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1.
J Nutr Health Aging ; 25(9): 1042-1045, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34725659

RESUMEN

This study aimed at evaluating the predictive ability of the Physical Resilience Instrument for Older Adults (PRIFOR) for the recovery of frailty, activity of daily living (ADL), and quality of life in older adults suffering from acute health stressors. The longitudinal study was adopted and patients aged 65 and older with Clinical Frailty Scale (CFS) scores between 4 and 6 were included. The PRIFOR was used to assess physical resilience at baseline. Katz ADL, CFS and EuroQoL 5-dimension Questionnaire (EQ5D) scores were all assessed at baseline and one month after discharge. The mean age of the 192 participants was 76.29 ± 6.53 years, and 50.5% were female. After adjusting for the baseline condition, the PRIFOR was only significantly associated with the CFS (ß=-0.183, p<0.001) at one month after discharge. Our study results provide evidence of the predictive capacity of the PRIFOR for recovery from frailty.


Asunto(s)
Fragilidad , Calidad de Vida , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Femenino , Anciano Frágil , Fragilidad/complicaciones , Evaluación Geriátrica/métodos , Humanos , Estudios Longitudinales
2.
AJNR Am J Neuroradiol ; 40(3): 478-482, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30765380

RESUMEN

BACKGROUND AND PURPOSE: Patients with carbon monoxide (CO) intoxication exhibit progressive WM changes that are not well-understood. The purpose of this study was to detect longitudinal WM changes using voxelwise diffusional kurtosis imaging in patients with CO intoxication from the acute-to-chronic stage after CO intoxication. MATERIALS AND METHODS: Twenty-four patients with CO intoxication and 21 age- and sex-matched healthy controls were enrolled in this study. Diffusional kurtosis imaging was performed on all subjects and was conducted repeatedly in patients at 1 week and 1, 3, and 9 months after CO intoxication. Voxelwise diffusional kurtosis imaging analysis was performed to detect global WM changes in the patients with and without WM lesions. Receiver operating characteristic analysis was performed to compare the performance of diffusional indices in differentiating patients with delayed neuropsychiatric sequelae from patients without them. RESULTS: In voxelwise analysis, progressive WM changes were detected in patients with WM lesions. In the acute phase, WM injuries were found mainly in the dopaminergic pathways at 1 week, whereas in the chronic stage, WM injuries extended toward subcortical areas from 1 to 9 months. However, no significant WM change was noted in patients without WM lesions during the 9 months after CO intoxication. Moreover, receiver operating characteristic analysis demonstrated that axial kurtosis and mean kurtosis values had better performance than other diffusional indices in differentiating patients with delayed neuropsychiatric sequelae from patients without them at 1 week after CO intoxication. CONCLUSIONS: Voxelwise diffusional kurtosis imaging analysis was helpful to longitudinally investigate WM changes and predict the prognosis of patients after CO intoxication.


Asunto(s)
Encéfalo/diagnóstico por imagen , Intoxicación por Monóxido de Carbono/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Neuroimagen/métodos , Sustancia Blanca/diagnóstico por imagen , Adulto , Encéfalo/patología , Intoxicación por Monóxido de Carbono/patología , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Sustancia Blanca/patología
3.
AJNR Am J Neuroradiol ; 33(5): 910-4, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22282449

RESUMEN

BACKGROUND AND PURPOSE: SWI is a high-resolution 3D, fully velocity-compensated gradient-echo sequence that uses both magnitude and phase data. The purpose of this study was to investigate the phase behavior of the capsule of pyogenic brain abscesses with noncontrast SWI. MATERIALS AND METHODS: Fourteen patients with pyogenic brain abscesses were studied at 1.5T. In all of the patients, SWI images were obtained and reviewed in addition to conventional MR images. Phase values within the abscess capsule were measured and compared with those from the abscess cavities and contralateral normal white matter using 1-way repeated measures ANOVA with post hoc Bonferroni analysis. RESULTS: SWI phase images showed mild hypointesity in 6 patients, isointensity in 3 patients, and mixed iso- to mild hypointensity in 5 patients. The means of phase in the cavity, rim of abscesses, and contralateral normal white matter were -7.552 × 10(-3) ± 0.024, -0.105 ± 0.080, and +0.029 ± 0.011 radians, respectively. Post hoc comparisons showed significant differences between any pair of the 3 regions (abscess cavity, rim capsule, and normal white matter) in SWI (all Ps < .005). CONCLUSIONS: SWI phase imaging shows evidence of paramagnetic substances in agreement with the presence of free radicals from phagocytosis. SWI may provide additional information valuable in the characterization of pyogenic brain abscesses.


Asunto(s)
Algoritmos , Absceso Encefálico/patología , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
7.
AJNR Am J Neuroradiol ; 29(8): 1511-8, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18499784

RESUMEN

BACKGROUND AND PURPOSE: Abscesses caused by aerobic bacteria (aerobic abscesses) can simulate intracranial glioblastomas multiforme (GBMs) in MR imaging appearance and single voxel (SV) proton MR spectroscopy of the central cavity. The purpose of our study was to determine whether MR spectroscopic imaging (SI) can be used to differentiate aerobic abscesses from GBMs. Our hypothesis was that metabolite levels of choline (Cho) are decreased in the ring-enhancing portion of abscesses compared with GBMs. MATERIALS AND METHODS: Fifteen patients with aerobic abscesses were studied on a 1.5T MR scanner using an SV method and an SI method. Proton MR spectra of 15 GBMs with similar conventional MR imaging appearances were used for comparison. The resonance peaks in the cavity, including lactate, cytosolic amino acids, acetate, succinate, and lipids, were analyzed by both SV MR spectroscopy and MRSI. In the contrast-enhancing rim of each lesion, peak areas of N-acetylaspartate (NAA), choline (Cho), lipid and lactate (LL), and creatine (Cr) were measured by MRSI. The peak areas of NAA-n, Cho-n, and Cr-n in the corresponding contralateral normal-appearing (-n) brain were also measured. Maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios in abscesses and GBMs were compared using the Wilcoxon rank sum test. After receiver operating characteristic curve analysis, diagnostic accuracy was compared. RESULTS: Cytosolic amino acid peaks were found in the cavity in 7 of 15 patients with aerobic abscesses. Means and SDs of maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios were 3.38 +/- 1.09, 3.88 +/- 2.13, 2.72 +/- 1.45, 1.98 +/- 0.53, 0.53 +/- 0.16, and 0.44 +/- 0.09, respectively, in the GBMs, and 1.77 +/- 0.49, 1.48 +/- 0.51, 2.11 +/- 0.67, 0.81 +/- 0.21, 0.48 +/- 0.2, and 0.5 +/- 0.15, respectively, in the abscesses. Significant differences were found in the maximum Cho/Cr (P = .001), Cho/NAA (P = .006), and Cho/Cho-n ratios (P < .001) between abscesses and GBMs. Diagnostic accuracy was higher by Cho/Cho-n ratio than Cho/Cr and Cho/NAA ratios (93.3% versus 86.7% and 76.7%). CONCLUSION: Metabolite ratios and maximum Cho/Cho-n, Cho/Cr, and Cho/NAA ratios of the contrast-enhancing rim were significantly different and useful in differentiating aerobic abscesses from GBMs by MRSI.


Asunto(s)
Absceso Encefálico/diagnóstico , Glioblastoma/diagnóstico , Infecciones por Bacterias Grampositivas/diagnóstico , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Bacterias Aerobias , Neoplasias Encefálicas , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Necrosis , Protones , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
J Med Ethics ; 33(5): 261-5, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17470500

RESUMEN

OBJECTIVES: To study the attitudes of both medical and non-medical students towards the do-not-resuscitate (DNR) decision in a university in Hong Kong, and the factors affecting their attitudes. METHODS: A questionnaire-based survey conducted in the campus of a university in Hong Kong. Preferences and priorities of participants on cardiopulmonary resuscitation in various situations and case scenarios, experience of death and dying, prior knowledge of DNR and basic demographic data were evaluated. RESULTS: A total of 766 students participated in the study. There were statistically significant differences in their DNR decisions in various situations between medical and non-medical students, clinical and preclinical students, and between students who had previously experienced death and dying and those who had not. A prior knowledge of DNR significantly affected DNR decision, although 66.4% of non-medical students and 18.7% of medical students had never heard of DNR. 74% of participants from both medical and non-medical fields considered the patient's own wish as the most important factor that the healthcare team should consider when making DNR decisions. Family wishes might not be decisive on the choice of DNR. CONCLUSIONS: Students in medical and non-medical fields held different views on DNR. A majority of participants considered the patient's own wish as most important in DNR decisions. Family wishes were considered less important than the patient's own wishes.


Asunto(s)
Actitud del Personal de Salud , Toma de Decisiones , Órdenes de Resucitación/ética , Valores Sociales , Estudiantes de Medicina/psicología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Actitud Frente a la Muerte , Ética Profesional , Femenino , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Defensa del Paciente , Guías de Práctica Clínica como Asunto , Órdenes de Resucitación/psicología , Encuestas y Cuestionarios
10.
AJNR Am J Neuroradiol ; 28(1): 68-71, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17213426

RESUMEN

BACKGROUND AND PURPOSE: The dynamics of brain-water content associated with hemodialysis in patients with severe azotemia remains obscure. To investigate whether either interstitial or cytotoxic edema is responsible for dialysis disequilibrium syndrome (DDS), we used diffusion-weighted MR imaging (DWI) to measure the apparent diffusion coefficient (ADC), which is sensitive for detecting tissue water dynamics. METHODS: Eight consecutive patients with end stage renal disease (ESRD) and blood urea nitrogen level of more than 100 mg/dL (160.9 +/- 53.1 mg/dL) were recruited. Conventional MR images, DWI, and clinical manifestations were obtained before and after the 1st hemodialysis. The ADC values were determined for regions of normal-appearing gray and white matter and for regions of hyperintensity of white matter on T2-weighted MR imaging. RESULTS: Foci of bright areas of white matter were found in all patients on T2-weighted images. The ADC values of the patients with ESRD, in white matter and gray matter before and after hemodialysis, were greater than those of the healthy controls (P < .005). Regarding the impact of hemodialysis, the ADC of frontal lobe white matter increased significantly after hemodialysis (1.09 +/- 0.11 versus 1.03 +/- 0.11, P = .036). We did not find the specific area of brain edema reported in posterior leukoencephalopathy and the osmotic demyelination syndrome. CONCLUSIONS: These results suggest that severe azotemia in end stage renal disease leads to interstitial brain edema reflected as increased ADC, and the further increased ADC reflects that edema associated with 1st hemodialysis is interstitial rather than cytotoxic in nature.


Asunto(s)
Azotemia/diagnóstico , Edema Encefálico/diagnóstico , Imagen de Difusión por Resonancia Magnética , Diálisis Renal , Uremia/diagnóstico , Adulto , Anciano , Azotemia/terapia , Encéfalo/patología , Diagnóstico Diferencial , Femenino , Glomerulonefritis/complicaciones , Glomerulonefritis/diagnóstico , Glomerulonefritis/terapia , Humanos , Masculino , Persona de Mediana Edad , Nefritis Intersticial/complicaciones , Nefritis Intersticial/diagnóstico , Nefritis Intersticial/terapia , Valores de Referencia , Sensibilidad y Especificidad , Uremia/terapia
11.
Neuroradiol J ; 20(3): 295-8, 2007 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-24299670

RESUMEN

Intracranial arteriovenous malformations are congenital vascular lesions characterized by localized arteriovenous shunting. Digital subtraction angiography is the gold standard for diagnosis. We herein report a case of intracranial arteriovenous malformations diagnosed by multi-detector computed tomographic (MDCT) angiography. The findings of MDCT angiography were confirmed by digital subtraction angiography. CT angiography might be a useful first-line screening tool, especially in an emergency situation.

12.
AJNR Am J Neuroradiol ; 27(4): 813-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16611770

RESUMEN

Multidetector CT (MDCT) angiography is an imaging technique that can provide high-resolution and high-contrast images; however, published reports of MDCT angiography in the evaluation of spinal vascular malformations are limited. We present 2 cases in which MDCT angiography led to diagnosis of a type I (spinal dural arteriovenous fistula) in one and type IVA (perimedullary spinal cord simple arteriovenous fistula fed by a single arterial feeder) spinal vascular malformation, both confirmed by conventional angiography. MDCT angiography can localize the feeding vessel and the fistula, thus greatly reducing the amount of time required for conventional angiography.


Asunto(s)
Angiografía/métodos , Malformaciones Vasculares del Sistema Nervioso Central/clasificación , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Médula Espinal/irrigación sanguínea , Médula Espinal/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Humanos , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Vértebras Torácicas
13.
Toxicol Appl Pharmacol ; 214(3): 244-52, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16480751

RESUMEN

Acrolein is a highly electrophilic alpha,beta-unsaturated aldehyde that is present in cigarette smoke. Heme oxygenase-1 (HO-1) is a cytoprotective enzyme activated by various such electrophilic compounds. In this study, the regulatory effects of acrolein upon the expression of HO-1 were investigated in endothelial cells (ECs). We demonstrate that acrolein induces the elevation of HO-1 protein levels, and subsequent enzyme activity, at non-cytotoxic concentrations. An additional alpha,beta-unsaturated aldehyde, cinnamaldehyde, was also found to increase HO-1 expression and have less cytotoxicity than acrolein. Moreover, acrolein-mediated HO-1 induction is abrogated in the presence of actinomycin D and cycloheximide. Nrf2 is a transcription factor involved in the induction of HO-1 through an antioxidant response element (ARE) in the promoter region of the HO-1 gene. We show that acrolein induces Nrf2 translocation and ARE-luciferase reporter activity. Acrolein was also found to induce the production of both superoxide and H2O2 at levels greater than 100 microM. However, with the exception of NAC, no antioxidant generated any effect upon acrolein-dependent HO-1 expression in ECs. Our present findings suggest that reactive oxygen species (ROS) may not be a major modulator for HO-1 induction. Using buthionine sulfoximine to deplete the intracellular GSH levels further enhanced the effects of acrolein. We also found that cellular GSH level was rapidly reduced after both 10 and 100 microM acrolein treatment. However, after 6 h of exposure to ECs, only 10 microM acrolein treatment increases GSH level. In addition, only the JNK inhibitor SP600125 and tyrosine kinase inhibitor genistein had any significant inhibitory impact upon the upregulation of HO-1 by acrolein. Pretreatment with a range of other PI3 kinase inhibitors, including wortmannin and LY294002, showed no effects. Hence, we show in our current experiments that a sublethal concentration of acrolein is in fact a novel HO-1 inducer, and we further identify the principal underlying mechanisms involved in this process.


Asunto(s)
Acroleína/toxicidad , Contaminantes Atmosféricos/toxicidad , Células Endoteliales , Hemo-Oxigenasa 1/biosíntesis , MAP Quinasa Quinasa 4/metabolismo , Acroleína/aislamiento & purificación , Animales , Western Blotting , Bovinos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Células Endoteliales/metabolismo , Activación Enzimática/efectos de los fármacos , Glutatión/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Contaminación por Humo de Tabaco/efectos adversos , Contaminación por Humo de Tabaco/análisis , Regulación hacia Arriba
14.
Life Sci ; 78(25): 2889-97, 2006 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-16378625

RESUMEN

Heme oxygenase-1 (HO-1) is a cytoprotective enzyme activated by various phytochemicals and we examined the ability of Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, to upregulate HO-1 expression in endothelial cells (ECs). We demonstrate that EGCG induces HO-1 expression in a concentration- and time-dependent manner. Furthermore, EGCG-mediated HO-1 induction was abrogated in the presence of actinomycin D and cycloheximide, indicating that this upregulation of HO-1 occurred at the transcriptional level. EGCG also upregulates Nrf2 levels in nuclear extracts and increases ARE-luciferase activity. Furthermore, EGCG is the most potent inducer of HO-1 expression of the different green tea constituents that we analyzed, but had no detectable cytotoxic effects over the 25-100 microM dosage range. The inhibition of intracellular ROS production by N-acetylcysteine (NAC), glutathione (GSH), superoxide dismutase (SOD), catalase and the mitochondrial complex I inhibitor, rotenone, results in a decrease in EGCG-dependent HO-1 expression. In addition, we determined that tyrosine kinase is involved in EGCG induction of HO-1 as this is abrogated by genistein. ECs treated with EGCG exhibit activation of Akt and ERK1/2. In addition, pharmacological inhibitors of phosphatidylinositol 3-kinase and MEK1/2, which are upstream of Akt and ERK1/2, respectively, attenuate EGCG-induced HO-1 expression. On the other hand, pretreatment of these cells with EGCG exerts significant cytoprotective effects against H2O2, suggesting that the induction of HO-1 is an important component in the protection against oxidative stress. Hence, EGCG is a novel phytochemical inducer of HO-1 expression and we further identify the principal underlying mechanisms involved in this process.


Asunto(s)
Antioxidantes/farmacología , Catequina/análogos & derivados , Quinasas MAP Reguladas por Señal Extracelular/fisiología , Hemo-Oxigenasa 1/biosíntesis , Fosfatidilinositol 3-Quinasas/fisiología , Transducción de Señal/efectos de los fármacos , Animales , Catequina/farmacología , Bovinos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Células Endoteliales/metabolismo , Inhibidores Enzimáticos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Estrés Oxidativo/efectos de los fármacos , Inhibidores de las Quinasa Fosfoinosítidos-3 , Regulación hacia Arriba
15.
Neuroradiology ; 46(3): 216-8, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14991257

RESUMEN

We report a case brachial plexus neuromuscular hamartoma (choristoma) in a 28-year-old man who complained of numbness of the left hand and forearm for several years. MRI revealed a circumscribed, rounded mass in the left brachial plexus. The patient is well 2 years after surgery, with no neurological deficit.


Asunto(s)
Plexo Braquial , Hamartoma/diagnóstico , Imagen por Resonancia Magnética , Enfermedades Neuromusculares/diagnóstico , Adulto , Plexo Braquial/patología , Plexo Braquial/cirugía , Hamartoma/cirugía , Humanos , Masculino , Enfermedades Neuromusculares/cirugía
16.
J Infect ; 46(4): 238-43, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12799149

RESUMEN

OBJECTIVES: A major outbreak of enterovirus 71 (EV71) in Taiwan in 1998 caused many severe cases and 78 deaths. Our purpose was to find reliable markers and early indicators of fatal EV71 central nervous system (CNS) infection. METHODS: From June 2000 to November 2001, 21 patients with hand foot mouth disease or herpangina with CNS infection were admitted to Kaohsiung Veterans General Hospital. All 21 had culture-confirmed EV71 infection or were EV71 IgM positive. Patients were divided into two groups: group I included the five fatalities at our institution and group II, the 16 surviving patients. RESULTS: Of the 21 infants and children with EV71 infection with CNS involvement, MR imaging studies were completed on 17, and 15 showed hyperintensity in the posterior portions of brain stem. All patients received intravenous immunoglobulin (IVIG) 1 g/day for two days and supportive care. Five patients rapidly deteriorated owing to irreversible hypotension and died. The other 16 patients recovered completely without sequel. In group I patients, the decrease of cardiac ejection function is significant and laboratory findings showed lower platelet count (P=0.0192). The mean of initial cTnI level for groups I and II was 10.6+/-11.6 and 0.48+/-0.55 ng/dl, respectively, higher in group I than in II (P=0.0019). CONCLUSION: We hypothesized that like patients with severe burns, those with severe EV-71 CNS meningoencephalitis have varying degrees of non-ischemic cardiac injury, manifesting as leakage of cTnI from myocytes into the circulation. EV-71 CNS meningoencephalitis likely to die with an early myocardial involvement evidenced by reduced ejection fraction and release of cTnI. We conclude that fatal EV71 CNS infection quickly leads to death due to severe encephalopathy associated with cardiomyopathy.


Asunto(s)
Enfermedades Virales del Sistema Nervioso Central/etiología , Infecciones por Enterovirus/complicaciones , Cardiopatías/etiología , Troponina I/sangre , Biomarcadores/sangre , Enfermedades Virales del Sistema Nervioso Central/mortalidad , Distribución de Chi-Cuadrado , Niño , Preescolar , Brotes de Enfermedades , Infecciones por Enterovirus/epidemiología , Femenino , Cardiopatías/epidemiología , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Factores de Riesgo , Estadísticas no Paramétricas , Taiwán/epidemiología
17.
Methods Inf Med ; 40(4): 331-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11552346

RESUMEN

OBJECTIVES: The purpose of this research is to develop an automatic medical diagnosis for segmenting nasopharyngeal carcinoma (NPC) with dynamic gadolinium-enhanced MR imaging. METHODS: This system is a multistage process, involving motion correction, head mask generation, dynamic MR data quantitative evaluation, rough segmentation, and rough segmentation refinement. Two approaches, a relative signal increase method and a slope method, are proposed for the quantitative evaluation of dynamic MR data. RESULTS: The NPC detection results obtained using the proposed methods had a rating of 85% in match percent compared with these lesions identified by an experienced radiologist. The match percent for the two proposed methods did not have significant differences. However, the computation cost for the slope method was about twelve times faster than the relative signal increase method. CONCLUSIONS: The proposed methods can identify the NPC regions quickly and effectively. This system can enhance the performance of clinical diagnosis.


Asunto(s)
Carcinoma/patología , Aumento de la Imagen , Imagen por Resonancia Magnética/métodos , Neoplasias Nasofaríngeas/patología , Procesamiento de Señales Asistido por Computador , Análisis de Varianza , Medios de Contraste , Gadolinio DTPA , Humanos , Estudios Retrospectivos , Sensibilidad y Especificidad
18.
J Formos Med Assoc ; 100(6): 370-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11480245

RESUMEN

BACKGROUND AND PURPOSE: Heightened interest in the early diagnosis and treatment of acute stroke challenges neuroimaging specialists to optimize available modalities and to develop new techniques for the evaluation of cerebrovascular disease. The purpose of this study was to evaluate the sensitivity of diffusion-weighted (DW) magnetic resonance (MR) imaging in detecting early small infarcts and in differentiating acute from nonacute small infarcts when conventional MR imaging demonstrates multiple small infarcts. METHODS: Thirty-eight consecutive patients with a clinical diagnosis of lacunar infarcts (20 men and 18 women, aged 50-79 yr) who underwent DW MR imaging within 3 days of symptom onset were enrolled in this study. All patients underwent both conventional fast spin-echo (FSE) MR imaging and DW MR imaging. Apparent diffusion coefficient (ADC) maps were also acquired. All patients had at least one of the following classic lacunar syndromes: pure motor hemiparesis, ataxic hemiparesis, dysarthria-clumsy hand, pure sensory stroke, and sensorimotor stroke. RESULTS: Thirty-six patients (40 acute lesions) had focal areas of high intensity on DW MR imaging associated with their clinical symptoms. Acute lacunar infarcts were seen on DW MR imaging as bright areas of decreased ADC ratio (range 0.31-0.85, mean 0.64). Lesion conspicuity with DW MR imaging was superior to that with FSE in 33 acute lesions. In four patients with small hyperacute (within 6 hours) infarcts, DW MR imaging was particularly sensitive for infarcts that were not visible on FSE sequences. The sensitivity of DW MR imaging and ADC map for acute lacunar infarcts was 95%, specificity 94%, positive predictive value 97%, negative predictive value 90%, and accuracy 95%. In 15 patients with both acute and nonacute old small infarcts, DW MR imaging and ADC map could easily distinguish the new infarct from adjacent old ones, although this distinction was difficult to make with FSE. CONCLUSIONS: DW MR imaging accompanied by ADC map is a sensitive diagnostic modality for hyperacute and acute lacunar infarcts. It is also sensitive in distinguishing fresh small infarcts from adjacent multiple old infarcts.


Asunto(s)
Infarto Encefálico/diagnóstico , Imagen por Resonancia Magnética , Enfermedad Aguda , Anciano , Encéfalo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
19.
Neuroradiology ; 43(7): 525-31, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11512579

RESUMEN

The most common cause of chorea-ballismus (CB) is a vascular lesion; it is also associated with nonketotic hyperglycaemia in diabetes mellitus (DM) and may be the first manifestation of this disorder. We describe the CT, MRI and proton MR spectroscopy (1H-MRS) of CB in eight patients. Six had hemichorea-hemiballismus (HC-HB) and two bilateral CB. Single-voxel (SV) 1H-MRS was performed using point-resolved spectroscopy (PRESS). Voxels were positioned in the basal ganglia of the patients and control subjects. PRESS was also used to obtain spectroscopic imaging (1H-MRSI) of the slice of interest in two patients. CT showed a slightly dense striatum in all the patients with CB, and T1-weighted images revealed high signal. The CB correlated well with the neuroimaging findings. SV 1H-MRS showed the mean (+/- SD) N-acetylaspartate (NAA)/ creatine (Cr) ratio to be 1.45 +/- 0.19 in HC-HB and 1.82 +/- 0.06 on the opposite normal side (P = 0.01). The choline (Cho)/ Cr ratio was 1.3 +/- 0.12 in HC-HB and 1.11 +/- 0.13 on the opposite normal side (P = 0.005). A lactate peak was seen in seven patients. The NAA/Cr ratio was 1.44 +/- 0.15 in bilateral CB and 1.74 +/- 0.16 in the controls (P = 0.017); the Cho/Cr ratios were 1.36 +/- 0.1 and 1.19 +/- 0.07 (P = 0.015). The low NAA/Cr suggests neuronal loss or damage and the high Cho/Cr probably indicates gliosis. The presence of lactate may suggest mild ischaemia due to acute vascular events during hyperglycaemia and underlying chronic focal cerebrovascular diseases in DM.


Asunto(s)
Ácido Aspártico/análogos & derivados , Corea/diagnóstico , Corea/etiología , Complicaciones de la Diabetes , Hiperglucemia/complicaciones , Espectroscopía de Resonancia Magnética , Anciano , Ácido Aspártico/metabolismo , Colina/metabolismo , Corea/metabolismo , Creatina/metabolismo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
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