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Metody obrazowania udaru niedokrwiennego mózgu w fazie ostrej

Kidoń Joanna, Lasek-Bal Anetta

Inżynier i Fizyk Medyczny

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2022

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Vol. 11, nr 5

407--412

PL

Udar mózgu stanowi jedną z wiodących przyczyn niepełnosprawności oraz śmierci na świecie. Pomimo spadku śmiertelności z powodu udaru mózgu, globalne obciążenie udarem wzrasta. Udar niedokrwienny charakteryzuje niejednorodny patomechanizm, począwszy od obrzęku cytotoksycznego (minuty od wystąpienia incydentu mózgowo-naczyniowego), obrzęku naczyniopochodnego (od 6 godzin), po procesy naprawcze (neuroangiogeneza, neurogeneza) w fazie podostrej i przewlekłej. Do podstawowych technik obrazowania udaru niedokrwiennego mózgu zaliczyć należy przede wszystkim tomografię komputerową (celem wyeliminowania ewentualnego krwawienia, innych przyczyn pogorszonego stanu neurologicznego), rezonans magnetyczny (techniki: dyfuzyjne, saturujące sygnał płynu mózgowo-rdzeniowego, podstawowe, podatności magnetycznej), angiografię (CT, MRI, DSA) oraz ultrasonografię. Techniki dyfuzyjne oraz perfuzyjne (CT, MRI, SPECT, PET) służą do oceny rozległości strefy półcienia. Techniki dyfuzyjne mają szczególne znaczenie w ocenie czasu wystąpienia incydentu mózgowo- naczyniowego. Uważa się, że DWI poprawia wykrywalność udarów niedokrwiennych mózgu aż do 95% w porównaniu ze standardowymi technikami obrazowania. Korelacja map ADC i obrazów DWI pozwala zidentyfikować obszary niedokrwienia. W obrazach DWI sygnał jest hiperintensywny w ciągu kilku minut od incydentu zawałowego, natomiast ADC wykazuje obniżone wartości w czasie od pierwszego do czwartego dnia, w piątej do dziesiątej dobie ma miejsce ich wzrost, po czym następuje wyrównanie względem tkanki zdrowej.

EN

Stroke is one of the leading causes of disability and death in the world. Despite the decline in stroke mortality, the global burden of stroke is increasing. Ischemic stroke is characterized by a heterogeneous pathomechanism, ranging from cytotoxic edema (minutes from the occurrence of a cerebrovascular accident), vasogenic edema (from 6 hours), to repair processes (neuroangiogenesis, neurogenesis) in the subacute and chronic phases. The basic techniques of ischemic stroke imaging include, first of all, computed tomography (to eliminate possible bleeding, other causes of deteriorated neurological condition), magnetic resonance (techniques: diffusion, saturating the cerebrospinal fluid signal, basic, magnetic susceptibility), angiography (CT, MRI, DSA) and ultrasound. Diffusion and perfusion techniques (CT, MRI, SPECT, PET) are used to assess the extent of the penumbra. Diffusion techniques are of particular importance in assessing the timing of a cerebrovascular accident. DWI is believed to improve the detection of ischemic strokes by up to 95% compared to standard imaging techniques. Correlation of ADC maps and DWI images identifies ischemic areas. In DWI images the signal is hyperintense within a few minutes of the infarction incident, while the ADC shows decreased values from the first to the fourth day, on the fifth to the tenth day their increase takes place, followed by compensation for healthy tissue.

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Ocena skuteczności ćwiczeń kończyny górnej, wykonywanych w przestrzeni wirtualnej przy zastosowaniu biologicznego sprzężenia zwrotnego, u pacjentów po udarze niedokrwiennym mózgu – doniesienia wstępne

Wieczorek Michał, Makuch Maciej

Aktualne Problemy Biomechaniki

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2019

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z. 17

123--130

PL

Celem badań była ocena wpływu programu rehabilitacji pacjentów po udarze na funkcjonalność, motorykę, zakresy ruchomości oraz wartości siły kończyny górnej, uzupełnionego o ćwiczenia w przestrzeni wirtualnej oraz porównanie osiągniętych wyników z grupą kontrolną. Do oceny stanu funkcjonalnego pacjentów użyto testów Fugl-Mayer Motor Assessment, Frenchy Arm Test oraz skali Lovetta. Dokonano pomiarów zakresu ruchomości w stawach barkowym, promieniowo-nadgarstkowym (płaszczyzny: czołowa i strzałkowa), łokciowym, jak również zmierzono wartości siły chwytów: cylindrycznego, szczypcowego, bocznego i trójpunktowego.

EN

The aim of the study was to assess the impact of post-stroke rehabilitation program on functionality, motor skills, mobility ranges and upper limb strength values, supplemented with VR exercises and comparison of the results obtained with the control group. The Fugl-Mayer Motor Assessment, the Frenchy Arm Test and the Lovett scale were used to assess the functional status of the patients. Measurements of the range of motion in shoulder, radial-wrist joints (planes: frontal and sagittal) and elbow were measured, as well as the values of grip strength: cylindrical, pincer, lateral and three-point.

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Attribute selection for stroke prediction

Zdrodowska Małgorzata

Acta Mechanica et Automatica

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2019

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Vol. 13, no. 3

200--204

EN

Stroke is the third most common cause of death and the most common cause of long-term disability among adults around theworld. Therefore, stroke prediction and diagnosis is a very important issue. Data mining techniques come in handy to help determine the correlations between individual patient characterisation data, that is, extract from the medical information system the knowledge necessary to predict and treat various diseases. The study analysed the data of patients with stroke using eight known classification algorithms (J48 (C4.5), CART, PART, naive Bayes classifier, Random Forest, Supporting Vector Machine and neural networks Multilayer Perceptron), which allowed to build an exploration model given with an accuracy of over 88%. The potential features of patients, which may be factors that increase the risk of stroke, were also indicated.

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Conceptual improvements in computer-aided diagnosis of acute stroke

Jóźwiak R., Przelaskowski A., Ostrek G.

Journal of Medical Informatics & Technologies

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2011

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Vol. 17

191--199

EN

This work presents some conceptual improvements in assistance of acute stroke diagnosis with Stroke Monitor - computer-aided diagnosis tool developed and elaborated by Telemedicine Group from Institute of Radioelectronics, Warsaw University of Technology. Based on statistical analysis of common error sources we proposed some ideas of improvement capabilities for false positive errors reduction. Simulation and experimental verification confirmed validity of further development directions.

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Multiscale extraction of diagnostic content applied for CT brain examination

Przelaskowski A., Ostrek G., Sklinda K.

Biocybernetics and Biomedical Engineering

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2009

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Vol. 29, no. 4

25-40

EN

This paper presents the estimation methods of subtle hypodense changes of brain tissue in noncontrast CT scans. The purpose of reported research is improved detection of direct signs of hyperacute ischemic stroke. Proposed tool is nonlinear approximation in base of multiscale functions with respective thresholding. Different rationales for best basis selection were considered. Several local bases including wavelets, curvelets, contourlets and wedgelets were considered and characterized with a criterion of as fast as possible approximation error decay. Adaptive thresholding was suggested for defining of nonlinear approximation space for different image models. Procedures of estimation and extraction of diagnostic information were experimentally verified. Improved diagnosis of acute stroke eases was reported.

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The diseases classification method on gait abnormalities characteristic contributions

Chandzlik S., Piecha J.

Journal of Medical Informatics & Technologies

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2005

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Vol. 9

187--194

EN

Present medicine uses computers in various applications, especially in a field of a diseases level classification and diagnosis. In many cases an automatic conclusion making units are the main goal of the computer systems usage. The software units are developed for the diseases classification or for monitoring of the disease medical treatment. An example application was described in this paper. It concerns a gait abnormalities level analysis that is described by a data records gathered by insoles of Parotec System for Windows (PSW) [17,18]. The PSW software package is used for visualisation of the gait characteristic static and dynamic characteristic features. In the authors' works many additional data components were distinguished. The field of the applications is located within the neurological gait characteristics also the source applications concern orthopaedics [16,18]. Careful analysis of the data provided the developers with new areas the PSW applications [4,11,13]. For conclusion making units the artificial networks theory was implemented [2,4,11,13]. For more effective training of the neural networks specific characteristic measures were introduced [4,5]. They allow controlling the training process more precisely, avoiding mistakes in current records classification.