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1.
Clin Neurophysiol ; 154: 49-59, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37549613

RESUMEN

OBJECTIVE: The aim of this study was to explore differences in functional connectivity and network organization between very preterm born adolescents and term born controls and to investigate if these differences might explain the relation between preterm birth and adverse long-term outcome. METHODS: Forty-seven very preterm born adolescents (53% males) and 54 controls (54% males) with matching age, sex and parental educational levels underwent high-density electroencephalography (EEG) at 13 years of age. Long-term outcome was assessed by Intelligence Quotient (IQ), motor, attentional functioning and academic performance. Two minutes of EEG data were analysed within delta, theta, lower alpha, upper alpha and beta frequency bands. Within each frequency band, connectivity was assessed using the Phase Lag Index (PLI) and Amplitude Envelope Correlation, corrected for volume conduction (AEC-c). Brain networks were constructed using the minimum spanning tree method. RESULTS: Very preterm born adolescents had stronger beta PLI connectivity and less differentiated network organization. Beta AEC-c and differentiation of AEC-c based networks were negatively associated with long-term outcomes. EEG measures did not mediate the relation between preterm birth and outcomes. CONCLUSIONS: This study shows that very preterm born adolescents may have altered functional connectivity and brain network organization in the beta frequency band. Alterations in measures of functional connectivity and network topologies, especially its differentiating characteristics, were associated with neurodevelopmental functioning. SIGNIFICANCE: The findings indicate that EEG connectivity and network analysis is a promising tool for investigating underlying mechanisms of impaired functioning.


Asunto(s)
Nacimiento Prematuro , Masculino , Femenino , Humanos , Recién Nacido , Adolescente , Electroencefalografía/métodos , Encéfalo , Mapeo Encefálico/métodos , Atención
2.
Neuropediatrics ; 54(1): 44-52, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36223877

RESUMEN

BACKGROUND: Dystonia is characterized by sustained or intermittent muscle contractions, leading to abnormal posturing and twisting movements. In pediatric patients, dystonia often negatively influences quality of life. Pharmacological treatment for dystonia is often inadequate and causes adverse effects. Deep brain stimulation (DBS) appears to be a valid therapeutic option for pharmacoresistant dystonia in children. METHODS: To illustrate the current clinical practice, we hereby describe two pediatric cases of monogenetic movement disorders presenting with dystonia and treated with DBS. We provide a literature review of similar previously described cases and on different clinical aspects of DBS in pediatric dystonia. RESULTS: The first patient, a 6-year-old girl with severe dystonia, chorea, and myoclonus due to an ADCY5 gene mutation, received DBS in an elective setting. The second patient, an 8-year-old boy with GNAO1-related dystonia and chorea, underwent emergency DBS due to a pharmacoresistant status dystonicus. A significant amelioration of motor symptoms (65% on the Burke-Fahn-Marsden Dystonia Rating Scale) was observed postoperatively in the first patient and her personal therapeutic goals were achieved. DBS was previously reported in five patients with ADCY5-related movement disorders, of which three showed objective improvement. Emergency DBS in our second patient resulted in the successful termination of his GNAO1-related status dystonicus, this being the eighth case reported in the literature. CONCLUSION: DBS can be effective in monogenetic pediatric dystonia and should be considered early in the disease course. To better evaluate the effects of DBS on patients' functioning, patient-centered therapeutic goals should be discussed in a multidisciplinary approach.


Asunto(s)
Corea , Estimulación Encefálica Profunda , Distonía , Trastornos Distónicos , Trastornos del Movimiento , Masculino , Femenino , Humanos , Niño , Distonía/complicaciones , Distonía/genética , Distonía/terapia , Corea/complicaciones , Corea/genética , Corea/terapia , Estimulación Encefálica Profunda/efectos adversos , Estimulación Encefálica Profunda/métodos , Calidad de Vida , Globo Pálido , Resultado del Tratamiento , Trastornos Distónicos/genética , Trastornos Distónicos/terapia , Trastornos Distónicos/complicaciones , Trastornos del Movimiento/genética , Trastornos del Movimiento/terapia , Trastornos del Movimiento/complicaciones , Subunidades alfa de la Proteína de Unión al GTP Gi-Go
3.
J Biol Eng ; 12: 21, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30305842

RESUMEN

BACKGROUND: The ability to direct the cellular response by means of biomaterial surface topography is important for biomedical applications. Substrate surface topography has been shown to be an effective cue for the regulation of cellular response. Here, the response of human aortic endothelial cells to nanoporous anodic alumina and macroporous silicon with collagen and fibronectin functionalization has been studied. METHODS: Confocal microscopy and scanning electron microscopy were employed to analyse the effects of the material and the porosity on the adhesion, morphology, and proliferation of the cells. Cell spreading and filopodia formation on macro- and nanoporous material was characterized by atomic force microscopy. We have also studied the influence of the protein on the adhesion. RESULTS: It was obtained the best results when the material is functionalized with fibronectin, regarding cells adhesion, morphology, and proliferation. CONCLUSION: These results permit to obtain chemical modified 3D structures for several biotechnology applications such as tissue engineering, organ-on-chip or regenerative medicine.

4.
J Thromb Haemost ; 16(5): 858-865, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29460484

RESUMEN

Essentials Decision rules for pulmonary embolism are used indiscriminately despite possible sex-differences. Various pre-imaging diagnostic algorithms have been investigated in several prospective studies. When analysed at an individual patient data level the algorithms perform similarly in both sexes. Estrogen use and male sex were associated with a higher prevalence in suspected pulmonary embolism. SUMMARY: Background In patients suspected of pulmonary embolism (PE), clinical decision rules are combined with D-dimer testing to rule out PE, avoiding the need for imaging in those at low risk. Despite sex differences in several aspects of the disease, including its diagnosis, these algorithms are used indiscriminately in women and men. Objectives To compare the performance, defined as efficiency and failure rate, of three pre-imaging diagnostic algorithms for PE between women and men: the Wells rule with fixed or with age-adjusted D-dimer cut-off, and a recently validated algorithm (YEARS). A secondary aim was to determine the sex-specific prevalence of PE. Methods Individual patient data were obtained from six studies using the Wells rule (fixed D-dimer, n = 5; age adjusted, n = 1) and from one study using the YEARS algorithm. All studies prospectively enrolled consecutive patients with suspected PE. Main outcomes were efficiency (proportion of patients in which the algorithm ruled out PE without imaging) and failure rate (proportion of patients with PE not detected by the algorithm). Outcomes were estimated using (multilevel) logistic regression models. Results The main outcomes showed no sex differences in any of the separate algorithms. With all three, the prevalence of PE was lower in women (OR, 0.66, 0.68 and 0.74). In women, estrogen use, adjusted for age, was associated with lower efficiency and higher prevalence and D-dimer levels. Conclusions The investigated pre-imaging diagnostic algorithms for patients suspected of PE show no sex differences in performance. Male sex and estrogen use are both associated with a higher probability of having the disease.


Asunto(s)
Algoritmos , Técnicas de Apoyo para la Decisión , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Embolia Pulmonar/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estrógenos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prevalencia , Pronóstico , Embolia Pulmonar/sangre , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/epidemiología , Reproducibilidad de los Resultados , Factores de Riesgo , Factores Sexuales , Adulto Joven
5.
J Thromb Haemost ; 16(4): 725-733, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29431911

RESUMEN

Essentials The YEARS algorithm was designed to simplify the diagnostic workup of suspected pulmonary embolism. We compared emergency ward turnaround time of YEARS and the conventional algorithm. YEARS was associated with a significantly shorter emergency department visit time of ˜60 minutes. Treatment of pulmonary embolism was initiated 53 minutes earlier with the YEARS algorithm SUMMARY: Background Recently, the safety of the YEARS algorithm, designed to simplify the diagnostic work-up of pulmonary embolism (PE), was demonstrated. We hypothesize that by design, YEARS would be associated with a shorter diagnostic emergency department (ED) visit time due to simultaneous assessment of pre-test probability and D-dimer level and reduction in number of CT scans. Aim To investigate whether implementation of the YEARS diagnostic algorithm is associated with a shorter ED visit time compared with the conventional algorithm and to evaluate the associated cost savings. Methods We selected consecutive outpatients with suspected PE from our hospital included in the YEARS study and ADJUST-PE study. Different time-points of the diagnostic process were extracted from the to-the-minute accurate electronic patients' chart system of the ED. Further, the costs of the ED visits were estimated for both algorithms. Results All predefined diagnostic turnaround times were significantly shorter after implementation of YEARS: patients were discharged earlier from the ED; 54 min (95% CI, 37-70) for patients managed without computed tomography pulmonary angiography (CTPA) and 60 min (95% CI, 44-76) for the complete study population. Importantly, patients diagnosed with PE by CTPA received the first dose of anticoagulants 53 min (95% CI, 22-82) faster than those managed according to the conventional algorithm. Total costs were reduced by on average €123 per visit. Conclusion YEARS was shown to be associated with a shorter ED visit time compared with the conventional diagnostic algorithm, leading to faster start of treatment in the case of confirmed PE and savings on ED resources.


Asunto(s)
Algoritmos , Técnicas de Apoyo para la Decisión , Servicios Médicos de Urgencia/economía , Servicios Médicos de Urgencia/métodos , Costos de Hospital , Tiempo de Internación/economía , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/economía , Adulto , Anciano , Biomarcadores/sangre , Ahorro de Costo , Análisis Costo-Beneficio , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Evaluación de Programas y Proyectos de Salud , Embolia Pulmonar/sangre , Embolia Pulmonar/terapia , Tiempo de Tratamiento/economía , Tomografía Computarizada por Rayos X/economía , Procedimientos Innecesarios/economía
6.
Thromb Haemost ; 118(3): 547-552, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29390226

RESUMEN

BACKGROUND: Both the YEARS algorithm and the pulmonary embolism (PE) rule-out criteria (PERC) were created to exclude PE with limited diagnostic tests. A diagnostic strategy combining both scores might save additional computed tomography pulmonary angiography (CTPA) scans, but they have never been evaluated in conjunction. AIM: The aim of this study was to determine the safety and efficiency of combining YEARS and PERC in a single diagnostic strategy for suspected PE. METHODS: The PERC rule was assessed in 1,316 consecutive patients with suspected PE who were managed according to YEARS. We calculated the absolute difference (with 95% confidence interval [CI]) in failure rate and the number of 'saved' CTPAs for the scenario that PE would have been ruled out without CTPA in the absence of all PERC items. RESULTS: Using the YEARS algorithm, PE was diagnosed in 189 patients (14%), 680 patients (52%) were managed without CTPA and the 3-month rate of venous thromboembolism in patients in whom PE was ruled out was 0.44% (95% CI: 0.19-1.0). Only 6 of 154 patients (3.9%; 95% CI: 1.4-8.2) with no YEARS items who were referred for CTPA would have been PERC negative, of whom none were diagnosed with PE at baseline or during follow-up (0%; 95% CI: 0-64). Applying PERC before YEARS in all patients would have led to a failure rate of 1.42% (95% CI: 0.87-2.3%), 0.98% (95% CI: 0.17-1.9) more than shown in patients managed by YEARS. CONCLUSION: Combining YEARS with PERC would have yielded only a modest improvement of efficiency in patients without a YEARS item and an unacceptable failure rate in patients with ≥ 1 YEARS item.


Asunto(s)
Embolia Pulmonar/diagnóstico , Neumología/normas , Adulto , Anciano , Algoritmos , Estudios de Cohortes , Angiografía por Tomografía Computarizada , Pruebas Diagnósticas de Rutina , Europa (Continente)/epidemiología , Femenino , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Embolia Pulmonar/complicaciones , Tomografía Computarizada por Rayos X , Tromboembolia Venosa/complicaciones
7.
J Thromb Haemost ; 15(12): 2317-2324, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28941051

RESUMEN

Essentials Imaging is warranted in the majority of patients to confirm or rule out pulmonary embolism (PE). The age-adjusted D-dimer (ADJUST) reduced the number of required imaging tests in patients ≥ 50 years. The YEARS algorithm was designed to improve the efficiency in patients with suspected PE. There was no added value of implementing ADJUST in the YEARS algorithm in our cohort. SUMMARY: Background The YEARS algorithm was designed to simplify the diagnostic work-up of pulmonary embolism (PE) and to reduce the number of necessary computed tomography pulmonary angiography (CTPA) scans. An alternative strategy to reduce the number of CTPAs is the age-adjusted D-dimer cut-off (ADJUST) in patients aged 50 years or older. We aimed to investigate whether a combination of both diagnostic strategies might save additional CTPAs. Methods The YEARS algorithm consists of three items (clinical signs of deep venous thrombosis, hemoptysis, 'PE most likely diagnosis') with simultaneous D-dimer testing using a pre-test dependent threshold. We performed a post hoc analysis in 3465 patients managed according to YEARS to compare the number of patients managed without CTPA scans and associated diagnostic failures in hypothetical scenarios with different YEARS-ADJUST combinations. Results Following the YEARS algorithm, 1651 patients (48%) were managed without CTPA; PE was diagnosed in 456 (13%) patients at baseline and 18 patients with initial normal testing suffered venous thromboembolism (VTE) during 3-month follow-up (failure rate 0.61%; 95% confidence interval [CI], 0.36-0.96). If ADJUST had been fully integrated in YEARS, 1627 patients (47%) would have been managed without CTPA (absolute decrease of 0.69%; 95% CI -1.7 to 3.0), at cost of four additional missed PE diagnoses at baseline, for a projected 3-month VTE failure rate of 0.75% (95% CI, 0.49-1.13). None of the other studied scenarios showed relevant improvements in efficiency as well, but all led to more missed diagnoses. Conclusion In our cohort, there was no added value of implementing ADJUST in the YEARS algorithm.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Embolia Pulmonar/sangre , Embolia Pulmonar/diagnóstico , Anciano , Algoritmos , Angiografía por Tomografía Computarizada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Embolia Pulmonar/diagnóstico por imagen , Diseño de Software
8.
Ned Tijdschr Geneeskd ; 161: D1372, 2017.
Artículo en Holandés | MEDLINE | ID: mdl-28612695

RESUMEN

Peritoneal tuberculosis was diagnosed in a 38-year-old man from Curaçao, a 42-year-old Dutch man and a 38-year-old woman from Surinam. All patients had been living in the Netherlands for over a decade at the time of diagnosis. Time to diagnosis and treatment varied between patients. Factors contributing to delayed diagnosis were nonspecific symptoms, failure to consider tuberculosis exposure, consulting of more than one physician and delay in obtaining adequate material for histopathologic and microbiologic tests. These cases show that peritoneal tuberculosis can represent a diagnostic challenge. Considering the rising incidence of tuberculosis in the Netherlands, general practitioners and medical specialists will encounter patients with extrapulmonary tuberculosis more frequently. We recommend that tuberculosis exposure should always be considered by clinicians, even in patients originating from non-endemic countries. In case of suspected peritoneal tuberculosis, laparoscopy with peritoneal biopsy is the diagnostic tool of choice and should be performed without delay.


Asunto(s)
Peritoneo/patología , Peritonitis Tuberculosa/diagnóstico , Adulto , Biopsia , Curazao , Diagnóstico Tardío , Emigrantes e Inmigrantes , Femenino , Humanos , Incidencia , Laparoscopía , Masculino , Países Bajos , Suriname , Tuberculosis
9.
Eur J Paediatr Neurol ; 21(5): 703-706, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28549726

RESUMEN

OBJECTIVE: Cerebral palsy (CP) can be classified as spastic, dyskinetic, ataxic or combined. Correct classification is essential for symptom-targeted treatment. This study aimed to investigate agreement among professionals on the phenotype of children with CP based on standardized videos. METHODS: In a prospective, observational pilot study, videos of fifteen CP patients (8 boys, mean age 11 ± 5 y) were rated by three pediatric neurologists, three rehabilitation physicians and three movement disorder specialists. They scored the presence and severity of spasticity, ataxia or dyskinesias/dystonia. Inter- and intraobserver agreement were calculated using Cohen's and Fleiss' kappa. RESULTS: We found a fair inter-observer (κ = 0.36) and moderate intra-observer agreement (κ = 0.51) for the predominant motor symptom. This only slightly differed within the three groups of specialists (κ = 0.33-0.55). CONCLUSION: A large variability in the phenotyping of CP children was detected, not only between but also within clinicians, calling for a discussing on the operational definitions of spasticity, dystonia and ataxia. In addition, the low agreement found in our study questions the reliability of use of videos to measure intervention outcomes, such as deep brain stimulation in dystonic CP. Future studies should include functional domains to assess the true impact of management options in this highly challenging patient population.


Asunto(s)
Ataxia/diagnóstico , Parálisis Cerebral/clasificación , Parálisis Cerebral/diagnóstico , Distonía/diagnóstico , Espasticidad Muscular/diagnóstico , Adolescente , Ataxia/etiología , Parálisis Cerebral/complicaciones , Niño , Diagnóstico Diferencial , Distonía/etiología , Femenino , Humanos , Masculino , Espasticidad Muscular/etiología , Variaciones Dependientes del Observador , Proyectos Piloto , Estudios Prospectivos , Reproducibilidad de los Resultados , Grabación de Cinta de Video
10.
Blood Rev ; 31(2): 31-36, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27720446

RESUMEN

Because pregnant women have an increased risk of venous thromboembolism (VTE) and at the same time normal pregnancy is associated with symptoms, mimicking those present in the setting of acute pulmonary embolism (PE), the latter diagnosis is frequently suspected in this patient category. Since imaging tests expose both mother and foetus to ionizing radiation, the ability to rule out PE based on non-radiological diagnostic tests is of paramount importance. However, clinical decision rules have only been scarcely evaluated in the pregnant population with suspected PE, while D-dimer levels lose diagnostic accuracy due to a physiological increase during normal pregnancy. Consequently, clinical guidelines provide contradicting and weak recommendations on this subject and the optimal diagnostic strategy remains highly debated. With this systematic review, we aimed to summarize current evidence on the safety and efficacy of clinical decision rules and biomarkers used in the diagnostic management of suspected acute PE in pregnant patients.


Asunto(s)
Pruebas de Coagulación Sanguínea , Técnicas de Apoyo para la Decisión , Productos de Degradación de Fibrina-Fibrinógeno , Complicaciones Hematológicas del Embarazo/diagnóstico , Complicaciones Hematológicas del Embarazo/etiología , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiología , Algoritmos , Biomarcadores , Femenino , Humanos , Guías de Práctica Clínica como Asunto , Embarazo , Complicaciones Hematológicas del Embarazo/sangre , Pronóstico , Embolia Pulmonar/sangre , Tromboembolia Venosa/sangre , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiología
11.
Eur J Paediatr Neurol ; 21(2): 350-357, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27908676

RESUMEN

BACKGROUND: In non-walking children with severe spasticity, daily care can be difficult and many patients suffer from pain. Selective dorsal rhizotomy (SDR) reduces spasticity in the legs, and therefore has the potential to improve daily care and comfort. AIM: To examine effects of SDR on daily care and comfort in non-walking children with severe spasticity due to different underlying neurological conditions. METHODS: Medical history, changes in daily care and comfort and satisfaction with outcome were assessed retrospectively in non-walking children who underwent SDR in our center, with a mean follow-up of 1y 7m (range 11m-4y 3m). All eligible patients (n = 24, years 2009-2014) were included. RESULTS: Mean age at SDR was 12y 4m (SD 4y 3m, range 2y 8m-19y 3m). Associated orthopaedic problems were frequent. Seven patients underwent scoliosis correction in the same session. Most improvements were reported in dressing (n = 16), washing (n = 12) and comfort (n = 10). Median score for satisfaction was 7 on a scale of 10 (range 1-9). SDR resulted in reduction of spasticity in leg muscles. In nine patients dystonia was recorded post-operatively, mainly in children with congenital malformations and syndromes. INTERPRETATION: SDR is a single event intervention that can improve daily care and comfort in non-walking children with severe spasticity, and can safely be combined with scoliosis correction. Despite the improvements, satisfaction is variable. Careful attention is necessary for risk factors for dystonia, which may be unmasked after SDR.


Asunto(s)
Espasticidad Muscular/cirugía , Atención al Paciente , Comodidad del Paciente , Rizotomía , Adolescente , Niño , Preescolar , Distonía/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Masculino , Procedimientos Ortopédicos , Satisfacción del Paciente , Complicaciones Posoperatorias , Estudios Retrospectivos , Rizotomía/efectos adversos , Rizotomía/métodos , Escoliosis/cirugía , Resultado del Tratamiento , Caminata , Adulto Joven
13.
Biotechnol Bioeng ; 104(3): 492-504, 2009 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19598176

RESUMEN

A licensed pharmaceutical process is required to be executed within the validated ranges throughout the lifetime of product manufacturing. Changes to the process, especially for processes involving biological products, usually require the manufacturer to demonstrate that the safety and efficacy of the product remains unchanged by new or additional clinical testing. Recent changes in the regulations for pharmaceutical processing allow broader ranges of process settings to be submitted for regulatory approval, the so-called process design space, which means that a manufacturer can optimize his process within the submitted ranges after the product has entered the market, which allows flexible processes. In this article, the applicability of this concept of the process design space is investigated for the cultivation process step for a vaccine against whooping cough disease. An experimental design (DoE) is applied to investigate the ranges of critical process parameters that still result in a product that meets specifications. The on-line process data, including near infrared spectroscopy, are used to build a descriptive model of the processes used in the experimental design. Finally, the data of all processes are integrated in a multivariate batch monitoring model that represents the investigated process design space. This article demonstrates how the general principles of PAT and process design space can be applied for an undefined biological product such as a whole cell vaccine. The approach chosen for model development described here, allows on line monitoring and control of cultivation batches in order to assure in real time that a process is running within the process design space.


Asunto(s)
Vacunas Bacterianas/normas , Bordetella pertussis/crecimiento & desarrollo , Tecnología Farmacéutica/métodos , Tecnología Farmacéutica/normas , Aprobación de Drogas
14.
J Neurol Neurosurg Psychiatry ; 80(10): 1069-74, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19541689

RESUMEN

BACKGROUND: Clinical subtypes of mild cognitive impairment (MCI) may represent different underlying aetiologies. METHODS: This European, multicentre, memory clinic based study (DESCRIPA) of non-demented subjects investigated whether MCI subtypes have different brain correlates on MRI and whether the relation between subtypes and brain pathology is modified by age. Using visual rating scales, medial temporal lobe atrophy (MTA) (0-4) and white matter hyperintensities (WMH) (0-30) were assessed. RESULTS: Severity of MTA differed between MCI subtypes (p<0.001), increasing from a mean of 0.8 (SD 0.7) in subjective complaints (n = 77) to 1.3 (0.8) in non-amnestic MCI (n = 93), and from 1.4 (0.9) in single domain amnestic MCI (n = 70) to 1.7 (0.9) in multiple domain amnestic MCI (n = 89). The association between MCI subtype and MTA was modified by age and mainly present in subjects >70 years of age. Severity of WMH did not differ between MCI subtypes (p = 0.21). However, the combination of MTA and WMH differed between MCI subtypes (p = 0.02) CONCLUSION: We conclude that MCI subtypes may have different brain substrates, especially in older subjects. Isolated MTA was mainly associated with amnestic MCI subtypes, suggesting AD as the underlying cause. In non-amnestic MCI, the relatively higher prevalence of MTA in combination with WMH may suggest a different pathophysiological origin.


Asunto(s)
Amnesia/etiología , Amnesia/patología , Trastornos del Conocimiento/patología , Trastornos del Conocimiento/psicología , Lóbulo Temporal/patología , Factores de Edad , Anciano , Atrofia/etiología , Atrofia/patología , Atrofia/psicología , Estudios de Casos y Controles , Trastornos del Conocimiento/etiología , Estudios de Cohortes , Escolaridad , Europa (Continente) , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Factores Sexuales
15.
Neurology ; 69(15): 1491-7, 2007 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-17923611

RESUMEN

OBJECTIVE: A large cohort of subjects with mild cognitive impairment (MCI) was categorized into tertiles based on hippocampal atrophy rates, as a proxy for Alzheimer-type pathology. We compared baseline clinical, neuropsychological, and MRI measures to characterize these MCI subgroups. METHODS: Serial MRI data of 323 subjects with MCI (49% men; mean +/- SD age: 69 +/- 9 years), followed for 2 years in a clinical trial, were available. Baseline hippocampal and whole brain volumes (WBV) were measured, and hippocampal volume change was assessed. Baseline medial temporal lobe atrophy (MTA), white matter hyperintensities (WMH), and lacunes were rated visually. The cohort was categorized into tertiles based on hippocampal atrophy rates (absent, moderate, and severe). RESULTS: Rates of hippocampal atrophy (%/year) were 0.0 +/- 0.8 in the absent, 1.7 +/- 0.4 in the moderate, and 3.6 +/- 1.0 in the severe (mean +/- SD) tertile. Older age and the APOE epsilon 4 allele were associated with higher hippocampal atrophy rates (p < 0.0001 and p = 0.015). General cognition deteriorated over the MCI groups (p < 0.0001), whereas, after adjustment for age and sex, episodic memory and executive function did not. Baseline hippocampal atrophy was associated with increasing atrophy rates (hippocampal volume: p = 0.025; MTA score: p = 0.008); in contrast, WBV, WMH, and lacunes, adjusted for age and sex, were not significantly associated with hippocampal atrophy rates. CONCLUSIONS: In mild cognitive impairment (MCI), older age, poorer general cognition, hippocampal atrophy, and APOE epsilon 4 predict subsequent accelerated rates of hippocampal atrophy, suggestive of the accumulation of Alzheimer-type pathology, which may become clinically manifest in the future. These markers may improve identification of subjects with MCI at risk for Alzheimer disease.


Asunto(s)
Enfermedad de Alzheimer/patología , Atrofia/patología , Trastornos del Conocimiento/patología , Hipocampo/patología , Factores de Edad , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/fisiopatología , Apolipoproteína E4/genética , Atrofia/etiología , Atrofia/prevención & control , Biomarcadores/análisis , Inhibidores de la Colinesterasa/farmacología , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/fisiopatología , Estudios de Cohortes , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Estudios de Seguimiento , Galantamina/farmacología , Predisposición Genética a la Enfermedad/genética , Hipocampo/efectos de los fármacos , Hipocampo/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/patología , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Pronóstico
16.
Neuroimage ; 34(3): 1036-41, 2007 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-17174572

RESUMEN

MRI-derived rates of hippocampal atrophy may serve as surrogate markers of disease progression in mild cognitive impairment (MCI). Manual delineation is the gold standard in hippocampal volumetry; however, this technique is time-consuming and subject to errors. We aimed to compare regional non-linear (fluid) registration measurement of hippocampal atrophy rates against manual delineation in MCI. Hippocampi of 18 subjects were manually outlined twice on MRI scan-pairs (interval+/-SD: 2.01+/-0.11 years), and volumes were subtracted to calculate change over time. Following global affine and local rigid registration, regional fluid registration was performed from which atrophy rates were derived from the Jacobian determinants over the hippocampal region. Atrophy rates as derived by fluid registration were computed using both forward (repeat onto baseline) and backward (baseline onto repeat) registration. Reliability for both methods and agreement between methods was assessed. Mean+/-SD hippocampal atrophy rates (%/year) derived by manual delineation were: left: 2.13+/-1.62; right: 2.36+/-1.78 and for regional fluid registration: forward: left: 2.39+/-1.68; right: 2.49+/-1.52 and backward: left: 2.21+/-1.51; right: 2.42+/-1.49. Mean hippocampal atrophy rates did not differ between both methods. Reliability for manual hippocampal volume measurements (cross-sectional) was high (intraclass correlation coefficient (ICC): baseline and follow-up, left and right, >0.99). However, the resulting ICC for manual measurements of hippocampal volume change (longitudinal) was considerably lower (left: 0.798; right: 0.850) compared with regional fluid registration (forward: left: 0.985; right: 0.988 and backward: left: 0.975; right: 0.989). We conclude that regional fluid registration is more reliable than manual delineation in assessing hippocampal atrophy rates, without sacrificing sensitivity to change. This method may be useful to quantify hippocampal volume change, given the reduction in operator time and improved precision.


Asunto(s)
Trastornos del Conocimiento/patología , Hipocampo/patología , Aumento de la Imagen/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Anciano , Algoritmos , Inteligencia Artificial , Atrofia/patología , Método Doble Ciego , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Neurology ; 66(2): 236-8, 2006 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-16434661

RESUMEN

Hippocampal atrophy is a marker of Alzheimer disease (AD). It remains unclear whether this holds true for younger patients as well. Hippocampal volume was measured on MRI scans of 103 clinically diagnosed AD patients and 73 controls (aged 51 to 85 years). Aging and AD were independently associated with smaller hippocampal volume. Both young and old AD patients have hippocampal atrophy abnormal for age. Age-dependent criteria for hippocampal atrophy, suggestive of AD, are needed.


Asunto(s)
Envejecimiento , Enfermedad de Alzheimer/diagnóstico , Hipocampo/patología , Imagen por Resonancia Magnética , Anciano , Anciano de 80 o más Años , Atrofia , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Neurobiol Aging ; 27(8): 1051-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16169126

RESUMEN

Clinical utility of magnetic resonance imaging (MRI) for the diagnosis and assessment of neurodegenerative diseases may depend upon the reliability of MRI measurements, especially when applied within a multicenter context. In the present study, we assessed the reliability of MRI through a phantom test at a total of eleven clinics. Performance and entry criteria were defined liberally in order to support generalizability of the results. For manual hippocampal volumetry, automatic segmentation of brain compartments and voxel-based morphometry, multicenter variability was assessed on the basis of MRIs of a single subject scanned at ten of the eleven sites. In addition, cranial MRI scans obtained from 73 patients with Alzheimer's disease (AD) and 76 patients with mild cognitive impairment were collected at subset of six centers to assess differences in grey matter volume. Results show that nine out of eleven centers tested met the reliability criteria of the phantom test, where two centers showed aberrations in spatial resolution, slice thickness and slice position. The coefficient of variation was 3.55% for hippocampus volumetry, 5.02% for grey matter, 4.87% for white matter and 4.66% for cerebrospinal fluid (CSF). The coefficient of variation was 12.81% (S.D.=9.06) for the voxel intensities within grey matter and 8.19% (S.D.=6.9) within white matter. Power analysis for the detection of a difference in the volumes of grey matter between AD and MCI patients across centers (d=0.42) showed that the total sample size needed is N=180. In conclusion, despite minimal inclusion criteria, the reliability of MRI across centers was relatively good.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Encéfalo/patología , Trastornos del Conocimiento/diagnóstico , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Femenino , Alemania , Humanos , Masculino , Países Bajos , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
J Neurol Neurosurg Psychiatry ; 77(4): 439-42, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16306153

RESUMEN

BACKGROUND: Hippocampal atrophy on magnetic resonance imaging (MRI) is an early characteristic of Alzheimer's disease. However, hippocampal atrophy may also occur in other dementias, such as frontotemporal lobar degeneration (FTLD). OBJECTIVE: To investigate hippocampal atrophy on MRI in FTLD and its three clinical subtypes, in comparison with Alzheimer's disease, using volumetry and a visual rating scale. METHODS: 42 patients with FTLD (17 frontotemporal dementia, 13 semantic dementia, and 12 progressive non-fluent aphasia), 103 patients with Alzheimer's disease, and 73 controls were included. Hippocampal volumetry and the easily applicable medial temporal lobe atrophy (MTA) rating scale were applied to assess hippocampal atrophy. RESULTS: Multivariate analysis of variance for repeated measures showed an effect of diagnostic group on hippocampal volume. There was a significant diagnosis by side (left v right) interaction. Both FTLD and Alzheimer's disease showed hippocampal atrophy compared with controls. Results of the visual MTA rating scale confirmed these findings. Within the FTLD subtypes there were marked differences in hippocampal atrophy. Frontotemporal dementia and semantic dementia showed bilateral hippocampal atrophy, and in semantic dementia the left hippocampus was smaller than in Alzheimer's disease. No significant hippocampal atrophy was detected in non-fluent progressive aphasia. CONCLUSIONS: Hippocampal atrophy is not only a characteristic of Alzheimer's disease but also occurs in FTLD. The three clinical subtypes of FTLD show different patterns of hippocampal atrophy.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Demencia/diagnóstico , Hipocampo/patología , Imagen por Resonancia Magnética , Anciano , Enfermedad de Alzheimer/complicaciones , Atrofia/complicaciones , Atrofia/patología , Demencia/complicaciones , Femenino , Humanos , Masculino
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