This article is written to commemorate the 40th year of the scientific career of Professor Maria Pąchalska, Head of the Department of Neuropsychology and Neurorehabilitation at Krakow University, President of the Polish Neuropsychological Society, and the Editor-in-chief of Acta Neuropsychologica, with whom I have been collaborating for over ten years. The subject matter of our work includes the introduction of HBI methodology to clinics and the search for neuromarkers in particular disease entities. What is the new methodology we are talking about? In general, we think of a biomarker (or biological marker) as a characteristic that can be objectively measured and evaluated as an index of normal or pathological biological processes. For disorders of the central nervous system, biomarkers can be classified as clinical, neuroimaging, biochemical or genetic, according to the type of information they provide. Expectations for the development of biomarkers are high, since they could lead to a significant improvement in diagnosing and possibly preventing neurological and psychiatric diseases. Neuroimaging is an array of neuroscience methods that include the techniques of magnetic resonance imaging (MRI), functional MRI (fMRI), and PET (positron emission tomography), as well as Electroencephalogram (EEG) and Magnetoencephalogram (MEG) techniques, such as quantitative EEG (QEEG), event related de/synchronization (ERD/ERS) and event-related potentials (ERPs).
The article is a review of neuroimaging studies performed during the Stroop paradigm based tasks among individuals suffering from unipolar and bipolar depression. The aim of the article is to highlight the validity od Stroop paradigm in neuropsychological and neuropsychiatric diagnosis of depressin, used as a tool for assessing cognitive functioning, but also claryfying the etiopathology of depressive disorders. The first of the article is a review of previous reports, describing resting brain activity abnormalities in affective disorders called neurocorrelates of depression. Then the most common cognitive dysfunctions represented by unipolar and bipolar patents will be discussed brefly and the impact of these dysfuctionts on Stroop test performance. In the last two parts of the article you can find a review of neuroimaging studies during Stroop task performance among healthy individuals and also the comparisons of brain activity during the Stroop interference effect in the group of healthy and depressive subjects. Different brain activity during stroop task among patients suffering from depression comaring with healthy individuals and some differences in brain pattern during the same cognitive task among unipolar and bipolar individuals may indicate the validity of Stroop test in neuropsychological and neuropsychiatric diagnosis.
Patients after severe brain injury are often unable to communicate, move on their own or show evidence of a purposeful behaviour, yet at the same time they may remain conscious. Such states are referred to as disorders of consciousness. Their clinical diagnosis, as based on complex behavioural criteria, is still prone to error and may lead to ambiguous cases. This article is an overview of the recent experimental approaches aimed at the assessment of the structure and function of the central nervous system, based on neuroimaging and employing the current knowledge regarding the mechanisms of consciousness. All these approaches are aimed at identifying the most efficient measure to enable a reliable diagnosing. The first approach is based on structural imaging that provides information on the organisation and state of neural connections within the brain. Other approaches are functional studies divided into passive and active ones. Passive paradigms evaluate the ability of the neural networks in the patient’s brain to sustain consciousness without them having to take part in an experimental task, while the active ones enable the assessment of the state of consciousness on the basis of neural correlates of volitional activities recorded as the patient performs mental tasks. The latter approach rests on an assumption that volitional activity requires conscious processing and cannot be explained in terms of stereotypic reaction to stimulation. While a significant number of approaches presented herein works quite well with respect to differentiating the states on the group level, still only a few of them allow such differentiation on the level of an individual patient. On the latter level, the most important challenge (when it comes to choose a particular care for a patient) could be carried out by a complementary use of several methods at the same time or the evaluation of brain function based on various neuroimaging techniques (EEG and fMRI).
Introduction: Neuroimaging is a standard examination implemented for diagnosis of various pathologies of the central nervous system. The fundamental diagnostic procedures in medical imaging of the central nervous system are computed tomography and magnetic resonance imaging. In case of a sudden focal or generalized onset of brain dysfunctions at first we should think about stroke. A very important test if stroke is suspected is computed tomography. In this paper we would like to check if it is possible to distinguish two pathologies of the cerebrum: ischaemic stroke and tumour, using quantitative analysis of selected abnormalities. Material and methods: Analysis is based on comparison of two pathologies (ischaemic stroke and tumour). Two sets of images were prepared. Analysis is performed to distinguish abnormalities observed on computed tomography brain images from healthy tissue. The image analysis includes data conversion, normalization of region of interest, estimation of the number of texture features, features selection based on four different methods of selection and finally classification based on artificial neural network classifier. Results: In the examination, different effectiveness of used methods was observed. Quantitative analysis of selected texture features allows to differentiate two classes of pathologies. Also an important observation is that the artificial neural network can be a useful tool in data classification and analysis. Conclusions: The performed analysis is effective but only for small number of data. That is why it still needs to be conducted on a larger set of data. It will be also necessary to repeat classification a number of times and to perform data validation in order to confirm effectiveness of the presented method. After that we can hope to get really satisfying results.
PL
Wstęp: Neuroobrazowanie jest standardowym badaniem stosowanym w diagnostyce ośrodkowego układu nerwowego (OUN). Podstawowymi narzędziami diagnostycznymi w obrazowaniu OUN są tomografia komputerowa (TK) oraz rezonans magnetyczny. W przypadku wystąpienia nagłych ogniskowych lub uogólnionych objawów neurologicznych należy w pierwszej kolejności podejrzewać udar mózgu. Obecnie badaniem pierwszego rzutu w diagnostyce neuroradiologicznej jest badanie TK. W przedstawionej pracy podjęto próbę sprawdzenia, czy jest możliwa ilościowa analiza obrazów TK, pozwalająca odróżnić zmiany rozrostowe OUN od udarów niedokrwiennych. Materiały i metody: Analizę oparto na porównaniu dwóch patologii OUN: udaru niedokrwiennego oraz zmiany rozrostowej. Ocenie poddano obrazy TK mózgowia, na których wyodrębniono zmianę patologiczną. Podczas kolejnych etapów pracy przeprowadzono: konwersję danych, definiowanie obszarów zainteresowania (ROI), estymację cech tekstury, selekcję cech z zastosowaniem czterech różnych metod oraz klasyfikację opartą na sztucznej sieci neuronowej. Wyniki: Odnotowano różną skuteczność zastosowanych metod, co dało podstawę do stwierdzenia, że ilościowa analiza wybranych cech tekstury obrazu pozwala odgraniczyć klasy przypisane do omawianych patologii, natomiast użycie sztucznych sieci neuronowych do klasyfikacji danych wskazuje na ich skuteczność i przydatność jako narzędzi stosowanych w analizie wybranych danych. Podsumowanie: W sytuacji gdy badanie neuroradiologiczne nie wypada jednoznacznie, a leczenie udaru i guza mózgu różnią się diametralnie, istnieje możliwość zastosowania przedstawionej analizy w celu skrócenia czasu potrzebnego do postawienia właściwej diagnozy. Przedstawione wyniki mają jednak charakter wstępny i wymagają dalszej analizy na większej grupie pacjentów.
The cervical myelopathy (CM) belongs to the civilization diseases connected to age. The symptoms of the disease were well known from many years after yet the neuroradiological examinations (CT or NMR) can confirmed the diagnosis of cervical myelopathy. In 1928 year Stookey presented the theory of CM aetiology, since other authors have formed their opinions or modified Stookey’s theory. Now is established that the cervical myelopathy is the effects from following abnormalities: 1) the direct pressure of the bone, osteochondrosis or its calcifications changes to spinal cord; 2) the ischaemic changes to cause by pressure to the spinal cord vessels; 3) repetitive microtraumas connected whit the flexion or extension movements of the neck. It is considered that CM develops when the diameter of canal vertebralis narrows by 30%. The spinal cord gets flattened in the anterior-posterior size. Few anatomopathological investigations have shown that on the level of the lesions were observed gliosis or demyelination of the spinal cord. The lateral columns of the spinal cord are more prone to the pressure than anterior or posterior one. The osteochondrosis as the osteophytes are present in 90% of people over 60 years. The initial symptoms of CM are headache or pain of the neck. Later the pain is radiated to shoulders or brachium, the upper limbs weaken, the patient is feeling paresthesias mostly in palms. After some time the lower limbs were found less efficiency and spastic rigidity. The gait to turn slowly and clumsy. The disturbances with continence of urine was also appeared. The muscles atrophy, mainly hands, have been observed as well as impaired deep sensation or vibration. Is characterized the hyperreflexia in upper and lower limbs. Sometimes is appeared a patellar clonus as well as the Lhermitte’s sign. In the differential diagnosis should be taken under consideration many diseases, but the results of the neuroradiological examination should be a decisive factor. We should remember also that the examination of the cerebrospinal fluid is normal. The CM is disease of the slowly progressive course. The surgical treatment of the disease might give better results in the initial stage of the disease – 30% of patients reported the improvements in their condition. In 2 to 3 years after the surgery the symptoms reoccur and the neurological status of the patients is similar to those who have been treated in the conservative way.
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