Dysfunkcje wykonawcze w praktyce neurologicznej

Dysfunkcje wykonawcze spotykane w neurologii obejmują liczne i behawioralnie zróżnicowane objawy utraty umiejętności programowania i kontrolowania własnych poczynań, składających się na aktywność sprawczą, czyli działanie. W niniejszej pracy podjęto próbę przedstawienia i skomentowania kilku zagadnień szczegółowych, takich jak: kliniczna heterogeniczność objawów dysfunkcji wykonawczych u osób dorosłych, etiopatogenetyczne i neuroobrazowe korelaty dysfunkcji wykonawczych spotykanych w praktyce neurologicznej, diagnostyczno-metodologiczne aspekty badań (dys)funkcji wykonawczych oraz pomoc (neuro)psychologiczna osobom z problemami wykonawczymi. W artykule podkreślono też walory „ekologicznie” trafnej oceny funkcjonowania pacjentów z deficytem mózgowym, których codzienne problemy często nie przypominają objawów stwierdzonych za pomocą standardowych testów czy wyrafinowanych technik eksperymentalnych

Neuropsychologia jesieni życia

Neuropsychology of later lifeng Contemporary debate on human aging is intensive and multifaceted in nature because of agerelated transformation in many contemporary societies, i.e. a rapid increase of mean life expectancy (increasing numbers of healthy old people). The aim of this article is to discuss changes in brain and behavior that occur in later life. Life-span developmental neuropsychology emphasizes a close relationship between cognitive problems in later life and age-related loss of large neurons in some parts of the brain. Large neurons shrink into smaller neuron classes. The most pronounced atrophic changes have been reported in the prefrontal area, hippocampus, ubstantianigra and locus cinereus. This article presents also common clinical conditions of later life, such as differential diagnosis of age-associated behavioral changes and dementias. There may be multiple causes of neurogeriatric disorders, such as Alzheimer’s disease. There has been considerable interest in the possible causative role of cognitive and brain reserve which differs among individuals. Therefore between-individual heterogeneity related to normal cognitive aging is signifi cant. Namely, if cerebral pathology occurs (e.g., neurodegeneration with dementia), persons with a greater reserve may not demonstrate the same cognitive impact as others with the same pathology (e.g. lesion size) but less reserve. It is also widely believed that mental difficulties in lder adults cannot be easily attributed to psychomotor slowness which may reflect a loss of white matter tissue, i.e. dysmielinisation of nerve fibers. This article emphasizes an importance of ecologically valid assessment of older adults, whose everyday activities and real--world abilities cannot be predicted by the traditional tests and sophisticated procedures emerging from purely experimental investigations

Zaburzenia językowe oraz mowy w praktyce ogólnolekarskiej

Artykuł omawia zaburzenia komunikacji językowej oraz problemy artykulacyjne spotykane w praktyce ogólnolekarskiej. Scharakteryzowano: (a) objawy i podłoże neuroanatomiczne poszczególnych zespołów afazji w ujęciu klasycznym i współczesnym, (b) problemy językowe po uszkodzeniu półkuli podległej mózgu (prawej), (c) zaburzenia językowe w wybranych zespołach otępiennych, oraz (d) niektóre rodzaje dyzartrii. Forum Medycyny Rodzinnej 2008, tom 2, nr 1, 14-2

Cerebral blood flow SPECT imaging in right hemisphere-damaged patients with hemispatial neglect. A pilot study

BACKGROUND: Hemispatial neglect is characterised as a failure by a brain-damaged patient to attend to contralesional space. It is hypothesised to be a result of damage to a network involving the frontal, parietal and cingulated cortices, basal ganglia and thalamus. MATERIAL AND METHODS: The aim of this preliminary study was to verify this model of neglect in 22 right hemisphere-damaged acute stroke patients, using single photon emission-computed tomography (SPECT). The presence of a single rightsided vascular brain lesion was confirmed on CT and/or MRI. Hemispatial neglect, assessed with a battery of drawings, line bisection and line and shape cancellation tests, was observed in 12 cases. RESULTS: Patients with neglect (compared with those without neglect) had more extensive hypoperfusion in the frontal and parietal cortex, as well as striatum and thalamus. Left-sided hypoperfusion in the parietal cortex and the thalamus was also significantly associated with neglect on SPECT imaging. Performance in three out of five psychological tasks commonly used to detect the presence of hemispatial neglect, such as drawing tests and line bisection test, was exclusively linked with damage to the parietal cortex of the right hemisphere, while the line cancellation test might be attributable to the lesion of the right striatum. CONCLUSIONS: These findings support the model attributing hemispatial neglect to a unilateral defect in a cortico-striatothalamo-cortical loop. CBF SPECT imaging may provide a reliable description of the brain pathology associated with hemispatial neglect

Single-photon emission computed tomography in the assessment of cerebral blood flow abnormalities in selected syndromes of aphasia

Wstęp. Wiele różnych zespołów afazji nabytej przypisuje się względnie specyficznym uszkodzeniom odrębnych okolic lewej półkuli mózgu. Celem badań było określenie neuroanatomicznych korelatów afazji po udarze niedokrwiennym mózgu. Materiał i metody. W badaniu wzięło udział 30 pacjentów po ogniskowym udarze lewostronnym mózgu, przejawiających afazję o zróżnicowanym nasileniu, wahającej się od zaburzeń lekkich do głębokich. Stosując Bostoński Test do Diagnozy Afazji, wykazano kilka profilów zaburzeń językowych. Ocenę przepływu mózgowego wykonano za pomocą tomografii emisyjnej pojedynczego fotonu (SPECT) po dożylnym podaniu znacznika 99mTc ECD o aktywności 20 mCi (740 MBq). Trójgłowicowa gamma kamera była wyposażona w specjalny kolimator o wysokiej rozdzielczości do badań neurologicznych. Przeanalizowano różnice regionalnej perfuzji mózgowej u pacjentów z wybranymi rodzajami afazji. Wyniki. Najbardziej widoczne zmiany mózgowego przepływu w afazji ekspresyjnej, określane za pomocą wskaźnika asymetrii, stwierdzono w płacie czołowym, a także w mniejszym stopniu - w płacie ciemieniowym oraz prążkowiu. W afazji receptywnej dominowała zaś hipoperfuzja w okolicy skroniowej i ciemieniowej. Z kolei w afazji mieszanej niedobór krążenia mózgowego był najbardziej rozległy - obejmował cały obszar położony wokół bruzdy bocznej oraz struktury podkorowe. Wnioski. Tradycyjne klasyfikacje afazji oraz poglądy na ich neuroanatomiczne podłoże wymagają uzupełnienia o dane pochodzące z badań wykonanych za pomocą SPECT. W etiologii afazji naczyniowej ważną rolę pełnią uszkodzenia podkorowe. Tomografia emisyjna pojedynczego fotonu jest użyteczną metodą oceny i różnicowania zmian naczyniopochodnych wywołujących afazję.Background. A large variety of acquired aphasic syndromes can be correlated to relatively specific brain lesions located at distinct sites in the left cerebral hemisphere. The purpose of this article was to determine neuroanatomical correlates of aphasia following cerebrovascular accident. Material and methods. The research involved 30 stroke patients with a single left-hemisphere-damage lesion and residual mild to severe aphasia. Language, assessed by the Boston Diagnostic Aphasia Examination, was affected to various degrees by a wide range of pathologies. The single-photon emission-computed tomography (SPECT) images of the brain were acquired with 740 MBq (20 mCi) of Tc-99m-labeled ECD on a triple-headed gamma camera equipped with low-energy, high-resolution collimator. Comparisons of cerebral blood flow between patients with different types of aphasia were performed. Results. The most prominent perfusion abnormalities in expressive aphasia, as determined by the laterality index, were found in the frontal lobe, and to a lesser degree, the parietal lobe and striatum, whereas the most prominent deficits in receptive aphasia were found in the left temporal and parietal areas. In mixed aphasia, SPECT images evidenced the most extensive damage throughout the perisylvian region of the left hemisphere. Conclusions. There is a need for reinterpretation of the anatomical correlation of selected aphasic syndromes, especially classic expressive (Broca's) and receptive (Wernicke's) aphasias. The present study highlights the integrative role of some subcortical structures in language and speech functions. The results support the usefulness of regional cerebral blood flow SPECT imaging as a diagnostic aid in the post-stroke aphasias

Early recanalisation of middle cerebral artery in thrombolytic therapy of cardiogenic stroke - a case study

Udary niedokrwienne stanowią 85–90% udarów mózgu, większość z nich to rezultat niedrożności tętnic mózgowych lub szyjnych. Wysoka śmiertelność oraz znaczny odsetek chorych obarczonych trwałym inwalidztwem wskazują na konieczność poszukiwania skuteczniejszych form terapii. Tromboliza mózgowa pozwala na istotne zmniejszenie deficytu neurologicznego. W pracy przedstawiono przypadek 54-letniego mężczyzny, u którego zastosowano leczenie trombolityczne w przebiegu kardiogennego ogniska niedokrwiennego mózgu w dorzeczu tętnicy mózgu środkowej. Poprawa stanu neurologicznego (regresja objawów ogniskowych) nastąpiła już w pierwszej godzinie leczenia i.v. rekombinowanym tkankowym aktywatorem plazminogenu (rt-PA). Rekanalizację tętnicy mózgu środkowej potwierdzono badaniem przezczaszkowej ultrasonografii dopplerowskiej.Acute ischaemic stroke constitutes 85–90% of all stroke subtypes. Majority of brain ischaemia results from cerebral or carotid arteries occlusion. High mortality and invalidity due to stroke are still unsatisfactory. Thrombolytic therapy enables recovery improvement and significant reduction of neurological deficits. In this report we present a case of 54-year-old male with ischaemic stroke of cardiogenic origin in territory of middle cerebral artery. Significant neurological recovery was observed during the first hour of i.v. rt-PA infusion. Recanalisation of middle cerebral artrery was confirmed with Transcranial Doppler examination

Aging and Hypertension – Independent or Intertwined White Matter Impairing Factors? Insights From the Quantitative Diffusion Tensor Imaging

Aging disrupts white matter integrity, and so does continuous elevated blood pressure that accompanies hypertension (HTN). Yet, our understanding of the interrelationship between these factors is still limited. The study aimed at evaluating patterns of changes in diffusion parameters (as assessed by quantitative diffusion fiber tracking – qDTI) following both aging, and hypertension, as well as the nature of their linkage. 146 participants took part in the study: the control group (N = 61) and the patients with hypertension (N = 85), and were divided into three age subgroups (25–47, 48–56, 57–71 years). qDTI was used to calculate the values of fractional anisotropy, mean, radial and axial diffusivity in 20 main tracts of the brain. The effects of factors (aging and hypertension) on diffusion parameters of tracts were tested with a two-way ANOVA. In the right hemisphere there was no clear effect of the HTN, nor an interaction between the factors, though some age-related effects were observed. Contrary, in the left hemisphere both aging and hypertension contributed to the white matter decline, following a functional pattern. In the projection pathways and the fornix, HTN and aging played part independent of each other, whereas in association fibers and the corpus callosum if the hypertension effect was significant, an interaction was observed. HTN patients manifested faster decline of diffusion parameters but also reached a plateau earlier, with highest between-group differences noted in the middle-aged subgroup. Healthy and hypertensive participants have different brain aging patterns. The HTN is associated with acceleration of white matter integrity decline, observed mainly in association fibers of the left hemisphere

White matter integrity in dyskinetic cerebral palsy: Relationship with intelligence quotient and executive function

Background: Dyskinetic cerebral palsy (CP) is one of the most disabling motor types of CP and has been classically associated with injury to the basal ganglia and thalamus. Although cognitive dysfunction is common in CP, there is a paucity of published quantitative analyses investigating the relationship between white matter (WM) microstructure and cognition in this CP type. Aims: This study aims (1) to compare brain WM microstructure between people with dyskinetic CP and healthy controls, (2) to identify brain regions where WM microstructure is related to intelligence and (3) to identify brain regions where WM microstructure is related to executive function in people with dyskinetic CP and (4) to identify brain regions where the correlations are different between controls and people with CP in IQ and executive functions. Patients and methods: Thirty-three participants with dyskinetic CP (mean ± SD age: 24.42 ± 12.61, 15 female) were age and sex matched with 33 controls. Participants underwent a comprehensive neuropsychological battery to assess intelligence quotient (IQ) and four executive function domains (attentional control, cognitive flexibility, goal setting and information processing). Diffusion weighted MRI scans were acquired at 3T. Voxel-based whole brain groupwise analyses were used to compare fractional anisotropy (FA) and of the CP group to the matched controls using a general lineal model. Further general linear models were used to identify regions where white matter FA correlated with IQ and each of the executive function domains. Results: White matter FA was significantly reduced in the CP group in all cerebral lobes, predominantly in regions connected with the parietal and to a lesser extent the temporal lobes. There was no significant correlation between IQ or any of the four executive function domains and WM microstructure in the control group. In participants with CP, lower IQ was associated with lower FA in all cerebral lobes, predominantly in locations that also showed reduced FA compared to controls. Attentional control, goal setting and information processing did not correlate with WM microstructure in the CP group. Cognitive flexibility was associated with FA in regions known to contain connections with the frontal lobe (such as the superior longitudinal fasciculus and cingulum) as well as regions not known to contain tracts directly connected with the frontal lobe (such as the posterior corona radiata, posterior thalamic radiation, retrolenticular part of internal capsule, tapetum, body and splenium of corpus callosum). Conclusion:The widespread loss in the integrity of WM tissue is mainly located in the parietal lobe and related to IQ in dyskinetic CP. Unexpectedly, executive functions are only related with WM microstructure in regions containing fronto-cortical and posterior cortico-subcortical pathways, and not being specifically related to the state of fronto-striatal pathways which might be due to brain reorganization. Further studies of this nature may improve our understanding of the neurobiological bases of cognitive impairments after early brain insult