17 research outputs found

    Secondary thrombosis of the left internal carotid artery caused by a motor vehicle accident: a radiological case

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    rare case of occlusion of the internal carotid artery following a motor vehicle accident in a 34-year-old female victim who initially presented with clear consciousness and had normal computed tomogram of the brain is reported. Seven hours after the accident, the patient was unexpectedly diagnosed with the left hemisphere infarction, and two days later, she suffered from right hemiplegia and coma. The follow-up brain computed tomography scan showed an acute infarction of the left hemisphere of the cerebrum and severe cerebral edema. Anticoagulation therapy was administered, and emergency craniotomy for brain decompression was carried out. After 3.5 months, she was discharged and underwent regular follow-up in the outpatient department. Four years after the motor vehicle accident, the patient had intact awareness, was functionally independent, but remained with motor aphasia, right hand paralysis, and right leg paresis

    An Extremely Rare Case of Glioblastoma Multiforme of the Spinal Cord

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    Being the most common glial cell tumor of the adult brain, primary glioblastoma multiforme is an extremely rare but excessively devastating condition of the spinal cord. It presents with indistinctive magnetic resonance imaging findings, so the diagnosis is very complicated to make. A low-grade glioma may undergo a malignant transformation into glioblastoma multiforme in a very short period, critically impairing treatment possibilities and prognosis, so a correct and timely diagnosis is crucial. We report a case of intramedullary glioblastoma multiforme in a young man and describe the diagnostic difficulties and devastating progression of the entity

    Adjustment of ultrasound exposure duration to microbubble sonodestruction kinetics for optimal cell sonoporation in vitro

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    Cell sonoporation enables the delivery of various exogenous molecules into the cells. To maximize the percentage of reversibly sonoporated cells and to increase cell viability we propose a model for implicit dosimetry for adjustment of ultrasound (US) exposure duration. The Chinese hamster ovary cell suspension was supplemented with microbubbles (MB) and exposed to US, operating at the frequency of 880_kHz, with a 100% duty cycle and with an output peak negative pressure (PNP) of 500_kPa for durations ranging from 0.5 to 30_s. Using diagnostic B-scan imaging we showed that the majority of the MB at 500_kPa US peak negative pressure undergo sonodestruction in less than a second. During this time maximal number of reversibly sonoporated cells was achieved. Increase of US exposure duration did not increase sonoporated cell number, however it induced additional cell viability decrease. Therefore aiming to achieve the highest level of reversibly sonoporated cells and also to preserve the highest level of cell viability, the duration of US exposure should not exceed the duration needed for complete MB sonodestructionBiologijos katedraKauno technologijos universitetasVytauto Didžiojo universiteta

    Microbubble sonodestruction rate as a metric to evaluate sonoporation efficiency

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    Objectives. The efficiency of sonoporation is directly related to microbubble cavitation and can be dependent on the microbubble sonodestruction rate. The objective of this study was to investigate whether the rate of microbubble sonodestruction can be used as a parameter to develop an implicit dosimetric method for sonoporation efficiency evaluation. Methods. To evaluate the rate of microbubble sonodestruction as a function of the ultrasound (US) peak negative ultrasound pressure, 12-MHz diagnostic US was used in the B-scan mode. Chinese hamster ovary cells were exposed to therapeutic US at 880 kHz in the absence or presence of microbubbles. The sonoporation efficiency was evaluated by the sonotransfer of bleomycin, a cytotoxic, membrane-impermeable anticancer drug. Results. At a low microbubble sonodestruction rate of 1/τ < 0.5 second–1 (τ providing the time necessary to decrease the microbubble concentration to 37% of its initial value), cell viability remained basically unaffected, but the percentage of sonoporated cells did not reach 10%. At higher microbubble sonodestruction rates, the efficiencies of irreversible and reversible sonoporation started to increase linearly and reached the plateau at 5 seconds–1. Conclusions. These results show that the microbubble sonodestruction rate can be used to predict the percentage of reversible and irreversible sonoporationBiologijos katedraKauno technologijos universitetasVytauto Didžiojo universiteta

    Relationship between echocardiographic and magnetic resonance-derived measurements of the thoracic aorta in turner syndrome patients

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    Introduction. Turner syndrome (TS) is assigned to the rare diseases group. Morbidity and mortality of TS patients are high, particularly due to the cardiovascular disorders, so monitoring for cardiovascular complications must be ensured. The data demonstrate a strong correlation between 2-dimensional echocardiographic (2Decho) evaluation and magnetic resonance imaging (MRI); still, according to recent guidelines, MRI remains a gold standard. In this study, we aimed to compare aortic dimensions on MRI and 2Decho in TS patients. Methods. 50 TS patients (≥18 years) were enrolled into the cross-sectional study. 2Decho and MRI were performed. The measurements of the aorta were assessed in five standard positions on 2Decho and in 9 standard positions on MRI; ASI (aortic size index) of the ascending aorta was calculated since reduced adult height is observed in TS patients. Results. ASI on echocardiography strongly correlated with ASI on MRI in all positions of the ascending aorta, but significantly larger medians of ASI were found on 2Decho in all positions of the ascending aorta and arch when compared with MRI measurements. Still, the prevalence of aortic sinus dilation was significantly and more frequently (52% vs. 38%, ) observed on MRI when compared with 2Decho. Conclusion. The relation of aortic size was significant in all positions when comparing the MRI and 2Decho methods; still, the dilatation of the sinus of aorta was more frequently found on MRI compared with echocardiography

    Diffusion-weighted magnetic resonance enterocolonography in assessing Crohn's disease activity

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    Introduction: Diffusion-weighted magnetic resonance imaging (DWI- MRI) has the potential for identifying inflamed bowel segments for patients with Crohn's disease (CD). Objectives: We aimed to determine diffusion-weighted imaging (DWI) value to predict active CD and compare apparent diffusion coefficients (ADC) with endoscopic and conventional magnetic resonance imaging (MRI) CD activity indices. Patients and Methods: Overall, 229 patients with suspected and diagnosed CD prospectively underwent magnetic resonance enterocolonography (MR-EC) with DWI sequence and ileocolonoscopy. Magnetic resonance activity index (MaRIA), Clermont index, and CD endoscopic index of severity (CDEIS) were calculated. Results: Of the 229 investigated patients, the clinical diagnosis of CD was confirmed in 100 persons. DWI score ≥2 had 96.9% sensitivity and 82.3% specificity for diagnosing CD. A threshold ADC value of 1.30 × 10–3 mm2 /s can distinguish between normal and inflamed bowel segments with a sensitivity of 73.8% and a specificity of 98%. While using MaRIA, the threshold ADC value of 1.32 × 10–3 mm2 /s with a sensitivity of 97.9% and a specificity of 97.8% was established. There were significant differences in the DWI scores and ADC values comparing patients with inactive, mild, moderate-severe disease (P < 0.01). ADC correlated with MaRIA-G (global) (r = −0.69, P = 0.001), Clermont-G (r = −0.722, P = 0.001) and CDEIS (r = −0.69, P = 0.001). Conclusions: DWI is a valuable tool that is able to identify inflamed bowel segments as accurate as a conventional MaRIA score and to discriminate between mild and moderate and severe CD activity

    Ultrasonography and Magnetic Resonance Imaging of the Brain in Hypoxic Full-Term Newborns

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    The aim of this article was to review the studies on diagnostic and prognostic value of radiological investigations (cranial sonography, Doppler ultrasonography, and magnetic resonance imaging) in the detection of hypoxic-ischemic brain injuries in full-term newborns. Materials and Methods. A systematic search of studies on the diagnostic and prognostic possibilities of radiological investigations for the detection of hypoxic-ischemic injuries in full-term newborns was performed. Results. A total of 13 prospective and 4 retrospective studies that analyzed the incidence of hypoxic-ischemic cerebral injuries, determined by means of cranial sonography, Doppler sonography, and magnetic resonance imaging, and associations with the stages of hypoxic-ischemic encephalopathy and long-term neurodevelopmental outcomes were included in this systematic review. Conclusions. Magnetic resonance imaging detects lesions in 75%–100% of cases. Magnetic resonance imaging performed at the age of 7–11 days demonstrated a high sensitivity (100%) and negative predictive value (100%) to predict unfavorable outcomes at 4 years of age. In newborns with hypoxic-ischemic encephalopathy, substantial cerebral hemodynamic alterations are detected after birth. The sensitivity and negative predictive value of cerebral blood flow velocities (peak systolic flow velocity, end-diastolic flow velocity) changes at 12±2 hours of age to predict the severity of hypoxic-ischemic encephalopathy and unfavorable outcomes at 18 months of age were found to be high (90% and 94%, respectively). A low resistive index (&lt;0.56) at the age of 1–3 days had a specificity of 95% to predict unfavorable outcomes at 3 years of age. The data on the diagnostic and prognostic potential of cranial sonography are limited scarce and contrary

    Mapping microbubble and ultrasound spatio-temporal interaction by M-mode imaging: the study of feasibility

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    Ultrasound (US) and microbubble (MB) interaction is an important factor in the research of bioacoustics, as well as targeted drug and gene delivery. In this study, we demonstrate the feasibility of pulse−echo M-mode imaging system to be used for the visualization and quantification of US–MB interaction in both spatial and temporal dimensions. The system incorporates an exposure chamber with the cell– MB suspension, a 2.7 MHz focused US transducer, a US pulser–receiver and the customized LabView software. The results of cell and MB interaction obtained after M-mode image analysis have showed the US–MB interaction to be non-uniform in space and non-stationary in time. In order to quantify the spatio-temporal US–MB interaction, we have introduced the time function of spatial homogeneity dynamics. We have observed that the effective duration of interaction can be characterized at the predefined threshold of spatial homogeneity. For example, at the US excitation of 360 kPa peak negative pressure (15 bursts transmitted at 80 Hz pulse repetition frequency), the US–MB interaction persists for more than 5 seconds in the range at 4 mm depth of the exposure chamber with more than 50% of homogeneity. The system proposed in this assay is feasible for the characterization of US–MB interaction and can be exploited to optimize the MB concentration and/or the US excitation parametersBiochemijos katedraBiologijos katedraKauno technologijos universitetasVytauto Didžiojo universiteta
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