Right hemifield alexia without hemianopia.

We studied a 54-year-old man who suffered a stroke in the visual-association areas of the left hemisphere. He showed no right-sided visual field defect and results of a neuropsychologic examination were normal except for his performance in several tasks presented to the right visual field. Naming of drawings was normal in both hemifields but reading of letters, words, digits, and arithmetic symbols was defective in the right field. We believe that the lesion in the visual association areas of the left hemisphere that did not interrupt interhemispheric connections disconnected the primary visual areas from temporoparietal areas of the left hemisphere, affecting reading.

Brain specialization for language does not depend on literacy.

Aphasia in focal brain-damaged illiterates is analogous to aphasia in patients who have learned how to read and write, regarding (1) expectancy rate, (2) distribution of clinical types, (3) semiological structure, and (4) score of relevant laboratory variables. The organization of neurological structures whose lesions produce language disturbances seems to be independent from the acquisition of reading and writing skills.

Transient and persistent right ear extinction in dichotic listening: subcortical lesions.

Nine patients with aphasia had right ear extinction in dichotic listening to words in the first month after an ischemic stroke; they were reassessed after 3 months. Four showed complete recovery from the right ear extinction; in five, the abnormality persisted. In those who recovered, CT revealed a subcortical lesion lateral to the frontal horn of the lateral ventricle without a lesion of Heschl's gyrus or geniculo-temporal pathways; a lesion in those structures was found in patients who did not recover. As reported for subcortical aphasia, a subcortical mechanism may explain contralateral ear extinction in dichotic listening.

Partial section of the corpus callosum: focal signs and their recovery.

A 30-year-old woman underwent surgical partial callosotomy (posterior half) for removal of an arteriovenous malformation. The patient submitted to neuropsychological evaluation before and after surgery for a period of 8 months. There was transient dysfunction attributable to disconnection of parietal, temporal, and occipital connections. Because the symptoms disappeared over time, we conclude that the transcallosal surgical approach can, in the long term, be considered a relatively harmless method.

The response of "de novo" Parkinson's disease patients to bromocriptine in a "low and slow" regimen is predictive for prognosis.

It is possible that Bromocriptine only determines a complete antiparkinson effect in a subset of P.D. patients that have a good dopaminergic reserve. Our study intent to demonstrate that a good short-term response to Bromocriptine used in a "low and slow" regimen is a marker of long term good prognosis. We studied a series of 36 sequential "de novo" P.D. patients treated with Bromocriptine in a "low and slow" regimen. The principal end-point was the introduction of Levodopa. "Good prognosis" was defined as no need of Levodopa until five years of follow-up. An improvement greater than 33% in the Columbia rating scale, at the 6th month of treatment, was the cut-off point to decide that a patient had a good short term response to Bromocriptine. Nine patients fulfilled the criteria for being good short term responders. Multiple regression analysis showed that this outcome could not be predicted by the clinical characteristics of the patients at admission. The sensitivity and the specificity of the short term response to Bromocriptine to predict a good prognosis were 70% and 90.5% respectively. We conclude that Bromocriptine in monotherapy is an efficient antiparkinson agent in 1/3 of "de novo" P.D. patients and good short term response to Bromocriptine is an acceptable marker for a good prognosis. Therefore it is possible that the response to Bromocriptine is a discriminator for a subset of P.D. patients in the early phases of the disease.

Age and type of crossed aphasia in dextrals due to stroke.

Thirty-nine cases (37 from the literature and 2 personal) of crossed aphasia in dextrals due to stroke were reviewed concerning age, sex, and type of aphasia. Results showed that Broca's aphasics are younger than the remaining group, males predominate, and several types of aphasia have been described similarly to the aphasias due to left-hemisphere lesions in dextrals.

Aphasia following right hemisphere lesion in a woman with left hemisphere injury in childhood.

The case of a 56-year-old woman who became aphasic following a right temporoparietal lesion is reported. At the age of 2, this woman had an acute infantile hemiplegia on the right side of the body and it was reported by relatives that a deterioration of language was also noted. There was a slow recovery of these deficits and she was considered as having normal language only at age 7. Although it is difficult to be sure about the hand preference of the patient before the stroke at age 2, the relatives were quite positive saying, that she previously preferred the right hand and that she became left handed. The CT scan showed an old left frontal ischemic lesion and a recent right temporoparietal lesion. This case illustrates the ability of the right hemisphere to take over functions of the left when a left lesion occurs in early stages of language acquisition. Although this is an accepted model for recovery, this is the only case in the literature with a documented early focal lesion of the left hemisphere. Other evidence comes from studies performed in populations where severe epilepsy may contribute to particular functional organization.

Central nervous system vasculitis associated with hepatitis C virus infection: a brain MRI-supported diagnosis.

BACKGROUND: The Hepatitis C virus (HCV) infection is associated with various extrahepatic manifestations, being the Central Nervous System (CNS) rarely involved. CASE REPORT: We report a case of a 54 year-old black man with arterial hypertension who presented with progressively worsening headaches, apathy, somnolence and left hemiparesis. Brain MRI showed an acute ischemic lesion in the left anterior cerebral artery (ACA) and an old ischemic infarct in the right ACA territory. Brain MRI with gadolinium revealed mural thickening and contrast enhancement of the A1 and A2 segments of the ACAs, of the middle and distal basilar artery and of the P1 segment of the left posterior cerebral artery, suggesting active vasculitis. Digital angiography confirmed those irregularities and stenosis. Laboratory evaluation revealed ESR (73 mm/h), transaminase elevation, elevated HCV viral load genotype 2, positive IGRA, negative cryoglobulins, CSF protein elevation with oligoclonal bands (mirror pattern) and no pleocytosis; investigation excluded other infectious causes. Pegylated interferon alpha-2a and ribavirin, corticotherapy and tuberculosis prophylaxis were started with clinical and imagiological improvement. CONCLUSION: The typical inflammation signs of the vascular wall demonstrated by the gadolinium-enhanced MRI strengthened the hypothesis of CNS vasculitis. The association with HCV infection is rare but should be investigated once specific therapeutic is required.