Posterior fossa syndrome after posterior fossa surgery in children with brain tumors

BACKGROUND

Posterior fossa syndrome (PFS) is defined as the temporary and complete loss of speech after posterior fossa surgery. The goal of this study was to identify incidence and risk factors for PFS and to determine accompanying neurobehavioral and psychologic problems.

PROCEDURE

Between May 2007 and April 2009, children with brain tumors having posterior fossa surgery were evaluated neurologically and psychologically in preoperative and postoperative period.

RESULTS

PFS developed in 9 patients among 36 (25%) included in the study. Mutism continued for 120 days in one patient. Histopathological diagnosis (P = 0.05), location of the tumor (P = 0.05) and socioeconomic level of the family (P = 0.06) gave the significant results in relation with the PFS by univariate analyses. In multivariate analysis the risk of developing PFS was found 7.2 times higher in patients with medulloblastoma, 6.7 times higher in tumors located at the midline, 5.7 times higher in families with low socioecnomic level. Intelligence quotients of the patients in PFS and other group (P = 0.85) with Wechsler Intelligence Scale for Children and the results of the Denver II Developmental Screening Test were not significant statistically (P = 0.5).

CONCLUSION

The diagnosis of medulloblastoma, midline location of the tumor and low socioeconomic level of the families are important risk factors for the development of PFS. These findings support the hypothesis that temporary ischemia and edema due to retracted and manipulated dentate nuclei and superior cerebellar pedincles may be the cause of mutism.

[Vascular aphasias: clinical, epidemiologicaland evolutionary aspects]

INTRODUCTION

Aphasias constitute an acquired disorder of the language. Aetiologies are dominated by stroke. The aim of this study was to describe the clinical, epidemiological and evolutionary aspects of the vascular aphasias.

MATERIALS AND METHODS

We conducted from August 2003 to May 2005 a descriptive cross-sectional study at the Neurology department in Dakar. This study concerned all patients admitted at the Neurology department for stroke confirmed by the cerebral tom densitometry. All patients were subjected to an examination of the language allowing to confirm the diagnosis of aphasia and to determine the type. The follow-up was monthly during one year.

RESULTS

55 cases of aphasia were reported on 170 cases of stroke (frequency: 32.35%). Our patients were all right-handed. Mean age was 56.8 (28 to 86 years) with a sex-ratio of 0.61.76.36% of the patients could neither read nor to write. Only two made higher studies. The nature of stroke was ischemic in 73.7% and hemorrhagic in 26.3%. The aphasias with expressive language impairment were observed in 96.4% against 3.6% of the cases for aphasias with comprehensive language impairment. After one year of evolution, a regression of the disorders was observed only in 9 cases, and the regression was partial in 25 cases. The evolution of the aphasia was correlated with that of the motor deficit. Age, low educational level, ischemic stroke constitute factors of bad prognosis.

CONCLUSION

Vascular aphasias are frequent and of reserved prognosis. It disturbs social professional and family reintegration.

Nasal consonant production in Broca's and Wernicke's aphasics: speech deficits and neuroanatomical correlates

The present study investigated the articulatory implementation deficits of Broca's and Wernicke's aphasics and their potential neuroanatomical correlates. Five Broca's aphasics, two Wernicke's aphasics, and four age-matched normal speakers produced consonant-vowel-(consonant) real word tokens consisting of [m, n] followed by [i, e, a, o, u]. Three acoustic measures were analyzed corresponding to different properties of articulatory implementation: murmur duration (a measure of timing), amplitude of the first harmonic at consonantal release (a measure of articulatory coordination), and murmur amplitude over time (a measure of laryngeal control). Results showed that Broca's aphasics displayed impairments in all of these parameters, whereas Wernicke's aphasics only exhibited greater variability in the production of two of the parameters. The lesion extent data showed that damage in either Broca's area or the insula cortex was not predictive of the severity of the speech output impairment. Instead, lesions in the upper and lower motor face areas and the supplementary motor area resulted in the most severe implementation impairments. For the Wernicke's aphasics, the posterior areas (superior marginal gyrus, parietal, and sensory) appear to be involved in the retrieval and encoding of lexical forms for speech production, resulting in increased variability in speech production.

Semantic weight and verb retrieval in aphasia

Individuals with agrammatic aphasia may have difficulty with verb production in comparison to nouns. Additionally, they may have greater difficulty producing verbs that have fewer semantic components (i.e., are semantically "light") compared to verbs that have greater semantic weight. A connectionist verb-production model proposed by Gordon and Dell (2003) learns through error correction to "divide the labor" between syntax and semantics. Verbs that are semantically heavier come to depend less on syntax and more on semantics. For lighter verbs, the reverse is true. We performed this study to clarify the role of semantic weight in aphasic verb production and to test the prediction from Gordon and Dell that a brain lesion that impairs the syntactic input to verb retrieval will impair lighter verbs more than heavier ones. Consistent with this prediction, we found that the decrement for lighter verbs was present in a group with agrammatic aphasia but not in a matched group without agrammatism.

Effect of lexical cues on the production of active and passive sentences in Broca's and Wernicke's aphasia

This study compared the sentence production abilities of individuals with Broca's and Wernicke's aphasia in an attempt to explore the extent to which impaired lexical retrieval impedes sentence production. The ability to produce active and passive reversible and non-reversible sentences was examined when varying amounts of lexical information was provided. The results showed that both Wernicke's and Broca's aphasic individuals were impaired in passive sentence production and that these difficulties were not overcome when lexical cues (the relevant nouns and uninflected verb) were provided. However when auxiliary and past tense morphemes were provided along with the verb stem, production of passive sentences improved drastically for both groups. Analysis of error patterns, however, revealed differences between the two groups, suggesting that Broca's aphasic subjects may find passive sentences difficult due to problems with retrieving the relevant grammatical morphemes. Subjects with Wernicke's aphasia may have been unable to automatically access the passive sentence structure.

Stroke-related aphasias mistaken for psychotic speech: two case reports

A large portion of the human central nervous system is dedicated to and specialized for language function. Aphasias, disorders of language, can be seen in many psychiatric and neurologic conditions. On occasion, it is difficult to differentiate between language abnormalities secondary to a patient's psychiatric illness and those secondary to a superimposed neurologic condition. In particular, in the evaluation of a patient with a history of a psychotic illness, it is easy to misinterpret the presentation of "abnormal" speech as an exacerbation of the patient's pre-existing psychiatric illness. To show this psychoneurologic comorbidity, two case reports are presented.

Melodic intonation in the rehabilitation of Romanian aphasics with bucco-lingual apraxia

The main objective of the present study was to assess the efficiency of the melodic intonation therapy (MIT) in the rehabilitation of Romanian aphasics. Eighty predominantly Broca aphasics used the melodic intonation therapy when no other therapy methods were very efficient. The speech therapist intonated the respective word, then together with the patient and finally let him continue alone. The control group counted 80 aphasics and it applied other therapy methods. Each patient, regardless of the group, was tested twice, before and after therapy. Since most of the patients displayed severe language disorders, and other therapy methods failed in rehabilitating them, MIT was considered an efficient method in the early stages of Broca aphasia with bucco-lingual apraxia.

Influence of age, sex, literacy and pathologic lesion on incidence, severity and type of aphasia

The influence of sex, age, educational level and pathologic lesion on incidence, severity and clinical form of aphasia was investigated in 390 right-handed, left brain-damaged patients. Sex and educational level were not related to any parameter. Etiology of lesion and age were related to both incidence and type of aphasia. Incidence of aphasia increased with age and was higher in patients with cerebrovascular accidents than in subjects with other types of brain lesions. Non-fluent forms of aphasia were more frequent in young patients suffering from acute cerebrovascular accidents, whereas anomia prevailed in neoplastic subjects and Wernicke's aphasia increased regularly in frequency with age. Some tentative explanations of these findings are discussed.

The influence of sex and age on the incidence and type of aphasia

The relation of sex and age to the incidence and type of aphasia was investigated in 200 aphasic patients. The following conclusions were drawn: (1) Males and females show language disorder with equal frequency. (2) There is a prevalence of non-fluent aphasics in males as compared to females. (3) Broca's aphasics are mildly, but significantly young than Wernicke's aphasics.