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1.
Int J Neural Syst ; 33(1): 2350001, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36599664

RESUMO

Deep learning for automated interictal epileptiform discharge (IED) detection has been topical with many published papers in recent years. All existing works viewed EEG signals as time-series and developed specific models for IED classification; however, general time-series classification (TSC) methods were not considered. Moreover, none of these methods were evaluated on any public datasets, making direct comparisons challenging. This paper explored two state-of-the-art convolutional-based TSC algorithms, InceptionTime and Minirocket, on IED detection. We fine-tuned and cross-evaluated them on a public (Temple University Events - TUEV) and two private datasets and provided ready metrics for benchmarking future work. We observed that the optimal parameters correlated with the clinical duration of an IED and achieved the best area under precision-recall curve (AUPRC) of 0.98 and F1 of 0.80 on the private datasets, respectively. The AUPRC and F1 on the TUEV dataset were 0.99 and 0.97, respectively. While algorithms trained on the private sets maintained their performance when tested on the TUEV data, those trained on TUEV could not generalize well to the private data. These results emerge from differences in the class distributions across datasets and indicate a need for public datasets with a better diversity of IED waveforms, background activities and artifacts to facilitate standardization and benchmarking of algorithms.


Assuntos
Epilepsia , Humanos , Epilepsia/diagnóstico , Couro Cabeludo , Eletroencefalografia/métodos , Algoritmos
2.
AJNR Am J Neuroradiol ; 42(10): 1847-1852, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34503944

RESUMO

BACKGROUND AND PURPOSE: Accurate differentiation of paragangliomas and schwannomas in the jugular foramen has important clinical implications because treatment strategies may vary but differentiation is not always straightforward with conventional imaging. Our aim was to evaluate the accuracy of both qualitative and quantitative metrics derived from dynamic contrast-enhanced MR imaging using golden-angle radial sparse parallel MR imaging to differentiate paragangliomas and schwannomas in the jugular foramen. MATERIALS AND METHODS: A retrospective study of imaging data was performed on patients (n = 30) undergoing MR imaging for jugular foramen masses with the golden-angle radial sparse parallel MR imaging technique. Imaging data were postprocessed to obtain time-intensity curves and quantitative parameters. Data were normalized to the dural venous sinus for relevant parameters and analyzed for statistical significance using a Student t test. A univariate logistic model was created with a binary output, paraganglioma or schwannoma, using a wash-in rate as a variable. Additionally, lesions were clustered on the basis of the wash-in rate and washout rate using a 3-nearest neighbors method. RESULTS: There were 22 paragangliomas and 8 schwannomas. All paragangliomas demonstrated a type 3 time-intensity curve, and all schwannomas demonstrated a type 1 time-intensity curve. There was a statistically significant difference between paragangliomas and schwannomas when comparing their values for area under the curve, peak enhancement, wash-in rate, and washout rate. A univariate logistic model with a binary output (paraganglioma or schwannoma) using wash-in rate as a variable was able to correctly predict all observed lesions (P < .001). All 30 lesions were classified correctly by using a 3-nearest neighbors method. CONCLUSIONS: Paragangliomas at the jugular foramen can be reliably differentiated from schwannomas using golden-angle radial sparse parallel MR imaging-dynamic contrast-enhanced imaging when imaging characteristics cannot suffice.


Assuntos
Forâmen Jugular , Neurilemoma , Paraganglioma , Meios de Contraste , Humanos , Imageamento por Ressonância Magnética , Neurilemoma/diagnóstico por imagem , Paraganglioma/diagnóstico por imagem , Estudos Retrospectivos
3.
AJNR Am J Neuroradiol ; 42(1): 88-93, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33184071

RESUMO

BACKGROUND AND PURPOSE: Previous hippocampal proton MR spectroscopic imaging distinguished patients with schizophrenia from controls by elevated Cr levels and significantly more variable NAA and Cho concentrations. This goal of this study was to ascertain whether this metabolic variability is associated with clinical features of the syndrome, possibly reflecting heterogeneous hippocampal pathologies and perhaps variability in its "positive" (psychotic) and "negative" (social and emotional deficits) symptoms. MATERIALS AND METHODS: In a sample of 15 patients with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, we examined the association of NAA and Cho levels with research diagnostic interviews and clinical symptom ratings of the patients. Metabolite concentrations were previously obtained with 3D proton MR spectroscopic imaging at 3T, a technique that facilitates complete coverage of this small, irregularly shaped, bilateral, temporal lobe structure. RESULTS: The patient cohort comprised 8 men and 7 women (mean age, 39.1 [SD, 10.8] years, with a mean disease duration of 17.2 [SD, 10.8] years. Despite the relatively modest cohort size, we found the following: 1) Elevated Cho levels predict the positive (psychotic, r = 0.590, P = .021) and manic (r = 0.686, P = .005) symptom severity; and 2) lower NAA levels trend toward negative symptoms (r = 0.484, P = .08). No clinical symptoms were associated with Cr level or hippocampal volume (all, P ≥ .055). CONCLUSIONS: These preliminary findings suggest that NAA and Cho variations reflect different pathophysiologic processes, consistent with microgliosis/astrogliosis and/or lower vitality (reduced NAA) and demyelination (elevated Cho). In particular, the active state-related symptoms, including psychosis and mania, were associated with demyelination. Consequently, their deviations from the means of healthy controls may be a marker that may benefit precision medicine in selection and monitoring of schizophrenia treatment.


Assuntos
Hipocampo/metabolismo , Esquizofrenia/complicações , Esquizofrenia/metabolismo , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Colina/metabolismo , Feminino , Hipocampo/patologia , Humanos , Masculino , Mania/etiologia , Pessoa de Meia-Idade , Espectroscopia de Prótons por Ressonância Magnética/métodos , Transtornos Psicóticos/etiologia
4.
AJNR Am J Neuroradiol ; 38(6): 1117-1121, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28495945

RESUMO

BACKGROUND AND PURPOSE: Preoperative localization of the pituitary gland with imaging in patients with macroadenomas has been inadequately explored. The pituitary gland enhancing more avidly than a macroadenoma has been described in the literature. Taking advantage of this differential enhancement pattern, our aim was to evaluate the role of high-resolution dynamic MR imaging with golden-angle radial sparse parallel reconstruction in localizing the pituitary gland in patients undergoing trans-sphenoidal resection of a macroadenoma. MATERIALS AND METHODS: A retrospective study was performed in 17 patients who underwent trans-sphenoidal surgery for pituitary macroadenoma. Radial volumetric interpolated brain examination sequences with golden-angle radial sparse parallel technique were obtained. Using an ROI-based method to obtain signal-time curves and permeability measures, 3 separate readers identified the normal pituitary gland distinct from the macroadenoma. The readers' localizations were then compared with the intraoperative location of the gland. Statistical analyses were performed to assess the interobserver agreement and correlation with operative findings. RESULTS: The normal pituitary gland was found to have steeper enhancement-time curves as well as higher peak enhancement values compared with the macroadenoma (P < .001). Interobserver agreement was almost perfect in all 3 planes (κ = 0.89). In the 14 cases in which the gland was clearly identified intraoperatively, the correlation between the readers' localization and the true location derived from surgery was also nearly perfect (κ = 0.95). CONCLUSIONS: This study confirms our ability to consistently and accurately identify the normal pituitary gland in patients with macroadenomas with the golden-angle radial sparse parallel technique with quantitative permeability measurements and enhancement-time curves.


Assuntos
Adenoma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Hipófise/diagnóstico por imagem , Neoplasias Hipofisárias/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
AJNR Am J Neuroradiol ; 37(12): 2273-2279, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27444940

RESUMO

BACKGROUND AND PURPOSE: Schizophrenia is well-known to be associated with hippocampal structural abnormalities. We used 1H-MR spectroscopy to test the hypothesis that these abnormalities are accompanied by NAA deficits, reflecting neuronal dysfunction, in patients compared with healthy controls. MATERIALS AND METHODS: Nineteen patients with schizophrenia (11 men; mean age, 40.6 ± 10.1 years; mean disease duration, 19.5 ± 10.5 years) and 11 matched healthy controls (5 men; mean age, 33.7 ± 10.1 years) underwent MR imaging and multivoxel point-resolved spectroscopy (TE/TR, 35/1400 ms) 1H-MRS at 3T to obtain their hippocampal GM absolute NAA, Cr, Cho, and mIns concentrations. Unequal variance t tests and ANCOVA were used to compare patients with controls. Bilateral volumes from manually outlined hippocampal masks were compared by using unequal variance t tests. RESULTS: Patients' average hippocampal GM Cr concentrations were 19% higher than that of controls, 8.7 ± 2.2 versus 7.4 ± 1.2 mmol/L (P < .05); showing no differences, concentrations in NAA were 8.8 ± 1.6 versus 8.7 ± 1.2 mmol/L; in Cho, 2.3 ± 0.7 versus 2.1 ± 0.3 mmol/L; and in mIns, 6.1 ± 1.5 versus 5.2 ± 0.9 (all P > .1). There was a positive correlation between mIns and Cr in patients (r = 0.57, P = .05) but not in controls. The mean bilateral hippocampal volume was ∼10% lower in patients: 7.5 ± 0.9 versus 8.4 ± 0.7 cm3 (P < .05). CONCLUSIONS: These findings suggest that the hippocampal volume deficit in schizophrenia is not due to net loss of neurons, in agreement with histopathology studies but not with prior 1H-MR spectroscopy reports. Elevated Cr is consistent with hippocampal hypermetabolism, and its correlation with mIns may also suggest an inflammatory process affecting some cases; these findings may suggest treatment targets and markers to monitor them.


Assuntos
Hipocampo/diagnóstico por imagem , Imageamento Tridimensional/métodos , Neuroimagem/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Esquizofrenia/metabolismo , Adulto , Ácido Aspártico/metabolismo , Colina/metabolismo , Creatina/metabolismo , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/patologia
6.
J Endocrinol Invest ; 39(7): 799-803, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26797707

RESUMO

PURPOSE: To evaluate whether high LH/FSH ratio has a clinical impact on patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization (IVF) with GnRH-agonist/antagonist protocols or in vitro maturation (IVM) treatments. METHODS: We retrospectively reviewed all PCOS patients with day 3 LH/FSH ratio ≥1.5 who underwent IVF or IVM. The main outcomes measures were embryo quality and pregnancy rate. RESULTS: A total of 75 cycles were included. Among these, 44 patients underwent long agonist protocol, 16 antagonist protocol and 15 IVM. Age, basal LH and FSH levels, as well as duration of infertility were comparable for all groups. The LH level on the day of hCG administration was significantly lower in the antagonist group (0.9 IU/ml) compared to the long agonist group (1.4 IU/ml, p = 0.01). There was no difference in pregnancy rates among the groups: 27.2 % in the long agonist group, 37.5 % in the antagonist group and 26.6 % among the IVM patients. CONCLUSIONS: High LH/FSH ratio had no adverse effect on pregnancy rates in all three treatment modes.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/sangue , Antagonistas de Hormônios/uso terapêutico , Técnicas de Maturação in Vitro de Oócitos , Infertilidade Feminina/prevenção & controle , Hormônio Luteinizante/sangue , Síndrome do Ovário Policístico/complicações , Adulto , Biomarcadores/sangue , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Infertilidade Feminina/etiologia , Indução da Ovulação , Síndrome do Ovário Policístico/sangue , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Pamoato de Triptorrelina/análogos & derivados , Pamoato de Triptorrelina/uso terapêutico , Ultrassonografia
7.
AJNR Am J Neuroradiol ; 36(11): 2055-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26294651

RESUMO

BACKGROUND AND PURPOSE: Although NAA is often used as a marker of neuronal health and integrity in neurologic disorders, its normal response to physiologic challenge is not well-established and its changes are almost always attributed exclusively to brain pathology. The purpose of this study was to test the hypothesis that the neuronal cell marker NAA, often used to assess neuronal health and integrity in neurologic disorders, is not confounded by (possibly transient) physiologic changes. Therefore, its decline, when observed by using (1)H-MR spectroscopy, can almost always be attributed exclusively to brain pathology. MATERIALS AND METHODS: Twelve healthy young male adults underwent a transient hypercapnia challenge (breathing 5% CO2 air mixture), a potent vasodilator known to cause a substantial increase in CBF and venous oxygenation. We evaluated their whole-brain NAA by using nonlocalizing proton MR spectroscopy, venous oxygenation with T2-relaxation under spin-tagging MR imaging, CBF with pseudocontinuous arterial spin-labeling, and the cerebral metabolic rate of oxygen, during normocapnia (breathing room air) and hypercapnia. RESULTS: There was insignificant whole-brain NAA change (P = .88) from normocapnia to hypercapnia and back to normocapnia in this cohort, as opposed to highly significant increases: 28.0 ± 10.3% in venous oxygenation and 49.7 ± 16.6% in global CBF (P < 10(-4)); and a 6.4 ± 10.9% decrease in the global cerebral metabolic rate of oxygen (P = .04). CONCLUSIONS: Stable whole-brain NAA during normocapnia and hypercapnia, despite significant global CBF and cerebral metabolic rate of oxygen changes, supports the hypothesis that global NAA changes are insensitive to transient physiology. Therefore, when observed, they most likely reflect underlying pathology resulting from neuronal cell integrity/viability changes, instead of a response to physiologic changes.


Assuntos
Ácido Aspártico/análogos & derivados , Química Encefálica/fisiologia , Encéfalo/metabolismo , Hipercapnia/metabolismo , Adulto , Ácido Aspártico/análise , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Adulto Jovem
8.
AJNR Am J Neuroradiol ; 36(8): 1444-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25953760

RESUMO

BACKGROUND AND PURPOSE: The pituitary gland is located outside of the blood-brain barrier. Dynamic T1 weighted contrast enhanced sequence is considered to be the gold standard to evaluate this region. However, it does not allow assessment of intrinsic permeability properties of the gland. Our aim was to demonstrate the utility of radial volumetric interpolated brain examination with the golden-angle radial sparse parallel technique to evaluate permeability characteristics of the individual components (anterior and posterior gland and the median eminence) of the pituitary gland and areas of differential enhancement and to optimize the study acquisition time. MATERIALS AND METHODS: A retrospective study was performed in 52 patients (group 1, 25 patients with normal pituitary glands; and group 2, 27 patients with a known diagnosis of microadenoma). Radial volumetric interpolated brain examination sequences with golden-angle radial sparse parallel technique were evaluated with an ROI-based method to obtain signal-time curves and permeability measures of individual normal structures within the pituitary gland and areas of differential enhancement. Statistical analyses were performed to assess differences in the permeability parameters of these individual regions and optimize the study acquisition time. RESULTS: Signal-time curves from the posterior pituitary gland and median eminence demonstrated a faster wash-in and time of maximum enhancement with a lower peak of enhancement compared with the anterior pituitary gland (P < .005). Time-optimization analysis demonstrated that 120 seconds is ideal for dynamic pituitary gland evaluation. In the absence of a clinical history, differences in the signal-time curves allow easy distinction between a simple cyst and a microadenoma. CONCLUSIONS: This retrospective study confirms the ability of the golden-angle radial sparse parallel technique to evaluate the permeability characteristics of the pituitary gland and establishes 120 seconds as the ideal acquisition time for dynamic pituitary gland imaging.


Assuntos
Adenoma/patologia , Permeabilidade Capilar , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Hipófise/patologia , Neoplasias Hipofisárias/patologia , Adenoma/fisiopatologia , Adulto , Compressão de Dados/métodos , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Hipófise/irrigação sanguínea , Neoplasias Hipofisárias/fisiopatologia , Estudos Retrospectivos
9.
HIV Med ; 16(6): 381-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25689120

RESUMO

OBJECTIVES: As ∼40% of HIV-infected individuals experience neurocognitive decline, we investigated whether proton magnetic resonance spectroscopic imaging ((1) H-MRSI) detects early metabolic abnormalities in the cerebral cortex of a simian immunodeficiency virus (SIV)-infected rhesus monkey model of neuroAIDS. METHODS: The brains of five rhesus monkeys before and 4 or 6 weeks after SIV infection (with CD8(+) T-cell depletion) were assessed with T2 -weighted quantitative magnetic resonance imaging (MRI) and 16×16×4 multivoxel (1) H-MRSI (echo time/repetition time = 33/1440 ms). Grey matter and white matter masks were segmented from the animal MRIs and used to produce cortical masks co-registered to (1) H-MRSI data to yield cortical metabolite concentrations of the glial markers myo-inositol (mI), creatine (Cr) and choline (Cho), and of the neuronal marker N-acetylaspartate (NAA). The cortex volume within the large, 28 cm(3) (∼35% of total monkey brain) volume of interest was also calculated for each animal pre- and post-infection. Mean metabolite concentrations and cortex volumes were compared pre- and post-infection using paired sample t-tests. RESULTS: The mean (± standard deviation) pre-infection concentrations of the glial markers mI, Cr and Cho were 5.8 ± 0.9, 7.2 ± 0.4 and 0.9 ± 0.1 mM, respectively; these concentrations increased 28% (p ≈ 0.06), 15% and 10% (both p < 0.05), respectively, post-infection. The mean concentration of neuronal marker NAA remained unchanged (7.0 ± 0.6 mM pre-infection vs. 7.3 ± 0.8 mM post-infection; p ≈ 0.37). The mean cortex volume was also unchanged (8.1 ± 1.1 cm(3) pre-infection vs. 8.3 ± 0.5 cm(3) post-infection; p ≈ 0.76). CONCLUSIONS: These results support the hypothesis that early cortical glial activation occurs after SIV infection prior to the onset of neurodegeneration. This suggests HIV therapeutic interventions should potentially target early glial activation in the cerebral cortex.


Assuntos
Córtex Cerebral/patologia , Síndrome de Imunodeficiência Adquirida dos Símios , Animais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Biomarcadores/metabolismo , Doenças do Sistema Nervoso Central/etiologia , Córtex Cerebral/metabolismo , Colina/metabolismo , Creatina/metabolismo , Modelos Animais de Doenças , Feminino , Macaca mulatta , Masculino , Espectroscopia de Prótons por Ressonância Magnética , Síndrome de Imunodeficiência Adquirida dos Símios/complicações , Síndrome de Imunodeficiência Adquirida dos Símios/patologia , Vírus da Imunodeficiência Símia
10.
Acta Neurol Scand ; 131(1): 58-62, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25273688

RESUMO

OBJECTIVE: Up to one-third of individuals diagnosed as having epilepsy continue to have seizures despite appropriate anti-epileptic drug treatment. These patients are often referred for presurgical evaluation, and many are rejected from focal resective surgery due to medical reasons or, alternatively, they choose not to undergo it. We compared the outcomes and characteristics of the non-operated patients who continued on medical therapy alone with those who underwent vagus nerve stimulator (VNS) implantation in addition to medical therapy. METHODS: The medical records of consecutive adult patients referred for presurgical evaluation for suitability for epilepsy surgery in the Tel-Aviv Sourasky Medical Center between 2007 and 2011 and were rejected from or decided against surgery were reviewed. Updated information on seizure frequency was supplemented by telephone interviews between April and July, 2013. RESULTS: Fifty-two patients who continued solely on medical therapy and 35 patients who additionally underwent VNS implantation were included in the study. Forty-seven of the former and 33 of the latter agreed to be interviewed. There was a significant improvement in the seizure frequency between the time of the presurgical evaluation and the time of the interview in both groups. Eight medically treated patients (17%) and 2 patients who also underwent VNS implantation (6%) reported being seizure-free during the preceding 3 months. CONCLUSIONS: A considerable minority of patients with refractory epilepsy who were rejected or chose not to undergo epilepsy surgery may improve over time and even become seizure-free following adjustment of anti-epileptic drugs with or without concomitant VNS.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/terapia , Convulsões/prevenção & controle , Estimulação do Nervo Vago , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento , Adulto Jovem
11.
Neurology ; 78(18): 1383-9, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22517095

RESUMO

OBJECTIVES: To test the hypotheses that 1) patients with relapsing-remitting multiple sclerosis (RR-MS) exhibit a quantifiable decline in their whole-brain concentration of the neural marker N-acetyl-L-aspartate (WBNAA), that is 2) more sensitive than clinical changes and 3) may provide a practical outcome measure for proof-of-concept and larger phase III clinical trials. METHODS: Nineteen patients (5 men and 14 women) with clinically definite RR-MS, who were 33 ± 5 years old (mean ± SD), had a disease duration of 47 ± 28 months, and had a median Expanded Disability Status Scale (EDSS) score of 1.0 (range 0-5.5), underwent MRI and proton magnetic resonance spectroscopy ((1)H-MRS) semiannually for 2 years (5 time points). Eight matched control subjects underwent the protocol annually (3 time points). Their global N-acetyl-L-aspartate (1)H-MRS signal was converted into absolute amounts by phantom replacement and into WBNAA by dividing with the brain parenchymal volume, V(B), from MRI segmentation. RESULTS: The baseline WBNAA of the patients (10.5 ± 1.7 mM) was significantly lower than that of the controls (12.3 ± 1.3 mM; p < 0.002) and declined significantly (5%/year, p < 0.002) vs that for the controls who did not show a decline (0.4%/year, p > 0.7). Likewise, V(B) values of the patients also declined significantly (0.5%/year, p < 0.0001), whereas those of the controls did not (0.2%/year, p = 0.08). The mean EDSS score of the patients increased insignificantly from 1.0 to 1.5 (range 0-6.0) and did not correlate with V(B) or WBNAA. CONCLUSIONS: WBNAA of patients with RR-MS declined significantly at both the group and individual levels over a 2-year time period common in clinical trials. Because of the small sample sizes required to establish power, WBNAA can be incorporated into future studies.


Assuntos
Ácido Aspártico/análogos & derivados , Biomarcadores/sangue , Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Adulto , Ácido Aspártico/metabolismo , Encéfalo/patologia , Estudos de Coortes , Avaliação da Deficiência , Feminino , Humanos , Análise dos Mínimos Quadrados , Estudos Longitudinais , Masculino , Neurônios/patologia , Tamanho do Órgão/fisiologia , Valor Preditivo dos Testes , Prognóstico , Estatística como Assunto
12.
Andrologia ; 44(2): 73-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21714800

RESUMO

The aim of this study was to find discriminatory parameters, based on sperm characteristics on the day of ovum pickup, that can help guide the decision to perform either intracytoplasmic sperm injection (ICSI) or in vitro fertilisation (IVF). We evaluated 112 cycles fertilised with both regular and ICSI insemination during the same cycle. A total of 112 cycles were analysed. In 62 cycles, fertilisation was obtained with both ICSI and IVF, and in 50 cycles, fertilisation was obtained by ICSI alone. The sperm samples were re-evaluated after the preparation process. The mean initial total motile sperm count (TMSC) was 66.3 × 10(6) ± 47.5 in the group that underwent both methods and 23.1 × 10(6) ± 20.4 in the ICSI only group (P < 0.05). After sperm preparation, the mean post-wash TMSC was 4.4 × 10(6) ± 3.4 and 1.06 × 10(6) ± 0.9 respectively (P < 0.05). A cutoff of 1.5 × 10(6) or fewer sperm after preparation as an indicator for ICSI has a sensitivity of 80% and a specificity of 77%. Re-evaluation of TMSC can prevent unexpected fertilisation failure. Fewer than 1.5 million TMSC after wash should be considered an indication for ICSI fertilisation.


Assuntos
Análise do Sêmen , Espermatozoides/fisiologia , Técnicas de Apoio para a Decisão , Feminino , Fertilização in vitro/métodos , Humanos , Infertilidade Masculina/terapia , Masculino , Sensibilidade e Especificidade , Contagem de Espermatozoides , Injeções de Esperma Intracitoplásmicas/métodos , Motilidade dos Espermatozoides
13.
Mult Scler ; 18(1): 98-107, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21921070

RESUMO

BACKGROUND: The ability to predict the course of multiple sclerosis (MS) is highly desirable but lacking. OBJECTIVE: To test whether the MS Severity Scale (MSSS) and global neuronal viability, assessed through the quantification of the whole-brain N-acetylaspartate concentration (WBNAA), concur or complement the assessment of individual patients' disease course. METHODS: The MSSS and average WBNAA loss rate (ΔWBNAA, extrapolated based on one current measurement and the assumption that at disease onset neural sparing was similar to healthy controls, obtained with proton magnetic resonance (MR) spectroscopy and magnetic resonance imaging (MRI)) from 61 patients with MS (18 male and 43 female) with long disease duration (15 years or more) were retrospectively examined. Some 27 patients exhibited a 'benign' disease course, characterized by an Expanded Disability Status Scale score (EDSS) of 3.0 or less, and 34 were 'non-benign': EDSS score higher than 3.0. RESULTS: The two cohorts were indistinguishable in age and disease duration. Benign patients' EDSS and MSSS (2.1 ± 0.7, 1.15 ± 0.60) were significantly lower than non-benign (4.6 ± 1.0, 3.6 ± 1.2; both p < 10(-4)). Their respective average ΔWBNAA, 0.10 ± 0.16 and 0.11 ± 0.12 mM/year, however, were not significantly different (p > 0.7). While MSSS is both sensitive to (92.6%) and specific for (97.0%) benign MS, ΔWBNAA is only sensitive (92.6%) but not specific (2.9%). CONCLUSION: Since the WBNAA loss rate is similar in both phenotypes, the only difference between them is their clinical classification, characterized by MSSS and EDSS. This may indicate that 'benign' MS probably reflects fortuitous sparing of clinically eloquent brain regions and better utilization of brain plasticity.


Assuntos
Ácido Aspártico/análogos & derivados , Biomarcadores/análise , Encéfalo/metabolismo , Esclerose Múltipla/metabolismo , Índice de Gravidade de Doença , Ácido Aspártico/análise , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
AJNR Am J Neuroradiol ; 32(6): 1011-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21511862

RESUMO

BACKGROUND AND PURPOSE: Although NAA is often used as a marker of neural integrity and health in different neurologic disorders, the temporal behavior of WBNAA is not well characterized. Our goal therefore was to establish its normal variations in a cohort of healthy adults over typical clinical trial periods. MATERIALS AND METHODS: Baseline amount of brain NAA, Q(NAA), was obtained with nonlocalizing proton MR spectroscopy from 9 subjects (7 women, 2 men; 31.2 ± 5.6 years old). Q(NAA) was converted into absolute millimole amount by using phantom-replacement. The WBNAA concentration was derived by dividing Q(NAA) with the brain parenchyma volume, V(B), segmented from MR imaging. Temporal variations were determined with 4 annual scans of each participant. RESULTS: The distribution of WBNAA levels was not different among time points with respect to the mean, 12.1 ± 1.5 mmol/L (P > .6), nor was its intrasubject change (coefficient of variation = 8.6%) significant between any 2 scans (P > .5). There was a small (0.2 mL) but significant (P = .05) annual V(B) decline. CONCLUSIONS: WBNAA is stable over a 3-year period in healthy adults. It qualifies therefore as a biomarker for global neuronal loss and dysfunction in diffuse neurologic disorders that may be well worth considering as a secondary outcome measure candidate for clinical trials.


Assuntos
Ácido Aspártico/análogos & derivados , Química Encefálica , Espectroscopia de Ressonância Magnética/métodos , Adulto , Ácido Aspártico/análise , Feminino , Humanos , Estudos Longitudinais , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
15.
AJNR Am J Neuroradiol ; 32(1): 204-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20966065

RESUMO

BACKGROUND AND PURPOSE: Neuro-axonal damage is a well known sequelae of MS pathogeneses. Consequently, our aim was to test whether the ∼20% of patients with MS exhibiting a clinically benign disease course also have minimal neural dysfunction as reflected by the global concentration of their MR imaging marker NAA. MATERIALS AND METHODS: Q(NAA) was obtained with nonlocalizing whole-head (1)H-MR spectroscopy in 43 patients with benign RRMS (30 women, 13 men; mean age, 44.7 ± 7.3 years of age) with 21.0 ± 4.4 years (range, 15-35 years) of disease duration from the first symptom and an EDSS score of 1.9 (range, 0-3). Q(NAA) was by divided by the brain volume (from MR imaging segmentation) to normalize it into WBNAA. All participants gave institutional review board-approved written informed consent, and the study was HIPAA compliant. RESULTS: The patients' lesion load was 12.2 ± 7.7 cm(3). Their 8.3 ± 1.8 mmol/L WBNAA was 35% lower than that in controls (P < .001). Individual average loss rates (absolute loss compared with controls divided by disease duration) clustered around 0.22 ± 0.09 mmol/L/year (1.7%/year, assuming monotonic decline). This rate could be extrapolated from that already reported for patients with RRMS of much shorter disease duration. WBNAA did not correlate with lesion load or EDSS. CONCLUSIONS: Normal WBNAA is not characteristic of benign MS and is not an early predictor of its course. These patients, therefore, probably benefit from successful compensation and sparing of eloquent regions. Because they may ultimately have a rapid decline once their brain plasticity is exhausted, they may benefit from treatment options offered to more affected patients.


Assuntos
Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Esclerose Múltipla/metabolismo , Adolescente , Adulto , Ácido Aspártico/metabolismo , Regulação para Baixo , Feminino , Humanos , Masculino , Prótons , Distribuição Tecidual , Adulto Jovem
16.
Hum Reprod ; 25(10): 2496-500, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20729538

RESUMO

BACKGROUND: The aim of this study was to evaluate the effect of dehydroepiandrosterone (DHEA) supplementation on in vitro fertilization (IVF) data and outcomes among poor-responder patients. METHODS: A randomized, prospective, controlled study was conducted. All patients received the long-protocol IVF. Those in the study group received 75 mg of DHEA once a day before starting the next IVF cycle and during treatment. RESULTS: Thirty-three women with significantly diminished ovarian reserves were enrolled, 17 in the DHEA group and 16 in the control group. The 33 patients underwent 51 IVF cycles. The DHEA group demonstrated a non-significant improvement in estradiol levels on day of hCG (P = 0.09) and improved embryo quality during treatment (P = 0.04) between first and second cycles. Patients in the DHEA group also had a significantly higher live birth rate compared with controls (23.1% versus 4.0%; P = 0.05), respectively. Six of seven deliveries were among patients with secondary infertility (P = 0.006). CONCLUSION: Dehydroepiandrosterone supplementation can have a beneficial effect on ovarian reserves for poor-responder patients on IVF treatment. Clinicaltrials.gov: NCT01145144.


Assuntos
Desidroepiandrosterona/administração & dosagem , Fertilização in vitro/efeitos dos fármacos , Adulto , Gonadotropina Coriônica/uso terapêutico , Estradiol/sangue , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Infertilidade Feminina/tratamento farmacológico , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Resultado do Tratamento
17.
Seizure ; 19(1): 12-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19963405

RESUMO

PURPOSE: To establish whether the disability in benign epilepsy with centrotemporal spikes (BECTS) is the result of the number of seizures, the anti-epileptic therapy or is an inherent characteristic of the syndrome itself. METHODS: Thirty-six children with BECTS were tested for cognitive functions prior to commencing treatment with anti-epileptic drugs, and the findings were compared with those in 15 children with normal electroencephalograms, performed for unrelated reasons. The data in the study group were further correlated with the laterality of the epileptic focus and the number of seizures. RESULTS: Scores for verbal functioning on neuropsychological tests were significantly lower in the study group than the control group. There was no relationship between the neuropsychological scores in the patients and either lateralization of the epileptic focus or number of seizures. DISCUSSION: Children with BECTS have an impaired ability to process verbal information. The deficiency is apparently a result of the pathological electrical discharges that are part of the syndrome and are not dependent on the epileptic focus laterality, the number of seizures, or the anti-epileptic treatment.


Assuntos
Transtornos Cognitivos/etiologia , Epilepsia Rolândica/complicações , Epilepsia Rolândica/psicologia , Adolescente , Análise de Variância , Criança , Transtornos Cognitivos/diagnóstico , Compreensão/fisiologia , Eletroencefalografia/métodos , Função Executiva/fisiologia , Feminino , Humanos , Testes de Inteligência , Masculino , Memória/fisiologia , Testes Neuropsicológicos , Comportamento Verbal/fisiologia
18.
J Neurol Neurosurg Psychiatry ; 80(12): 1330-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19546105

RESUMO

OBJECTIVE: To test the hypothesis that diffuse abnormalities precede axonal damage and atrophy in the MRI normal-appearing tissue of relapsing-remitting (RR) multiple sclerosis (MS) patients, and that these processes continue during clinical remission. METHODS: Twenty-one recently diagnosed mildly disabled (mean disease duration 2.3 years, mean Expanded Disability Status Scale score of 1.4) RR MS patients and 15 healthy matched controls were scanned with MRI and proton MR spectroscopic imaging ((1)H-MRSI) at 3 T. Metabolite concentrations: N-acetylaspartate (NAA) for neuronal integrity; choline (Cho) for membrane turnover rate; creatine (Cr) and myo-inositol (mI) for glial status were obtained in a 360 cm(3) volume of interest (VOI) with 3D multivoxel (1)H-MRSI. They were converted into absolute amounts using phantom replacement and normalised into absolute concentrations by dividing by the VOI tissue volume fraction obtained from MRI segmentation. RESULTS: The patients' mean VOI tissue volume fraction, 0.92 and NAA concentration, 9.6 mM, were not different from controls' 0.94 and 9.6 mM. In contrast, the patients' mean Cr, Cho and mI levels 7.7, 1.9 and 4.1 mM were 9%, 14% and 20%, higher than the controls' 7.1, 1.6 and 3.4 mM (p = 0.0097, 0.003 and 0.0023). CONCLUSIONS: The absence of early tissue atrophy and apparent axonal dysfunction (NAA loss) in these RR MS patients suggests that both are preceded by diffuse glial proliferation (astrogliosis), as well as possible inflammation, demyelination and remyelination reflected by elevated mI, Cho and Cr, even during clinical remission and despite immunomodulatory treatment.


Assuntos
Esclerose Múltipla/patologia , Adulto , Ácido Aspártico/análogos & derivados , Química Encefálica , Colina/análise , Creatina/análise , Feminino , Humanos , Inositol/análise , Espectroscopia de Ressonância Magnética , Masculino , Neuroglia/química , Indução de Remissão , Adulto Jovem
19.
AJNR Am J Neuroradiol ; 29(8): 1441-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18556356

RESUMO

BACKGROUND AND PURPOSE: Despite the prominent peak of N-acetylaspartate (NAA) in proton MR spectroscopy ((1)H-MR spectroscopy) of the adult brain and its almost exclusive presence in neuronal cells, the total amount of NAA, regarded as their marker, is difficult to obtain due to signal contamination from the skull lipids. This article compares the performance of 2 methods that overcome this difficulty to yield the whole-brain NAA signal, important for the assessment of the total disease load in diffuse neurologic disorders. MATERIALS AND METHODS: The heads of 12 healthy volunteers, 3 women and 9 men, 31.0 +/- 7.1 years of age, were scanned at 3T by using 2 nonlocalizing (1)H-MR spectroscopy sequences: One nulls the NAA (TI = 940 ms) every second acquisition by inversion-recovery to cancel the signals of the lipids (T1 << TI) in an add-subtract scheme. The other nulls the signal of the lipids (TI = 155 ms) directly after each acquisition, requiring half as many averages for the same signal-to-noise ratio. Each sequence was repeated 3 times back-to-back on 3 occasions, and the comparison criteria were intrasubject precision (reproducibility) and total measurement duration. RESULTS: NAA nulling is nearly twice as precise in its intrinsic back-to-back (5.8% versus 8.6%) as well as longitudinal (10.6% versus 19.7%) coefficients of variation compared with lipid nulling, but at the cost of double the acquisition time. CONCLUSION: When speed is a more stringent requirement than precision, the new lipid-nulling sequence is a viable alternative. For precision in cross-sectional or longitudinal global NAA quantification, however, NAA nulling is still the approach of choice despite its x2 ( approximately 5 minutes) time penalty compared with the lipid-nulling approach.


Assuntos
Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Lipídeos/análise , Espectroscopia de Ressonância Magnética/métodos , Adulto , Ácido Aspártico/análise , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
AJNR Am J Neuroradiol ; 28(10): 1843-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17921226

RESUMO

Proton MR spectroscopy (1H-MR spectroscopy) is a quantitative MR imaging technique often used to complement the sensitivity of conventional MR imaging with specific metabolic information. A key metabolite is the amino acid derivative N-acetylaspartate (NAA), which is almost exclusive to neurons and their processes and is, therefore, an accepted marker of their health and attenuation. Unfortunately, most 1H-MR spectroscopy studies only account for small 1- to 200-cm volumes of interest (VOI), representing less than 20% of the total brain volume. These VOIs have at least 5 additional restrictions: 1) To avoid contamination from subcutaneous and bone marrow lipids, they must be placed away from the skull, thereby missing most of the cortex. 2) They must be image-guided onto MR imaging-visible pathology, subjecting them to the implicit assumption that metabolic changes occur only there. 3) They encounter misregistration errors in serial studies. 4) The time needed to accumulate sufficient signal-intensity quality is often restrictive, and 5) they incur (unknown) T1- and T2-weighting. All these issues are avoided (at the cost of specific localization) by measuring the nonlocalized average NAA concentration over the entire brain. Indeed, whole-brain NAA quantification has been applied to several diffuse neurodegenerative diseases (where specific localization is less important than the total load of the pathology), and the results are presented in this review.


Assuntos
Ácido Aspártico/análogos & derivados , Neoplasias Encefálicas/patologia , Encéfalo/metabolismo , Demência/patologia , Espectroscopia de Ressonância Magnética , Esclerose Múltipla/patologia , Ácido Aspártico/análise , Biomarcadores/análise , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Demência/metabolismo , Humanos , Espectroscopia de Ressonância Magnética/métodos , Esclerose Múltipla/metabolismo , Neurônios/metabolismo , Neurônios/patologia
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