[Focal neuropsychological deterioration by posterior lobar atrophy (posterior cortical dementia)]. / Deterioro neuropsicológico focal por atrofia lobar posterior (demencia cortical posterior). Correlación clinicorradiológica.

A right-handed 59 year old man who presented difficulties in the performance of complex acts (praxic) and spatial disorientation is described. Neurophysical exploration showed deterioration of the capacities linked to perceptive and spatial organization preserving the verbal capacities including the memory. After two years and a half of follow up practically no variation has been observed in his clinical manifestations with no implication of other superior mental function. CAT and MR findings revealed important posterior atrophy with an increase in the occipital loops. SPECT demonstrated cold images due to a bilateral parietal-temporal perfusion deficit. Discussion of the case leads to the needs of unifying the criteria and terminology for these focal degenerative processes.

[Paraganglioma of the cauda equina]. / Paraganglioma de la cauda equina.

The case of a 36 year old woman with a paraganglioma of the cauda equina was studied. This localization is rare and special emphasis is made concerning the peculiarities of presentation, aggravating factors of the clinical manifestations and neuroradiologic findings. A review of the 66 paragangliomas of the cauda equina published to date is carried out. This entity deals with a tumor in the adult, with slight male predominance and a clinical presentation not differing from that of other lesions occupying the space of the cauda equina. The most frequent initial symptom is low back pain with or without sciatic irradiation. Total resection of the tumor may cure the patient.

[Amyotrophic lateral sclerosis syndrome and hyperthyroidism. Cure with antithyroid drugs]. / Syndrome de sclérose latérale amyotrophique et hyperthyroïdie. Guérison sous antithyroïdiens.

We report the case of a 62-year old man presenting with generalized muscular weakness, amyotrophy, dysarthria and dysphagia. Neurological examination showed bilateral pyramidal signs and lingual fasciculations. The clinical diagnosis was amyotrophic lateral sclerosis, since only shivers and weight loss pointed to hyperthyroidism. However, after several months the patient developed typical manifestations of hyperthyroidism. After treatment of hyperthyroidism, the neurological symptoms disappeared. Although this association is extremely rare, one must have in mind the possibility of thyroid dysfunction when studying patients with amyotrophic lateral sclerosis.

Hydrocephalus in neurofibromatosis. Contribution of magnetic resonance imaging to its diagnosis, control and treatment.

Cerebral ventricular dilation and/or frank hydrocephalus unrelated to brain tumors is not a rare feature of von Recklinghausen neurofibromatosis (NF-1). In our experience, it was observed in 23% of patients consulting for neurological problems. From 1984 to 1989, 30 patients with documented NF-1 were referred to for cranial or spinal magnetic resonance imaging (MRI). In 9 of these patients, clinical features or previous computed tomographic scanning revealed hydrocephalus or ventriculomegaly. One patient had biventricular hydrocephalus (enlarged lateral ventricles), 7 had triventricular hydrocephalus (aqueductal stenosis) and 1 had tetraventricular hydrocephalus (obstruction of the foramina of Magendie and Luschka). MRI showed anomalies in all 9 patients. The importance of MRI for the diagnosis, control and treatment of the hydrocephalus as well as for understanding the embryologic pathogenesis of these conditions is emphasized.

Optic pathway gliomas in neurofibromatosis.

Two patients, a 5-year-old girl and a 3-year-old boy, with documented neurofibromatosis (NF-1) and visual pathway gliomas are reported. In the first patient, the tumor was a typical pilocytic astrocytoma confined to the proximal half of the right optic nerve just near the globe. The tumor was excised; after a follow-up of 7 years recurrence has not occurred. The second patient had a glioma of the left optic nerve, with involvement of the chiasm, optic tracts, probably lateral geniculate body, optic radiations and basal ganglia. Biventricular hydrocephalus, possibly due to the occlusion of Monro's foramina, was also noted. In this case, magnetic resonance imaging (MRI) was superior to computed tomography for visualizing the posterior extension of the lesions. The patient received X-ray therapy and after a follow-up of 3 years the clinical symptomatology remains stationary. It is suggested that the optic pathway involvement detected by MRI may represent a dysplastic element NF-1 rather than a truly neoplastic change.