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Publicaciones científicas más recientes (desde 2010)

Autores: Sánchez-Orduz, L.; Pérez-Larraya, J. G. ; Grisanti, F; et al.
ISSN 2253-654X  Vol. 39  Nº 2  2020  págs. 92 - 95
Early immunotherapy is of paramount importance for a positive outcome in patients suffering acute encephalitis of autoimmune origin (AIE). A new approach for early diagnosis based on dinical presentation and complementary tests has been proposed, but not all these tests show positive findings in the first weeks. While common forms of AIE (anti-LGI-1 and anti-NMDAR antibodies) exhibit consistent 18Fluor-fluorodeoxiglucose (FDG-PET) patterns in many cases, the anti-Caspr2 form of AIE is infrequent and FDG-PET patterns have not been well characterized. In our experience, FDG-PET in anti-Caspr2 limbic encephalitis shows medial temporal hypermetabolism and diffuse cortical hypometabolism, even in the absence of findings in these tests. However, it is necessary to standardize PET image analysis by means of visual and voxel-based methods compared to normal databases to define the areas of pathological metabolism that may go unnoticed when using visual analysis exclusively.
Autores: Law, I. , (Autor de correspondencia); Albert, N. L.; Arbizu, Javier Ignacio; et al.
ISSN 1619-7070  Vol. 46  Nº 3  2019  págs. 540 - 557
These joint practice guidelines, or procedure standards, were developed collaboratively by the European Association of Nuclear Medicine (EANM), the Society of Nuclear Medicine and Molecular Imaging (SNMMI), the European Association of Neurooncology (EANO), and the working group for Response Assessment in Neurooncology with PET (PET-RANO). Brain PET imaging is being increasingly used to supplement MRI in the clinical management of glioma. The aim of these standards/guidelines is to assist nuclear medicine practitioners in recommending, performing, interpreting and reporting the results of brain PET imaging in patients with glioma to achieve a high-quality imaging standard for PET using FDG and the radiolabelled amino acids MET, FET and FDOPA. This will help promote the appropriate use of PET imaging and contribute to evidence-based medicine that may improve the diagnostic impact of this technique in neurooncological practice. The present document replaces a former version of the guidelines published in 2006 (Vander Borght et al. Eur J Nucl Med Mol Imaging. 33:1374-80, 2006), and supplements a recent evidence-based recommendation by the PET-RANO working group and EANO on the clinical use of PET imaging in patients with glioma (Albert et al. Neuro Oncol. 18:1199-208, 2016). The information provided should be taken in the context of local conditions and regulations.
Autores: Virginia Pérez-Grijalba; Arbizu, Javier Ignacio; Judith Romero; et al.
ISSN 1758-9193  Vol. 11  Nº 1  2019  págs. 96
BACKGROUND: To facilitate population screening and clinical trials of disease-modifying therapies for Alzheimer's disease, supportive biomarker information is necessary. This study was aimed to investigate the association of plasma amyloid-beta (Aß) levels with the presence of pathological accumulation of Aß in the brain measured by amyloid-PET. Both plasma Aß42/40 ratio alone or combined with an FDG-PET-based biomarker of neurodegeneration were assessed as potential AD biomarkers. METHODS: We included 39 cognitively normal subjects and 20 patients with mild cognitive impairment from the AB255 Study who had undergone PiB-PET scans. Total Aß40 and Aß42 levels in plasma (TP42/40) were quantified using ABtest kits. Subjects were dichotomized as Aß-PET positive or negative, and the ability of TP42/40 to detect Aß-PET positivity was assessed by logistic regression and receiver operating characteristic analyses. Combination of plasma Aß biomarkers and FDG-PET was further assessed as an improvement for brain amyloidosis detection and diagnosis classification. RESULTS: Eighteen (30.5%) subjects were Aß-PET positive. TP42/40 ratio alone identified Aß-PET status with an area under the curve (AUC) of 0.881 (95% confidence interval [CI]¿=¿0.779-0.982). Discriminating performance of TP42/40 to detect Aß-PET-positive subjects yielded sensitivity and specificity values at Youden's cutoff of 77.8% and 87.5%, respectively, with a positive predictive value of 0.732 and negative predictive value of 0.900. All these parameters improved after adjusting the model for significant covariates. Applying TP42/40 as the first screening tool in a sequential diagnostic work-up would reduce the number of Aß-PET scans by 64%. Combination of both FDG-PET scores and plasma Aß biomarkers was found to be the most accurate Aß-PET predictor, with an AUC of 0.965 (95% CI¿=¿0.913-0.100). CONCLUSIONS: Plasma TP42/40 ratio showed a relevant and significant potential as a screening tool to identify brain Aß positivity in preclinical and prodromal stages of Alzheimer's disease.
Autores: Diez Valle, Ricardo; Gállego, Jaime; et al.
Revista: PLOS ONE
ISSN 1932-6203  Vol. 14  Nº 6  2019  págs. e0217881
Background Hypofractionated radiation therapy is a feasible and safe treatment option in elderly and frail patients with glioblastoma. The aim of this study was to evaluate the effectiveness of hypofractionated radiation therapy with concurrent temozolomide in terms of feasibility and disease control in primary glioblastoma patients with poor prognostic factors other than advanced age, such as post-surgical neurological complications, high tumor burden, unresectable or multifocal lesions, and potential low treatment compliance due to social factors or rapidly progressive disease. Material and methods GTV included the surgical cavity plus disease visible in T1WI-MRI, FLAIR-MRI and in the MET-uptake. The CTV was defined as the GTV plus 1.5-2 cm margin; the PTV was the CTV+0.3 cm margin. Forty, fourty-five, and fifty grays in 15 fractions were prescribed to 95% of PTV, CTV, and GTV, respectively. Treatment was delivered using IMRT or the VMAT technique. Simultaneously, 75 mg/m(2)/day of temozolomide were administered. Results Between January 2010 and November 2017, we treated a total of 17 patients. The median age at diagnosis was 68-years; median KPS was 50-70%. MGMT-methylation status was negative in 5 patients, and 8 patients were IDH-wildtype. Eight of 18 patients were younger than 65-years. Median tumor volume was 26.95cc; median PTV volume was 322cc. Four lesions were unresectable; 6 patients underwent complete surgical resection. Median residual volume was 1.14cc. Progression-free survival was 60% at 6 months, 33% at 1-year and 13% at 2-years (median OS = 7 months). No acute grade 3-5 toxicities were documented. Symptomatic grade 3 radiation necrosis was observed in one patient. Conclusions Patients with poor clinical factors other than advanced age can be selected for hypofractionated radiotherapy. The OS and PFS rates obtained in our series are similar to those in patients treated with standard fractionation, assuring good treatment adherence, low rates of toxicity and probable improved cost-effectiveness.
Autores: Casanovas, M. M. ; Field, C.; Bello, P.; et al.
ISSN 1619-7070  Vol. 46  Nº Supl. 1  2019  págs. S93 - S93
Autores: Arbizu, Javier Ignacio; Lorenzo-Bosquet, C.; et al.
ISSN 1619-7070  Vol. 46  Nº SUPPL 1  2019  págs. S317 - S318
Autores: Grisanti, F; Morales, María Isabel; Rosales, Juan Jose; et al.
ISSN 1619-7070  Vol. 46  Nº SUPPL 1  2019  págs. S488 - S489
Autores: Mitjavila, M. ; Percovich, J. C. ; Pasin, M. C. P. ; et al.
ISSN 0028-3835  Vol. 108  Nº Supl. 1  2019  págs. 223 - 223
Autores: Walker, Z., (Autor de correspondencia); Gandolfo, F. ; Orini, S.; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1534 - 1545
There are no comprehensive guidelines for the use of FDG PET in the following three clinical scenarios: (1) diagnostic work-up of patients with idiopathic Parkinson's disease (PD) at risk of future cognitive decline, (2) discriminating idiopathic PD from progressive supranuclear palsy, and (3) identifying the underlying neuropathology in corticobasal syndrome. We therefore performed three literature searches and evaluated the selected studies for quality of design, risk of bias, inconsistency, imprecision, indirectness and effect size. Critical outcomes were the sensitivity, specificity, accuracy, positive/negative predictive value, area under the receiving operating characteristic curve, and positive/negative likelihood ratio of FDG PET in detecting the target condition. Using the Delphi method, a panel of seven experts voted for or against the use of FDG PET based on published evidence and expert opinion. Of 91 studies selected from the three literature searches, only four included an adequate quantitative assessment of the performance of FDG PET. The majority of studies lacked robust methodology due to lack of critical outcomes, inadequate gold standard and no head-to-head comparison with an appropriate reference standard. The panel recommended the use of FDG PET for all three clinical scenarios based on nonquantitative evidence of clinical utility. Despite widespread use of FDG PET in clinical practice and extensive research, there is still very limited good quality evidence for the use of FDG PET. However, in the opinion of the majority of the panellists, FDG PET is a clinically useful imaging biomarker for idiopathic PD and atypical parkinsonism associated with dementia.
Autores: Arbizu, Javier Ignacio, (Autor de correspondencia); Festari, C.; Altomare, D.; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1497 - 1508
We aim to report the quality of accuracy studies investigating the utility of [F-18]fluorodeoxyglucose (FDG)-PET in supporting the diagnosis of prodromal Alzheimer's Disease (AD), frontotemporal lobar degeneration (FTLD) and prodromal dementia with Lewy bodies (DLB) in mild cognitive impairment (MCI) subjects, and the corresponding recommendations made by a panel of experts. Seven panellist, four from the European Association of Nuclear Medicine, and three from the European Academy of Neurology, produced recommendations taking into consideration the incremental value of FDG-PET, as added on clinical-neuropsychological examination, to ascertain the aetiology of MCI (AD, FTLD or DLB). A literature search using harmonized population, intervention, comparison, and outcome (PICO) strings was performed, and an evidence assessment consistent with the European Federation of Neurological Societies guidance was provided. The consensual recommendation was achieved based on Delphi rounds. Fifty-four papers reported the comparison of interest. The selected papers allowed the identification of FDG patterns that characterized MCI due to AD, FTLD and DLB. While clinical outcome studies supporting the diagnosis of MCI due to AD showed varying accuracies (ranging from 58 to 100%) and varying areas under the receiver-operator characteristic curves (0.66 to 0.97), no respective data were identified for MCI due to FTLD or for MCI due to DLB. However, the high negative predictive value of FDG-PET and the existence of different disease-specific patterns of hypometabolism support the consensus recommendations for the clinical use of this imaging technique in MCI subjects. FDG-PET has clinical utility on a fair level of evidence in detecting MCI due to AD. Although promising also in detecting MCI due to FTLD and MCI due to DLB, more research is needed to ultimately judge the clinical utility of FDG-PET in these entities.
Autores: Nobili, F., (Autor de correspondencia); Festari, C. ; Altomare, D.; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1557 - 1566
To review literature until November 2015 and reach a consensus on whether automatic semi-quantification of brain FDG-PET is useful in the clinical setting for neurodegenerative disorders. A literature search was conducted in Medline, Embase, and Google Scholar. Papers were selected with a lower limit of 30 patients (no limits with autopsy confirmation). Consensus recommendations were developed through a Delphi procedure, based on the expertise of panelists, who were also informed about the availability and quality of evidence, assessed by an independent methodology team. Critical outcomes were available in nine among the 17 papers initially selected. Only three papers performed a direct comparison between visual and automated assessment and quantified the incremental value provided by the latter. Sensitivity between visual and automatic analysis is similar but automatic assessment generally improves specificity and marginally accuracy. Also, automated assessment increases diagnostic confidence. As expected, performance of visual analysis is reported to depend on the expertise of readers. Tools for semi-quantitative evaluation are recommended to assist the nuclear medicine physician in reporting brain FDG-PET pattern in neurodegenerative conditions. However, heterogeneity, complexity, and drawbacks of these tools should be known by users to avoid misinterpretation. Head-to-head comparisons and an effort to harmonize procedures are encouraged.
Autores: Verger, A., (Autor de correspondencia); Arbizu, Javier Ignacio; Law, I.;
ISSN 1824-4785  Vol. 62  Nº 3  2018  págs. 254 - 266
Positron emission tomography (PET) using radiolabeled amino-acids was recently recommended by the Response Assessment in Neuro-Oncology (RANO) working group as an additional tool in the diagnostic assessment of brain tumors. The aim of this review is to summarize available literature data on the role of amino-acid PET imaging in high-grade gliomas (HGGs), with regard to diagnosis, treatment planning and follow-up of these tumors. Indeed, amino-acid PET applications are multiple throughout the evolution of HGGs. However, certain limitations such as lack of specificity, uncertain value for grading and prognostication or the limited data for treatment monitoring should to be taken into account, the latter of which are further developed in this review. Notwithstanding these limitations, amino-acid PET is becoming increasingly accessible in many nuclear medicine centers. Larger prospective cohort prospective studies are thus needed in order to increase the clinical value of this modality and enable its extended use to the largest number of patients.
Autores: Drzezga, A. , (Autor de correspondencia); Altomare, D.; Festari, C. ; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1487 - 1496
To assess the clinical utility of 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET) for detection of early signs of neurodegeneration in conditions of increased risk for Alzheimer's disease (AD) as defined by: subjective cognitive decline (SCD), evidence of cerebral amyloid-pathology, apolipoprotein E (APOE) epsilon 4-positive genotype, or autosomal dominant forms of AD (ADAD) in asymptomatic stages. A comprehensive literature search was conducted using the PICO model to extract evidence from relevant studies. An expert panel then voted using the Delphi method on three different diagnostic scenarios. The level of empirical study evidence for the use of FDG-PET to detect meaningful early signs of neurodegeneration was considered to be poor for ADAD and lacking for SCD and asymptomatic persons at risk, based on APOE epsilon 4-positive genotype or cerebral amyloid pathology. Consequently, and consistent with current diagnostic criteria, panelists decided not to recommend routine clinical use of FDG-PET in these situations and to currently mainly reserve it for research purposes. Currently, there is limited evidence on which to base recommendations regarding the clinical routine use of FDG-PET to detect diagnostically meaningful early signs of neurodegeneration in asymptomatic subjects with ADAD, with APOE epsilon 4-positive genotype, or with cerebral amyloid pathology, and in subjects with SCD. Future prospective studies are warranted and in part already ongoing, aiming to assess the added value of FDG-PET in this context beyond research applications.
Autores: Bouwman, F. , (Autor de correspondencia); Orini, S.; Gandolfo, F.; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1526 - 1533
A joint effort of the European Association of Nuclear Medicine (EANM) and the European Academy of Neurology (EAN) aims at clinical guidance for the use of FDG-PET in neurodegenerative diseases. This paper addresses the diagnostic utility of FDG-PET over clinical/neuropsychological assessment in the differentiation of the three forms of primary progressive aphasia (PPA). Seven panelists were appointed by the EANM and EAN and a literature search was performed by using harmonized PICO (Population, Intervention, Comparison, Outcome) question keywords. The studies were screened for eligibility, and data extracted to assess their methodological quality. Critical outcomes were accuracy indices in differentiating different PPA clinical forms. Subsequently Delphi rounds were held with the extracted data and quality assessment to reach a consensus based on both literature and expert opinion. Critical outcomes for this PICO were available in four of the examined papers. The level of formal evidence supporting clinical utility of FDG-PET in differentiating among PPA variants was considered as poor. However, the consensual recommendation was defined on Delphi round I, with six out of seven panelists supporting clinical use. Quantitative evidence demonstrating utility or lack thereof is still missing. Panelists decided consistently to provide interim support for clinical use based on the fact that a typical atrophy or metabolic pattern is needed for PPA according to the diagnostic criteria, and the synaptic failure detected by FDG-PET is an earlier phenomenon than atrophy. Also, a normal FDG-PET points to a non-neurodegenerative cause.
Autores: Camacho, V., (Autor de correspondencia); Gomez-Grande, A.; Sopena, P.; et al.
ISSN 2253-654X  Vol. 37  Nº 6  2018  págs. 397 - 406
Alzheimer's disease (AD) is a neurodegenerative condition characterized by progressive cognitive decline and memory loss, and is the most common form of dementia. Amyloid plaques with neurofibrillary tangles are a neuropathological hallmark of AD that produces synaptic dysfunction and culminates later in neuronal loss. Amyloid PET is a useful, available and non-invasive technique that provides in vivo information about the cortical amyloid burden. In the latest revised criteria for the diagnosis of AD biomarkers were defined and integrated: pathological and diagnostic biomarkers (increased retention on fibrillar amyloid PET or decreased A beta(1-42) and increased T-Tau or P-Tau in CSF) and neurodegeneration or topographical biomarkers (temporoparietal hypometabolism on F-18-FDG PET and temporal atrophy on MRI). Recently specific recommendations have been created as a consensus statement on the appropriate use of the imaging biomarkers, including amyloid PET: early-onset cognitive impairment/dementia, atypical forms of AD, mild cognitive impairment with early age of onset, and to differentiate between AD and other neurodegenerative diseases that occur with dementia. Amyloid PET is also contributing to the development of new therapies for AD, as well as in research studies for the study of other neurodegenerative diseases that occur with dementia where the deposition of A beta amyloid is involved in its pathogenesis. In this paper, we review some general concepts and study the use of amyloid PET in depth and its relationship with neurodegenerative diseases and other diagnostic techniques.
Autores: Nestor, P. J., (Autor de correspondencia); Altomare, D.; Festari, C. ; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1509 - 1525
To assess the clinical utility of FDG-PET as a diagnostic aid for differentiating Alzheimer's disease (AD; both typical and atypical forms), dementia with Lewy bodies (DLB), frontotemporal lobar degeneration (FTLD), vascular dementia (VaD) and non-degenerative pseudodementia. A comprehensive literature search was conducted using the PICO model to extract evidence from relevant studies. An expert panel then voted on six different diagnostic scenarios using the Delphi method. The level of empirical study evidence for the use of FDG-PET was considered good for the discrimination of DLB and AD; fair for discriminating FTLD from AD; poor for atypical AD; and lacking for discriminating DLB from FTLD, AD from VaD, and for pseudodementia. Delphi voting led to consensus in all scenarios within two iterations. Panellists supported the use of FDG-PET for all PICOs-including those where study evidence was poor or lacking-based on its negative predictive value and on the assistance it provides when typical patterns of hypometabolism for a given diagnosis are observed. Although there is an overall lack of evidence on which to base strong recommendations, it was generally concluded that FDG-PET has a diagnostic role in all scenarios. Prospective studies targeting diagnostically uncertain patients for assessing the added value of FDG-PET would be highly desirable.
Autores: Merino-Casabiel, X.; Aller, J.; Arbizu, Javier Ignacio; et al.
ISSN 1699-048X  Vol. 20  Nº 12  2018  págs. 1522 - 1528
PurposeGastroenteropancreatic neuroendocrine tumors are a heterogeneous group of low incidence neoplasms characterized by a low proliferative activity and slow growth. Their response to targeted therapies is heterogeneous and often does not lead to tumor shrinkage. Thus, evaluation of the therapeutic response should differ from other kind of tumors.MethodsTo answer relevant questions about which techniques are best in the assessment of progression or treatment response a RAND/UCLA-based consensus process was implemented. Relevant clinical questions were listed followed by a systematic search of the literature. The expert panel answered all questions with recommendations, combining available evidence and expert opinion. Recommendations were validated through a questionnaire and a participatory meeting.ResultsExpert recommendations regarding imaging tools for tumor assessment and evaluation of progression were agreed upon. Available imaging techniques were reviewed and recommendations for best patient monitoring practice and the best way to evaluate treatment response were formulated.
Autores: Agosta, F., (Autor de correspondencia); Altomare, D.; Festari, C.; et al.
ISSN 1619-7070  Vol. 45  Nº 9  2018  págs. 1546 - 1556
To evaluate the incremental value of FDG-PET over clinical tests in: (i) diagnosis of amyotrophic lateral sclerosis (ALS); (ii) picking early signs of neurodegeneration in patients with a genetic risk of Huntington's disease (HD); and detecting metabolic changes related to cognitive impairment in (iii) ALS and (iv) HD patients. Four comprehensive literature searches were conducted using the PICO model to extract evidence from relevant studies. An expert panel then voted using the Delphi method on these four diagnostic scenarios. The availability of evidence was good for FDG-PET utility to support the diagnosis of ALS, poor for identifying presymptomatic subjects carrying HD mutation who will convert to HD, and lacking for identifying cognitive-related metabolic changes in both ALS and HD. After the Delphi consensual procedure, the panel did not support the clinical use of FDG-PET for any of the four scenarios. Relative to other neurodegenerative diseases, the clinical use of FDG-PET in ALS and HD is still in its infancy. Once validated by disease-control studies, FDG-PET might represent a potentially useful biomarker for ALS diagnosis. FDG-PET is presently not justified as a routine investigation to predict conversion to HD, nor to detect evidence of brain dysfunction justifying cognitive decline in ALS and HD.
Autores: Nobili, F. , (Autor de correspondencia); Arbizu, Javier Ignacio; Bouwman, F.; et al.
ISSN 1351-5101  Vol. 25  Nº 10  2018  págs. 1201 - 1217
Background and purposeRecommendations for using fluorodeoxyglucose positron emission tomography (FDG-PET) to support the diagnosis of dementing neurodegenerative disorders are sparse and poorly structured. MethodsTwenty-one questions on diagnostic issues and on semi-automated analysis to assist visual reading were defined. Literature was reviewed to assess study design, risk of bias, inconsistency, imprecision, indirectness and effect size. Critical outcomes were sensitivity, specificity, accuracy, positive/negative predictive value, area under the receiver operating characteristic curve, and positive/negative likelihood ratio of FDG-PET in detecting the target conditions. Using the Delphi method, an expert panel voted for/against the use of FDG-PET based on published evidence and expert opinion. ResultsOf the 1435 papers, 58 papers provided proper quantitative assessment of test performance. The panel agreed on recommending FDG-PET for 14 questions: diagnosing mild cognitive impairment due to Alzheimer's disease (AD), frontotemporal lobar degeneration (FTLD) or dementia with Lewy bodies (DLB); diagnosing atypical AD and pseudo-dementia; differentiating between AD and DLB, FTLD or vascular dementia, between DLB and FTLD, and between Parkinson's disease and progressive supranuclear palsy; suggesting underlying pathophysiology in corticobasal degeneration and progressive primary aphasia, and cortical dysfunction in Parkinson's disease; using semi-automated assessment to assist visual reading. Panellists did not support FDG-PET use for pre-clinical stages of neurodegenerative disorders, for amyotrophic lateral sclerosis and Huntington disease diagnoses, and for amyotrophic lateral sclerosis or Huntington-disease-related cognitive decline. ConclusionsDespite limited formal evidence, panellists deemed FDG-PET useful in the early and differential diagnosis of the main neurodegenerative disorders, and semi-automated assessment helpful to assist visual reading. These decisions are proposed as interim recommendations.
Autores: Casanovas, M. M. ; Percovich, J.; Bello, P. ; et al.
ISSN 1619-7070  Vol. 45  Nº Supl. 1  2018  págs. S593 - S594
Autores: Casanovas, M. M. ; Percovich, J. ; Bello, P.; et al.
ISSN 1619-7070  Vol. 45  Nº Supl. 1  2018  págs. S594
Autores: Morales, María Isabel; Grisanti, F; et al.
ISSN 1619-7070  Vol. 45  Nº Supl. 1  2018  págs. S88 - S89
Autores: Garcia-Consuegra, A.; et al.
ISSN 1522-8517  Vol. 20  Nº Supl. 3  2018  págs. 253 - 253
Autores: Prieto, Elena; Aguilar Redondo, P. B.; Morán, Verónica; et al.
ISSN 1619-7070  Vol. 45  Nº Supl. 1  2018  págs. S312 - S313
Autores: Guillen Valderrama, E; Perez-Grijalba, V.; Prieto, Elena; et al.
ISSN 1619-7070  Vol. 45  Nº Supl. 1  2018  págs. S227 - S228
Autores: Morbelli, S.; Arbizu, Javier Ignacio; Booij, J.; et al.
ISSN 1619-7070  Vol. 44  Nº 3  2017  págs. 559 - 560
Autores: Arbizu, Javier Ignacio, (Autor de correspondencia); Giuliani, A.; Gállego, Jaime; et al.
ISSN 1824-4785  Vol. 61  Nº 4  2017  págs. 386 - 404
PET using F-18-2-fluoro-2-deoxy-D-glucose (FDG-PET) has been gradually introduced in the diagnostic clinical criteria of the most prevalent neurodegenerative diseases. Moreover, an increasing amount of literature has shown that the information provided by FDG-PET enhances the sensitivity of standard imaging biomarkers in less frequent disorders in which an early differential diagnosis can be of paramount relevance for patient management and outcome. Therefore emerging uses of FDG-PET may be important in prion diseases, autoimmune encephalitis (AE) and amyotrophic lateral sclerosis. Interestingly, FDG-PET findings can also be observed in the early phases of these conditions, even in the presence of normal magnetic resonance imaging scans. Thalamic hypometabolism is a common finding in sporadic Creutzfeldt-Jacob disease and fatal familiar insomnia patients, with further cortical synaptic dysfunction in the former. Limbic and extra-limbic metabolic abnormalities (more often hypermetabolism) can be observed in AE, although specific patterns may be seen within different syndromes associated with antibodies that target neuronal surface or synaptic antigens. FDG-PET shows its usefulness by discriminating patients with amyotrophic lateral sclerosis associated to upper motor neuron onset that evolve to frontotemporal dementia. Besides visual and voxel based image analysis, multivariate analysis as interregional correlation analysis and independent/principal component analysis have been successfully implemented to PET images increasing the accuracy of the discrimination of neurodegenerative diseases. The clinical presentation and current diagnostic criteria of these neurologic disorders as well as the emerging usefulness of FDG-PET in the diagnostic workup are presented and discussed in this review.
Autores: Arbizu, Javier Ignacio;
ISSN 2253-654X  Vol. 36  Nº 1  2017  págs. 1
Autores: Morbelli, S.; Arbizu, Javier Ignacio; Booij, J.; et al.
ISSN 1619-7070  Vol. 44  Nº 3  2017  págs. 353 - 57
Autores: Garcia-Ribas, G.; Arbizu, Javier Ignacio; Carrio, I; et al.
ISSN 0213-4853  Vol. 32  Nº 5  2017  págs. 275 - 277
Autores: Marti-Climent, JM; Prieto, Elena; Morán, Verónica; et al.
ISSN 2191-219X  Vol. 7  Nº 1  2017  págs. 37
The mean ED for body and brain PET/CT protocols with different radiopharmaceuticals ranged between 4.6 and 20.0 mSv. The major contributor to total ED for body protocols is CT, whereas for brain studies, it is the PET radiopharmaceutical.
Autores: Balsa, M. A. ; Camacho, V.; Garrastachu, P.; et al.
ISSN 2253-654X  Vol. 36  Nº 4  2017  págs. 219 - 226
Objective: To determine the status of neuroimaging studies of Nuclear Medicine in Spain during 2013 and first quarter of 2014, in order to define the activities of the neuroimaging group of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). Material and methods: A questionnaire of 14 questions was designed, divided into 3 parts: characteristics of the departments (equipment and professionals involved); type of scans and clinical indications; and evaluation methods. The questionnaire was sent to 166 Nuclear Medicine departments. Results: A total of 54 departments distributed among all regions completed the questionnaire. Most departments performed between 300 and 800 neuroimaging examinations per year, representing more than 25 scans per month. The average pieces of equipment were three; half of the departments had a PET/CT scanner and SPECT/CT equipment. Scans performed more frequently were brain SPECT with I-123-FP-CIT, followed by brain perfusion SPECT and PET with F-18-FDG. The most frequent clinical indications were cognitive impairment followed by movement disorders. For evaluation of the images most sites used only visual assessment, and for the quantitative assessment the most used was quantification by region of interest. Conclusions: These results reflect the clinical activity of 2013 and first quarter of 2014. The main indications of the studies were cognitive impairment and movement disorders. Variability in the evaluation of the studies is among the challenges that will be faced in the coming years. (C) 2017 Elsevier Espana, S.L.U. y SEMNIM. All rights reserved.
Autores: Boccardi, M. ; Festari, C. ; Arbizu, Javier Ignacio; et al.
ISSN 1351-5101  Vol. 24  Nº Supl 1  2017  págs. 447 - 448
Autores: Arbizu, Javier Ignacio; Danilenko, A.; Guillen Valderrama, E; et al.
ISSN 1619-7070  Vol. 43  Nº Supl.1  2016  págs. S118 - S118
Autores: Sancho, Lidia; Rodríguez-Fraile, M; Prieto, Elena; et al.
ISSN 1619-7070  Vol. 43  Nº Suppl. 1  2016  págs. S12 - S12
Autores: Arbizu, Javier Ignacio; Irimia, Pablo; et al.
ISSN 0363-9762  Vol. 40  Nº 9  2015  págs. e441-43
A 70-year-old woman with a history of autoimmune hepatitis and renal cell carcinoma presented with subacute cognitive impairment. A brain MRI revealed mild leukoaraiosis, whereas brain F-FDG PET/CT showed diffuse cerebral hypometabolism that resembled some of the patterns described in limbic encephalitis and neurodegenerative diseases. With the suspicion of autoimmune encephalitis, the patient received immunotherapy with dramatic improvement of cognitive function and metabolic normalization at the 2-month follow-up on brain F-FDG PET/CT. Our results demonstrate that brain F-FDG PET/CT might be a useful tool in the assessment of patients with autoimmune encephalitis.
Autores: Cardier, M; Zulueta-Santos, Cristina; Manrique, Raquel; et al.
ISSN 1420-3030  Vol. 20  Nº Supl 1  2015  págs. 48 - 52
This article presents an analysis of the impact of functional neuroimaging studies (positron emission tomography, PET) in asymmetric hearing loss based on the clinical expertise obtained from a group of 21 patients. In these patients, PET studies are performed at rest and after auditory stimulation in order to measure the increase in brain activity in the ipsi- and contralateral cortex, providing supporting evidence to recommend a specific treatment and the side to implant. In conclusion, PET is a useful tool for selected cases in which information on the metabolic status of the auditory pathway can drive the decision regarding the treatment of the most appropriate ear. However, in view of our small sample, further research is needed to confirm our results in this topic
Autores: Prieto, Elena; Marti-Climent, JM; Morán, Verónica; et al.
ISSN 1120-1797  Vol. 31  Nº 8  2015  págs. 948-955
Optimization of reconstruction algorithm and parameters has been performed to take particular advantage of the last generation PET scanner, recommending specific settings for different brain PET radiotracers.
Autores: P. Tellechea; N. Pujol; Esteve, Patricia; et al.
ISSN 0213-4853  Vol. 33  Nº 4  2015  págs. 244-253
Early-onset Alzheimer disease (EOAD), which presents in patients younger than 65 years, has frequently been described as having different features from those of late-onset Alzheimer disease (LOAD). This review analyses the most recent studies comparing the clinical presentation and neuropsychological, neuropathological, genetic, and neuroimaging findings of both types in order to determine whether EOAD and LOAD are different entities or distinct forms of the same entity. We observed consistent differences between clinical findings in EOAD and in LOAD. Fundamentally, the onset of EOAD is more likely to be marked by atypical symptoms, and cognitive assessments point to poorer executive and visuospatial functioning and praxis with less marked memory impairment. Alzheimer-type features will be more dense and widespread in neuropathology studies, with structural and functional neuroimaging showing greater and more diffuse atrophy extending to neocortical areas (especially the precuneus). In conclusion, available evidence suggests that EOAD and LOAD are 2 different forms of a single entity. LOAD is likely to be influenced by ageing-related processes.
Autores: Prieto, Elena; Riverol, M.; et al.
ISSN 1619-7070  Vol. 42  Nº 10  2015  págs. 1522-9
Patients with a prion disease exhibit a characteristic pattern of brain metabolism presentation in FDG PET imaging. Consequently, in patients with rapidly progressive cognitive impairment, the detection of these patterns in the FDG PET study could orient the diagnosis to a prion disease.
Autores: Sancho, Lidia; Morán, Verónica; et al.
ISSN 2253-8070  Vol. 34  Nº Supl. 1  2015  págs. 59
La evaluación clínica del PET de amiloide con 18 F-florbetapir no se afecta por el tipo de equipo, aunque los de nueva generación reducen el número de casos dudosos. Para el seguimiento, los estudios deben ser adquiridos en un tiempo de adquisición similar. Estos hallazgos son relevantes para los ensayos de posibles nuevos fármacos anti-amiloid
Autores: Luquin, María Rosario Isabel; et al.
ISSN 0213-4853  Vol. 30  Nº 3  2014  págs. 144 - 152
Introducción Las prionopatías representan hasta el 62% de los casos de demencia rápidamente progresiva (DRP) en los que se alcanza un diagnóstico definitivo. La variabilidad de los síntomas y signos iniciales y las diferencias en su evolución dificultan el diagnóstico precoz. Métodos Estudio retrospectivo en el que se incluye a pacientes con prionopatía probable o definitiva, que acudieron a la consulta de Neurología de nuestro centro durante el periodo 1999-2012. Se describen las características clínicas y los resultados de las exploraciones complementarias (proteína 14-3-3, EEG, RM, PET-FDG y análisis genético), con la finalidad de identificar qué marcadores permiten un diagnóstico precoz. Resultados Se describe a 14 pacientes: 6 con enfermedad de Creutzfeldt-Jakob esporádica (ECJe) definitiva, 3 con ECJe probable, 4 con insomnio familiar fatal y uno con la nueva variante de la enfermedad de Creutzfeldt-Jakob. La mediana de edad al diagnóstico fue de 54 años y la mediana de supervivencia de 9,5 meses. El trastorno del ánimo fue el síntoma inicial más frecuente, seguido de inestabilidad de la marcha y deterioro cognitivo. La proteína 14-3-3 fue positiva en el líquido cefalorraquídeo en 7 de 11 pacientes y el EEG mostró signos típicos en 2 de 12 pacientes explorados. El estudio de neuroimagen mostró alteraciones en 13 de los 14 pacientes. Conclusiones Además de la DRP, el trastorno conductual y de la marcha son síntomas iniciales frecuentes en las prionopatías. En nuestra serie, las pruebas complementarias más útiles para apoyar el diagnóstico fueron la RM y la PET-FDG.
Autores: Riverol, M.; Collantes M; DiCaudo C; et al.
ISSN 0969-9961  Vol. 62  2014  págs. 250-259
Much controversy exists concerning the effect of levodopa on striatal dopaminergic markers in Parkinson's disease (PD) and its influence on functional neuroimaging. To deal with this issue we studied the impact of neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and chronic levodopa administration on striatal (18)F-DOPA uptake (Ki) in an animal model of PD. The levels of several striatal dopaminergic markers and the number of surviving dopaminergic neurons in the substantia nigra (SN) were also assessed. Eleven Macaca fascicularis were included in the study. Eight animals received weekly intravenous injections of MPTP for 7weeks and 3 intact animals served as controls. MPTP-monkeys were divided in two groups. Group I was treated with placebo while Group II received levodopa. Both treatments were maintained for 11months and then followed by a washout period of 6months. (18)F-DOPA positron emission tomography (PET) scans were performed at baseline, after MPTP intoxication, following 11months of treatment, and after a washout period of 1, 3 and 6months. Monkeys were sacrificed 6months after concluding either placebo or levodopa treatment and immediately after the last (18)F-DOPA PET study. Striatal dopamine transporter (DAT) content, tyrosine hydroxylase (TH) content and aromatic l-amino acid decarboxylase (AADC) content were assessed. In Group II (18)F-DOPA PET studies performed at 3 and 6months after interrupting levodopa showed a significantly increased Ki in the anterior putamen as compared to Group I. Levodopa and placebo treated animals exhibited a similar number of surviving dopaminergic cells in the SN. Striatal DAT content was equally reduced in both groups of animals. Animals in Group I exhibited a significant decrease in TH protein content in all the striatal regions assessed. However, in Group II, TH levels were significantly reduced only in the anterior and posterior putamen. Surprisingly, in the levodopa-treated animals the TH levels in the posterior putamen were significantly lower than those in the placebo group. AADC levels in MPTP groups were similar to those of control animals in all striatal areas analyzed. This study shows that chronic levodopa administration to monkeys with partial nigrostriatal degeneration followed by a washout period induces modifications in the functional activity of the dopaminergic nigrostriatal pathway.
Autores: Garrido, V.; Collantes M; Barberán, M.; et al.
ISSN 0066-4804  Vol. 58  Nº 11  2014  págs. 6660 - 6667
A mouse model was developed for in vivo monitoring of infection and the effect of antimicrobial treatment against Staphylococcus aureus biofilms, using the [(18)F]fluoro-deoxyglucose-MicroPET ([(18)F]FDG-MicroPET) image technique. In the model, sealed Vialon catheters were briefly precolonized with S. aureus strains ATCC 15981 or V329, which differ in cytotoxic properties and biofilm matrix composition. After subcutaneous implantation of catheters in mice, the S. aureus strain differences found in bacterial counts and the inflammatory reaction triggered were detected by the regular bacteriological and histological procedures and also by [(18)F]FDG-MicroPET image signal intensity determinations in the infection area and regional lymph node. Moreover, [(18)F]FDG-MicroPET imaging allowed the monitoring of the rifampin treatment effect, identifying the periods of controlled infection and those of reactivated infection due to the appearance of bacteria naturally resistant to rifampin. Overall, the mouse model developed may be useful for noninvasive in vivo determinations in studies on S. aureus biofilm infections and assessment of new therapeutic approaches.
Autores: Marti-Climent, JM; Prieto, Elena; Elosúa C; et al.
ISSN 0094-2405  Vol. 41  Nº 9  2014  págs. 092503
Qualitative and quantitative 90Y PET imaging improved with the introduction of TOF in a PET/CT scanner, thereby allowing the visualization of microsphere deposition in lesions not visible in non-TOF images. This technique accurately quantifies the total activity delivered to the liver during radioembolization with (90)Y-microspheres and allows dose estimation.
Autores:  et al.
Revista: BRAIN
ISSN 0006-8950  Vol. 137  Nº PT 8  2014  págs. 2356-7
The pathophysiological process underlying cognitive decline in Parkinson's disease is not well understood. Cerebral atrophy and hypometabolism have been described in patients with Parkinson's disease and dementia or mild cognitive impairment with respect to control subjects. However, the exact relationships between atrophy and hypometabolism are still unclear. To determine the extension and topographical distribution of hypometabolism and atrophy in the different cognitive states of Parkinson's disease, we examined 46 patients with Parkinson's disease (19 female, 27 male; 71.7 ± 5.9 years old; 14.6 ± 4.2 years of disease evolution; modified Hoehn and Yahr mean stage 3.1 ± 0.7). Cognitive status was diagnosed as normal in 14 patients, as mild cognitive impairment in 17 and as dementia in 15 patients. Nineteen normal subjects (eight female, 11 male; 68.1 ± 3.2 years old) were included as controls. (18)F-fluorodeoxyglucose positron emission tomography and magnetic resonance imaging scans were obtained, co-registered, corrected for partial volume effect and spatially normalized to the Montreal Neurological Institute space in each subject. Smoothing was applied to the positron emission tomography and magnetic resonance imaging scans to equalize their effective smoothness and resolution (10 mm and 12 mm full-width at half-maximum and Gaussian kernel, respectively). Z-score maps for atrophy and for hypometabolism were obtained by comparing individual images to the data set of contro
Autores: Luquin, María Rosario Isabel; et al.
ISSN 0213-4853  Vol. 28  Nº 5  2013  págs. 299-308
Autores: Arbizu, Javier Ignacio; Prieto, Elena; et al.
ISSN 1619-7070  Vol. 10  Nº 9  2013  págs. 1394 - 1405
To introduce, evaluate and validate a voxel-based analysis method of F-18-FDG PET imaging for determining the probability of Alzheimer's disease (AD) in a particular individual. The subject groups for model derivation comprised 80 healthy subjects (HS), 36 patients with mild cognitive impairment (MCI) who converted to AD dementia within 18 months, 85 non-converter MCI patients who did not convert within 24 months, and 67 AD dementia patients with baseline FDG PET scan were recruited from the AD Neuroimaging Initiative (ADNI) database. Additionally, baseline FDG PET scans from 20 HS, 27 MCI and 21 AD dementia patients from our institutional cohort were included for model validation. The analysis technique was designed on the basis of the AD-related hypometabolic convergence index adapted for our laboratory-specific context (AD-PET index), and combined in a multivariable model with age and gender for AD dementia detection (AD score). A logistic regression analysis of different cortical PET indexes and clinical variables was applied to search for relevant predictive factors to include in the multivariable model for the prediction of MCI conversion to AD dementia (AD-Conv score). The resultant scores were stratified into sixtiles for probabilistic diagnosis. The area under the receiver operating characteristic curve (AUC) for the AD score detecting AD dementia in the ADNI database was 0.879, and the observed probability of AD dementia in the six defined groups ranged from 8 % to 100 % in a monotonic trend. For predicting MCI conversion to AD dementia, only the posterior cingulate index, Mini-Mental State Examination (MMSE) score and apolipoprotein E4 genotype (ApoE4) exhibited significant independent effects in the univariable and multivariable models. When only the latter two clinical variables were included in the model, the AUC was 0.742 (95 % CI 0.646 - 0.838), but this increased to 0.804 (95 % CI 0.714 - 0.894, bootstrap p = 0.027) with the addition of the posterior cingulate index (AD-Conv score). Baseline clinical diagnosis of MCI showed 29.7 % of converters after 18 months. The observed probability of conversion in relation to baseline AD-Conv score was 75 % in the high probability group (sixtile 6), 34 % in the medium probability group (merged sixtiles 4 and 5), 20 % in the low probability group (sixtile 3) and 7.5 % in the very low probability group (merged sixtiles 1 and 2). In the validation population, the AD score reached an AUC of 0.948 (95 % CI 0.625 - 0.969) and the AD-Conv score reached 0.968 (95 % CI 0.908 - 1.000), with AD patients and MCI converters included in the highest probability categories. Posterior cingulate hypometabolism, when combined in a multivariable model with age and gender as well as MMSE score and ApoE4 data, improved the determination of the likelihood of patients with MCI converting to AD dementia compared with clinical variables alone. The probabilistic model described here provides a new tool that may aid in the clinical diagnosis of AD and MCI conversion.
Autores: Marti-Climent, JM; Prieto, Elena; et al.
ISSN 0212-6982  Vol. 32  Nº 1  2013  págs. 13 - 21
Objective: To characterize the performance of the Biograph mCT PET/CT TrueV scanner with time of flight (TOF) and point spread function (PSF) modeling. Material and methods: The PET/CT scanner combines a 64-slice CT and PET scanner that incorporates in the reconstruction the TOF and PSF information. PET operating characteristics were evaluated according to the standard NEMA NU 2-2007, expanding some tests. In addition, different reconstruction algorithms were included, and the intrinsic radiation and tomographic uniformity were also evaluated. Results: The spatial resolution (FWHM) at 1 and 10 cm was 4.4 and 5.3 mm, improving to 2.6 and 2.5 mm when PSF is introduced. Sensitivity was 10.9 and 10.2 Kcps/MBq at 0 and 10 cm from the axis. Scatter fraction was less than 34% at low concentrations and the noise equivalent count rate (NECR) was maximal at 27.8 kBq/mL with 182 Kcps, the intrinsic radiation produced a rate of 4.42 true coincidences per second. Coefficient of variation of the volume and system uniformity were 4.7 and 0.8% respectively. The image quality test showed better results when PSF and TOF were included together. PSF improved the hot spheres contrast and background variability, while TOF improved the cold spheres contrast. Conclusions: The Biograph mCT TrueV scanner has good performance characteristics. The image quality improves when the information from the PSF and the TOF is incorporated in the reconstruction.
Autores: Arbizu, Javier Ignacio; Tejada, Sonia; Marti-Climent, JM; et al.
ISSN 1619-7070  Vol. 39  Nº 5  2012  págs. 771 - 781
PURPOSE: The aim of the study was to evaluate the volumetric integration patterns of standard MRI and (11)C-methionine positron emission tomography (PET) images in the surgery planning of gliomas and their relationship to the histological grade. METHODS: We studied 23 patients with suspected or previously treated glioma who underwent preoperative (11)C-methionine PET because MRI was imprecise in defining the surgical target contour. Images were transferred to the treatment planning system, coregistered and fused (BrainLAB). Tumour delineation was performed by (11)C-methionine PET thresholding (vPET) and manual segmentation over MRI (vMRI). A 3-D volumetric study was conducted to evaluate the contribution of each modality to tumour target volume. All cases were surgically treated and histological classification was performed according to WHO grades. Additionally, several biopsy samples were taken according to the results derived either from PET or from MRI and analysed separately. RESULTS: Fifteen patients had high-grade tumours [ten glioblastoma multiforme (GBM) and five anaplastic), whereas eight patients had low-grade tumours. Biopsies from areas with high (11)C-methionine uptake without correspondence in MRI showed tumour proliferation, including infiltrative zones, distinguishing them from dysplasia and radionecrosis. Two main PET/MRI integration patterns emerged after analysis of volumetric data: pattern vMRI-in-vPET (11/23) and pattern vPET-in-vMRI (9/23). Besides, a possible third pattern with differences in both directions (vMRI-diff-vPET) could also be observed (3/23). There was a statistically significant association between the tumour classification and integration patterns described above (p¿<¿0.001, ¿¿=¿0.72). GBM was associated with pattern vMRI-in-vPET (9/10), low-grade with pattern vPET-in-vMRI (7/8) and anaplastic with pattern vMRI-diff-vPET (3/5). CONCLUSION: The metabolically active tumour volume observed in (11)C-methionine PET differs from the volume of MRI by showing areas of infiltrative tumour and distinguishing from non-tumour lesions. Differences in (11)C-methionine PET/MRI integration patterns can be assigned to tumour grades according to the WHO classification. This finding may improve tumour delineation and therapy planning for gliomas.
Autores: Domínguez, Pablo Daniel; et al.
ISSN 0003-9942  Vol. 69  Nº 12  2012  págs. 1652 - 1653
Autores: Prieto, Elena; Arbizu, Javier Ignacio; et al.
Revista: BRAIN
ISSN 0006-8950  Vol. 135  2012  págs. 2817-25
Neuronal loss in Alzheimer's disease, a better correlate of cognitive impairment than amyloid deposition, is currently gauged by the degree of regional atrophy. However, functional markers, such as GABA(A) receptor density, a marker of neuronal integrity, could be more sensitive. In post-mortem hippocampus, GABA(A) messenger RNA expression is reduced even in mild cognitive impairment. We measured whole-brain GABA(A) binding potential in vivo using [(11)C]-flumazenil positron emission tomography and compared GABA(A) binding with metabolic and volumetric measurements. For this purpose, we studied 12 subjects, six patients with early Alzheimer's disease and six healthy controls, with [(11)C]-flumazenil and [(18)F]-fluorodeoxyglucose positron emission tomography, as well as with high-resolution magnetic resonance imaging. Data were evaluated with both voxel-based parametric methods and volume of interest methods. We found that in early Alzheimer's disease, with voxel-based analysis, [(11)C]-flumazenil binding was decreased in infero-medial temporal cortex, retrosplenial cortex and posterior perisylvian regions. Inter-group differences reached corrected significance when using an arterial input function. Metabolism measured with positron emission tomography and volumetric measurements obtained with magnetic resonance imaging showed changes in regions affected in early Alzheimer's disease, but, unlike with [(11)C]-flumazenil binding and probably due to sample size, the voxel-based findings failed to reach corrected significance in any region of the brain. With volume of interest analysis, hippocampi and posterior cingulate gyrus showed decreased [(11)C]-flumazenil binding. In addition, [(11)C]-flumazenil hippocampal binding correlated with memory performance. Remarkably, [(11)C]-flumazenil binding was decreased precisely in the regions showing the greatest degree of neuronal loss in post-mortem studies of early Alzheimer's disease. From these data, we conclude that [(11)C]-flumazenil binding could be a useful marker of neuronal loss in early Alzheimer's disease
Autores: Prieto, Elena; et al.
ISSN 0212-6982  Vol. 30  Nº 2  2011  págs. 88 - 93
(18)F-FDOPA is an amino acid analogue used to evaluate presynaptic dopaminergic activity, which has aroused great interest in neuro-oncology. We have evaluated five (18)F-FDOPA PET studies of patients referred for study of parkinsonian syndrome. Two subjects had previously treated high-grade brain tumors, one nonspecific brain injury, and 2 subjects presented unexpected tumoral lesions. For all lesions SUVmax, time to SUVmax and tumor-to-normal grey matter SUVmax rate (T/N) were calculated, and 90 minutes (18)F-FDOPA kinetics were analyzed. Tumor lesions corresponded to three malignant neurocytomas, one meningioma, one pineocytoma and one intrasinusal hemangioma. Both malignant and benign tumors exhibited high uptake of (18)F-FDOPA well above the normal cortex. However, the analysis of the curve uptake displayed characteristic patterns that facilitate the characterization of tumor lesions. A dual phase maximum uptake was observed, with an early 10 minutes uptake in malignant lesions, and a late 60 to 90 minutes uptake in benign or low grade lesions.
Autores: Luquin, María Rosario Isabel; et al.
Revista: Brain Research
ISSN 0006-8993  Vol. 1375  2011  págs. 120 -127
Striatal carotid body cell aggregates (CBCA) grafts improve parkinsonism in animals and patients with Parkinson's disease. As CB cells contain trophic factors, we investigated the long-term effect of striatal CBCA grafts on nigrostriatal dopaminergic cells in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys receiving unilateral (UL-grafted group, n=4) or bilateral (BL-grafted group, n=3) CBCA autotransplant. Two MPTP monkeys were sham-operated receiving only Tyrode. For histological analysis, we also included 3 MPTP-untreated and 3 intact animals. Brain [18]F-luorodopa ((18)F-DOPA)-positron emission tomography (PET) scans were performed to assess dopaminergic function in vivo at baseline, 6 and 12months after surgery. The number of nigral dopaminergic cells was assessed in UL-grafted animals, and the number of dopaminergic cells expressing glial cell line-derived neurotrophic factor (GDNF) in all groups. After 1 year, animals showed a significant recovery of the parkinsonism (San Sebastian et al., 2007) and PET studies revealed a larger striatal (18)F-DOPA uptake in the CBCA-grafted striatum compared to that receiving Tyrode. No differences were found in the number of surviving dopaminergic cells when comparing both subtantia nigra of UL-grafted animals. However, both UL- and BL-grafted animals showed a bilaterally increased number of TH-GDNF immunoreactive nigral neurons compared to intact and MPTP-untreated monkeys, indicating that in addition to the proven long-term motor benefit, CBCA autograft might exert a neuroprotective effect on the surviving dopaminergic cells.
Autores: Prieto, Elena; Marti-Climent, JM; et al.
ISSN 0161-5505  Vol. 52  Nº 6  2011  págs. 865-72
Compared with standard (18)F-FDG PET studies, quantitative dual-time-point (18)F-FDG PET can improve sensitivity for the identification and volume delineation of high-grade brain tumors.
Autores: Arbizu, Javier Ignacio; Domínguez, Pablo Daniel; Diez Valle, Ricardo; et al.
ISSN 0212-6982  Vol. 30  Nº 1  2011  págs. 47-65
Autores: Iñarrairaegui, Mercedes; Rodríguez-Fraile, M; et al.
Revista: International Journal of Radiation Oncology, Biology, Physics
ISSN 0360-3016  Vol. 77  Nº 5  2010  págs. 1441 - 1448
Autores: Prieto, Elena; Marti-Climent, JM; Arbizu, Javier Ignacio; et al.
Revista: Computers in Biology and Medicine
ISSN 0010-4825  Vol. 40  Nº 1  2010  págs. 75 - 80
Autores: Marti-Climent, JM; Prieto, Elena; López Lafuente, J; et al.
ISSN 0212-6982  Vol. 29  Nº 4  2010  págs. 189-210
Autores: Juri, Carlos Andrés; Collantes M; Peñuelas, Iván; et al.
Revista: Neurobiology of Disease
ISSN 0969-9961  Vol. 38  Nº 3  2010  págs. 456 - 463
Autores: Prieto, Elena; Arbizu, Javier Ignacio; et al.
Revista: STROKE
ISSN 0039-2499  Vol. 41  Nº 12  2010  págs. 2889-93
The anatomy of metabolic abnormalities in vascular disease with dementia suggests that, at least in some cases, dementia with vascular disease may be independent of AD. The metabolic abnormality involves the thalamus, caudate, and frontal lobe, a pattern concordant with the neuropsychological findings of impaired executive function characteristic of vascular dementia.
Autores: Bilbao, José Ignacio; et al.
Revista: Cardiovascular and Interventional Radiology
ISSN 0174-1551  Vol. 33  Nº 3  2010  págs. 523 - 531
Autores: Iñarrairaegui, Mercedes; Thurston Kenneth, G; Bilbao, José Ignacio; et al.
Revista: Journal of vascular and interventional radiology (Print)
ISSN 1051-0443  Vol. 21  Nº 8  2010  págs. 1205 - 1212
Autores: Arbizu, Javier Ignacio; Rodríguez-Fraile, M; Marti-Climent, JM; et al.
Libro:  Liver radioembolization with 90Y microspheres
2014  págs. 63-75
Autores: Arbizu, Javier Ignacio; Bilbao, José Ignacio; et al.
Libro:  Therapeutic Nuclear Medicine
2014  págs. 361-377
Autores: Arbizu, Javier Ignacio; Gállego, Jaime; et al.
Libro:  Medicina Nuclear en la práctica clínica
2012  págs. 355-378