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1.
J Perinatol ; 33(6): 486-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23719251

RESUMEN

A 22-week fetus presented with a large left ventricular aneurysm, 24 × 21 × 18 mm in size, detected by abnormal four-chamber view, and severe fetal hydrops with pericardial effusion, ascites and skin edema. The aneurysm was thin-walled, hypokinetic, and had enlarged with gestational age, causing compression of the lung. Although the left ventricular function had progressively impaired as expressed by increase in Tei index, hydrops had resolved by 32 weeks of gestation, probably because of maternal digoxin therapy and successful compensation by the right ventricle, as represented by retrograde blood flow in the distal aortic arch via the patent arterial duct. Because of the significant risk of severe cardiorespiratory failure, we transported the mother to a neonatal cardiac surgical center at 38 weeks of gestation. Indeed, the baby showed severe cardiopulmonary failure after birth, showing 100% of cardiothoracic ratio on the chest X-ray film, but was saved by the successful Dor procedure, including surgical resection of the aneurysm at 10 h of life. In this case, serial echocardiographic evaluation can allow us to monitor the hemodynamics and lead to successful postnatal management.


Asunto(s)
Ecocardiografía Doppler/métodos , Aneurisma Cardíaco/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Ventrículos Cardíacos/anomalías , Ventrículos Cardíacos/diagnóstico por imagen , Hidropesía Fetal/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Niño , Preescolar , Femenino , Estudios de Seguimiento , Aneurisma Cardíaco/cirugía , Cardiopatías Congénitas/cirugía , Insuficiencia Cardíaca/congénito , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/cirugía , Ventrículos Cardíacos/cirugía , Hemodinámica/fisiología , Humanos , Hidropesía Fetal/cirugía , Lactante , Recién Nacido , Masculino , Embarazo
2.
Kyobu Geka ; 62(10): 853-8; discussion 858-62, 2009 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-19764489

RESUMEN

BACKGROUND: We reviewed the preoperative hemodynamic factors, surgical results and intermediate outcome of Fontan procedure in hypoplastic left heart syndrome (HLHS). METHOD: From 1990 to 2006, 34 patients with HLHS completed Fontan procedure in our hospital. We compared preoperative hemodynamic factors, surgical results and postoperative course between HLHS group and functional single right ventricle (SRV) group who had undergone Fontan procedure. In addition, influence of the initial palliation [Norwood procedure with modified Blalock-Taussig (BT) shunt, Norwood procedure with right ventricle (RV)-pulmonary artery (PA) conduit and bilateral PA banding] to surgical results and postoperative course was investigated. RESULTS: The PA index was smaller in HLHS group than SRV group but there was no difference in surgical results and intermediate outcome between the 2 groups. Although age at Fontan was older in Norwood with BT shunt, preoperative hemodynamic factors, surgical results and intermediate outcome were similar between the 3 groups. CONCLUSION: Although the PA index in HLHS group was small, the surgical results of Fontan procedure in HLHS group were comparable with those in SRV group. The surgical result of Fontan procedure was satisfactory irrespective of the initial palliative procedure.


Asunto(s)
Procedimiento de Fontan , Síndrome del Corazón Izquierdo Hipoplásico/cirugía , Niño , Preescolar , Humanos , Resultado del Tratamiento
3.
Kyobu Geka ; 61(4): 262-7, 2008 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-18411687

RESUMEN

Surgical results and late outcome in 202 patients who had undergone arterial switch operation from 1984 to 1997 were investigated. Actuarial survival was 90.6% at 10 years and 90.0% at 20 years. Fifty-two patients (25.7%) underwent reoperation for pulmonary stenosis and 7 patients (3.5%) had aortic valve replacement. Freedom from re-intervention was 71.9% at 10 years and 60.4% at 20 years. Using xeno-pericardial patch for pulmonary reconstruction was strong predictor for postoperative pulmonary stenosis. Coronary ischemic event was rare but some patients showed electorocardiogram (ECG) change on exercise and hypoplastic left coronary artery. Cardiopulmonary function was almost normal in long term survivors.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Transposición de los Grandes Vasos/cirugía , Procedimientos Quirúrgicos Cardíacos/mortalidad , Ventrículo Derecho con Doble Salida/cirugía , Humanos
4.
Kyobu Geka ; 56(4): 299-303, 2003 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-12701193

RESUMEN

We reviewed our 58 experience of total cavopulmonary connection (TCPC) for children with visceral heterotaxy syndrome from 1992 to 1999. Surgical results, pre- and post-operative hemodynamics, and the incidence of cardiac-related events were compared between lateral tunnel method (LT) and extra-cardiac conduit method (EC). Overall survival rate was 89.6% in 8 years. Freedom from cardiac-related events was significantly lower in LT method compared with EC method (70.8% vs. 91.3% in 5 years and 67.8% vs. 91.3% in 8 years, p = 0.048). Extra-cardiac conduit TCPC following bi-directional Glenn shunt is the procedure of choice for children with visceral heterotaxy syndrome and functional single ventricle.


Asunto(s)
Procedimiento de Fontan , Puente Cardíaco Derecho , Ventrículos Cardíacos/anomalías , Situs Inversus/cirugía , Implantación de Prótesis Vascular/mortalidad , Niño , Preescolar , Procedimiento de Fontan/mortalidad , Puente Cardíaco Derecho/mortalidad , Ventrículos Cardíacos/cirugía , Hemodinámica , Humanos , Politetrafluoroetileno , Situs Inversus/mortalidad , Tasa de Supervivencia , Síndrome
5.
Int J Geriatr Psychiatry ; 16(12): 1129-35, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11748771

RESUMEN

UNLABELLED: BACKGROUND AND OBJECTIVES Geriatric depression is often thought to differ from that at other times of adulthood. Recently, several studies have shown that the incidence of white matter hyperintense lesions identified by brain MRI is higher in patients with geriatric depression than in healthy elderly subjects, but a consensus has not yet been reached on the relationship between the severity of white matter lesions and either cognitive impairment or depressive symptoms. METHOD: Forty-seven patients aged 50 to 75 years with major depression were divided into two groups based on age at onset of depression: early-onset (< 50 years) group (20 patients; mean age, 62.7 +/- 6.7) and late-onset (> or =50 years) group (27 patients; mean age, 65.6 +/- 5.4). The severity of hyperintense white matter lesions on MRI was classified by region, then a proton magnetic resonance spectroscopy ((1)H-MRS) focusing on the white matter of the frontal lobes, multidimensional neuropsychological tests and evaluation of depressive symptoms were conducted. RESULTS: The severity of the deep white matter lesions, the deterioration of cognitive function related to subcortical/frontal brain system and clinician-rated depressive symptoms were all more pronounced in the late-onset group compared with those in the early-onset group. It was further observed that the more severe the deep white matter lesions, the lower the levels of N-acetylaspartate/creatine. With the age of onset as the covariate, the patients with moderate deep white matter lesions had more pronounced cognitive impairment and clinician-rated depressive symptoms than those with none and/or mild lesions. CONCLUSION: These results suggest that subcortical/frontal type cognitive impairment and the persistence of depressive symptoms in geriatric depression is related to moderate deep white matter lesions more often complicated in the late-onset group. The (1)H-MRS findings were suggested to be a useful indicator of neuronal/axonal loss in the white matter of the frontal lobes which precedes cognitive impairment.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Ácido Aspártico/análogos & derivados , Encéfalo/fisiopatología , Trastorno Depresivo Mayor/diagnóstico , Metabolismo Energético/fisiología , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Anciano , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/psicología , Ácido Aspártico/metabolismo , Encéfalo/patología , Colina/metabolismo , Creatina/metabolismo , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/psicología , Femenino , Lóbulo Frontal/patología , Lóbulo Frontal/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Degeneración Nerviosa/diagnóstico , Degeneración Nerviosa/fisiopatología , Degeneración Nerviosa/psicología , Pruebas Neuropsicológicas , Valores de Referencia
6.
J Thorac Cardiovasc Surg ; 122(5): 879-82, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11689791

RESUMEN

OBJECTIVE: We evaluated a new cardiopulmonary bypass technique that allowed complete avoidance of circulatory arrest and deep hypothermia in the Norwood procedure for hypoplastic left heart syndrome. METHODS: A total of 10 patients were included in this study. The arterial line of the cardiopulmonary bypass circuit was divided in two in a Y shape; one branch was used for cerebral perfusion through the innominate artery and the other for lower body perfusion through the cannula inserted into the descending thoracic aorta. Moderate hypothermia (29 degrees C-31 degrees C rectal temperature) and high pump flow (150-180 mL. kg(-1). min(-1)) were used. A valveless conduit between the right ventricle and the pulmonary artery was used in 6 patients as an alternative pulmonary blood source to a conventional Blalock-Taussig shunt (n = 4). RESULTS: Circulatory arrest was completely avoided throughout the operation in all cases, and no complications from the new cardiopulmonary bypass technique were seen. Early deaths occurred in 3 cases. Neurologic deficits were not seen among the survivors, and the postoperative course was stable and uneventful, including satisfactory renal function. CONCLUSIONS: The Norwood procedure for hypoplastic left heart syndrome was successfully accomplished with complete avoidance of circulatory arrest by means of cerebral perfusion through the innominate artery combined with cannulation of the descending aorta. A conduit between the right ventricle and the pulmonary artery seems an excellent alternative pulmonary blood source, although right ventricular function needs to be carefully monitored.


Asunto(s)
Puente Cardiopulmonar , Síndrome del Corazón Izquierdo Hipoplásico/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Paro Cardíaco Inducido , Humanos , Recién Nacido
7.
Neurosci Lett ; 314(3): 143-6, 2001 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-11704304

RESUMEN

Fractal analysis has played an important role in various fields such as physics, biology and medicine. Recently, multifractal analysis based on generalized concepts of fractals has been applied to biological tissues composed of complex structures. Deep white matter hyperintensity (DWMH) on brain magnetic resonance imaging (MRI) is more often observed in patients with geriatric depression than in healthy elderly subjects, and its clinical significance is receiving attention. We applied multifractal analysis to white matter images on brain T2-weighted MRI in 62 patients with geriatric depression (50-75 years). The local fractal dimensions, alpha(max) and alpha(min), which serve as indices of complexity, and their difference, alpha(max) - alpha(min), were closely correlated with the macroscopic grading according to Fazekas classification, suggesting that multifractal analysis is useful for quantitative evaluation of DWMH on MRI.


Asunto(s)
Envejecimiento/patología , Corteza Cerebral/patología , Trastorno Depresivo/patología , Procesamiento de Imagen Asistido por Computador/métodos , Fibras Nerviosas Mielínicas/patología , Anciano , Corteza Cerebral/fisiopatología , Trastorno Depresivo/fisiopatología , Fractales , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Degeneración Nerviosa/patología , Degeneración Nerviosa/fisiopatología
8.
Brain Topogr ; 14(1): 57-68, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11599533

RESUMEN

Since the MEG inverse problem is ill-posed and admits many possible solutions, it is not possible to give it a single "true" answer. Therefore, we propose here to use a specific probabilistic algorithm to map the full probability distribution of the MEG sources with Markov Chain Monte Carlo methods. Using a Bayesian approach, the probability of the MEG solutions is expressed as the product of the likelihood by the prior probability. To compute the prior and constrain the MEG inverse problem resolution, MRI data are also acquired and automatically processed to determine the brain position and volume. We then use Parallel Tempering algorithm to estimate the full posterior probability and determine the likely solutions of the inverse problem. We illustrate the method with results obtained from the analysis of somatosensory data. This illustrates both the MRI processing for the prior computation, and how the knowledge of the full posterior probability distribution can be used to estimate the position of the sources, as well as their likely extension.


Asunto(s)
Algoritmos , Mapeo Encefálico/métodos , Encéfalo/fisiología , Electroencefalografía/métodos , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Adulto , Teorema de Bayes , Encéfalo/anatomía & histología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Cadenas de Markov , Modelos Neurológicos
9.
Jpn J Thorac Cardiovasc Surg ; 49(8): 497-503, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11552275

RESUMEN

OBJECTIVE: We evaluated long-term results of surgical correction of congenital cardiac anomalies in infancy. METHODS: We reviewed cases of 856 patients who underwent complete correction of major cardiac anomalies in the first year of life during last 24 years at our institution, and analyzed results. Surgery involved ventricular septal defect (n = 453), tetralogy of Fallot (n = 92), atrioventricular canal defect (n = 93), and complete transposition of the great arteries (n = 218). RESULTS: Operative mortality was 2.2% in ventricular septal defect, 0% in tetralogy of Fallot, 8.6% in atrioventricular canal defect, and 4.1% in complete transposition of the great arteries. Freedom from reoperation at 20 years was 96.5 +/- 2.0% and actuarial survival was 94.2 +/- 1.3% in ventricular septal defect. Freedom from reoperation at 15 years was 90.5 +/- 3.9% in tetralogy of Fallot and 86.6 +/- 4.4% in atrioventricular canal defect. Actuarial survival at 15 years was 97.8 +/- 1.6% in tetralogy of Fallot, 85.7 +/- 3.7% in atrioventricular canal defect, and 89.9 +/- 2.2% in complete transposition of the great arteries. Actuarial survival in complete transposition of the great arteries was significantly better in arterial than in atrial switch operations. CONCLUSIONS: Total correction of ventricular septal defect, tetralogy of Fallot, atrioventricular canal defect, and complete transposition of the great arteries in infancy was conducted safely, but the incidence of reoperation in late follow-up must be reduced.


Asunto(s)
Cardiopatías Congénitas/cirugía , Defectos de la Almohadilla Endocárdica/cirugía , Cardiopatías Congénitas/mortalidad , Defectos del Tabique Interventricular/cirugía , Humanos , Lactante , Recién Nacido , Tasa de Supervivencia , Tetralogía de Fallot/cirugía , Transposición de los Grandes Vasos/cirugía , Resultado del Tratamiento
10.
Nihon Geka Gakkai Zasshi ; 102(8): 566-72, 2001 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-11524833

RESUMEN

One hundred forty-two consecutive neonates or early infants with coarctation and interrupted aortic arch complex who underwent biventricular repair at the Fukuoka Children's Hospital between January 1991 and December 2000 were reviewed. One-stage repair was performed in 33 patients (35%) with coarctation complex and in 41 patients (85%) with interrupted aortic arch complex. The overall mortality rate was 6.1% in one-stage repair and 6.6% in two-stage repair of coarctation complex patients and 9.8% in one-stage repair and 28.6% in two-stage repair of interrupted aortic arch complex patients. The recoarctation rate was 5.3% in coarctation complex and 2.1% in interrupted aortic arch complex. All patients with recoarctation underwent successful catheter intervention and required no reoperation. In conclusion, one-stage repair of interrupted aortic arch and coarctation complex with the anterior approach resulted in good outcomes. Then descending aorta cannulation through a median sternotomy combined with the cerebral perfusion technique enables complete avoidance of circulatory arrest and is a useful technique. However, a two-stage procedure can be useful in the patients whose condition has deteriorated substantially or in whom intracardiac anomalies are severe.


Asunto(s)
Aorta Torácica/anomalías , Aorta Torácica/cirugía , Coartación Aórtica/cirugía , Circulación Extracorporea , Humanos , Lactante , Recién Nacido , Métodos
11.
Clin Neurophysiol ; 112(7): 1326-33, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11516745

RESUMEN

OBJECTIVE: To elucidate the temporal profile of interactions between sensory information from both hands in the somatosensory cortex. METHODS: Somatosensory evoked fields (SEFs), generated by stimulation applied to the right index finger after a preceding stimulation to the left index finger, were recorded using a whole head-type magnetoencephalography (MEG). The paired electrical stimuli were applied with a stimulation onset asynchrony (SOA) of 50, 100, 200, 300, or 400 ms. RESULTS: The mean SEF intensities in the primary somatosensory area (SI) of five subjects, which were evoked approximately 40 ms after the latter of the paired stimuli, were not significantly smaller than that evoked in the control condition when only the right finger was stimulated. In contrast, SEFs in the secondary somatosensory area (SII), generated approximately 100 ms after the stimuli, were suppressed when the paired stimuli were applied at an SOA of 100 ms (P<0.05, t test). In addition, SEFs at approximately 150 ms after the stimuli were significantly suppressed at SOAs of 50, 100 (P<0.05), 200, and 300 ms (P<0.1). CONCLUSION: Within a time window of approximately 300 ms, sensory information from the left finger significantly affected the SEFs generated by sensory inputs from the right finger. This time window may be required for the integration of sensory input.


Asunto(s)
Mano/inervación , Mano/fisiología , Corteza Somatosensorial/fisiología , Tacto/fisiología , Adulto , Estimulación Eléctrica , Potenciales Evocados Somatosensoriales/fisiología , Dedos/inervación , Dedos/fisiología , Lateralidad Funcional/fisiología , Humanos , Magnetoencefalografía , Masculino , Factores de Tiempo
12.
Kyobu Geka ; 54(8 Suppl): 643-6, 2001 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-11517525

RESUMEN

Between July 1988 and November 2000, 61 patients who were 11.3 +/- 3.8 years old underwent reoperation for obstructed extracardiac valved conduit at 7.0 +/- 2.1 years after Rastelli operation. The right ventricular outflow tract was reconstructed with nonvalved (n = 36) or valved (n = 9) conduit and Danielson's procedure (n = 16). One patient who underwent Danielson's procedure and concomitant aortic valve replacement died in 7 days after reoperation. Mean systolic pressure gradient across the right ventricular-pulmonary artery decreased from 58.6 mmHg to 14.6 mmHg. Re-reoperation was performed in 6 patients after Danielson's procedure for restenosis caused by contracture of xenograft outflow patches. There is no re-reoperation in patients with nonvalved conduit replacement. Postoperative pulmonary regurgitation by UCG was moderate in 12 patients with nonvalved conduit replacement and two with Danielson's procedure. In our experience, reoperation for obstructed extracardiac valved conduit after Rastelli operation is safe and nonvalved conduit replacement provides good midterm results.


Asunto(s)
Implantación de Prótesis Vascular , Procedimientos Quirúrgicos Cardíacos/métodos , Cardiopatías Congénitas/cirugía , Implantación de Prótesis de Válvulas Cardíacas , Adolescente , Niño , Ventrículos Cardíacos/cirugía , Humanos , Arteria Pulmonar/cirugía , Reoperación
13.
Ann Nucl Med ; 15(2): 123-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11448070

RESUMEN

To evaluate the usefulness of a combination of linearization and scatter-attenuation correction on 99mTc-bicisate (ECD)-single photon emission tomographic (SPECT) images, both cerebral blood flow (CBF)-positron emission tomographic (PET) images and ECD-SPECT images from fifteen patients with chronic cerebral infarction were acquired. We measured radioactivity counts in regions of interest (ROIs) on all sets of both images and obtained a 2D scattered graph between ECD-SPECT and CBF-PET data. To evaluate diagnostic accuracy, the sensitivity, specificity and accuracy of ECD-SPECT images were calculated by means of discriminant analysis. The same analysis was also performed on the ECD-SPECT images corrected by a combination of linearization and scatter-attenuation correction. An overall nonlinear relationship was observed between ECD-SPECT and CBF-PET. The sensitivity, specificity, and accuracy of ECD-SPECT images were 69.6%, 91.4% and 73.0%, and those of ECD images corrected by the combination of linearization and scatter-attenuation correction were 79.5%, 95.7% and 82.0% respectively. The clinically diagnostic accuracy of ECD-SPECT images corrected by the combined method apparently increased. So that the linearization with the scatter-attenuation method is useful for improving the diagnostic accuracy of ECD-SPECT images.


Asunto(s)
Encéfalo/diagnóstico por imagen , Cisteína/análogos & derivados , Compuestos de Organotecnecio , Tomografía Computarizada de Emisión de Fotón Único/métodos , Anciano , Infarto Cerebral/diagnóstico por imagen , Circulación Cerebrovascular , Enfermedad Crónica , Análisis Discriminante , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Radioisótopos de Oxígeno , Radiofármacos , Dispersión de Radiación , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión , Tomografía Computarizada de Emisión de Fotón Único/estadística & datos numéricos
14.
Jpn Circ J ; 65(7): 599-602, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11446492

RESUMEN

A questionnaire was used to survey the experience of 8 Japanese institutions with percutaneous transluminal aortic valvuloplasty (PTAV) in children. Among 99 procedures reported in 88 patients, sufficient data for analysis was obtained from 76 procedures in 72 patients. In those 76 procedures the pressure gradient decreased significantly from 68+/-25 (20-140) to 33+/-22 (0-100) mmHg (p<0.01), whereas aortic regurgitation (AR) increased at least one grade in 26 cases (34%). None of the parameters analyzed in this study were predictors of an increase in AR. The reduction in pressure gradient was judged as good in 44 of the 76 procedures (58%). A larger ring diameter, larger balloon diameter and larger ratio balloon diameter/the normal predicted diameter of the aortic valve ring significantly contributed to an effective reduction of pressure gradient. Follow up data (mean interval, 4 years) was available for 26 of 39 clinically effective procedures. AR progressed at least 1 grade in 11 (42%), and the pressure gradient re-developed to more than 50mmHg in 2 cases (8%). In Japan, PTAV has been accepted as a useful procedure for valvular aortic stenosis in children, but progressive AR or re-development of the pressure gradient is not uncommon even after clinically effective PTAV.


Asunto(s)
Angioplastia Coronaria con Balón/normas , Estenosis de la Válvula Aórtica/terapia , Adolescente , Angioplastia Coronaria con Balón/efectos adversos , Insuficiencia de la Válvula Aórtica/etiología , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/fisiopatología , Presión Sanguínea , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Pronóstico , Encuestas y Cuestionarios , Resultado del Tratamiento
15.
J Neurol Neurosurg Psychiatry ; 71(2): 250-3, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11459905

RESUMEN

In a patient with the interval form of carbon monoxide (CO) poisoning diffusion weighted MRI and proton magnetic resonance spectroscopy (1H-MRS) were serially performed immediately after the appearance of delayed sequelae (the 23rd day after exposure). During the period in which few clear findings were evident on MRI T2 weighted images, a high signal area in the cerebral white matter and relative decrease in the apparent diffusion coefficient (ADCav) were already apparent on diffusion weighted images, with these findings thought to sensitively reflect the tissue injury associated with the onset of sequelae. The decrease in relative ADCav persisted until the 38th day after exposure. Subsequently, ADCav gradually increased, and in the cerebral white matter showed higher values in the 118th day after exposure than immediately after the onset of sequelae. During this period, on 1H-MRS choline containing compounds showed persistently high values throughout the course, with N-acetylaspartate depletion and the appearance of a lactate peak later in the course. These findings, with regional specificity in the cerebral white matter, reflect the developmental process of the white matter lesions in the interval form of CO poisoning in which demyelination progresses leading to neuronal necrosis. Serial diffusion weighted imaging plus 1H-MRS measurements are useful in determining the tissue damage and long term outcome of delayed sequelae associated with the interval form of CO poisoning.


Asunto(s)
Encéfalo/patología , Intoxicación por Monóxido de Carbono/patología , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Protones , Factores de Tiempo
16.
Nihon Geka Gakkai Zasshi ; 102(4): 342-7, 2001 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-11344688

RESUMEN

The clinical results after surgical treatment of congenital valve disease have improved due to the use of several recently developed techniques. The replacement of tendinous cords using E-PTFE sutures has allowed the indications for the repair of mitral valve prolapse to be extended. The Ross procedure has made it possible to replace the aortic valve associated with small aortic annulus. However, replacement with a prosthetic valve remains the only option if repair is not possible or fails. Prosthetic valve replacement in the pediatric age-group remains challenging in patients with a small valve annulus. A number of techniques can be employed in such cases, including enlargement of the aortic annulus and translocation of the prosthetic valve in the left atrium, although there are limits on the size of the prosthesis. Further improvement of surgical techniques is necessary, along with the development of prosthetic valves using more nearly physiological materials.


Asunto(s)
Insuficiencia de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Insuficiencia de la Válvula Mitral/cirugía , Estenosis de la Válvula Mitral/cirugía , Válvula Tricúspide/anomalías , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/congénito , Estenosis de la Válvula Aórtica/congénito , Niño , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/congénito , Estenosis de la Válvula Mitral/congénito , Válvula Tricúspide/cirugía
17.
IEEE Trans Biomed Eng ; 48(5): 533-42, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11341527

RESUMEN

We investigated the usefulness of probabilistic Markov chain Monte Carlo (MCMC) methods for solving the magnetoencephalography (MEG) inverse problem, by using an algorithm composed of the combination of two MCMC samplers: Reversible Jump (RJ) and Parallel Tempering (PT). The MEG inverse problem was formulated in a probabilistic Bayesian approach, and we describe how the RJ and PT algorithms are fitted to our application. This approach offers better resolution of the MEG inverse problem even when the number of source dipoles is unknown (RJ), and significant reduction of the probability of erroneous convergence to local modes (PT). First estimates of the accuracy and resolution of our composite algorithm are given from results of simulation studies obtained with an unknown number of sources, and with white and neuromagnetic noise. In contrast to other approaches, MCMC methods do not just give an estimation of a "single best" solution, but they provide confidence interval for the source localization, probability distribution for the number of fitted dipoles, and estimation of other almost equally likely solutions.


Asunto(s)
Algoritmos , Magnetoencefalografía , Modelos Estadísticos , Teorema de Bayes , Cadenas de Markov
18.
AJNR Am J Neuroradiol ; 22(5): 922-7, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11337338

RESUMEN

BACKGROUND AND PURPOSE: Chronic hypoperfusion may cause ischemic insult in the deep white matter. The magnetization transfer phenomenon is associated with the amount and constitution of myelin. The purpose of this study was to assess the usefulness of the magnetization transfer ratio (MTR) for detecting vasculometabolic abnormalities on positron emission tomography (PET) studies in patients with unilateral severe stenosis of the internal carotid artery (ICA). METHODS: MTR maps and PET data-including regional cerebral blood flow (rCBF), regional cerebral metabolic rate of oxygen (rCMRO(2)), and regional oxygen extraction fraction (rOEF)-were investigated in 13 patients with unilateral severe stenosis of the ICA. The same regions of interest were selected in the white matter both on MTR maps and PET scans. The areas were classified into three groups based on MTR values (group 0, MTR >47.22%; group 1, MTR = 45.77% to 47.22%; group 2, MTR <45.77%), and the relationship between MTR and PET data was analyzed by means of both absolute values and asymmetric index (AI). RESULTS: Abnormal values could not be detected in the areas classified as group 0. The areas classified as group 1 were characterized by absolutely normal values of rCMRO(2) and increased rOEF with AI, which was assessed as viable and reversible on the PET study. The areas classified as group 2 showed decreased rCMRO(2) with absolute values, which was considered irreversible in PET. A significant overall linear correlation was found between MTR and rCMRO(2) values. CONCLUSION: Using the MTR technique to classify ischemic damage into three groups (normal, reversible, and irreversible), we found a significant correlation between the reduction of MTR and that of rCMRO(2) in white matter with ICA stenosis. We believe that the MTR technique may partly replace PET data in the assessment of ischemic injury.


Asunto(s)
Estenosis Carotídea/diagnóstico , Imagen por Resonancia Magnética , Anciano , Anciano de 80 o más Años , Encéfalo/metabolismo , Estenosis Carotídea/metabolismo , Estenosis Carotídea/fisiopatología , Circulación Cerebrovascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Oxígeno/metabolismo , Tomografía Computarizada de Emisión
19.
Ann Thorac Surg ; 71(2): 715-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11235741

RESUMEN

Ectopia cordis is a very rare and often fatal disease. We report a successful surgery case of thoracoabdominal ectopia cordis with univentricular heart. This patient underwent a three-stage Fontan procedure, a right-modified Blalock-Taussig shunt at the age of 1 month, bidirectional Glenn shunt and pulmonary arterioplasty at 2 years 8 months, and finally a total cavopulmonary connection at 4 years. This patient was discharged from the hospital in good condition and has been doing well since. Thus, ectopia cordis is not a contraindication for a Fontan operation.


Asunto(s)
Procedimiento de Fontan , Cardiopatías Congénitas/cirugía , Preescolar , Femenino , Estudios de Seguimiento , Puente Cardíaco Derecho , Ventrículos Cardíacos/anomalías , Humanos , Lactante , Reoperación
20.
Colloids Surf B Biointerfaces ; 20(4): 347-353, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11166545

RESUMEN

Electrophoretic mobility and aggregation in suspensions of three types of microspheres (Ms 1, Ms 2 and Ms 3) are studied at different pH, ionic strengths and temperatures of the medium. Here Ms 1 is a core particle composed of poly(N-isopropylacrylamide-co-styrene). Ms 2 is a core-shell microsphere consisting of Ms 1 as the particle core covered with a surface layer of poly(N-isopropylacrylamide) hydrogel. Ms 3 is also a core-shell microsphere composed of MS-1 covered with a surface layer of poly(N-isopropylacrylamide-co-acrylic acid) hydrogel. The charge density zN and the softness parameter 1/lambda of the microspheres were obtained from the electrophoretic mobility data on the basis of an electrokinetic theory of soft particles. It is shown that when zN is large, suspensions of microspheres are always stable, showing no aggregation. When zN is small, the suspensions are stable for large 1/lambda but show strong aggregation for small 1/lambda.

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