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If a difficulty arises during birth, due to a maternal or fetal anomaly, acute or chronic, asphyxia of the fetal brain constitutes a greater risk, because it could result in the destruction of neurons and the possibility of evolving towards a Ischemic Hypoxic Encephalopathy with long -term sequelae. This review highlights the most recent scientific aspects but at the same time it offers an essential margin of knowledge regarding pathophysiology, diagnosis and treatment, as well as offering a perspective on the future of clinical care of ischemic hypoxic encephalopathy.Si una dificultad sobreviene durante el nacimiento de un niño, por una anomalía materna o fetal, aguda o crónica, la asfixia del cerebro fetal constituye un riesgo mayor, porque ella podría dar como resultado la destrucción de las neuronas y la posibilidad de evolucionar hacia una encefalopatía hipóxico isquémica con secuelas a largo plazo. En esta revisión se resaltan los aspectos científicos más recientes pero a la vez se ofrece un margen de conocimiento imprescindible en cuant o a la patofisiología, diagnóstico y tratamiento, así como también se ofrece una perspectiva sobre el futuro de la atención clínica de la encefalopatía hipóxico isquémica.

Hypoxic-ischemic encephalopathy is a clearly recognizable clinical syndrome of in term newborns due to fetal asphyxia at birth. The incidence is 1.5 (95% CI 1.3 to 1.7) but it ranges from 1-8 and 25 out of every 1000 born in developed and developing countries, respectively. The most frequent causes are detachment of the placenta, prolapse of the umbilical cord and uterine rupture. The diagnostic criteria include partial or total incapacity for the newborn to cry and breath at birth even when stimulated, requiring assisted ventilation in the delivery room, Apgar5 in 5 and 10 minutes, acidemia (pH ≤ 7 and / or bases deficit ≥ 12 mmol/l), alterations of the conscience and the reflexes of Moro, grasping and suction, muscular stretching and muscle tone. The clinical forms are mild, moderate and severe. In the mild forms, the recovery is total in three days without, or with minimal, neurodevelopmental alterations. The moderate and severe forms cause permanent neurological deficits and neurodevelopmental alterations (48%) or death (27%). The regular or amplitude integrated EEG and the magnetic and spectroscopic magnetic resonance imaging performed between 24 and 96 hours and 7 and 21 days after birth, respectively, have a high diagnostic and prognostic value. Induced hypothermia (33.5° C for 72 hours) is recommended before 6 hours old. The result is a decrease in mortality (from 35% to 27%) and morbidity (from 48% to 27%).

El propósito de la pesquisa neurometabólica en el recién nacido es la detección temprana de desórdenes cuyo tratamiento precoz previene daños permanentes. Las enfermedades actualmente posibles de una pesquisa masiva en el recién nacido normal son la fenilcetonuria, el hipotiroidismo congénito, la galactosemia, la hiperplasia adrenal congénita, la fibrosis quística, la deficiencia de biotinidasa, enfermedad de la orina de jarabe de arce, la anemia drepanocítica, la homocistinuria. Los instrumentos más usados para estas evaluaciones son el espectrómetro de masa y los estudios genéticos.The purpose of neurometabolic screening is the earliest possible detection of treatable disorders. The disorders currently offered to general population screening are phenylketonuria, congenital hypothyroidism, galactosemia, congenital adrenal hyperplasia, cystic fibrosis, biotinidase deficiency, maple syrup urine disease, sickle cell disease, homocystinuria. The methods used for these evaluations are mass spectroscopy and genetic testing.

La miastenia gravis juvenil (MGJ) es un trastorno crónico auto inmune en el cual existen anticuerpos séricos que al unirse a los receptores de acetilcolin nicotínicos de la membrana muscular de la placa motora alteran la transmisión neuromuscular. El resultado es fatiga muscular precoz con progresión a la parálisis durante estados de contracción muscular iterativos (movimientos) o sostenidos (posturas) y más raramente parálisis permanente durante el reposo. Los músculos inervados por los nervios craneales, especialmente los extraoculares y elevadores de los párpados, tienen más tendencia a la debilidad muscular persistente que los inervados por otros pares craneales y las extremidades. Las formas clínicas de presentación son generalizadas, oculares y respiratorias. El diagnóstico se sospecha mediante la anamnesia, la fatiga anormal se comprueba mediante el examen físico y la estimulación eléctrica iterativa del nervio que inerva al músculo afectado pero no paralizado. Se corrobora mediante la administración de inhibidores de la acetilcolin esterasa (IACE) que al aumentar la cantidad de acetilcolin en la hendidura sináptica, corrigen la fatiga o la debilidad muscular transitoriamente. Se hace el diagnóstico de certeza mediante la demostración sérica de anticuerpos contra los receptores de acetilcolin (ACRA). El tratamiento es a largo plazo sintomático con IACE y etiopatogénico con inmunosupresores, plasmaféresis, gamma globulina endovenosa y timectomía. El curso es crónico. La remisión espontánea o después de tratamiento sintomático o etiopatogénico ocurre entre 1-10 años respectivamente. La mortalidad es prácticamente nula aun durantes las crisis miastenias gracias a la educación de padres, pacientes y público en general sobre el tema, al desarrollo del sistema de respuesta rápida de auxilio domiciliario y las unidades de cuidados intensivos y el empleo de la ventilación asistida profiláctica, plasmaféresis y administración endovenosa de gamma globulina.Juvenile myasthenia gravis is a chronic autoimmune disorder which occurs when serum antibodies combine with nicotinic acetylcholine receptors at the muscle membrane of the motor endplate imparing the neuromuscular transmission. It results in early muscle fatigability with progression to a complete paralysis during repetitive muscle contraction (movements) or steady muscle contraction (postures), and less common persistent paralysis at rest. The cranial nerves, mainly the one innervating the extraoccular and palpebral levator, are the most susceptible to permanent weakness and paralysis at rest. Initial clinical presentations are generalized, ocular and respiratory forms. The diagnosis is suspected through medical history of abnormal fatigability and corroborated by physical examination, repetitive nerve stimulation of an affected but not complete paralyzed muscle, correction of fatigability by the intravenous administration of acetylcholine esterase inhibitors, and by the presence of serum acetylcholine receptors antibodies (ACRA). The long term treatment is symptomatic (acetylcholine inhibitors) and etiopathogenic (immunosupresor drugs, plasmapheresis, intravenous gamma globulin and thymectomy. Spontaneous or post symptomatic and etiopathogenic treatment remissions occur from 1 to 10 years. Fatality is rare but children are at high risk during myasthenia crisis.

Las enfermedades del sueño se clasifican en disomnias, parasomnias, enfermedades del sueño asociadas con enfermedades médicas y psiquiátricas, y las propuestas enfermedades del sueño. Solo las parasomnias han sido estudiadas como tales en el recién nacido. Las parasomnias que ocurren en el recién nacido son el síndrome de apnea infantil del sueño, el síndrome de hipoventilación congénita central, el síndrome de muerte infantil súbita, y el mioclono neonatal benigno del sueño. Bajo el término de síndrome de apnea infantil del sueño se agrupan tres entidades: (1) el síndrome de apnea del prematuro, (2) el síndrome de evento que pone en peligro la vida del niño asociado con apnea, y (3) la apnea obstructiva del sueño. El síndrome de hipoventilación central congénito puede estar asociado a otras enfermedades del sistema autónomo tales como la enfermedad de Hirschsprung (síndrome de Haddad) y la dismotilidad esofágica, y a tumores del sistema nervioso simpático, especialmente al neuroblastoma. La implementación de la posición supina para dormir y el no fumar en los hogares ha disminuido la frecuencia del síndrome de muerte súbita infantil a 0.85 por 1.000 nacimientos. El mioclono neonatal benigno del sueño debe considerarse en todo recién nacido con un examen normal entre los episodios de mioclonia cuyos episodios sólo ocurren durante el sueño. Esta entidad puede confundirse con status epilepticus, porque los eventos pueden asociarse a aumentos de la frecuencia cardíaca. El uso de las benzodiazepinas puede prolongar la duración de los eventos mioclónicos.Sleep disorders are classified in dyssomnias, parasomnias, sleep disorder associated with medical and psychiatric disorders and proposed sleep disorders. Only the parasomnias have been studied as such in the newborn period. The parasomnias that occur in this age group are infant sleep apnea, congenital central hypoventilation syndrome, sudden infant death syndrome, and benign neonatal sleep myoclonus. Infant sleep apnea includes three entities: (1) apnea of prematurity, (2), apparent life threatening episodes with apnea and (3) obstructive sleep apnea. Congenital central hypoventilation syndrome can be associated with other autonomic system illness, such as Hirschsprung disease (Haddad syndrome) and neuroblastoma. The implementation of the supine sleep position and smoking free homes has diminished the frequency of sudden infant death syndrome. Benign neonatal sleep myoclonus should be considered in all newborns with a normal exam between the episodes when they always occur during sleep. This entity may be mistaken for status epilepticus, because it is associated with increases in heart rate. Benzodiazepines prolongs the duration of the episodes.

Los potenciales evocados (PE) son procedimientos neurofisiológicos más sensibles que específicos, objetivos, fidedignos, reproducibles y seguros que se emplean para evaluar la integridad de las vías sensoriales y motoras periféricas y centrales. La integridad de estas vías se determina midiendo la latencia de los eventos eléctricos producidos por estímulos adecuados y registrados después de ser promediados digitalmente. Las indicaciones médicas y quirúrgicas incluyen condiciones en las cuales el diagnóstico, la determinación del riesgo de secuelas neurológicas en pacientes comatosos y anestesiados y la determinación del curso de la enfermedad y respuesta al tratamiento no se pueden definir con el examen neurológico y otras pruebas neurodiagnósticas.Evoked potentials (EP) are more sensitive than specific, safe, objective and reproducible neurophysiologic techniques to assess integrity of peripheral and central sensory and motor pathways. The integrity of pathways are determined by measurement the latency of the recorded and digitally averaged electrical events elicited after adequate stimulation. EP are medically and surgically recommended in conditions in which the diagnoses, determination of neurological outcome in comatose and under anesthesia patients, and determination of the course and evaluation of treatment are uncertain with neurologic examination and other neurodiagnostic studies.

The purpose of this report is to discuss the association of brachial plexus palsy and congenital deformations. We reviewed all charts of patients less than 1 year of age with obstetrical brachial plexus palsy evaluated by one of the authors (IA) between January 1998 and October 2005 at Miami Children's Hospital Brachial Plexus Center. Of 158 patients with obstetrical brachial plexus palsy, 7 had deformations (4.4%). Deformations were present in 32% of patients delivered by cesarean section, but in only 2% of patients delivered vaginally. The deformations were ipsilateral, involving the chest in two patients, distal arms in two patients, proximal arm in one patient, ear in one patient, and the leg in one patient. All patients with deformations had unilateral Erb's palsies. None had a history of maternal uterine malformation. Two presumptive mechanisms of injury, one causing the deformation (compressive forces) and one causing brachial plexus palsy at the time of delivery (traction forces), were present in all cases. The higher incidence of deformation in patients with obstetrical brachial plexus palsy born by cesarean sections and the presence of two presumptive mechanisms in all of the cases presented here raises the possibility that fetal deformations are a risk factor for obstetrical brachial plexus palsy.

This article reviews the authors' experience over the last decade in the multidisciplinary management of children with brachial plexus birth injuries. When compared with the results of a study of 91 children who received nonoperative treatment, the results of surgical intervention can improve the functional outcome in properly selected infants.

Focal upper extremity neuropathies are common in neonates. The brachial plexus is the most common site involved. Brachial plexus injuries may involve different structures, thus producing different clinical presentations: complete brachial plexus palsy, Duchenne-Erb palsy, upper-middle trunk brachial plexus palsy, Klumpke palsy, fascicular brachial plexus palsy, and bilateral brachial plexus palsy. The causes of brachial plexus palsy are obstetric injury, intrauterine compression, humeral osteomyelitis, hemangioma, exostosis of the first rib, neck compression, and neoplasm. The differential diagnosis of brachial plexus palsy includes pseudoparesis, amyoplasia congenita, congenita varicella syndrome, and neurological lesions at other neuroanatomical levels. The cause and the degree of injury dictate the prognosis. The prognosis of obstetric brachial plexus injury is usually good.

Two children developed severe cognitive and behavioral deterioration suggestive of a degenerative disease while being treated with sodium valproate for idiopathic, localization-related epilepsy with centrotemporal spikes. Magnetic resonance imaging revealed marked central and generalized cortical and cerebellar atrophy. In both patients, clinical symptoms and signs cleared in a few weeks following valproate withdrawal. The magnetic resonance imaging appearance improved within 3 months in 1 of the patients and normalized in both after 6 and 12 months. No metabolic changes were associated with the clinical or imaging abnormalities. Although the mechanism of this rare idiosyncratic complication of valproate therapy is unknown, we advocate discontinuing valproate therapy in all epileptic patients with neuromental deterioration or brain atrophy of unknown etiology.

Preferential involvement of certain central nervous systems areas by specific viruses provides a valuable guide to the selection of antiviral agents. We report a neonate that developed opsoclonus 7 days prior to the diagnosis of herpes simplex type 2 cerebellitis. The course of the opsoclonus paralleled the clinical course and radiologic evolution of the infection. The purpose of this report is to describe opsoclonus as a possible early sign of herpes simplex type 2 central nervous system infection. ( J Child Neurol 2003;18:356—358).

The association of cervicothoracic extradural arachnoid cysts and obstetric brachial plexus palsy has not previously been reported. We report two patients with this association. The first patient is a 9-month-old boy with left obstetric brachial plexus palsy that developed bilateral leg weakness at 6 months of age owing to compression of the spinal cord by a C6 to T8 left cervicothoracic extradural arachnoid cyst. The second patient is a 3-year-old girl with bilateral brachial plexus palsy and spastic paraparesis who had magnetic resonance imaging at 3 days of age that showed intraspinal cord injury and a cervicothoracic extradural arachnoid cyst compressing the spinal cord. We believe that the association of cervicothoracic epidural arachnoid cysts and obstetric brachial plexus palsy in these patients was causal and recommend that the possibility of a cervicothoracic epidural arachnoid cyst be considered in patients with brachial plexus palsy and evidence of spinal cord injury. ( J Child Neurol 2002;17:770—772).

Transient neonatal myasthenia gravis is a postsynaptic neuromuscular transmission defect occurring in 21% of infants born to women with active (and, less commonly, in remission) acquired myasthenia gravis. Although passive-transfer acetylcholine receptor (AChR) antibodies are found in the majority of these newborns, their pathogenic role is questionable because only some infants are symptomatic. Pathogenesis in infants without AChR antibodies is unknown. There is still no biologic marker for prenatal identification of this subpopulation of newborns, although HLA typing may be a promising tool. Sucking, swallowing, and respiratory difficulties are the most common presenting signs in the first day of life. Final diagnosis is done when administration of acetylcholinesterase agents transiently corrects the neuromuscular transmission defect. Serum AChR antibody titers follow the same pattern as their mothers. Supportive management and anticholinesterase agents prior to feedings are necessary in about 80% of patients. In the majority of infants the condition resolves spontaneously. ( J Child Neurol 1992;7:135-141).

The loading dosage of intravenous valproate required to achieve a desired serum concentration in neonates is not known. Two neonates with seizures received loading doses of intravenous valproate over 30 minutes. Serum valproate concentrations were measured 45 minutes and 3 hours after initiation of the infusion. Both neonates had received phenobarbital and phenytoin before the loading infusions. In the first patient, a loading dose of intravenous valproate of 10 mg/kg increased the 45-minute postinfusion serum valproate concentration to 41 μg/mL with a 3-hour postinfusion serum valproate concentration of 33 μg/mL. In the second patient, a loading dose of 25 mg/kg increased the 45-minute postinfusion serum valproic acid concentration to 100 μg/mL with a 3-hour postinfusion serum valproic acid concentration of 78 μg/mL. We found that each 1 mg/kg of intravenous valproate increased the 45-minute and 3-hour postinfusion serum valproic acid concentrations by approximately 4 μg/mL and 3 μg/mL, respectively. We suggest that these figures be used to calculate the desirable loading dose of intravenous valproate in neonates until larger studies are conducted. The volume of distribution and the serum clearance of valproate were approximately 0.245 L/kg and 25 mL/h/kg, respectively. (J Child Neurol 2000;15:827-829).

Two patients with neonatal onset of arm weakness resulting from neoplastic involvement of the brachial plexus who were initially considered to have obstetric brachial plexus palsies are reported. The first patient was a 7-day-old female who presented with a left supraclavicular mass that was first detected at 2 days of age and left proximal arm weakness. The weakness involved the whole arm within 3 days. The mass was a malignant rhabdoid tumor. The second patient was a 28-month-old male who presented with slowly progressive right arm weakness, which began at 3 weeks of age, and episodes of scratch marks on the arm that began at 4 months of age. Magnetic resonance imaging revealed a plexiform neurofibroma of the brachial plexus. The features that are suggestive of a brachial plexus palsy caused by a neoplasm rather than of obstetric brachial plexus palsy include the following: the onset of weakness after the first day of age, with a progressive course; a history of a normal delivery and birth weight; the absence of signs of a traumatic injury or injuries; the appearance before 7 days of age of a growing supraclavicular mass without radiographic evidence of a clavicular fracture; and recurrent scratch marks on the weak arm.

We report the ictal brain single photon emission computed tomographic (SPECT) findings in two neonates. One neonate had hypoxic-ischemic encephalopathy, a disorganized discontinuous electroencephalogram (EEG) background, lethargy, seizures, and brainstem release phenomena. A brain SPECT was performed during a brainstem release phenomenon characterized by a 34-second sustained tonic posture of the right arm and chewing. It did not reveal focal cerebral hemisphere hyperfusion. The second neonate had hemimegalencephaly, low-voltage irregular EEG background, and seizures. A brain SPECT was performed during a seizure characterized by a 32-second sustained tonic posture of the right arm. It revealed focal hyperperfusion in the posterior region of the left hemisphere. The brain SPECT findings in these patients indicate that despite clinically similar events, brainstem release phenomena and seizures have different perfusion characteristics, and refute the theory that brainstem release phenomena are due to epileptic foci in the cerebral hemispheres undetectable by EEG. (J Child Neurol 2000;15:56-58).

Juvenile myasthenia gravis is a chronic autoimmune disorder which occurs when serum antibodies combine with nicotinic acetylcholine receptors at the muscle membrane of the motor endplate imparing the neuromuscular transmission. It results in early muscle fatigability with progression to a complete paralysis during repetitive muscle contraction (movements) or steady muscle contraction (postures), and less common persistent paralysis at rest. The cranial nerves, mainly the one innervating the extraoccular and palpebral levator, are the most susceptible to permanent weakness and paralysis at rest. Initial clinical presentations are generalized, ocular and respiratory forms. The diagnosis is suspected through medical history of abnormal fatigability and corroborated by physical examination, repetitive nerve stimulation of an affected but not complete paralyzed muscle, correction of fatigability by the intravenous administration of acetylcholine esterase inhibitors, and by the presence of serum acetylcholine receptors antibodies (ACRA). The long term treatment is symptomatic (acetylcholine inhibitors) and etiopathogenic (immunosupresor drugs, plasmapheresis, intravenous gamma globulin and thymectomy. Spontaneous or post symptomatic and etiopathogenic treatment remissions occur from 1 to 10 years. Fatality is rare but children are at high risk during myasthenia crisis.

Sleep disorders are classified in dyssomnias, parasomnias, sleep disorder associated with medical and psychiatric disorders and proposed sleep disorders. Only the parasomnias have been studied as such in the newborn period. The parasomnias that occur in this age group are infant sleep apnea, congenital central hypoventilation syndrome, sudden infant death syndrome, and benign neonatal sleep myoclonus. Infant sleep apnea includes three entities: (1) apnea of prematurity, (2), apparent life threatening episodes with apnea and (3) obstructive sleep apnea. Congenital central hypoventilation syndrome can be associated with other autonomic system illness, such as Hirschsprung disease (Haddad syndrome) and neuroblastoma. The implementation of the supine sleep position and smoking free homes has diminished the frequency of sudden infant death syndrome. Benign neonatal sleep myoclonus should be considered in all newborns with a normal exam between the episodes when they always occur during sleep. This entity may be mistaken for status epilepticus, because it is associated with increases in heart rate. Benzodiazepines prolongs the duration of the episodes.

Evoked potentials (EP) are more sensitive than specific, safe, objective and reproducible neurophysiologic techniques to assess integrity of peripheral and central sensory and motor pathways. The integrity of pathways are determined by measurement the latency of the recorded and digitally averaged electrical events elicited after adequate stimulation. EP are medically and surgically recommended in conditions in which the diagnoses, determination of neurological outcome in comatose and under anesthesia patients, and determination of the course and evaluation of treatment are uncertain with neurologic examination and other neurodiagnostic studies.

Brain single-photon emission computed tomography (SPECT) findings during clinical and subclinical seizures were compared in two neonates with hemimegalencephaly. Interictal and ictal brain SPECT were performed in two neonates. The ictal studies were performed during a clinical seizure in one neonate and during a subclinical seizure in another neonate. They revealed similar focal hemispheric hyperperfusion at the electroencephalographic seizure foci in both cases. The similar perfusion patterns imply that clinical and subclinical seizures place similar metabolic demands on the cerebral tissue involved in the generation of electroencephalographic seizures in neonates with cerebral dysgenesis and suggest that clinical and subclinical seizures should be treated similarly in this population.

We report an electroclinical pattern considered characteristic of benign familial neonatal convulsions (BFNC) in two neonates without BFNC. Both neonates were products of uncomplicated pregnancies, labor, and deliveries. The cause of the seizures was not established. There was no family history of seizures or epilepsy. Seizures started on the second and third days after birth. Ten seizures were captured by continuous video-EEG telemetry. The electroclinical events began with generalized tonic posturing coinciding with the appearance of diffuse attenuation of the EEG activity. After several seconds, bilateral clonic movements accompanied by bilateral repetitive sharp waves or spikes occurred in the EEG. One patient had normal development; the other became autistic. We conclude that the electroclinical pattern occurring in BFNC can occur in other types of neonatal seizures.

Obstetrical brachial plexus injury occurs when the forces preventing the stretch of the brachial plexus are overcome by the forces stretching it. This report describes an 8-day-old male delivered by uncomplicated cesarean section with right obstetrical brachial plexus palsy and congenital arm atrophy. The patient had a history of decreased right arm movement detected by fetal ultrasound at 18 to 20 weeks of gestation. The purpose of this article is to report that stretching of brachial plexus at birth sufficient to produce a plexus injury may occur in a patient with a vulnerable plexus even in the absence of traction during delivery.

Early surgical removal of a dysplastic hemisphere appears to be beneficial for neonates with hemimegalencephaly and medically resistant seizures. We analyzed the changes in the cerebral regional oxygen saturation index in a neonate with tuberous sclerosis and right hemimegalencephaly (1) during seven episodes of right hemisphere electroencephalographic status epilepticus with and without clinical manifestations and (2) after right hemispherectomy. The cerebral regional oxygen saturation index demonstrated marked fluctuations and progressive decline in both hemispheres during the episodes and normal values in the remaining hemisphere after surgery. We speculate that decreased oxygenation of the nonepileptic cerebral hemisphere in patients with hemimegalencephaly and medically resistant seizures can contribute to the production of global neurologic impairments in these patients and that the benefits of early hemispherectomy are due to the improved oxygenation of the nondysplastic hemisphere following surgery. (J Child Neurol 2004; 19:394-396).

The muscular dystrophies (MDs) are inherited or de novo gene mutation disorders of sarcolemma-associated proteins or nuclear membrane-associated proteins. They are manifested by progressive striated muscle weakness and wasting. Cardiac and central nervous system abnormalities may be present. MD phenotypes vary in terms of defective gene, mode of inheritance, age of onset, distribution of muscle involvement, and severity. Clinical diagnosis is confirmed by direct or indirect mutation analysis and gene product defect detection in frozen muscle samples by immunohistochemistry and Western blot. The majority of the adolescents with MD are already aware of the nature and course of their condition, which adds a significant psychosocial pathology to their physical disability. Management includes: (1). prevention of new cases by preconception counseling, prenatal testing, and neonatal screening; (2). prevention and treatment of skeletal deformities, cardiac and respiratory insufficiencies, and psychological and psychiatric disturbances; and (3). education, counseling, and support to patients, parents, siblings, caretakers, and teachers. Management is better achieved with a multidisciplinary approach. Although there is no cure, oral steroids may preserve transitorily acceptable muscle function. Despite the initial failure with myoblast transfer therapy, advances in molecular genetic and stem cell implants are promising.

High levels of methemoglobinemia can cause tissue hypoxia and cyanosis. We report the case of a 7-month-old girl with pulmonary dysplasia receiving inhaled nitric oxide who had cyanosis caused by methemoglobinemia after prolonged use of a eutectic mixture of local anesthetics cream.

Neurophysiological evaluation of children with traumatic peripheral nervous system injury is accomplished with electromyography, motor and sensory nerve conduction studies, and somatosensory and motor-evoked potentials. Preoperative neurophysiological tests are performed if motor deficits persist for more than 3 months. Evidence of reinnervation on these neurophysiological tests predates clinical recovery by weeks, hence they help determine the site of the lesion and provide objective measures for selecting candidates for surgical exploration. Intraoperative neurophysiological tests help to identily and confirm the integrity of nerves and to develop the optimal surgical strategy. Postoperative evaluations every 3 to 6 months may determine efficacy of treatment.

Introduccion. Los escolares con trastorno por deficit de atencion/hiperactividad combinado (TDAH-C) presentan alteraciones de la funcion ejecutiva (FE) que mejoran mediante la administracion de metilfenidato o con el entrenamiento de la memoria de trabajo. Objetivo. Determinar el efecto del entrenamiento de las FE sobre sus alteraciones y sobre el TDAH-C en preescolares. Sujetos y metodos. Criterio de inclusion: distribucion aleatoria, ninos de 2 a 4 anos de edad, afectados de TDAH-C, incluidos entre el uno de julio de 2004 y el 30 de junio de 2005, con examen neurologico normal, sin enfermedades cronicas, que no estaban recibiendo tratamiento farmacologico a largo plazo y cuyos padres estaban de acuerdo en entrenar o no entrenar a sus hijos. Los padres completaron el cuestionario del DSM-IV para determinar la presencia o la ausencia de TDAH-C y las FE se evaluaron mediante la Dimensional Change Card Sort Task en la primera evaluacion y una vez al ano durante tres anos. El promedio de puntuacion de la inatencion, hiperactividad/impulsividad y FE en los grupos entrenado o no entrenado se analizaron estadisticamente mediante la t de Student. Resultados. De 25 ninos, 13 recibieron entrenamiento. La incidencia de TDAH-C descendio a 16 casos (64%), 6 ninos (24%) con entrenamiento y 10 ninos (40%) sin el. La incidencia de TDAH-C fue del 50, 40 y 25% y del 100, 66,66 y 100% despues de uno, dos y tres anos con entrenamiento o sin el. El promedio de puntuacion de la inatencion fue de 8,25, 8,4 y 7 antes del entrenamiento y de 6, 5,8, y 5,5 despues de uno, dos y tres anos. El promedio de la hiperactividad/impulsividad fue de 8,5, 8,4 y 7,75 antes del entrenamiento y de 5,75, 5,6 y 5,25 despues de uno, dos y tres anos, y el de las FE, de 5,2, 4,8 y 5,5 antes del entrenamiento y de 8,5, 10 y 9,5 despues de uno, dos y tres anos de entrenamiento. El grado de mejora de la inatencion, de la hiperactividad/impulsividad y de las FE fue estadisticamente significativo con el entrenamiento de las FE durante uno, dos y tres anos (p = 0,013, 0,002, 0,0249). Conclusiones. Los preescolares con TDAH-C y alteraciones de las FE deberian recibir entrenamiento de estas durante, como minimo, tres anos desde el momento del diagnostico para mejorar su condicion.

Introduccion. La encefalitis herpetica (EH) es una enfermedad infecciosa focal del sistema nervioso central (SNC) reconocida mundialmente como grave. Desarrollo. La epidemiologia esta bien establecida en paises desarrollados. Se presenta en pacientes mayores de 3 meses. No esta bien determinado el mecanismo por el que el virus se reactiva y penetra en el SNC. El diagnostico precoz es determinante para la instauracion temprana del tratamiento en los primeros cuatro dias del proceso infeccioso, con lo que se puede lograr aumentar en mas de un 50% la posibilidad de supervivencia. Se insta tener una sospecha importante ante un paciente con sintomas de encefalitis, especialmente si presenta manifestaciones neurologicas focales, incluidas las del ambito neuropsiquiatrico. El metodo diagnostico no invasivo por excelencia es el estudio de resonancia magnetica cerebral con alta sensibilidad en las primeras 24-48 horas tras el inicio de las manifestaciones clinicas. La determinacion de ADN viral en el liquido cefalorraquideo por reaccion en cadena de la polimerasa es el metodo de mayor sensibilidad y especificidad disponible para el diagnostico. El tratamiento efectivo es aciclovir por via endovenosa: 30 mg/kg/dia en tres dosis. Conclusion. La encefalitis producida por el virus herpes es una temible enfermedad por la alta mortalidad y devastacion de las condiciones de vida de los supervivientes. Se propone estimular la sospecha clinica de la EH de manera que se inicie un tratamiento farmacologico incluso mientras se realizan las pruebas diagnosticas. Planteamos la evaluacion neuropsicologica temprana y el seguimiento de las manifestaciones de secuelas focales relacionadas con las regiones frontotemporales.

Objetivo. Revisar el desarrollo, la anatomia y la fisiologia de las funciones ejecutivas (FE) en condiciones normales y patologicas. Desarrollo. Las FE consisten en varios procesos mentales disenados para resolver problemas mentales y medioambientales complejos con eficiencia y el beneplacito de la persona y la sociedad. Las FE incluyen inhibicion de la conducta y la informacion irrelevante, memoria de trabajo no verbal, memoria de trabajo verbal, autorregulacion de las emociones, motivaciones y grado de alerta, planeamiento, tomar decisiones, automonitorizacion del proceso y autoevaluacion de los resultados de la accion tomada. Las estructuras anatomicas involucradas incluyen la corteza prefrontal y sus areas aferentes y eferentes. Los neurotransmisores implicados son la dopamina y la norepinefrina y, en menor grado, la acetilcolina y la serotonina. Conclusiones. Se han encontrado alteraciones de una o varias de las FE en ninos y adolescentes con trastorno por deficit de atencion e hiperactividad, sindrome de Tourette, enfermedad bipolar, depresion, trastorno obsesivo-compulsivo, autismo y postraumatismo cerebral.

Introduccion. El proposito de este articulo es revisar el papel del neurologo en el manejo de los recien nacidos a termino con accidentes vasculares encefalicos (AVE) (lesiones debidas a una subita obstruccion o ruptura de un vaso intracraneal). Con este fin se revisaron las fuentes bibliograficas (PubMed) mediante la busqueda de los terminos `stroke´ y `term neonate´. Desarrollo. Los AVE se dividen en hematomas e infartos. Los hematomas deben clasificarse de acuerdo con su localizacion; estructura vascular envuelta (arteria, vena o seno), el tipo de anomalia vascular (aneurisma, malformaciones venosas, telangiectasia) y la causa de la extravasacion de la sangre (ruptura de la pared vascular o hipo-coagulacion). La clasificacion de acuerdo con la localizacion incluye: compartimentos (supra e infratentoriales), espacios -extraaxial (epidural, subdural o aracnoideo) o intraaxial (parenquima o ventriculos)- y regiones -parietal, temporal, talamica, etc.-. Los infartos se clasifican de acuerdo con factores vasculares y parenquimatosos; los factores vasculares son el tipo de estructura vascular envuelta, causa de la obstruccion -extramural, mural o intramural (embolo o trombo)-; los factores parenquimatosos son el tipo de infarto -palido o hemorragico- y la localizacion de este. Los pacientes con procesos embolicos requieren ecografia del corazon y del cuello. La posibilidad de causas multiples debe sospecharse. Se deben realizar estudios de coagulacion. La cirugia puede ser necesaria en determinados casos. En pacientes con cardioembolismo se sugiere la anticoagulacion en infartos palidos y pequenos. Conclusion. La funcion del neurologo en estos pacientes consiste en clasificar el evento, guiar las investigaciones y decidir el tratamiento.

The authors report regional differences in perfusion within the affected hemisphere with relatively interictal hypoperfusion and ictal hyperperfusion of the seizure focus in a neonate with hemimegalencephaly. These ictal/interictal changes in perfusion are characteristic of an eleptogenic foci in older patients. These findings are illustrated.

Objetivos. La terapia mas popular y de mayor demanda entre los padres de los pacientes con paralisis cerebral (PC) es la inhalacion de oxigeno hiperbarico (OH). En este trabajo nos propusimos revisar la bibliografia sobre OH en la PC para determinar su eficacia y riesgo. Revisamos las referencias en MEDLINE-PubMed (1996-2003) bajo los encabezamientos PC y OH. Desarrollo. Encontramos 16 referencias: cinco articulos (un estudio piloto no controlado, dos de un solo estudio controlado, un comunicado de complicaciones y una revision) y 11 cartas al editor. El estudio controlado demostro una mejoria significativa similar en la escala de las funciones motoras groseras, autocontrol, atencion auditiva y memoria visual de trabajo en ninos con PC tratados con OH (O2 = 100%; 1,75 AA) y placebo (O2 = 21%; 1,3 AA). Las complicaciones fueron otitis media barometrica (OMB) en un 50% de los ninos tratados con OH y un 25% del grupo placebo. Los resultados fueron interpretados por los autores y el Comite Cientifico de la Academia Americana de Paralisis Cerebral y Medicina del Desarrollo, debido al efecto de participacion. La Sociedad de Medicina Submarina e Hiperbarica de Sudafrica recomendo no emplear OH en ninos con PC, en base a los resultados de este estudio controlado. Tres cartas al editor interpretaron los resultados como que ambos tratamientos fueron efectivos. Conclusiones. No encontramos evidencias cientificas que justifiquen el empleo de OH en ninos con PC. Los efectos indeseables fueron OMB.

Introduccion. Los trastornos cognitivos (TC) transitorios en ninos con epilepsia rolandica benigna (ERB), la mas comun de las epilepsias parciales idiopaticas (EPI), son secundarios a descargas epileptiformes interictales (DEI). Objetivos. Determinar la incidencia y factores de riesgo de los TC persistentes en escolares con EPI antes, durante y despues de la administracion de antiepilepticos (AE). Pacientes y metodos. Criterio de inclusion: edad de 6 a 12 anos, EPI, control con AE durante dos 2 anos y seguimiento durante cinco anos. Evaluaciones: inteligencia (Wechsler-III), aprendizaje (Wechsler), nivel academico (Woodcock-Johnson) y atencion/conducta (O?Conners-R). Variables: sexo, edad de comienzo, tipo de EPI, intervalo entre la primera crisis y comienzo del AE, resultado del EEG y tipo de AE. Analisis: ji cuadrado. Resultados. No se observaron TC antes de comenzar los AE ni durante los dos anos con AE y sin crisis clinicas ni EEG. 14 pacientes tuvieron trastornos del aprendizaje, inatencion, impulsividad, hiperactividad, baja tolerancia y agresividad durante la remision; 12 (85,71%) con epilepsia del lobulo temporal: seis (50%) con DEI en el lado izquierdo (hemisferio dominante izquierdo), dos (16,67%) con DEI en el derecho (hemisferio dominante izquierdo), dos (16,67%) en ambos lobulos temporales y dos (14,29%) con ERB. La resonancia magnetica cerebral fue normal. Conclusiones. Los ninos con epilepsia del lobulo temporal idiopatica con DEI en el hemisferio dominante presentan mayor riesgo que el resto de los pacientes con EPI a sufrir TC. Se recomienda eliminar no solo las cisis, sino tambien las DEI, para evitar estos trastornos.

Objetivo. Revisar la embriologia y los aspectos clinicos de la holoprosencefalia y la agenesia del cuerpo calloso en el periodo neonatal. Desarrollo. A los 24 dias de gestacion, el neuroporo rostral se cierra. Alrededor de los 74 dias de gestacion, comienzan a cruzarse los primeros axones en la region dorsal de la placa comisural destinada a convertirse en el cuerpo calloso. Este adquiere su configuracion final (aunque no su tamano final) a los 115 dias de gestacion. Los trastornos de diverticulacion conducen a la holoprosencefalia, que ocurre por una disfuncion del mesodermo rostral y cuya etiologia es heterogenea. El riesgo de holoprosencefalia en neonatos de madres con diabetes mellitus gestacional es del 1 al 2%. La agenesia del cuerpo calloso no asociada a holoprosencefalia constituye un trastorno del desarrollo del la linea media del telencefalo. Los trastornos metabolicos asociados con agenesia total o parcial del cuerpo calloso son la deficiencia de la dehidrogenasa piruvica y la hiperglicinemia sin cetosis. El pronostico de la agenesia del cuerpo calloso detectado durante el parto viene determinado por la presencia de anormalidades fuera del sistema nervioso central y la presencia de otras anormalidades en el mismo. Conclusiones. El conocimiento de la embriologia del sistema nervioso central es necesario para entender las manifestaciones radiologicas de la holoprosencefalia y la agenesia de cuerpo calloso. La evaluacion del neonato con estas malformaciones requiere estudios geneticos y metabolicos.

Generalized neonatal hypotonia implies a pathologically decreased postural tone involving at least the extremities, trunk and neck occurring during the first month of life. The gestational age of the neonate, the behavioral state of the neonate at the time of the examination, and the possibility of pseudoparalysis (due to generalized pain) should be considered when evaluating a neonate for the possibility of generalized hypotonia. The evaluation of neonates with hypotonia should be guided by the characteristic of the muscular dynamic reflexes, primitive reflexes, the relation between the degree of hypotonia and weakness and findings during several maneuvers (traction, ventral and horizontal suspension, plantar response and response to forward displacement from a lying position). Possible sites of pathology in neonates with hypotonia include: (1) brain, (2) brain stem, (3) cervical spine, (4) cerebellum, (5) lower motor neurons in the brain stem and spine; (6) nerve, (7) myoneural junction, and (8) muscles.

Introduction. Continuous display four-channels EEG monitoring and near-infrared spectroscopy (NIRS) are relatively new and valuable techniques used for continuous brain monitoring in the neonatal period. Supporting the value of continuous display four-channels EEG monitoring in the evaluation of neonates with paroxysmal motor events is a study recently conducted at Miami Children's Hospital. Development. In this study 30 events were captures in 88 hours of simultaneous continuous display four-channels EEG monitoring and continuous video-EEG telemetry recording in five patients. Fourteen of the events were consider epileptic and 16 were considered non epileptic after evaluation of the continuous display four-channels EEG monitoring printed epochs. Results. The continuous video-EEG telemetry confirmed the diagnosis for all the events. Several studies attest to the usefulness of NIRS in neonates and in older children with pathologies similar to those seeing in neonates. Conclusions. 1. NIRS is the best method to monitor regional cerebral oxygen saturation; 2. Regional cerebral oxygen saturation values are primarily those of the venous circulation in the subcortical white matter below the sensor; 3. Values of regional oxygen saturation should be considered not independently but only relative as a change over time; 4. Decreased regional cerebral oxygen saturation may be a sign of impending or established hypoxemia or hypotension, increased cerebral metabolic demands, or a cerebral oxygenation or perfusion problem that involve only brain, and 5. NIRS should be used in conjunction with arterial oxygen saturation and pressure monitoring (to detect hypoxemia and hypotension), with EEG to detect increased cerebral metabolic demands (electroencephalographic seizures) and with anterior cerebral artery Doppler ultrasound to detect perfusion (decreased flow velocity) and oxygenation (constant flow velocity) problems that involve only the brain.

Objective. The purpose of this review is to demostrate the value and limitations ofneurophysiological evaluation of children with peripheral neuropathy. Development. The neurophysiological evaluation (NPE) is an extensionof the neurologic examination. The NPE has a high diagnostic sensitiviy but lacks etiologic specificity. The NPE includes motor and sensory nerve conduction velocity studies (NCV), needle EMG, somatosensory evoked potential (SEP) and motor evoked potential (MEP). The NCV allows to determine the component of the peripheral nerve fiber involved (axon and/or myelin), type of fibers affected (motor and/or sensory), the location of the lesion (proximal and/or distal) and the pattern of the nerve involvement (segmental or continuos). The EMG allows to determine the presence and degree ofdenervation and reinervation. Conclusions. The combination of NCV, EMG, SEP and MEP allow: 1. To localize a lesion to the diferent regions of the peripheral nervous system (preganglionic and/or postganglionic segments of dorsal root, ventral root, spinal nerve, plexus and peripheral nerves); 2. To determine severity and prognosis; 3. To select candidates for reconstructive exploratory surgery; and 4. To determine treatment efficacy and/or natural course of the disease.

INTRODUCTION The positive effect of methylphenidate on children and adults with ADHD is well known. However, the effect of discontinuation of methylphenidate at adolescence onset on adult s ADHD is unknown. Objective. To determine the effect of discontinuation of methylphenidate at adolescence onset on adult s attention deficit, hyperactivity, impulsivity and functional disabilities. PATIENTS AND METHODS Adults and their parents, spouses and/or friends were requested to fill out the same criteria diagnosis form filled out by their parents and teachers before (7 years of age), during (7.5 years of age) and at the end of treatment (12 years of age). They took methylphenidate (0.1 0.5 mg/kg/day) from age 7 to 12 years because ADHD. Inattention, hyperactivity, impulsivity and functional disability were statistically analyzed by the paired sample method before, during at the end of treatment and at age 27 years. RESULTS Methylphenidate used for 5 years (7.5 12 years of age) improved significantly (p< 0.001) the average score for inattention, hyperactivity, impulsivity and functional impairment compared to pre (7 year of age) and post (27 years of age) treatment. The discontinuation of methylphenidate for 15 years (12 27 year of age) deteriorate significantly the average score for inattention and functional impairment when pre adolescent and adult values were compared (p< 0.001). CONCLUSIONS The results strongly suggest that methylphenidate must be used throughout the adulthood to avoid the degree of inattention and functional disability found in this study.

Landry-Guillain-Barre-Sthrol Syndrome (LGBS) is an acute autoimmune monophasic and selflimiting polyradiculoneuropathy affecting patients aged 19 to 59 years (1.7/100,000/year) more than below 18 year of age (0.8/100,000/ year). Diagnostic criteria require: I. Progressive motor weakness of more than one limb, and II) absent muscle stretch reflexes. Features that strongly support the diagnosis are: 1. Cease of progression of weakness by 4 weeks, relative symmetrical involvement ofthe limbs, presence ofmild sensory symptoms or signs, involvement of cranial nerves VII (50%) more than IX, X, III, IV and VI, recovery within 2 to 3 weeks after progression stop, presence of autonomic dysfunction, and absent of fever at onset; 2. Cerebral spinal fluid elevation of protein after first week of symptoms and less than 10 mononuclear leukocytes/mm 3 except HIV seropositive patients (

INTRODUCTION AND DEVELOPMENT Evoked potentials evaluation of children with central nervous system developmental disorders o dysfunctions is better than clinical and imaging assessment for determination of: 1) conceptional age, 2) auditory and visual threshold, 3) integrity of sensory pathways, 4) neurologic motor outcome, and 5) course and evaluation of treatment of neurometabolic disorders. CONCLUSIONS However, it is not the same for predicting or making the diagnosis of the majority of primary developmental disorders (autism, receptive and expressive language disorders, learning disability, attention deficit disorders and Gilles de la Tourette syndrome.

INTRODUCTION A literature review using the term Ohtahara syndrome and early infantile epileptic encephalopathy revealed 51 cases. DEVELOPMENT The characteristics of these cases were: 1) early onset of seizures; 2) tonic seizures; 3) poor response to treatment; 4) mental retardation; 5) poor prognosis; 6) burst-suppression EEG pattern; 7) evolution to West syndrome, and 8) multiple causes. These characteristics are non specific. No cause was found in most cases. The onset of seizures was between 7 hours and 86 days of age. The most frequent brain imaging abnormality was diffuse atrophy. ACTH was effective in a few cases and hemispherectomy was successful in one case. CONCLUSION We believe that Ohtahara syndrome and early myoclonic encephalopathy are the same entity.

Over the last two decades the surgical treatment of epilepsies has become a commonly used and effective method for the treatment of intractable epilepsy. However, because of its wide use in various types of centers throughout the world the methodology involved varies significantly throughout the centers. With this article we propose the bases from which a multidisciplinary team of numerous centers can eventually develop an effective and acceptable international protocol for the surgical treatment of the epilepsies and the classifications of the centers.

Introduction The objectives of the neurophysiological evaluation of infants with brachial plexus palsy are to determine the time of occurrence of the lesion, to locate the lesion and to determine its course. Methods and conclusions These objectives are achieved by studying affected upper extremity muscles by needle electromiography (EMG) and affected nerves by motor and sensory conduction studies. EMG is performed in the first week of life in those patients with brachial plexus palsy of unknown etiology to determine the age of the lesion for medico-legal reasons. EMG is performed before surgery for tendon transfer in the selected muscles to assure that they are normal. EMG and motor and sensory conduction studies are performed at the age of 3 and 6 months in infants with less than 4 muscle weakness to determine candidates for surgical exploration. Motor and sensory nerve conduction studies are performed intraoperative to determine the functional status of the affected axons and the best surgical procedure (neurotization, neurolysis and/or neuroma resection and homologous nerve graft).

OBJECTIVE AND METHODS A variety of surgical procedures exist for early repair of the nerve injury in obstetrical brachial plexus palsy, including neuroma excision and nerve grafting, neurolysis and neurotization. Secondary deformities of the shoulder, forearm, and hand can similarly be reconstructed using soft tissue and skeletal procedures. This review describes our surgical approach to maximize the ultimate functional outcome in infants and children with obstetrical brachial plexus palsy.

Introduction The brachial plexus originates from C5 to T1 spinal segments. The brachial plexus includes the ventral ramus, trunks, divisions, cords and branches. Development and conclusions Brachial plexus injuries produce clinical syndromes. The Duchenne-Erb syndrome is the most frequent presentation of obstetric brachial plexus injury. The differential diagnosis of brachial plexus palsy include decreased arm movements due to pain, or weakness caused by a lesion of the nervous system outside in the brachial plexus, or by a lesion in the brachial plexus due to non-obstetrical causes. Management of these patients initially includes considering the possibility of clavicular and humeral fractures and posterior subluxation of the shoulder; and subsequently considering the possibilities of subscapularis muscle contraction or posterior shoulder subluxation in patients that develop internal rotation contracture of the shoulder; or flexion, pronation or supination contracture in patients with forearm deformation. Treatment consist of physical therapy, administration of botulinum toxin, electrical stimulation, neurolysis, nervatization, removal of neuromas and nerve grafting, treatment of fractures and subluxation, release of muscle contracture and tendon transplantation.