a single-dose CS medication could predict response and non-response to CS medication. We used a bipolar visual analogue 'wanting' and 'liking' scale to gauge incentive salience and hedonic experience in 25 healthy controls (HC) and 29 ADHD patients. HC received 30 mg methylphenidate (MPH) and ADHD patients received either MPH or lisdexamphetamine (LDX) as selected by their clinician, with dosage individually determined for optimal effect. Clinician-evaluated global impression - severity (CGI-S) and improvement (CGI-I) and patient-evaluated improvement (PGI-I) were used to assess response to CS medication. Resting state functional magnetic resonance imaging (fMRI) was conducted before and after single-dose CS to correlate wanting and liking scores to changes in functional connectivity. RESULTS: Roughly 20% of the ADHD patients were CS non-responders (5 of 29). CS responders had significantly higher incentive salience and hedonic experience scores compared to healthy controls and CS non-responders. Resting state fMRI showed that wanting scores were significantly associated to changes in functional connectivity in ventral striatum including nucleus accumbens. CONCLUSION: Incentive salience and hedonic experience evaluated after a single-dose CS medication segregate CS responders and non-responders, with corresponding neuroimaging biomarkers in the brain reward system.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Estimulantes del Sistema Nervioso Central , Metilfenidato , Humanos , Estimulantes del Sistema Nervioso Central/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Motivación , Metilfenidato/farmacología , Metilfenidato/uso terapéutico
15.
Eur Radiol ; 22(4): 731-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22160167

RESUMEN

OBJECTIVES: The size estimation in CT images of an obstructing ureteral calculus is important for the clinical management of a patient presenting with renal colic. The objective of the present study was to develop a reader independent urinary calculus segmentation algorithm using well-known digital image processing steps and to validate the method against size estimations by several readers. METHODS: Fifty clinical CT examinations demonstrating urinary calculi were included. Each calculus was measured independently by 11 readers. The mean value of their size estimations was used as validation data for each calculus. The segmentation algorithm consisted of interpolated zoom, binary thresholding and morphological operations. Ten examinations were used for algorithm optimisation and 40 for validation. Based on the optimisation results three segmentation method candidates were identified. RESULTS: Between the primary segmentation algorithm using cubic spline interpolation and the mean estimation by 11 readers, the bias was 0.0 mm, the standard deviation of the difference 0.26 mm and the Bland-Altman limits of agreement 0.0 ± 0.5 mm. CONCLUSIONS: The validation showed good agreement between the suggested algorithm and the mean estimation by a large number of readers. The limit of agreement was narrower than the inter-reader limit of agreement previously reported for the same data. KEY POINTS: The size of kidney stones is usually estimated manually by the radiologist. An algorithm for computer-aided size estimation is introduced. The variability between readers can be reduced. A reduced variability can give better information for treatment decisions.


Asunto(s)
Algoritmos , Reconocimiento de Normas Patrones Automatizadas/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Cálculos Urinarios/diagnóstico por imagen , Urografía/métodos , Humanos , Variaciones Dependientes del Observador , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Acta Radiol ; 53(9): 995-1003, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22983258

RESUMEN

BACKGROUND: Magnetic resonance (MR) imaging and echocardiography both allow assessment of aortic valve stenosis. In MR the aortic valve area (AvA) is measured using planimetry while in transthoracic echocardiography (TTE) AvA is usually calculated by applying the continuity equation. PURPOSE: To compare the measured stenotic aortic valve areas using five different MR-acquisition alternatives with the corresponding area values calculated by TTE. MATERIAL AND METHODS: The aortic valve was imaged in 14 patients, with diagnosed aortic valve stenosis, using balanced steady state free precession (bSSFP) gradient echo (GE) and phase contrast imaging (PC). Three adjacent slices were planned to encompass the aortic valve and the aortic valve area was measured using planimetry. The two sets of complex valued images generated by the PC sequence formed three kinds of images that could be used for aortic valve area measurements: the magnitude image (PC/Mag), the modulus (PCA/M), and phase difference (PCA/P) between the two complex images, respectively. The valve area from TTE was calculated using the continuity equation. A cut-off of <1.0 cm(2) was used as a criteria for severe stenosis. RESULTS: The mean area differences between the different MR acquisitions and TTE method were -0.05 ± 0.37 cm(2) (GE), -0.18 ± 0.46 cm(2) (bSSFP), 0.27 ± 0.43 cm(2) (PC/Mag), 0.15 ± 0.32 cm(2) (PCA/P), and 0.26 ± 0.27 cm(2) (PCA/M). The valve area was significantly overestimated using PCA/M that, in turn, implied a significant underestimation of the aortic valve stenosis severity compared to the assessments using TTE. CONCLUSION: The smallest area valve difference between TTE and an MR-acquisition alternative is obtained with gradient echo images. The use of PCA/M leads to significant differences in planimetry measurements of the aortic valve orifice and the gradation of the stenosis severity compared to TTE.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico , Ecocardiografía/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Estadísticas no Paramétricas
17.
Cells ; 11(18)2022 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-36139496

RESUMEN

Probiotics can alter brain function via the gut-brain axis. We investigated the effect of a probiotic mixture containing Bifidobacterium longum, Lactobacillus helveticus and Lactiplantibacillus plantarum. In a randomized, placebo-controlled, double-blinded crossover design, 22 healthy subjects (6 m/16 f; 24.2 ± 3.4 years) underwent four-week intervention periods with probiotics and placebo, separated by a four-week washout period. Voxel-based morphometry indicated that the probiotic intervention affected the gray matter volume of a cluster covering the left supramarginal gyrus and superior parietal lobule (p < 0.0001), two regions that were also among those with an altered resting state functional connectivity. Probiotic intervention resulted in significant (FDR < 0.05) functional connectivity changes between regions within the default mode, salience, frontoparietal as well as the language network and several regions located outside these networks. Psychological symptoms trended towards improvement after probiotic intervention, i.e., the total score of the Hospital Anxiety and Depression Scale (p = 0.056) and its depression sub-score (p = 0.093), as well as sleep patterns (p = 0.058). The probiotic intervention evoked distinct changes in brain morphology and resting state brain function alongside slight improvements of psycho(bio)logical markers of the gut-brain axis. The combination of those parameters may provide new insights into the modes of action by which gut microbiota can affect gut-brain communication and hence brain function.


Asunto(s)
Bifidobacterium longum , Lactobacillus helveticus , Probióticos , Encéfalo , Voluntarios Sanos , Humanos , Probióticos/uso terapéutico
18.
Nutrients ; 14(7)2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35405944

RESUMEN

Probiotics are suggested to impact physiological and psychological stress responses by acting on the gut-brain axis. We investigated if a probiotic product containing Bifidobacterium longum R0175, Lactobacillus helveticus R0052 and Lactiplantibacillus plantarum R1012 affected stress processing in a double-blinded, randomised, placebo-controlled, crossover proof-of-concept study (NCT03615651). Twenty-two healthy subjects (24.2 ± 3.4 years, 6 men/16 women) underwent a probiotic and placebo intervention for 4 weeks each, separated by a 4-week washout period. Subjects were examined by functional magnetic resonance imaging while performing the Montreal Imaging Stress Task (MIST) as well as an autonomic nervous system function assessment during the Stroop task. Reduced activation in regions of the lateral orbital and ventral cingulate gyri was observed after probiotic intervention compared to placebo. Significantly increased functional connectivity was found between the upper limbic region and medioventral area. Interestingly, probiotic intervention seemed to predominantly affect the initial stress response. Salivary cortisol secretion during the task was not altered. Probiotic intervention did not affect cognitive performance and autonomic nervous system function during Stroop. The probiotic intervention was able to subtly alter brain activity and functional connectivity in regions known to regulate emotion and stress responses. These findings support the potential of probiotics as a non-pharmaceutical treatment modality for stress-related disorders.


Asunto(s)
Bifidobacterium longum , Lactobacillus helveticus , Probióticos , Encéfalo/diagnóstico por imagen , Método Doble Ciego , Femenino , Voluntarios Sanos , Humanos , Masculino
19.
Front Nutr ; 9: 827182, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35571902

RESUMEN

Background: Evidence from preclinical studies suggests that probiotics affect brain function via the microbiome-gut-brain axis, but evidence in humans remains limited. Objective: The present proof-of-concept study investigated if a probiotic product containing a mixture of Bifidobacterium longum R0175, Lactobacillus helveticus R0052 and Lactiplantibacillus plantarum R1012 (in total 3 × 109 CFU/day) affected functional brain responses in healthy subjects during an emotional attention task. Design: In this double-blinded, randomized, placebo-controlled crossover study (Clinicaltrials.gov, NCT03615651), 22 healthy subjects (24.2 ± 3.4 years, 6 males/16 females) were exposed to a probiotic intervention and a placebo for 4 weeks each, separated by a 4-week washout period. Subjects underwent functional magnetic resonance imaging while performing an emotional attention task after each intervention period. Differential brain activity and functional connectivity were assessed. Results: Altered brain responses were observed in brain regions implicated in emotional, cognitive and face processing. Increased activation in the orbitofrontal cortex, a region that receives extensive sensory input and in turn projects to regions implicated in emotional processing, was found after probiotic intervention compared to placebo using a cluster-based analysis of functionally defined areas. Significantly reduced task-related functional connectivity was observed after the probiotic intervention compared to placebo. Fecal microbiota composition was not majorly affected by probiotic intervention. Conclusion: The probiotic intervention resulted in subtly altered brain activity and functional connectivity in healthy subjects performing an emotional task without major effects on the fecal microbiota composition. This indicates that the probiotic effects occurred via microbe-host interactions on other levels. Further analysis of signaling molecules could give possible insights into the modes of action of the probiotic intervention on the gut-brain axis in general and brain function specifically. The presented findings further support the growing consensus that probiotic supplementation influences brain function and emotional regulation, even in healthy subjects. Future studies including patients with altered emotional processing, such as anxiety or depression symptoms are of great interest. Clinical Trial Registration: [http://clinicaltrials.gov/], identifier [NCT03615651].

20.
J Digit Imaging ; 24(3): 470-7, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20358243

RESUMEN

The purpose of this work was to develop a visualization method for concurrent observation of both velocity and magnitude data obtained from through-plane velocity measurements using phase-contrast magnetic resonance imaging. Magnitude and velocity images were combined using an opacity transfer function (OTF) where the opacity was a function of a velocity range defined by the velocity encoding (v (enc)) parameter. Measured velocities were color-coded according to a predefined color scale and then combined into one image with the gray-scale magnitude image according to the OTF. In the combined images, simultaneous information of velocity and anatomy was presented. The proposed visualization method facilitated the understanding of how the measured blood flow was related to the underlying anatomy. Results are shown where the method is used to visualize blood flow measurements in the ascending aorta and the aortic valve. Adjustments of the OTF render possible identification of the peak velocities and their localization. Forward and backward blood flow is easily shown when applying appropriate OTF and color-coding. An advantage when using the proposed method is the ability of developing standardized protocol settings since the velocity information is quantitative and not relative as is the case for data obtained from the magnitude images. The intended application of the visualization method is the analysis of common flow studies used in the diagnosis of different cardiovascular diseases.


Asunto(s)
Aorta/anatomía & histología , Válvula Aórtica/anatomía & histología , Imagen por Resonancia Magnética/métodos , Flujo Pulsátil , Velocidad del Flujo Sanguíneo , Circulación Coronaria , Humanos , Imagenología Tridimensional/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA