Neurografía por resonancia magnética de alta resolución (3Tesla) del nervio ciático / High resolution (3T) magnetic resonance neurography of the sciatic nerve

La neurografía por resonancia magnética (RM) hace referencia a un conjunto de técnicas con capacidad para valorar óptimamente la estructura de los nervios periféricos y de los plexos nerviosos. Las nuevas secuencias neurográficas 2D y 3D, en particular en equipos de 3 Tesla, consiguen un contraste excelente entre el nervio y las estructuras perineurales. La neurografía por RM permite distinguir el patrón fascicular normal del nervio y diferenciarlo de las anomalías que lo afectan, como inflamaciones, traumas y tumores. En este artículo se describe la estructura del nervio ciático, sus características en la neurografía por RM y las dolencias que lo afectan con mayor frecuencia (AU)

Magnetic resonance (MR) neurography refers to a set of techniques that enable the structure of the peripheral nerves and nerve plexuses to be evaluated optimally. New two-dimensional and three-dimensional neurographic sequences, in particular in 3T scanners, achieve excellent contrast between the nerve and perineural structures. MR neurography makes it possible to distinguish between the normal fascicular pattern of the nerve and anomalies like inflammation, trauma, and tumor that can affect nerves. In this article, we describe the structure of the sciatic nerve, its characteristics on MR neurography, and the most common diseases that affect it (AU)

[High resolution (3 T) magnetic resonance neurography of the sciatic nerve]. / Neurografía por resonancia magnética de alta resolución (3 Tesla) del nervio ciático.

Magnetic resonance (MR) neurography refers to a set of techniques that enable the structure of the peripheral nerves and nerve plexuses to be evaluated optimally. New two-dimensional and three-dimensional neurographic sequences, in particular in 3T scanners, achieve excellent contrast between the nerve and perineural structures. MR neurography makes it possible to distinguish between the normal fascicular pattern of the nerve and anomalies like inflammation, trauma, and tumor that can affect nerves. In this article, we describe the structure of the sciatic nerve, its characteristics on MR neurography, and the most common diseases that affect it.

[Characterization of a group of patients with cryptococcosis of the central nervous system]. / Caracterizacion de un grupo de pacientes con criptococosis del sistema nervioso central.

INTRODUCTION: Incidence of cryptococcosis of the central nervous system has risen sharply since AIDS became pandemic; from early 1998, the Instituto de Neurología y Neurocirugía in Havana has beaten its own record in the number of cases attended. AIM: To describe the clinical epidemiological characteristics of patients with this disease who were hospitalised in this centre between 1991 and 2000. PATIENTS AND METHODS: We present a descriptive study of 16 adult individuals who were admitted for this reason. Data on variables related with aspects concerning their epidemiology, clinical features, treatment and evolution were collected from a review of the clinical records and a survey conducted by post. RESULTS: It was found that in no cases did the disease appear as an epidemic outbreak, in 75% of the patients there was some kind of link with pigeons, none of the patients were HIV positive, and 50% displayed other causes of immunosuppression. Clinical behaviour varied and forms of meningitis and meningoencephalitis were prevalent; 37.5% of the patients displayed mild forms of the disease and 62.5% had more serious forms. The initial symptom in most cases was headache. The most constant CSF pattern was a raised protein level in the cerebrospinal fluid with scarce cellularity. 87.5% of the patients were cured of the disease by treatment involving amphotericin B, in some cases associated with fluconazole. Death and the presence of post treatment sequelae were observed in patients with serious clinical forms and late diagnoses

[Cryptococcosis of the central nervous system. A report of five cases]. / Criptococosis del sistema nervioso central. A propósito de cinco casos.

INTRODUCTION: Since the 1980s, in relation to the spread of AIDS, there has been an enormous increase in cryptococcosis, a mycotic disorder which usually affects the central nervous system (CNS). This disease is caused by Cryptococcus neoformans, a microorganism acquired by inhalation of bird excrement. This germ produces a capsule which protects it from phagocytosis, can synthesize melanin which acts as an antioxidant of the cytotoxic lymphocytes and can reproduce at body temperature. Clinically it may show as chronic or subacute meningitis and/or encephalitis, as endocranial hypertension or as an intracranial space occupying lesion (crytococcoma). To establish the diagnosis, Chinese ink, culture and the latex agglutination test are useful. Treatment is with amphotericin B associated or not with fluocytokine and fluconazole, the protocol used depending on the clinical form. OBJECTIVE: To review the most up-to-date literature on cryptococcosis of the CNS to study the condition in relation to five cases. CLINICAL CASES: We report five patients with cryptococcosis of the CNS diagnosed and treated in the Instituto Nacional de Neurología y Neurocirugia de la Habana, Cuba, showing an increase in the frequency of the occurrence of cases not related to HIV infection, great variety of clinico-humoral presentation and the characteristics of the treatment given. CONCLUSION: Cryptococcosis can be cured completely when the condition is diagnosed early; without treatment it is invariably fatal.

[Assessment of neurotoxic effects of methyl bromide in exposed workers]. / Estudio de los efectos neurotóxicos del bromuro de metilo sobre trabajadores expuestos.

BACKGROUND: Methyl bromide is an aliphatic hydrocarbon derivative used as a pesticide that causes skin, kidney, respiratory, liver and neurological damage. AIM: To assess the neurological and psychiatric damage caused by methyl bromide in exposed workers of seed and fruit export industries in a rural area near Santiago. SUBJECTS AND METHODS: We studied prospectively 15 male middle age workers before and after a fumigation period with methyl bromide, that lasted two to four weeks. According to the initial assessment, 5 of these subjects had a chronic exposure to the chemical. As controls, 10 non exposed workers matched for age, sex and working conditions were studied in two occasions. The evaluation included the WHO Neuro Behavior Core Test Battery, dynamometric and vibrator assessment of peripheral nerve function, the Nothingham test for psychological functioning and Titmus test for visual acuity. Methyl bromide levels were measured in blood and urine. RESULTS: Blood methyl bromide levels increased from 13.3 to 30 mg/dl after exposure. Symptoms that appeared with a higher frequency in exposed workers were insomnia, headache, paresthesiae, mood changes and loss of memory and concentration. In these subjects, the threshold for the Vibraton test increased from 2.4 to 2.85 sec, dynamometry showed a strength reduction in the right side from 51.4 to 47.2 kg and there was an increase in the score for negative auto-perception in the Nothingham test from 11.2 to 13.6. No deterioration in these tests were observed in unexposed workers. CONCLUSIONS: Acute and chronic methyl bromide exposure causes important psychological and neurological derangement.