Paraparesia espástica tropical y atrofia cerebelosa / Tropical spastic paraparesis and cerebelar atrophy

Resumen Antecedentes: El virus linfotrópico T tipo I (HTLV-I) origina la paraparesia espástica tropical (PET) en el 3% de los infectados, afectando predominante mujeres. Excepcionalmente la PET puede asociar un síndrome vestibular central y atrofia cerebelosa. Propósito: Presentar un nuevo y excepcional caso de paraparesia espástica y atrofia cerebelosa. Sugerir una interpretación patogénica del predominio femenino en esta patología Paciente: Mujer de 20 años de talla baja y menuda, infectada con HTLV-I durante la lactancia. Aproximadamente a los 15 años inició un síndrome ataxo-espástico progresivo, con grave alteración de la marcha, posteriormente agregó daño cognitivo y atrofia cerebelosa en la RM. Se constató a su ingreso una elevada carga viral y altos niveles de proteína Tax. Fue tratada con 4 mg betametasona diarios durante 10 días, que mejoraron la marcha. Conclusión: La PET es una axonopatía de la vía motora central, originada por la crónica perturbación del transporte axoplásmico, atribuible a la presencia de elevados niveles de la proteína Tax del virus. Circunstancialmente este aumento de Tax logra dañar axones del centro oval (deterioro cognitivo) o del vermis cerebeloso (síndrome vestibular central). La PET afecta mayoritariamente a mujeres 3:1, prevalencia que hace aparecer a las mujeres con una mayor vulnerabilidad en su SNC. Sin embargo, esta aparente minusvalía, sería debida a un aumento en la concentración de Tax en el SNC de ellas, causado por la adversa relación entre peso corporal y cantidad absoluta de Tax, que fue evidente en nuestra paciente, quien dio la clave para esta hipótesis.

Background: Lymphotropic Virus Type I (HTLV-I) causes Tropical Spastic Paraparesis (PET) in 3% of infected patients; in whom have been described exceptionally associated a central vestibular syndrome and cerebellar atrophy. Those alterations of CNS are predominating in women. Purpose: To present a new case of the exceptional form of spastic paraparesis and cerebellar atrophy. To suggest a pathogenic interpretation of female predominance in this pathology Patient: A 20-year-old woman of small size, infected with HTLV-I during lactation. Approximately at 15 years of age he started a progressive ataxo-spastic syndrome, later cognitive damage and cerebellar atrophy were added. Upon admission, high viral load and high levels of Tax protein, leukemoid lymphocytes and Sicca syndrome were observed. Conclusion: PET is an axonopathy of the central motor pathway, originated by a chronic disturbance of axoplasmic transport, attributable to the action of elevated levels of Tax protein in the CNS. In addition axons of the oval center (cognitive impairment) or the cerebellar vermis (central vestibular syndrome) are occasionally damaged. Although PET mainly affects 3: 1 women, this prevalence increases in accordance with the increase of neurological damage. The apparent greater vulnerability of the CNS in women would be due to the higher concentration of Tax in the CNS of them, originated in the adverse relationship between body weight and absolute amount of Tax, which was evident in our patient, who gave the key to this hypothesis.

[Cerebral ptosis. Analysis of six cases]. / Investigación clínica de la ptosis cerebral. Presentación de seis nuevos casos.

BACKGROUND: Cerebral ptosis is understood as the bilateral paralysis of eyelid elevation linked to a stroke or hemorrhage of the middle cerebral artery (MCA). It is a transient condition, independent of the evolution of the lesion. AIM: To analyze six patients with the condition. PATIENTS AND METHODS: Report of five women and one male aged 42 to 72 years. RESULTS: All suffered an infarction or hemorrhage in the territory of the middle cerebral artery of the non-dominant hemisphere and developed a bilateral palpebral ptosis. The recovery started after the fourth day. At the tenth day, eye opening was effortless and did not require frontal help, despite the persistence of hemiplegia. CONCLUSIONS: Cerebral ptosis is a mimetic dysfunction of a specific non-injured area of the cerebral cortex, originated from a nearby parenchymal damage such as the middle cerebral artery of the same hemisphere. Cerebral ptosis expresses the inhibition of the voluntary eyelid elevation center, of prefrontal location in the non-dominant hemisphere.

Arteritis de células gigantes en el sistema vertebrobasilar, isquemias cerebelo-occipitales y parálisis III par: caso clínico / Giant cell arteritis of the vertebrobasilar system, posterior ischemia and palsy of the third nerve: report of one case

Giant cell arteritis is the most common vasculitis in patients aged over 50 years. We report an 89-year-old woman with significant weight loss and persistent frontal-occipital headaches lasting two months. The neurological examination at admission identified a decrease in visual acuity of the left eye, paralysis of the third cranial nerve of the right eye and alterations of body motility without objective signs of damage of the motor or sensitive pathways. Magnetic resonance imaging showed changes of the temporal artery wall and in both vertebral arteries, as well as bilateral cerebellar and occipital ischemic lesions. The Doppler ultrasound of the temporal arteries was compatible with Giant cell arteritis. Treatment with steroids was started. While receiving oral prednisone, the patient suffered new infarcts of the posterior territory, documented with a CAT scan.

[Spinal subacute combined degeneration after intrathecal chemotherapy. Report of two cases]. / Síndrome de degeneración combinada de la médula espinal y radiculopatía en dos pacientes por quimioterapia intratecal con metrotrexato y citarabina. Casos clínicos.

Intrathecal chemotherapy may be complicated with the development of myelopathies or toxic radiculopathies. This myeloradicular involvement, of toxic character, is unpredictable, since these patients have repeatedly received Intrathecal chemotherapy with the same drugs without apparent injury. The toxic effect should be mainly attributed to Cytarabine and not to methotrexate, since the central nervous system lacks Cytidine deaminase, the enzyme that degrades Cytarabine. We report two patients, an 18-year-old woman and a 16 years old male, who received systemic and intrathecal chemotherapy (methotrexate, cytarabine) for the treatment of an acute lymphoblastic leukemia and developed, in relation to this procedure, a spinal subacute combined degeneration. They had a proprioceptive and motor alteration of the lower extremities and neuroimaging showed selective rear and side spinal cord hyper intensity produced by central axonopathy. Two weeks later the woman developed a quadriplegia and the young man a flaccid paraplegia due to added root involvement.

[Sustained upgaze in a patient who ingested high doses of bupropion. Report of one case]. / Supraversión de la mirada en intoxicación mortal por bupropión.

Upgaze or sustained elevation of the eyes, is an alteration of ocular motility initially described in hypoxic coma. We report a 65-year-old woman admitted with hypotension and alteration of sensorium due to the ingestion of 9.5 g of Bupropion. She presented two seizures of short duration, without epileptic activity on the EEG. She had a persistent asynchronous myoclonus in extremities, tachycardia and prolonged Q-t. She suffered a cardiac arrest caused by asystole, which recovered quickly in five minutes. At that moment, upgaze appeared, associated with a persistent ocular opening, which persisted for days, but finally disappeared, without remission of coma. A magnetic resonance imaging done at the eighth day, showed hyperintensity of the oval center and corpus callosum which disappeared in a new imaging study done 30 days later, where images of hypoxia in the basal nuclei and cortex appeared. The patient died forty seven days after admission. Up-gaze is an ominous oculomotor alteration linked to an important but incomplete damage in the cerebral cortex, a condition that perverts some sequences of the ocular opening, reversing the Bell phenomenon and producing eyelid retraction.

Investigación clínica de la ptosis cerebral: presentación de seis nuevos casos / Cerebral ptosis: analysis of six cases

Background: Cerebral ptosis is understood as the bilateral paralysis of eyelid elevation linked to a stroke or hemorrhage of the middle cerebral artery (MCA). It is a transient condition, independent of the evolution of the lesion. Aim: To analyze six patients with the condition. Patients and Methods: Report of five women and one male aged 42 to 72 years. Results: All suffered an infarction or hemorrhage in the territory of the middle cerebral artery of the non-dominant hemisphere and developed a bilateral palpebral ptosis. The recovery started after the fourth day. At the tenth day, eye opening was effortless and did not require frontal help, despite the persistence of hemiplegia. Conclusions: Cerebral ptosis is a mimetic dysfunction of a specific non-injured area of the cerebral cortex, originated from a nearby parenchymal damage such as the middle cerebral artery of the same hemisphere. Cerebral ptosis expresses the inhibition of the voluntary eyelid elevation center, of prefrontal location in the non-dominant hemisphere.

Síndrome de degeneración combinada de la médula espinal y radiculopatía en dos pacientes por quimioterapia intratecal con metrotrexato y citarabina: casos clínicos / Spinal subacute combined degeneration after intrathecal chemotherapy: report of two cases

Intrathecal chemotherapy may be complicated with the development of myelopathies or toxic radiculopathies. This myeloradicular involvement, of toxic character, is unpredictable, since these patients have repeatedly received Intrathecal chemotherapy with the same drugs without apparent injury. The toxic effect should be mainly attributed to Cytarabine and not to methotrexate, since the central nervous system lacks Cytidine deaminase, the enzyme that degrades Cytarabine. We report two patients, an 18-year-old woman and a 16 years old male, who received systemic and intrathecal chemotherapy (methotrexate, cytarabine) for the treatment of an acute lymphoblastic leukemia and developed, in relation to this procedure, a spinal subacute combined degeneration. They had a proprioceptive and motor alteration of the lower extremities and neuroimaging showed selective rear and side spinal cord hyper intensity produced by central axonopathy. Two weeks later the woman developed a quadriplegia and the young man a flaccid paraplegia due to added root involvement.

Supraversión de la mirada en intoxicación mortal por bupropión / Sustained upgaze in a patient who ingested high doses of bupropion: report of one case

Upgaze or sustained elevation of the eyes, is an alteration of ocular motility initially described in hypoxic coma. We report a 65-year-old woman admitted with hypotension and alteration of sensorium due to the ingestion of 9.5 g of Bupropion. She presented two seizures of short duration, without epileptic activity on the EEG. She had a persistent asynchronous myoclonus in extremities, tachycardia and prolonged Q-t. She suffered a cardiac arrest caused by asystole, which recovered quickly in five minutes. At that moment, upgaze appeared, associated with a persistent ocular opening, which persisted for days, but finally disappeared, without remission of coma. A magnetic resonance imaging done at the eighth day, showed hyperintensity of the oval center and corpus callosum which disappeared in a new imaging study done 30 days later, where images of hypoxia in the basal nuclei and cortex appeared. The patient died forty seven days after admission. Up-gaze is an ominous oculomotor alteration linked to an important but incomplete damage in the cerebral cortex, a condition that perverts some sequences of the ocular opening, reversing the Bell phenomenon and producing eyelid retraction.

[Giant cell arteritis of the vertebrobasilar system, posterior ischemia and palsy of the third nerve. Report of one case]. / Arteritis de células gigantes en el sistema vertebrobasilar, isquemias cerebelo-occipitales y parálisis III par. Caso clínico.

Giant cell arteritis is the most common vasculitis in patients aged over 50 years. We report an 89-year-old woman with significant weight loss and persistent frontal-occipital headaches lasting two months. The neurological examination at admission identified a decrease in visual acuity of the left eye, paralysis of the third cranial nerve of the right eye and alterations of body motility without objective signs of damage of the motor or sensitive pathways. Magnetic resonance imaging showed changes of the temporal artery wall and in both vertebral arteries, as well as bilateral cerebellar and occipital ischemic lesions. The Doppler ultrasound of the temporal arteries was compatible with Giant cell arteritis. Treatment with steroids was started. While receiving oral prednisone, the patient suffered new infarcts of the posterior territory, documented with a CAT scan.

[Eyelid retraction of neurologic origin: Report of three cases]. / Retracción palpebral de causa neurológica: Presentación de tres pacientes, interpretación patogénica.

Eyelid retraction, has received limited attention and it has passively been interpreted as the result of an overactive levator palpebrae superioris muscle secondary to midbrain injury. However, eyelid retractions can occur in other neurological diseases, not directly related with the midbrain. We report three patients who developed eyelid retraction. One patient had a bilateral eyelid retraction, related with Creutzfeldt-Jakob disease (CJD). Another patient had a unilateral right eyelid retraction associated with a thalamic-mesencephalic infarct. The third patient had a bilateral pontine infarction on magnetic resonance imaging. In the patient with CJD, eyelid retraction did not subside. Among patients with infarctions, the retraction persisted after focal symptoms had subsided, showing an evolution that was apparently independent of the basic process. The analysis of these patients allows us to conclude that the pathogenesis of eyelid retraction includes supranuclear mechanisms in both the development and maintenance of the phenomenon. Unilateral or bilateral eyelid retraction does not alter the normal function of eyelid, which ever had normal close eye blink. In these reported cases, a hyperactivity of levator palpebrae superioris muscle was clinically ruled out.

Retracción palpebral de causa neurológica: presentación de tres pacientes, interpretación patogénica / Eyelid retraction of neurologic origin: report of three cases

Eyelid retraction, has received limited attention and it has passively been interpreted as the result of an overactive levator palpebrae superioris muscle secondary to midbrain injury. However, eyelid retractions can occur in other neurological diseases, not directly related with the midbrain. We report three patients who developed eyelid retraction. One patient had a bilateral eyelid retraction, related with Creutzfeldt-Jakob disease (CJD). Another patient had a unilateral right eyelid retraction associated with a thalamic-mesencephalic infarct. The third patient had a bilateral pontine infarction on magnetic resonance imaging. In the patient with CJD, eyelid retraction did not subside. Among patients with infarctions, the retraction persisted after focal symptoms had subsided, showing an evolution that was apparently independent of the basic process. The analysis of these patients allows us to conclude that the pathogenesis of eyelid retraction includes supranuclear mechanisms in both the development and maintenance of the phenomenon. Unilateral or bilateral eyelid retraction does not alter the normal function of eyelid, which ever had normal close eye blink. In these reported cases, a hyperactivity of levator palpebrae superioris muscle was clinically ruled out.

[Toxic encephalopathy caused by liquefied gas exposure: Report of one case]. / Encefalopatía tóxica por isopropanol: Sobre-exposición accidental a gas propano.

Liquefied hydrocarbon gas, such as propane is considered safe. However there are reports that voluntary exposure to liquefied gas at least could originate hallucinatory states. We report a 20 years old woman who was found in a coma with extensor muscle hypertonia, brisk tendon reflexes and extensor plantar (Babinski) responses after being exposed to propane gas. The brain magnetic resonance imaging (MRI) showed lesions in both hippocampi and white matter in the oval center. The patient had a normal oxygen saturation of 98%, a carboxyhemoglobin of 1.6% and a metabolic acidosis with a pH of 7.01 with an anion gap of 16 mEq/l. This pattern suggested that it was a consequence of the intermediary metabolism of isopropanol. The recovery of the patient was slow and four months later she still had lesions on MRI and limitations in her cognitive sphere, memory and executive functions. Thus, liquefied gas exposure can cause a toxic encephalopathy with a persistent damage of the central nervous system.

Encefalopatía tóxica por isopropanol: sobre-exposición accidental a gas propano / Toxic encephalopathy caused by liquefied gas exposure: report of one case

Liquefied hydrocarbon gas, such as propane is considered safe. However there are reports that voluntary exposure to liquefied gas at least could originate hallucinatory states. We report a 20 years old woman who was found in a coma with extensor muscle hypertonia, brisk tendon reflexes and extensor plantar (Babinski) responses after being exposed to propane gas. The brain magnetic resonance imaging (MRI) showed lesions in both hippocampi and white matter in the oval center. The patient had a normal oxygen saturation of 98%, a carboxyhemoglobin of 1.6% and a metabolic acidosis with a pH of 7.01 with an anion gap of 16 mEq/l. This pattern suggested that it was a consequence of the intermediary metabolism of isopropanol. The recovery of the patient was slow and four months later she still had lesions on MRI and limitations in her cognitive sphere, memory and executive functions. Thus, liquefied gas exposure can cause a toxic encephalopathy with a persistent damage of the central nervous system.

Leucoencefalopatía tóxica fatal: tres casos asociados al consumo de pasta base de cocaína / Fatal toxic leukoencephalopathy associated with consumption of pasta base of cocaine: Report of three cases

The prevalence of drug-associated toxic encephalopathy is unknown, but it is an uncommon condition. Toxic leukoencephalopathy was described associated with heroin consumption, it has been less commonly described with the use of cocaine and there are no reports of its association with consumption pasta base of cocaine (PBC). We report two females aged 31 years and a male aged 19 years, consumers of PBC who developed a fatal toxic leukoencephalopathy. They initiated their disease with severe and persistent headache, sequential focal neurologic deficits and a progressive impairment of consciousness that culminated with their death. Laboratory parameters such as blood count, cerebrospinal fluid analyses or infectious biological indices were normal. MRI showed multifocal lesions in brain white matter of both hemispheres confirming the leukoencephalopathy. There was no response to the use of methylprednisolone.

[Fatal toxic leukoencephalopathy associated with consumption of pasta base of cocaine: Report of three cases]. / Leucoencefalopatía tóxica fatal: tres casos asociados al consumo de pasta base de cocaína.

The prevalence of drug-associated toxic encephalopathy is unknown, but it is an uncommon condition. Toxic leukoencephalopathy was described associated with heroin consumption, it has been less commonly described with the use of cocaine and there are no reports of its association with consumption pasta base of cocaine (PBC). We report two females aged 31 years and a male aged 19 years, consumers of PBC who developed a fatal toxic leukoencephalopathy. They initiated their disease with severe and persistent headache, sequential focal neurologic deficits and a progressive impairment of consciousness that culminated with their death. Laboratory parameters such as blood count, cerebrospinal fluid analyses or infectious biological indices were normal. MRI showed multifocal lesions in brain white matter of both hemispheres confirming the leukoencephalopathy. There was no response to the use of methylprednisolone.

Síndrome de meningitis y retención urinaria / Meningitis-retention syndrome. Report of one case

The Meningitis-Retention Syndrome associates aseptic meningitis and neurogenic bladder, with a vesical dysfunction that outlasts meningitis widely. Urodynamic assessment shows a detrusor palsy with normal function of the external sphincter. We report a 24-year-old male admitted for headache, fever, myalgias and acute urinary retention, which was diagnosed as a urinary tract infection. Worsening of symptoms and slight meningeal signs prompted for a lumbar puncture that yielded a cerebrospinal fluid with 94 lymphocytes, in which etiological evaluation was inconclusive. Meningeal syndrome and myalgia subsided by the fifth day, while urinary retention persisted. A magnetic resonance imaging of the brain and spinal cord done at the fifth day, showed high intensity signals in basal ganglia and central spinal cord, not altered by contrast. These images disappeared in the imaging control performed two months later. Bladder dysfunction lasted at least until the second month of follow up.

Nocardiosis cerebral parvosintomática, en pacientes inmunocomprometidos / Parvosymptomatic cerebral nocardiosis in immunocompromised patients

Antecedentes: La nocardiosis es originada por distintas cepas de Nocardia, bacterias Gram positivas que afecta a humanos y animales. Pueden producir infecciones sistémicas de ingreso cutáneo o pulmonar, que llegan a comprometer el Sistema Nervioso Central. Se afectan especialmente pacientes inmunosuprimidos que pueden desarrollar abscesos cerebrales, visibles en la Resonancia Magnética (RM), pero que no expresan síntomas de las lesiones focales o son parvosintomáticos. Pacientes y Método: Queremos comunicar dos mujeres con trasplante renal en tratamiento inmunosupresor, que desarrollaron cuadros pulmonares agudos que obligaron a su hospitalización, en cuyo contexto la paciente (A) presentó una convulsión y la (B) cefalea y compromiso de conciencia, que obligaron a una RM de cerebro. En ambos casos se encontraron múltiples abscesos cerebrales de distinta ubicación y tamaño que no habían dado síntomas focales. La nocardiosis se identificó en la paciente (A) con la biopsia de un micetoma cutáneo y en la (B) con la resolución quirúrgica de un absceso cerebeloso. En ambas se inició tratamiento específico con adecuada respuesta. Sin embargo, las reacciones adversas a la antibioterapia obligaron a suspenderla. Esta suspensión reactivó la infección que complicó y llevó al fallecimiento de las pacientes. Conclusiones: La publicación de varios casos de nocardiosis cerebral parvosintomática en pacientes inmunosuprimidos sugiere que para las infecciones cerebrales por Nocardia la pérdida de la inmunidad celular resulta muy significativa, porque permitiría el ingreso y proliferación de la bacteria al interior del SNC sin generar respuestas clínicas inmediatas. La aparición de síntomas se relacionaría con una tardía alteración de la barrera hematoencefálica, más que con el lento proceso lesional de la Nocardia. Lo que condicionaría su diagnóstico oportuno.

Background: Nocardiosis is caused by several strains of Nocardia, Gram-positive bacteria that infects humans and animals likewise. They develop a systemic infection of pulmonary or cutaneous origin that can spread to the Central Nervous System. It frequently affects immunosupresed patients, in which parvosymptomatic cerebral abscess has been described, visible in magnetic resonance imaging but without focal symptoms. Patients and Methods: We want to communicate two women with renal transplant in immunosupresor treatment who were admitted to our hospital for acute pulmonar disease, during which patient A presented a convulsive episode and patient B headache and stupor, after which CT and MR were obtained. In both cases multiple cerebral abscesses were found, of different sizes and location, with no clinical manifestations. Nocardia diagnosis was made in patient A by biopsy from a cutaneous mycetoma and in patient B after surgery of a cerebellar abscess. In both cases antimicrobial treatment was initiated with good response, but had to be interrupted due to adverse effects. This reactivated the infection, which had a complicated course and finally lead to the death of both patients. Conclusions: The fact that several cases of parvosymtomatic cerebral Nocardiosis in immunosupresed patients have been published suggest that cellular immunosupresion is key in the development of cerebral infections by Nocardia. It probably allows the access and multiplication of the bacteria inside the encephalon without an immediate clinical response. The development of symptoms is probably related to a late alteration of the blood-brain barrier rather than to the slow progression of Nocardia disease.

Encefalitis autoinmune reversible y anticuerpos anti-receptores de N-metil-D-aspartato: Report of one case / Limbic encephalitis with positive anti-N-methyl-D-aspartate antibodies

Background: Limbic encephalitis is a subacute syndrome characterized by memory impairment, confusion, seizures, hypothalamic dysfunction and psychiatric symptoms. It has been associated to tumors located outside of the central nervous system. In 2007, anti-N-methyl-D-aspartate receptors (NMDAr) antibodies were found in serum and CSF of patients with this particular type of encephalitis. We report a 25-year-old female who, following upper respiratory tract symptoms, developed serious behavioral and consciousness impairment that progressed to coma. Cerebrospinal fluid (CSF) analysis showed a lymphocyte pleocytosis, the electroencephalogram was altered with a slow encephalopathic rhythm and a brain magnetic resonance imaging was normal. Infectious etiologies were ruled out. CSF and serum anti NMDA receptors antibodies were positive.

Estatus parcial continuo, causa de hiperintensidad de la corteza cerebral en la resonancia nuclear magnética / Continous partial status cause of hyperintensity in cerebral cortex in magnetic resonance imaging

Magnetic Resonance Imaging has demonstrated functional changes of the cerebral cortex in relation to status epilepticus, which can eventually localize the origin of the crisis. The purpose of this presentation is relevant to this condition and pretends to highlight the action of incidental situations that can modify it. We present a 29 year old woman with a neurosurgical intervention for a neuroblastoma irradiated fifteen years ago, which incidentally starts a continuous partial status epilepticus, expressed by clonies of the face and left limbs associated with functional impotence, resistant to oral therapy. Faced with the suspicion of recurrence of the tumor, a brain MRI is performed, showing hyperintensity of all neural areas the right hemisphere, with no evidence of tumor recurrence. Once submitted the status epilepticus, the hyperintensity disappeared in the hemisphere. This extensive reaction of the neural structures might be related to a permanent effect of radiation, which may have caused a mismatch functional glia, of the blood-brain barrier and interneural network.

La Resonancia Nuclear Magnética (RM) ha puesto en evidencia cambios funcionales de la corteza cerebral en relación a estados epilépticos que eventualmente permiten localizar el origen de las crisis. El propósito de esta presentación es hacer relevante dicha condición y destacar la acción de situaciones incidentales que pueden modificarla. Se presenta a una mujer de 29 años portadora de una intervención neuroquirúrgica por un neuroblastoma irradiado hace quince años, que incidentalmente inicia un estatus epiléptico parcial continuo, expresado por clonías de la cara y extremidades izquierdas asociadas a impotencia funcional resistente a la terapia oral. Frente a la sospecha de recidiva de la neoplasia se realiza RM cerebral que muestra una hiperintensidad de todas las áreas neuronales del hemisferio derecho, sin evidencias de recidiva tumoral. Una vez remitido el estado epiléptico se observó una desaparición de estas alteraciones. La interpretación para esta extensa reacción de las estructuras neurales podría estar relacionado con un efecto permanente de la irradiación, que pudo haber provocado un desajuste funcional de la glía, de la barrera hematoencefálica y de la red interneural.