40 results on '"Szarmach A"'
Search Results
2. Association between Clinical Manifestations in Temporomandibular Joint Disorders and Corresponding Radiographic Findings.
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Wojciechowska B, Szarmach A, Michcik A, Wach T, and Drogoszewska B
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Background : Temporomandibular disorders are common conditions characterized by discomfort within the temporomandibular joints, acoustic changes, and restricted mandibular movement. Accurate diagnosis and subsequent treatment rely heavily on clinical examination, but it is often necessary to add radiological examinations to the diagnostics. Magnetic Resonance Imaging (MRI) is the gold standard for visualizing the disc, while cone-beam computed tomography (CBCT) is primarily used for evaluating condylar morphology. Ultrasound (US) serves as a real-time imaging modality for soft tissues. The objective of the present study was to explore the association between clinical manifestations observed in patients with temporomandibular joint disorders and corresponding radiographic findings. Methods : A total of 63 adult patients (51 female and 12 male) with temporomandibular joint disorders were included in this cross-sectional study. Each patient underwent a clinical examination, followed by appropriate radiological examinations (MRI, CBCT, or US). The level of statistical significance was set at an alpha of 0.05. The Shapiro-Wilk test assessed the normality of numerical variables. The Wilcoxon rank sum test compared two independent groups with non-normally distributed data. Relationships between categorical variables were evaluated using the Pearson chi-square test or Fisher's exact test. The Kendall tau (τ) method analyzed the correlation between two binary variables. Results : The analysis included 63 patients with TMD, predominantly females (80.95%). Ages ranged from 18 to 74 years with a median of 39 years. In the CBCT study, we observed rarefied changes in the left bone structures in patients with bruxism ( p = 0.010). MRI and ultrasound imaging revealed changes in patients with limited jaw opening: erosions in the right mandibular head on ultrasound ( p = 0.008) and abnormal right bone structures on MRI ( p = 0.009). In CBCT, asymmetry in the left joint space was correlated with a high incidence of right side muscle tension ( p = 0.004). Additionally, both CBCT and ultrasound showed a correlation between muscle tension and erosion ( p = 0.040 in ultrasound, p = 0.020 in CBCT). Acoustic changes, when compared with radiological imaging, were evident in all three studies, like temporomandibular joint pain or palpation. Conclusions : Our study compared three radiographic imaging methods with clinical examinations to assess their correlation with clinical symptoms. Each imaging technique provided unique insights depending on the specific symptoms presented. The observed correlations varied, highlighting the unique contributions of each modality to the diagnostic process. This underscores the importance of employing multiple diagnostic approaches for a thorough assessment of the temporomandibular joint. However, a limitation of our study is the small sample size and the uneven distribution of participants among the groups. Additionally, not all patients underwent every imaging modality.
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- 2024
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3. Redefining Radiation Metrics: Evaluating Actual Doses in Computed Tomography Scans.
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Sabiniewicz-Ziajka D, Szarmach A, Grzywińska M, Gać P, and Piskunowicz M
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Background: Computed tomography (CT) contributes significantly to the collective dose from medical sources, raising concerns about potential health risks. However, existing radiation dose estimation tools, such as volume computed tomography dose index (CTDIvol), dose-length product (DLP), effective dose (ED), and size-specific dose estimate (SSDE), have limitations in accurately reflecting patient exposure. This study introduces a new parameter, size-specific dose-length product (DLPss), aiming to enhance the precision of radiation dose estimation in real-life scenarios., Methods: A retrospective analysis of 134 chest CT studies was conducted. Relationships between CTDIvol and anthropometric parameters were examined, and SSDE was calculated based on effective diameter. Additionally, the novel parameter, DLPss, was introduced, considering scan length and cross-sectional dimensions., Results: Analysis reveals variations in scan length, effective diameter, and CTDIvol between genders. Strong correlations were observed between CTDIvol and effective diameter, particularly in men. The average CTDIvol for the entire group was 7.83 ± 2.92 mGy, with statistically significant differences between women (7.38 ± 3.23 mGy) and men (8.30 ± 2.49 mGy). SSDE values showed significant gender differences, with men exhibiting higher values. The average SSDE values for women and men were 9.15 ± 2.5 mGy and 9.6 ± 2.09 mGy, respectively, with a statistically significant difference ( p = 0.03). The newly introduced DLPss values ranged around 343.90 ± 81.66 mGy·cm for the entire group, with statistically significant differences between women (323.53 ± 78.69 mGy·cm) and men (364.89 ± 79.87 mGy·cm) ( p < 0.05), providing a comprehensive assessment of total radiation dose., Conclusion: The study highlights the need for accurate radiation dose estimation, emphasizing the impact of CT examination parameters on dose variability. The proposed DLPss parameter offers a promising approach to enhancing precision in assessing radiation risk during CT scans. Further research is warranted to explore additional parameters for a comprehensive understanding of radiation exposure and to optimize imaging protocols for patient safety.
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- 2024
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4. Physical activity and the brain myelin content in humans.
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Kujawa MJ, Marcinkowska AB, Grzywińska M, Waśkow M, Romanowski A, Szurowska E, Winklewski PJ, and Szarmach A
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New imaging sequences and biophysical models allow adopting magnetic resonance imaging (MRI) for in vivo myelin mapping in humans. Understanding myelination and remyelination processes in the brain is fundamental from the perspective of proper design of physical exercise and rehabilitation schemes that aim to slow down demyelination in the aging population and to induce remyelination in patients with neurodegenerative diseases. Therefore, in this review we strive to provide a state-of-the art summary of the existing MRI studies in humans focused on the effects of physical activity on myelination/remyelination. We present and discuss four cross-sectional and four longitudinal studies and one case report. Physical activity and an active lifestyle have a beneficial effect on the myelin content in humans. Myelin expansion can be induced in humans throughout the entire lifespan by intensive aerobic exercise. Additional research is needed to determine (1) what exercise intensity (and cognitive novelty, which is embedded in the exercise scheme) is the most beneficial for patients with neurodegenerative diseases, (2) the relationship between cardiorespiratory fitness and myelination, and (3) how exercise-induced myelination affect cognitive abilities., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kujawa, Marcinkowska, Grzywińska, Waśkow, Romanowski, Szurowska, Winklewski and Szarmach.)
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- 2023
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5. Contrast-enhanced ultrasound of adrenal hemorrhage: a helpful problem solving tool.
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Piskunowicz M, Stefanowicz J, Batko T, Hwang M, Świętoń D, Szarmach A, Back S, and Kosiak W
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- Child, Child, Preschool, Hematoma, Hemorrhage, Humans, Infant, Newborn, Problem Solving, Retrospective Studies, Ultrasonography methods, Adrenal Gland Diseases diagnostic imaging, Contrast Media
- Abstract
Aims: A focal lesion in the region of the adrenal gland in a newborn often requires further assessment. Ultrasound (US) is the initial imaging method of choice in young children as it does not use radiation or require sedation and it has excellent spatial resolution. In this case series, we present contrast-enhanced ultrasound (CEUS) as a problem-solving tool in the evaluation of neonatal adrenal lesions., Material and Methods: The imaging and medical records of five patients with adrenal lesions were retrospectively reviewed. All patients underwent US as an initial examination and all had US follow-up. Additionally, two patients had MRI examinations. CEUS was performed in all patients as a follow up examination. The enhancement characteristics of the adrenal masses on CEUS were analyzed with the use of VueBox software. In addition, qualitative analysis of the cine loops for the presence of vascularization within the lesions was performed by consensus between two radiologists., Results: The presence of an adrenal hematoma was correctly detected and characterized by CEUS in all five cases using VueBox perfusion analysis. Adrenal hematomas had no internal perfusion and flat time intensity curves., Conclusion: The quantitative and qualitative CEUS assessment of the mass can distinguish hemorrhage from a malignant lesion. Based on our findings, CEUS could serve as an alternative diagnostic tool to magnetic resonance imaging in the diagnosis of slowly resolving NAH lesions.
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- 2022
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6. Diagnostic value of diffusion tensor imaging in patients with clinical signs of cervical spondylotic myelopathy.
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Skotarczak M, Dzierżanowski J, Kaszubowski M, Winklewski PJ, Romanowski A, Szurowska E, and Szarmach A
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- Adult, Cervical Vertebrae surgery, Constriction, Pathologic complications, Constriction, Pathologic pathology, Diffusion Tensor Imaging methods, Humans, Spinal Cord Diseases diagnostic imaging, Spinal Cord Diseases surgery, Spondylosis complications, Spondylosis diagnostic imaging, Spondylosis surgery
- Abstract
Aim of the Study: The aim of this study was to assess the diagnostic value of diffusion tensor imaging (DTI) in patients with symptoms of cervical myelopathy. Detailed goals included determining the diagnostic effectiveness of quantitative parameters, i.e. fractional anisotropy (FA) and apparent diffusion coefficient (ADC), in the diagnosis of cervical myelopathy, and the correlation between these parameters and clinical symptoms., Clinical Rationale for the Study: The demonstration of an ischaemic focus in the spinal cord by standard magnetic resonance imaging (MRI) methods is associated with already accomplished spinal cord damage, and of course limited treatment options. Therefore, finding a new examination protocol that allows early diagnosis of myelopathic focus, before the onset of full neurological symptoms, has become a priority in the diagnosis and treatment of spine diseases. Such an examination increases the chances of correctly qualifying the patient for conservative vs. surgical treatment., Material and Methods: Between 2013 and 2017, 128 adults with clinical signs of cervical myelopathy were examined, and were divided into four symptomatic subgroups. A control group consisted of 37 healthy volunteers. DTI values were measured at the level of C2/C3, and at the most severe stenosis of the spine., Results: In patients with cervical spondylotic myelopathy (CSM), the ADC values were significantly higher (p < 0.001), and FA values were significantly lower (p < 0.001), than in healthy volunteers at the stenotic level. There were significant differences in DTI parameters between the clinical subgroups (p < 0.001)., Conclusions and Clinical Implications: Changes in DTI parameters indicate a microstructural disorder of the core which is not visible in a structural MRI. FA and ADC values measured at the level of the most severe stenosis of the spinal canal allow the differentiation of patients with myelopathy of varying degrees of clinical severity. Extending standard MRI to include assessment of FA and ADC may be helpful in deciding treatment modalities (conservative vs. surgical) for patients with visible canal stenosis without full neurological symptoms. This may be useful in selecting patients for urgent rehabilitative treatment. This study is a starting point for further research, i.e. an evaluation of the extent of FA and ADC lesion withdrawal after surgical treatment.
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- 2022
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7. The usefulness of selected sequences of magnetic resonance imaging in a diagnostic model for Crohn's disease.
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Tomicka-Szymanska B, Kaszubowski M, Winklewski PJ, Pienkowska J, Wypych J, Janiak M, Szarmach A, and Szurowska E
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Introduction: We hypothesized that, based on magnetic resonance enterography (MRE) and the apparent diffusion coefficient (ADC), measured in the affected parts of the intestine, it is possible to effectively differentiate active and chronic phases of Crohn's disease., Aim: To create a multidimensional diagnostic model for differentiating between the phases of Crohn's disease., Material and Methods: This study included 125 patients - 55 women (aged 19 to 66 years) and 70 men (aged 12 to 67 years) - who underwent MRE and ADC measurement for the first time., Results: The group of potential explanatory variables comprised 11 variables, including the thickness and length of the occupied section, number of lymph nodes, layered bowel wall enhancement, total transitions on fat tissue, and features of restricted diffusion. The final discrimination model was based on 2 variables: ADC (A) and layered bowel wall enhancement (W). Active Crohn's disease was defined as -6.339 + 4.747 × W + 0.008 × A, while chronic Crohn's disease was defined as -11.365 + 2.812 × W + 0.012 × A. Definitive diagnosis was based on histological examination of material collected during ileocolonoscopy in 96 patients, surgery with subsequent histopathological examination in 17 patients, and capsule endoscopy in 12 patients., Conclusions: The predictive model described here could identify the active form of Crohn's disease with a probability of 93.06% and the chronic form with a probability of 75.57%. The use of classic MRE layered bowel wall enhancement and a DWI-based ADC metric eliminates the main shortcomings of both approaches., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Termedia.)
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- 2022
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8. L-Carnitine Combined with Leucine Supplementation Does Not Improve the Effectiveness of Progressive Resistance Training in Healthy Aged Women.
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Sawicka AK, Jaworska J, Brzeska B, Sabisz A, Samborowska E, Radkiewicz M, Szurowska E, Winklewski PJ, Szarmach A, and Olek RA
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- Female, Humans, Decorin metabolism, Dietary Supplements, Insulin-Like Growth Factor I, Muscle Strength physiology, Muscle, Skeletal, Myostatin metabolism, Tartrates pharmacology, Middle Aged, Aged, Carnitine pharmacology, Leucine pharmacology, Resistance Training
- Abstract
Objectives: To evaluate the effect of L-carnitine (LC) in combination with leucine supplementation on muscle strength and muscle hypertrophy in aged women participating in a resistance exercise training (RET) program., Design/setting/participants: Thirty-seven out of sixty (38.3% dropout) healthy women aged 60-75 years (mean 67.6 ± 0.7 years) completed the intervention in one of three groups. One of the supplemented groups received 1 g of L-carnitine-L-tartrate in combination with 3 g of L-leucine per day (LC+L group; n = 12), and the second supplemented group received 4 g of L-leucine per day (L group; n = 13). The control group (CON group; n = 12) received no supplementation., Intervention: All three groups completed the same RET protocol involving exercise sessions twice per week for 24 weeks., Measurements: Before and after the experiment, participants performed isometric and isokinetic muscle strength testing on the Biodex dynamometer. The cross-sectional areas of the major knee extensors and total thigh muscles were assessed using magnetic resonance imaging. Fasting serum levels of insulin-like growth factor-1 (IGF-1), myostatin and decorin, and plasma levels of total carnitine (TC) and trimethylamine-N-oxide (TMAO) levels were measured., Results: The 24-week RET significantly increased muscle strength and muscle volume, but the group and time interactions were not significant for the muscle variables analyzed. Plasma total carnitine increased only in the LC+L group (p = 0.009). LC supplementation also caused a significant increase in plasma TMAO, which was higher after the intervention in the LC+L group than in the L (p < 0.001), and CON (p = 0.005) groups. The intervention did not change plasma TMAO concentration in the L (p = 0.959) and CON (p = 0.866) groups. After the intervention serum decorin level was higher than before in both supplemented groups combined (p = 0.012), still not significantly different to post intervention CON (p = 0.231). No changes in serum IGF-1 and myostatin concentrations and no links between the changes in blood markers and muscle function or muscle volume were observed., Conclusions: LC combined with leucine or leucine alone does not appear to improve the effectiveness of RET.
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- 2022
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9. Substances of abuse and the blood brain barrier: Interactions with physical exercise.
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Małkiewicz MA, Małecki A, Toborek M, Szarmach A, and Winklewski PJ
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- Exercise, Humans, Blood-Brain Barrier, Substance-Related Disorders
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Substance use disorders pose a common medical, social and financial problem. Among the pathomechanisms of substance use disorders, the disruption and increased permeability of the blood-brain barrier has been recently revealed. Physical exercise appears to be a relatively inexpensive and feasible way to implement behavioral therapy counteracting the blood-brain barrier impairment. Concomitantly, there are also studies supporting a potential protective role of selected substances of abuse in maintaining the blood-brain barrier integrity. In this review, we aim to provide a summary on the modulatory influence of physical exercise, a non-pharmacological intervention, on the blood-brain barrier alterations caused by substances of abuse. Further studies are needed to understand the precise mechanisms that underlie various effects of physical exercise in substance use disorders., (Copyright © 2020. Published by Elsevier Ltd.)
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- 2020
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10. A Pilot Study on the Effects of l-Carnitine and Trimethylamine-N-Oxide on Platelet Mitochondrial DNA Methylation and CVD Biomarkers in Aged Women.
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Bordoni L, Sawicka AK, Szarmach A, Winklewski PJ, Olek RA, and Gabbianelli R
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- Aged, Atherosclerosis drug therapy, Blood Platelets metabolism, Cardiovascular System drug effects, Cardiovascular System metabolism, Dietary Supplements, Female, Humans, Lipid Metabolism drug effects, Middle Aged, Mitochondria drug effects, Mitochondria metabolism, Pilot Projects, Atherosclerosis metabolism, Biomarkers metabolism, Blood Platelets drug effects, Carnitine pharmacology, DNA Methylation drug effects, DNA, Mitochondrial drug effects, Methylamines pharmacology, Oxides pharmacology
- Abstract
l-carnitine supplementation has been used for cardiovascular health protection for a long time. Recently, trimethylamine-N-oxide (TMAO), which is an end product of l-carnitine metabolism via the activity of microbiota, has been identified as a cardiovascular disease (CVD) biomarker. The aim of this study was to assess the effect of 6 months of l-carnitine supplementation in a group of aged women engaged in a regular physical training. Platelet mitochondrial DNA methylation, an emerging and innovative biomarker, lipid profile and TMAO levels have been measured. TMAO increased after l-carnitine supplementation (before 344.3 ± 129.8 ng/mL vs. after 2216.8 ± 1869.0 ng/mL; n = 9; paired t-test, p = 0.02). No significant effects on TMAO were exerted by training alone ( n = 9) or by l-leucine supplementation ( n = 12). TMAO levels after 6 months of l-carnitine supplementation were associated with higher low-density lipoprotein-cholesterol (LDL-c) (Spearman Rho = 0.518, p = 0.003) and total cholesterol (TC) (Spearman Rho = 0.407, p = 0.026) levels. l-carnitine supplementation increased D-loop methylation in platelets (+6.63%; paired t-test, p = 0.005). D-loop methylation was not directly correlated to the TMAO augmentation observed in the supplemented group, but its increase inversely correlated with TC (Pearson coefficient = -0.529, p = 0.029) and LDL-c (Pearson coefficient = -0.439, p = 0.048). This evidence supports the hypothesis that the correlation between l-carnitine, TMAO and atherosclerosis might be more complex than already postulated, and the alteration of mitochondrial DNA (mtDNA) methylation in platelets could be involved in the pathogenesis of this multifactorial disease.
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- 2020
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11. Computed tomography indicators of cerebral microperfusion improve long term after carotid stenting in symptomatic patients.
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Winklewski PJ, Kaszubowski M, Halena G, Sabisz A, Chwojnicki K, Dzierżanowski J, Piskunowicz M, Kurhaluk N, Szurowska E, and Szarmach A
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- Aged, Aged, 80 and over, Cerebrovascular Circulation, Female, Follow-Up Studies, Humans, Male, Middle Aged, Radiation Dosage, Treatment Outcome, Blood Vessel Prosthesis Implantation, Brain blood supply, Carotid Artery, Internal pathology, Carotid Stenosis surgery, Microcirculation, Stents, Tomography, X-Ray Computed methods
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Objectives: We tested the hypothesis that computed tomography (CT) perfusion markers of cerebral microcirculation would improve 36 months after internal carotid artery stenting for symptomatic carotid stenosis while results obtained 6-8 weeks after the stenting procedure would yield a predictive value., Methods: We recruited consecutive eligible patients with >70% symptomatic carotid stenosis with a complete circle of Willis and normal vertebral arteries to the observational cohort study. We detected changes in the cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP) and permeability surface area-product (PS) before and after carotid stenting. We have also compared the absolute differences in the ipsilateral and contralateral CT perfusion markers before and after stenting. The search for regression models of "36 months after stenting" results was based on a stepwise analysis with bidirectional elimination method., Results: A total of 34 patients completed the 36 months follow-up (15 females, mean age of 69.68±S.D. 7.61 years). At 36 months after stenting, the absolute values for CT perfusion markers had improved: CBF (ipsilateral: +7.76%, contralateral: +0.95%); CBV (ipsilateral: +5.13%, contralateral: +3.00%); MTT (ipsilateral: -12.90%; contralateral: -5.63%); TTP (ipsilateral: -2.10%, contralateral: -4.73%) and PS (ipsilateral: -35.21%, contralateral: -35.45%). MTT assessed 6-8 weeks after stenting predicted the MTT value 36 months after stenting (ipsilateral: R2=0.867, contralateral R2=0.688)., Conclusions: We have demonstrated improvements in CT perfusion markers of cerebral microcirculation health that persist for at least 3 years after carotid artery stenting in symptomatic patients. MTT assessed 6-8 weeks after stenting yields a predictive value.
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- 2019
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12. Cardiac Involvement in Systemic Sclerosis: Diagnostic Tools and Evaluation Methods.
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Smolenska Z, Barraclough R, Dorniak K, Szarmach A, and Zdrojewski Z
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- Diagnostic Imaging methods, Global Health, Humans, Incidence, Prognosis, Heart Diseases diagnosis, Heart Diseases epidemiology, Heart Diseases etiology, Scleroderma, Systemic complications
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The heart is one of the major organs commonly involved in systemic sclerosis (SSc). Myocardial fibrosis has been identified in a high percentage of these patients. Most SSc patients with cardiac involvement (CI) are subclinical, especially early on in the course of their disease. To accurately identify CI and improve diagnosis and treatment, imaging techniques should be implemented on a regular basis following diagnosis. In this review, we discuss the up-to-date pathophysiologic basis of CI, the cardiac manifestations, and the diagnostic methods that have been published in the literature. Recent studies have shown that tissue Doppler imaging is a promising evaluation technique in the bedside detection of CI. Cardiovascular magnetic resonance is an operator-independent method used for detecting SSc CI. It is an especially useful tool in the early stages of the disease when patients may be asymptomatic. At present, it is the most promising imaging technique for the diagnosis, follow-up, and response to therapy in clinical practice.
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- 2019
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13. Blood-brain barrier permeability and physical exercise.
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Małkiewicz MA, Szarmach A, Sabisz A, Cubała WJ, Szurowska E, and Winklewski PJ
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- Animals, Humans, Blood-Brain Barrier metabolism, Exercise physiology, Physical Conditioning, Animal methods
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In this narrative review, a theoretical framework on the crosstalk between physical exercise and blood-brain barrier (BBB) permeability is presented. We discuss the influence of physical activity on the factors affecting BBB permeability such as systemic inflammation, the brain renin-angiotensin and noradrenergic systems, central autonomic function and the kynurenine pathway. The positive role of exercise in multiple sclerosis and Alzheimer's disease is described. Finally, the potential role of conditioning as well as the effect of exercise on BBB tight junctions is outlined. There is a body of evidence that regular physical exercise diminishes BBB permeability as it reinforces antioxidative capacity, reduces oxidative stress and has anti-inflammatory effects. It improves endothelial function and might increase the density of brain capillaries. Thus, physical training can be emphasised as a component of prevention programs developed for patients to minimise the risk of the onset of neuroinflammatory diseases as well as an augmentation of existing treatment. Unfortunately, despite a sound theoretical background, it remains unclear as to whether exercise training is effective in modulating BBB permeability in several specific diseases. Further research is needed as the impact of exercise is yet to be fully elucidated.
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- 2019
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14. The "Optimum Volume" of Acrylic Cement Filling for Treating Vertebral Compression Fractures: A Morphometric Study of Thoracolumbar Vertebrae.
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Dzierżanowski J, Winklewski PJ, Skotarczak M, Baczkowska-Waliszewska Z, Szmuda T, Zdanowski S, Radkowski M, Łuczkiewicz P, Czapiewski P, Słoniewski P, Szurowska E, Demkow U, and Szarmach A
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- Adult, Humans, Spine diagnostic imaging, Tomography, X-Ray Computed, Treatment Outcome, Bone Cements, Fractures, Compression surgery, Spinal Fractures surgery, Vertebroplasty
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Percutaneous vertebroplasty is a treatment option in vertebral compression fractures (VCF). The aim of the study was to propose the mathematical calculation of the "optimum volume" of acrylic cement filling of the vertebral body, depending on the severity of a fracture. Two hundred computed tomography (CT) scans of vertebral columns in healthy adult Caucasians were analyzed. Vertebral body width (VBW), vertebral body depth (VBD), vertebral body height (VBH), and vertebral body volume (VBV) were measured. The "optimum volume" of cement injections in mild (25% collapse) and moderate (40% collapse) VCF were calculated. We found that moving caudally from Th
11 to L2 , the mean values of the examined parameters increased: VBH from 22.6 to 26.0 mm, VBW from 34.0 to 39.5 mm, VBD from 28.1 to 30.9 mm, and VBV from 17.1 to 24.8 cm3 . The calculated hypothetical "optimum volume" of cement injection increased from 7.4 to 10.0 cm3 in mild VCF and from 5.9 to 7.8 cm3 in moderate VCF, with some variability depending on the vertebral level and gender. These values are akin to those present in other past studies. We conclude that morphometric measurements, based on CT images, are a reliable source of practical anatomical savvy, which may be of help in spine surgery.- Published
- 2019
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15. Morphometric Analysis of the Lumbar Vertebrae Concerning the Optimal Screw Selection for Transpedicular Stabilization.
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Dzierżanowski J, Skotarczyk M, Baczkowska-Waliszewska Z, Krakowiak M, Radkowski M, Łuczkiewicz P, Czapiewski P, Szmuda T, Słoniewski P, Szurowska E, Winklewski PJ, Demkow U, and Szarmach A
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- Adult, Aged, Female, Humans, Male, Middle Aged, Tomography, X-Ray Computed, Bone Screws, Lumbar Vertebrae anatomy & histology, Spinal Fusion
- Abstract
Transpedicular stabilization is a frequently used spinal surgery for fractures, degenerative changes, or neoplastic processes. Improper screw fixation may cause substantial vascular or neurological complications. This study seeks to define detailed morphometric measurements of the pedicle (height, width, and surface area) in the aspects of screw length and girth selection and the trajectory of its implantation, i.e., sagittal and transverse angle of placement. The study was based on CT examinations of 100 Caucasian patients (51 women and 49 men) aged 27-75 with no anatomical, degenerative, or post-traumatic spine changes. The results were stratified by gender and body side, and they were counter compared with the available literature database. Pedicle height decreased from L1 to L4, ranging from 15.9 to 13.3 mm. Pedicle width increased from L1 to L5, extending from 6.1 to 13.2 mm. Pedicle surface area increased from L1 to L5, ranging from 63 to 140 mm
2 . Distance from the point of entry into the pedicle to the anterior surface of the vertebral body, defining the maximum length of a transpedicular screw, varied from 54.0 to 50.2 mm. Variations concerning body sides were inappreciable. A transverse angle of screw trajectory extended from 20° to 32°, shifting caudally from L1 to L5, with statistical differences in the L3-L5 segments. A sagittal angle varied from 10° to 12°, without such definite relations. We conclude that the L1 and L2 segments display the most distinct morphometric similarities, while the greatest differences, in both genders, are noted for L3, L4, and L5. The findings enable the recommendation of the following screw diameters: 4 mm for L1-L2, 5 mm for L3, 6 mm for L4-L5, and the length of 50 mm. We believe the study has extended clinical knowledge on lumbar spine morphometry, essential in the training physicians engaged in transpedicular stabilization.- Published
- 2019
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16. Relative Cerebral Blood Transit Time Decline and Neurological Improvement in Patients After Internal Carotid Artery Stenting.
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Szarmach A, Małkiewicz MA, Zdun-Ryżewska A, Halena G, Radkowski M, Dzierżanowski J, Chwojnicki K, Muc A, Damaszko T, Łyźniak P, Piskunowicz M, Szurowska E, Demkow U, and Winklewski PJ
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- Brain blood supply, Brain diagnostic imaging, Female, Humans, Male, Time, Tomography, X-Ray Computed, Carotid Artery, Internal diagnostic imaging, Carotid Artery, Internal surgery, Carotid Stenosis diagnostic imaging, Carotid Stenosis surgery, Cerebrovascular Circulation, Stents standards
- Abstract
In this study we hypothesized that the alleviation of neurological symptoms long after internal carotid artery (ICA) stenting may be related to sustained improvement of cerebral perfusion. Thirty-four subjects (F/M; 15/19) with >70% stenosis of a single internal carotid artery and neurological symptoms, who underwent a carotid artery stenting procedure, were studied. Brain computed tomography perfusion (CTP) imaging was performed before and 3 years after ICA stenting. The following relative variables were compared: cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), time to peak (rTTP), and permeability surface area product (rPS). A survey also was conducted to compare the patients' clinical symptoms. Overall, we found that a trend toward rMTT decline was the only persisting change after ICA stenting. We then stratified the patients into the subgroups of <2%, 2-5%, and > 5% rMTT decline and found that those with a rMTT decline >2% reported a prominent reduction in subjective clinical symptoms such as headache, dizziness, tinnitus, blurred vision, transient blindness, a sense of gravity of the head, and pain in the eyeballs. We conclude that a shortened mean rMTT, likely reflecting improved cerebral microcirculation, underlies the improvement of neurological symptoms in patients with ICA stenosis.
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- 2019
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17. Effects of melatonin on low-dose lipopolysaccharide-induced oxidative stress in mouse liver, muscle, and kidney.
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Kurhaluk N, Szarmach A, Zaitseva OV, Sliuta A, Kyriienko S, and Winklewski PJ
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- Animals, Kidney drug effects, Kidney metabolism, Lipopolysaccharides administration & dosage, Lipopolysaccharides toxicity, Liver drug effects, Liver metabolism, Male, Mice, Mice, Inbred BALB C, Models, Animal, Muscle, Skeletal drug effects, Muscle, Skeletal metabolism, Antioxidants pharmacology, Lipid Peroxidation drug effects, Melatonin pharmacology, Oxidative Stress drug effects
- Abstract
Lipopolysaccharide (LPS) administration in an in vivo experimental mice model causes oxidative damage in the liver, muscle, and kidney. We aimed to determine specific mechanisms underlying melatonin's antioxidant protective role. Assays were carried out in quadruplicate in the control, melatonin (10 mg/kg, 10 days), acute LPS administration (once 150 μg), and LPS + melatonin groups. LPS stimulated lipid peroxidation processes (dienes and malondialdehyde) and antioxidant enzyme concentrations (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) were assessed in all investigated tissues. Protein oxidation processes (measured as aldehyde and kenotic carbonyl protein derivatives) were enhanced by LPS in the kidney and liver but not in muscle. Melatonin reversed LPS-induced changes, with the exception of muscle protein oxidation. LPS-induced oxidative stress resulted in augmented early-stage diene conjugated and end-stage malondialdehyde lipid peroxidation processes and affected antioxidant activity in liver, kidney, and muscle tissues. LPS activated protein oxidation processes in the kidney and liver. Melatonin ameliorated oxidative damage in the liver, kidney, and partially in the muscle. Melatonin modulates oxidative stress-induced states. Potential synergism between melatonin and systemic inflammation in terms of oxidative modification of muscle proteins needs to be clarified in further studies.
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- 2018
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18. Central sympathetic nervous system reinforcement in obstructive sleep apnoea.
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Wszedybyl-Winklewska M, Wolf J, Szarmach A, Winklewski PJ, Szurowska E, and Narkiewicz K
- Subjects
- Baroreflex physiology, Blood Pressure physiology, Brain physiopathology, Cardiovascular System, Heart Rate physiology, Humans, Cerebrovascular Circulation physiology, Sleep Apnea, Obstructive physiopathology, Sympathetic Nervous System physiopathology
- Abstract
The available studies on cerebrovascular reactivity and cerebral oxygenation in obstructive sleep apnoea (OSA) patients brought conflicting results, yet the overall evidence suggests that resting state cerebral perfusion is diminished in these patients. Interestingly, in a group of healthy professional breath-hold divers who are exercising very long apnoeas - episodes corresponding to the ones observed in patients with OSA - demonstrated that cerebral oxygenation may remain stable at the expense of extreme sympathetic nervous system (SNS) activation. In the present review we address several mechanisms that could potentially explain these discrepancies. We focus in depth on mechanisms of central SNS reinforcement in OSA including dysfunctional baroreflex response, and inflammatory processes within the brain centres controlling the cardiovascular system. Additionally, novel insights into physiology of cerebral blood flow regulation are proposed, including the role of short-term blood pressure changes, heart rate fluctuations and baroreflex alterations. Finally, a potential role of increased blood flow pulsatility in cerebrospinal fluid circulation changes and its influence on SNS drive is highlighted. The presented review provides insights into how sympathetic nervous system reinforcement in OSA promotes maladaptive mechanisms that could alter cerebral perfusion regulation, and result in functional and structural cerebral changes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
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- 2018
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19. Understanding the Physiopathology Behind Axial and Radial Diffusivity Changes-What Do We Know?
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Winklewski PJ, Sabisz A, Naumczyk P, Jodzio K, Szurowska E, and Szarmach A
- Abstract
The use of the diffusion tensor imaging (DTI) is rapidly growing in the neuroimaging field. Nevertheless, rigorously performed quantitative validation of DTI pathologic metrics remains very limited owing to the difficulty in co-registering quantitative histology findings with magnetic resonance imaging. The aim of this review is to summarize the existing state-of-the-art knowledge with respect to axial (λ
║ ) and radial (λ┴ ) diffusivity as DTI markers of axonal and myelin damage, respectively. First, we provide technical background for DTI and briefly discuss the specific organization of white matter in bundles of axonal fibers running in parallel; this is the natural target for imaging based on diffusion anisotropy. Second, we discuss the four seminal studies that paved the way for considering axial (λ║ ) and radial (λ┴ ) diffusivity as potential in vivo surrogate markers of axonal and myelin damage, respectively. Then, we present difficulties in interpreting axial (λ║ ) and radial (λ┴ ) diffusivity in clinical conditions associated with inflammation, edema, and white matter fiber crossing. Finally, future directions are highlighted. In summary, DTI can reveal strategic information with respect to white matter tracts, disconnection mechanisms, and related symptoms. Axial (λ║ ) and radial (λ┴ ) diffusivity seem to provide quite consistent information in healthy subjects, and in pathological conditions with limited edema and inflammatory changes. DTI remains one of the most promising non-invasive diagnostic tools in medicine.- Published
- 2018
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20. Regional resting state perfusion variability and delayed cerebrovascular uniform reactivity in subjects with chronic carotid artery stenosis.
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Szarmach A, Kaszubowski M, Sabisz A, Frydrychowski AF, Halena G, Piskunowicz M, Dzierzanowski J, Studniarek M, Szurowska E, and Winklewski PJ
- Subjects
- Acetazolamide pharmacology, Aged, Brain Stem drug effects, Chronic Disease, Female, Gray Matter drug effects, Humans, Male, Middle Aged, White Matter drug effects, Carotid Stenosis physiopathology, Cerebrovascular Circulation drug effects
- Abstract
The aim of this study was to assess regional perfusion at baseline and regional cerebrovascular resistance (CVR) to delayed acetazolamide challenge in subjects with chronic carotid artery stenosis. Sixteen patients (ten males) aged 70.94±7.71 with carotid artery stenosis ≥ 90% on the ipsilateral side and ≤ 50% on the contralateral side were enrolled into the study. In all patients, two computed tomography perfusion examinations were carried out; the first was performed before acetazolamide administration and the second 60 minutes after injection. The differences between mean values were examined by paired two-sample t-test and alternative nonparametric Wilcoxon's test. Normality assumption was examined using W Shapiro-Wilk test. The lowest resting-state cerebral blood flow (CBF) was observed in white matter (ipsilateral side: 18.4±6.2; contralateral side: 19.3±6.6) and brainstem (ipsilateral side: 27.8±8.5; contralateral side: 29.1±10.8). Grey matter (cerebral cortex) resting state CBF was below the normal value for subjects of this age: frontal lobe - ipsilateral side: 30.4±7.0, contralateral side: 33.7±7.1; parietal lobe - ipsilateral side: 36.4±11.3, contralateral side: 42.7±9.9; temporal lobe - ipsilateral side: 32.5±8.6, contralateral side: 39.4±10.8; occipital lobe - ipsilateral side: 24.0±6.0, contralateral side: 26.4±6.6). The highest resting state CBF was observed in the insula (ipsilateral side: 49.2±17.4; contralateral side: 55.3±18.4). A relatively high resting state CBF was also recorded in the thalamus (ipsilateral side: 39.7±16.9; contralateral side: 41.7±14.1) and cerebellum (ipsilateral side: 41.4±12.2; contralateral side: 38.1±11.3). The highest CVR was observed in temporal lobe cortex (ipsilateral side: +27.1%; contralateral side: +26.1%) and cerebellum (ipsilateral side: +27.0%; contralateral side: +34.6%). The lowest CVR was recorded in brain stem (ipsilateral side: +20.2%; contralateral side: +22.2%) and white matter (ipsilateral side: +18.1%; contralateral side: +18.3%). All CBF values were provided in milliliters of blood per minute per 100 g of brain tissue (ml/100g/min). Resting state circulation in subjects with carotid artery stenosis is low in all analysed structures with the exception of insula and cerebellum. Acetazolamide challenge yields relatively uniform response in both hemispheres in the investigated population. Grey matter is more reactive to acetazolamide challenge than white matter or brainstem.
- Published
- 2018
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21. Oscillations of Subarachnoid Space Width as a Potential Marker of Cerebrospinal Fluid Pulsatility.
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Gruszecki M, Nuckowska MK, Szarmach A, Radkowski M, Szalewska D, Waskow M, Szurowska E, Frydrychowski AF, Demkow U, and Winklewski PJ
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- Humans, Cerebrospinal Fluid physiology, Pulsatile Flow physiology, Subarachnoid Space physiology
- Abstract
In the cerebrospinal fluid (CSF) circulation, two components can be distinguished: bulk flow (circulation) and pulsatile flow (back and forth motion). CSF pulsatile flow is generated by both cardiac and respiratory cycles. Recent years have seen increased interest in cardiac- and respiratory-driven CSF pulsatility as an important component of cerebral homeostasis. CSF pulsatility is affected by cerebral arterial inflow and jugular outflow and potentially linked to white matter abnormalities in various diseases, such as multiple sclerosis or hypertension. In this review, we discuss the physiological mechanisms associated with CSF pulsation and its clinical significance. Finally, we explain the concept of using the oscillations of subarachnoid space width as a surrogate for CSF pulsatility.
- Published
- 2018
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22. Cognitive Predictors of Cortical Thickness in Healthy Aging.
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Naumczyk P, Sawicka AK, Brzeska B, Sabisz A, Jodzio K, Radkowski M, Czachowska K, Winklewski PJ, Finc K, Szurowska E, Demkow U, and Szarmach A
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- Aged, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Neuropsychological Tests, Brain diagnostic imaging, Cognition, Healthy Aging
- Abstract
This study seeks to define the role of predictive values of the motor speed, inhibition control, and fluid and crystallized intelligence in estimating the cortical thickness in healthy elderly. Forty-six older healthy subjects (37 women, 9 men) over 60 years of age were included in the study. The participants were examined on 3.0 T MRI scanners. The protocol included standard anatomical sequences, to exclude brain pathology, and a high-resolution T1-weighted sequence used to estimate the cortical thickness. The neuropsychological protocol included fluid intelligence assessment (Raven Progressive Matrices), crystalized intelligence assessment (information or vocabulary subtest of the Wechsler Adult Intelligence Scale-Revised (WAIS-R)), and executive functioning (Color Traits Test). The findings unraveled several interdependencies. The higher the intelligence, the thicker was the grey matter in nine regions of both hemispheres, but also some paradoxical reversed associations were found in four areas; all of them were localized along different sections of the cingulate gyrus in both hemispheres. An inverse association was found between crystallized intelligence and the thickness of the pars opecularis of the right hemisphere. The better the executive functioning, the thicker was the grey matter of a given region. The better the motor performance, the thicker was the grey matter of the rostral middle frontal area of the left hemisphere and the lingual gyrus of both hemispheres. In conclusion, the associations unraveled demonstrate that the neural mechanisms underlying healthy aging are complex and heterogenic across different cognitive domains and neuroanatomical regions. No brain aging theory seems to provide a suitable interpretative framework for all the results. A novel, more integrative approach to the brain aging should be considered.
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- 2018
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23. Carotid Artery Stenting and Blood-Brain Barrier Permeability in Subjects with Chronic Carotid Artery Stenosis.
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Szarmach A, Halena G, Kaszubowski M, Piskunowicz M, Studniarek M, Lass P, Szurowska E, and Winklewski PJ
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- Aged, Blood-Brain Barrier diagnostic imaging, Capillary Permeability, Carotid Stenosis metabolism, Carotid Stenosis pathology, Cerebrovascular Circulation, Female, Humans, Male, Middle Aged, Vascular Surgical Procedures instrumentation, Blood-Brain Barrier metabolism, Carotid Stenosis surgery, Stents adverse effects, Vascular Surgical Procedures adverse effects
- Abstract
Failure of the blood-brain barrier (BBB) is a critical event in the development and progression of diseases such as acute ischemic stroke, chronic ischemia or small vessels disease that affect the central nervous system. It is not known whether BBB breakdown in subjects with chronic carotid artery stenosis can be restrained with postoperative recovery of cerebral perfusion. The aim of the study was to assess the short-term effect of internal carotid artery stenting on basic perfusion parameters and permeability surface area-product (PS) in such a population. Forty subjects (23 males) with stenosis of >70% within a single internal carotid artery and neurological symptoms who underwent a carotid artery stenting procedure were investigated. Differences in the following computed tomography perfusion (CTP) parameters were compared before and after surgery: global cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP) and PS. PS acquired by CTP is used to measure the permeability of the BBB to contrast material. In all baseline cases, the CBF and CBV values were low, while MTT and TTP were high on both the ipsi- and contralateral sides compared to reference values. PS was approximately twice the normal value. CBF was higher (+6.14%), while MTT was lower (-9.34%) on the contralateral than on the ipsilateral side. All perfusion parameters improved after stenting on both the ipsilateral (CBF +22.66%; CBV +18.98%; MTT -16.09%, TTP -7.62%) and contralateral (CBF +22.27%, CBV +19.72%, MTT -14.65%, TTP -7.46%) sides. PS decreased by almost half: ipsilateral -48.11%, contralateral -45.19%. The decline in BBB permeability was symmetrical on the ipsi- and contralateral sides to the stenosis. Augmented BBB permeability can be controlled by surgical intervention in humans.
- Published
- 2017
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24. Morphometric evaluation of the delayed cerebral arteries response to acetazolamide test in patients with chronic carotid artery stenosis using computed tomography angiography.
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Szarmach A, Winklewski PJ, Halena G, Kaszubowski M, Dzierżanowski J, Piskunowicz M, Szurowska E, and Frydrychowski AF
- Subjects
- Adult, Aged, Carotid Stenosis diagnostic imaging, Carotid Stenosis physiopathology, Female, Humans, Male, Middle Aged, Acetazolamide administration & dosage, Carotid Artery, Internal diagnostic imaging, Carotid Artery, Internal physiopathology, Cerebral Arteries diagnostic imaging, Cerebral Arteries physiopathology, Computed Tomography Angiography
- Abstract
Background: The evidence accumulates that the response to acetazolamide test is delayed on the ipsilateral side to stenosis. However, the effect of acetazolamide beyond 30 min after acetazolamide administration remains unknown. The aim of this study was to assess the diameters of anterior cerebral arteries (ACAs), middle cerebral arteries (MCAs) and posterior cerebral arteries (PCAs) before and 60 min after the acetazolamide test., Materials and Methods: Seventeen patients with carotid artery stenosis ≥ 90% on the ipsilateral side and ≤ 50% on the contralateral side were enrolled into the study. Diagnosis was based on ultrasonography examination and was confirmed using digital subtractive angiography. In all patients, two computed tomography angiography examinations were carried out; the first was performed before the acetazolamide administration, while the second one was carried out 60 min after injections., Results: In response to the acetazolamide test: PCA diameter diminished in both ipsi- and contra-lateral side to stenosis (from 1.31 to 1.24 mm and from 1.23 to 1.15 mm, respectively), ACA and MCA decreased in the contralateral side to the stenosis (from 1.33 to 1.26 mm and from 2.75 to 2.66 mm, respectively), ACA and MCA increased in the ipsilateral side to the stenosis (from 1.29 to 1.46 mm and from 2.77 to 2.96 mm, respectively). All changes were statistically significant., Conclusions: There were significant differences in reactivity to acetazolamide challenge between the internal carotid artery (ICA) and vertebrobasilar circulation in patients suffering from chronic carotid artery stenosis. Within the ICA territory, ACA and MCA responses vary in the affected and not affected side.
- Published
- 2017
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25. Intracranial region of the vertebral artery: morphometric study in the context of clinical usefulness.
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Dzierżanowski J, Szarmach A, Baścik B, Czapiewski P, Muc A, Piskunowicz M, Krakowiak M, Szmuda T, Słoniewski P, Szurowska E, and Winklewski PJ
- Subjects
- Adult, Aged, Aged, 80 and over, Angiography, Digital Subtraction, Basilar Artery abnormalities, Basilar Artery pathology, Female, Humans, Imaging, Three-Dimensional, Male, Middle Aged, Vertebral Artery abnormalities, Vertebral Artery diagnostic imaging, Vertebrobasilar Insufficiency diagnostic imaging, Vertebrobasilar Insufficiency pathology, Young Adult, Vertebral Artery pathology
- Abstract
Background: The aim of this study was to analyse the morphometry of the intracranial segment of the vertebral artery in the context of clinical usefulness. The results were compared with published data available in full-text archived medical journals., Materials and Methods: More than 100 digital subtraction angiography (DSA) and 3-dimensional (3D) angio-computed tomography (CT) examinations were used to measure the following parameters: the whole and partial length of V4 in characteristic anatomical points, the diameter in three places (on the level of foramen magnum, in point of exit to the posterior inferior cerebellar artery, and in the vertebro-basilar junction), the angle of connection to the vertebral arteries, and all anatomical variations including fenestration, duplication, dolichoectasia or absent artery., Results: The left V4 section was predominant over the right artery, which is manifested by length, width, cases of ectasia and fewer cases of hypoplasia. The incidences of V4 ectasia were identified more often than those documented in the accessible literature, and they were found in the natural location of formation of saccular aneurysms., Conclusions: The presented knowledge of anatomical variation and abnormali-ties of vertebral circulation can improve the accuracy and "safety" of the surgical procedures in this region, help to determine the range of surgical approach and avoid associated complications. The radiological examinations using 3D CT, DSA reveal unlimited observation of anatomical structures in contrast to studies based on cadavers, and can complement the morphometry in anatomical preparations.
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- 2017
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26. Comparison of voiding cystourethrography and urosonography with second-generation contrast agents in simultaneous prospective study.
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Piskunowicz M, Świętoń D, Rybczyńska D, Czarniak P, Szarmach A, Kaszubowski M, and Szurowska E
- Abstract
Background: The invasiveness and exposure to radiation in voiding cystourethrography led to the introduction of alternative methods of diagnosis of vesicoureteral reflux, including contrast enhanced voiding urosonography. While there is a limited number of studies comparing these methods using new generation ultrasound contrast agents, none of them compared both methods simultaneously. This study is aimed at assessing agreement between contrast enhanced voiding urosonography with second-generation ultrasound contrast agents and voiding cystourethrography., Methods: From April 2013 to May 2014, 83 children (37 female and 46 male), mean age 3.5 years, age range from 1 month to 17.5 years, underwent prospective simultaneous assessment by contrast enhanced voiding urosonography and voiding cystourethrography, with a total of 166 uretero-renal units evaluated., Results: The sensitivity of voiding cystourethrography and contrast enhanced voiding urosonography were comparable, amounting to 88%, however, neither reached 100% for the entire studied population. The negative predictive value of voiding urosonography and voiding cystourethrography was 97%, and there was no difference between both methods., Conclusion: Voiding cystourethrography and contrast enhanced voiding urosonography are comparable methods in diagnosis of vesicoureteral reflux, and can be performed alternatively. However, some limitations of contrast enhanced voiding urosonography must be remembered., Competing Interests: The study was financed from the means of the National Science Centre, granted on the basis of decision No. DEC-2012/05/B/NZ5/01554. Authors do not report any financial or personal connections with other persons or organizations, which might negatively affect the contents of this publication and/or claim authorship rights to this publication.
- Published
- 2016
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27. Perfusion computed tomography: 4 cm versus 8 cm coverage size in subjects with chronic carotid artery stenosis.
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Szarmach A, Halena G, Kaszubowski M, Piskunowicz M, Szurowska E, Frydrychowski AF, and Winklewski PJ
- Subjects
- Aged, Cerebrovascular Circulation, Chronic Disease, Female, Humans, Male, Ultrasonography, Doppler, Transcranial, Carotid Artery, Internal diagnostic imaging, Carotid Stenosis diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
Objective: The impact of coverage size on global cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak (TTP) parameters has not been investigated in patients with chronic carotid artery stenosis., Methods: 63 patients with stenosis of >70% within a single internal carotid artery and neurological symptoms were randomly assigned to two well-matched groups. Differences in CT perfusion scan over a 4 cm or 8 cm range of the brain were compared between the two groups., Results: The CBF and CBV values were higher in the 4 cm coverage size than in the 8 cm coverage size (by 14.7 and 10.7% on the ipsilateral side and 17.2 and 7.8% on the contralateral side, respectively; all p < 0.001). The MTT value was higher in the 4 cm coverage size than in the 8 cm coverage size on the ipsilateral side (9.6%; p < 0.001). There was no difference between MTT values in the contralateral size. There were no differences between TTP values on the ipsilateral and contralateral sides. The relative indices rMTT and rTTP were higher in the 4 cm coverage size than in the 8 cm coverage size (8.2%, p < 0.001, and 1.1%, p < 0.005, respectively)., Conclusion: Absolute CBF and CBV values and relative rMTT and rTTP indices in patients with low CBF and low CBV are highly dependent on coverage size. We recommend using a 4 cm coverage size to assess global cerebral perfusion parameters owing to better accuracy and quicker post-processing., Advances in Knowledge: To the best of our knowledge, this is the first article to compare the influence of 4 cm vs 8 cm coverage size on cerebral perfusion parameters such as CBF, CBV, MTT and TTP in subjects with chronic carotid artery stenosis.
- Published
- 2016
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28. Assessment of the Relationship between the Shape of the Lateral Meniscus and the Risk of Extrusion Based on MRI Examination of the Knee Joint.
- Author
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Szarmach A, Luczkiewicz P, Skotarczak M, Kaszubowski M, Winklewski PJ, Dzierzanowski J, Piskunowicz M, Szurowska E, and Baczkowski B
- Subjects
- Adolescent, Adult, Biomechanical Phenomena, Female, Humans, Knee Joint physiopathology, Logistic Models, Magnetic Resonance Imaging, Male, Menisci, Tibial pathology, Menisci, Tibial physiopathology, Middle Aged, Models, Biological, Risk Factors, Tibial Meniscus Injuries etiology, Young Adult, Knee Joint diagnostic imaging, Knee Joint pathology, Menisci, Tibial diagnostic imaging, Tibial Meniscus Injuries diagnostic imaging, Tibial Meniscus Injuries pathology
- Abstract
Background: Meniscus extrusion is a serious and relatively frequent clinical problem. For this reason the role of different risk factors for this pathology is still the subject of debate. The goal of this study was to verify the results of previous theoretical work, based on the mathematical models, regarding a relationship between the cross-section shape of the meniscus and the risk of its extrusion., Materials and Methods: Knee MRI examination was performed in 77 subjects (43 men and 34 women), mean age 34.99 years (range: 18-49 years), complaining of knee pain. Patients with osteoarthritic changes (grade 3 and 4 to Kellgren classification), varus or valgus deformity and past injuries of the knee were excluded from the study. A 3-Tesla MR device was used to study the relationship between the shape of the lateral meniscus (using slope angle, meniscus-cartilage height and meniscus-bone angle) and the risk of extrusion., Results: Analysis revealed that with values of slope angle and meniscus-bone angle increasing by one degree, the risk of meniscus extrusion raises by 1.157 and 1.078 respectively. Also, an increase in meniscus-cartilage height by 1 mm significantly elevates the risk of extrusion. At the same time it was demonstrated that for meniscus-bone angle values over 42 degrees and slope angle over 37 degrees the risk of extrusion increases significantly., Conclusions: This was the first study to demonstrate a tight correlation between slope angle, meniscus-bone angle and meniscus-cartilage height values in the assessment of the risk of lateral meniscus extrusion. Insertion of the above parameters to the radiological assessment of the knee joint allows identification of patients characterized by an elevated risk of development of this pathology.
- Published
- 2016
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29. Premature Destruction of Microbubbles during Voiding Urosonography in Children and Possible Underlying Mechanisms: Post Hoc Analysis from the Prospective Study.
- Author
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Piskunowicz M, Swieton D, Rybczynska D, Szarmach A, Szurowska E, and Pruijm M
- Subjects
- Adolescent, Child, Child, Preschool, Crying, Female, Humans, Infant, Infant, Newborn, Male, Prospective Studies, Urinary Bladder diagnostic imaging, Contrast Media adverse effects, Microbubbles adverse effects, Ultrasonography methods
- Abstract
The aim of this study is to describe premature microbubbles destruction with contrast-enhanced voiding urosonography (ce-VUS) in children using 2nd-generation ultrasound contrast agents (UCA) and to hypothesize about the reason. 141 children (61 females and 80 males) were included in the study, with mean age of 3.3 years (range 4 weeks-16.0 years), who underwent ce-VUS examination between 2011 and 2014. Premature destruction of the microbubbles in the urinary bladder during ce-VUS was observed in 11 children (7.8%). In all these cases the voiding phase of ce-VUS examination could not be performed because of destroyed UCA microbubbles. This was noted in anxious, crying infants and children with restricted voiding. The premature destruction of ultrasound contrast agent during ce-VUS is an underreported, important limitation of ce-VUS, which prevents evaluation of the voiding phase and the establishment of vesicoureteric reflux (VUR). This was particularly noted in crying infants and children., Competing Interests: The authors declare that they have no competing interests.
- Published
- 2016
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30. Subtotal Cerebral Circulatory Arrest With Preserved Breathing Activity: A Case Report.
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Wujtewicz MA, Szarmach A, Chwojnicki K, Sawicki M, and Owczuk R
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- Aged, Angiography, Digital Subtraction methods, Brain blood supply, Brain Death physiopathology, Brain Infarction complications, Brain Stem physiopathology, Cerebral Angiography methods, Humans, Male, Preservation, Biological, Respiration, Brain Death diagnosis, Brain Infarction physiopathology, Cerebrovascular Circulation
- Abstract
A suspicion of brain death (BD) is the 1st step in the process of BD certification. Owing to its utmost importance, the process must yield an unequivocal answer so that the committee for the determination of BD has no doubts. We present a case of a patient with suspected BD, with a diagnosis of no intracranial flow in 4-vessel digital-subtraction angiography, who developed some reflexes just before clinical examination for BD assessment. The source of clinical findings was determined to be an extracranial blood supply, which enabled the preservation of trace lower brain stem functioning., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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31. Dynamics of quality of life improvement after floppy Nissen fundoplication for gastroesophageal reflux disease.
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Kobiela J, Kaska Ł, Pindel M, Szarmach A, Janiak M, Proczko-Markuszewska M, Stefaniak T, Łaski D, Łachiński A, and Śledziński Z
- Abstract
Introduction: Gastroesophageal reflux disease (GERD) has a negative impact on global quality of life (QOL) of patients. In patients affected by GERD, laparoscopic Nissen fundoplication is one of the most commonly performed laparoscopic procedures worldwide., Aim: To prospectively analyze the dynamics of QOL as well as severity of pain in patients with GERD, before and after laparoscopic floppy Nissen fundoplication., Material and Methods: The study involved 104 consecutive patients operated on for GERD in whom laparoscopic floppy Nissen fundoplication was performed. QOL was assessed before surgery and 1, 3, 6, 12 and 24 months after. The following instruments were used: FACIT-G, FACIT-TS-G, GIQLI, GERD symptom scale., Results: It was found that symptom relief and quality of life improvement presented different dynamics in the postoperative course. Observations revealed relief of symptoms 1 month after surgery and improvement in QOL related to the gastrointestinal tract and pain 3 months after surgery. Global QOL increased significantly as late as 12 months after surgery., Conclusions: Gastroesophageal reflux disease is a chronic disease of long duration, leading to impairment of quality of life. Patients, apart from typical symptoms of GERD, suffer from pain of significant severity. QOL improves significantly after surgery. Surgical treatment results in relief of GERD symptoms, which leads to gradual improvement of QOL.
- Published
- 2015
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32. Radiation safety awareness among medical staff.
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Szarmach A, Piskunowicz M, Świętoń D, Muc A, Mockałło G, Dzierżanowski J, and Szurowska E
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Background: The common access to imaging methods based on ionizing radiation requires also radiation protection. The knowledge of ionizing radiation exposure risks among the medical staff is essential for planning diagnostic procedures and therapy. Evaluation of the knowledge of radiation safety during diagnostic procedures among the medical staff., Material/methods: The study consisted of a questionnaire survey. The questionnaire consisted of seven closed-ended questions concerning the knowledge of the effects of exposure to ionizing radiation as well as questions related to responder's profession and work experience. The study group included a total of 150 individuals from four professional groups: nurses, doctors, medical technicians, support staff. The study was carried out in the three largest hospitals in Gdańsk between July and October 2013., Results: The highest rates of correct answers to questions related to the issue of radiation protection were provided by the staff of radiology facilities and emergency departments with 1-5 years of professional experience. The most vulnerable group in terms of the knowledge of these issues consisted of individuals working at surgical wards with 11-15 years of professional experience., Conclusions: Education in the field of radiological protection should be a subject of periodic training of medical personnel regardless of position and length of service.
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- 2015
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33. The posterior communicating artery: morphometric study in 3D angio-computed tomography reconstruction. The proof of the mathematical definition of the hypoplasia.
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Dzierżanowski J, Szarmach A, Słoniewski P, Czapiewski P, Piskunowicz M, Bandurski T, and Szmuda T
- Abstract
Background: The aim of this study was to investigate the morphometry of the posterior communicating artery (PCoA), on the basis of angio-computed tomography (CT), and to give proof of the mathematical definition of the term "hypopal sia of the PCoA"., Materials and Methods: One hundred 3-dimensional (3D) angio-CT images, performed in adult patients with bilateral reconstruction of the PCoA (200 results) were used tocalculate the morphometry of the vessel., Results: The average length of the vessel on the right side was 14.48 ± 3.47 mm, andon the left side 14.98 ± 4.77 mm (in women 14.75 mm, in men 14.70 mm). The mean of the diameter at the "proximal" point (the junction with P1) on the right side was 1.49 ± 0.51 mm, and on the left 1.46 ± 0.47 mm (in women 1.44 mm and in men 1.51 mm). The mean of the diameter in the "distal" part (the connection with ICA) on the right side was 1.4 ± 0.49 mm, and on the left 1.37 ± 0.41 mm (in women 1.38 mm, and in men 1.39 mm). No statistical correlation between the length and the diameter of the PCoA in relation to the sex and side was shown. On the basis of our measurements, we defined the hypoplasia of the artery as the estimated value less than the average diameter minus the standard deviation. The percentage distribution was as follows: the left artery 15.5%, the right artery 24%, women 11.5%, and the men 9%. Similarly to the above parameters, we have not found any statistical differences. The presence of the foetal origin was noted in 25% of the radiological examinations. The infundibular widening was visualised in 11.5% of cases of 3D reconstructions. The agenesis of PCoA was found in 9% (never bilaterally), and in 1 case the unilateral duplication of the artery was observed. No statistical differences between those parameters in relation to sex and the examined side were revealed., Conclusions: Morphological calculation of the PCoA on the basis of angio-CT from adult patients did not show any statistical differences depending on sex or the investigated side. The presented method of the calculations proved to be useful for the mathematical definition of the term "hypoplasia of the PCoA".
- Published
- 2014
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34. [Krukenberg tumor--a multidisciplinary approach--a case report].
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Szarmach A, Swietoń D, Szydłowska-Szarmach E, Szurowska E, Kowalski J, Gorycki T, and Piskunowicz M
- Subjects
- Female, Gastrectomy, Humans, Middle Aged, Stomach Neoplasms pathology, Treatment Outcome, Ultrasonography, Krukenberg Tumor diagnostic imaging, Krukenberg Tumor secondary, Ovarian Neoplasms diagnostic imaging, Ovarian Neoplasms secondary, Stomach Neoplasms surgery
- Abstract
Metastatic lesions within the ovary constitute a serious diagnostic problem in daily practice. We present an interesting case of Krukenberg tumor in a woman 13 years after partial gastrectomy due to stomach cancer. Our case confirms that every woman with history of cancer should remain under gynecological control. It is important due to a high risk of metastatic changes localized in the ovaries, regardless of the time elapsed since the diagnosis of the primary tumor
- Published
- 2014
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35. Intravenous ultrasound contrast agents versus other imaging methods in pediatric patients with neoplastic diseases - a comparison.
- Author
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Piskunowicz M, Kosiak W, Batko T, Adamkiewicz-Drożyńska E, and Szarmach A
- Abstract
The lack of registration of ultrasound contrast agents for use in patients below the age of 18 is a significant limitation of their usage. Despite this, examinations with the use of contrast agents are conducted in numerous centers, mainly as part of the diagnostic process of vesicoureteral reflux. Examinations after an intravenous administration of contrast agents are conducted rarely. The reason for this is not only the lack of registration, but also the lack of studies on their safety profile in paediatric patients or no guidelines concerning the dosage. It seems that imaging with the use of such agents could help solve certain clinical problems when other diagnostic methods fail. The paper presents selected cases of pediatric patients treated in oncological departments, in whom the examination with the use of ultrasound contrast agents had a considerable influence on the diagnostic and therapeutic process.
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- 2013
- Full Text
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36. Near-infrared transillumination back scattering sounding--new method to assess brain microcirculation in patients with chronic carotid artery stenosis.
- Author
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Frydrychowski AF, Winklewski PJ, Szarmach A, Halena G, and Bandurski T
- Subjects
- Acetazolamide pharmacology, Acetazolamide therapeutic use, Aged, Aged, 80 and over, Blood Volume drug effects, Carotid Stenosis drug therapy, Chronic Disease, Female, Humans, Infrared Rays, Male, Middle Aged, Pulse, Pulse Wave Analysis, Subarachnoid Space pathology, Systole drug effects, Time Factors, Carotid Stenosis physiopathology, Cerebrovascular Circulation drug effects, Microcirculation drug effects, Transillumination methods
- Abstract
Purpose: The purpose of the study was to assess the responses of pial artery pulsation (cc-TQ) and subarachnoid width (sas-TQ) to acetazolamide challenge in patients with chronic carotid artery stenosis and relate these responses to changes in peak systolic velocity (PSV), cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak response (TTP)., Methods: Fifteen patients with carotid artery stenosis ≥ 90% on the ipsilateral side and <50% on the contralateral side were enrolled into the study. PSV was assessed using colour-coded duplex sonography, CBF, CBV, MTT and TTP with perfusion computed tomography, cc-TQ and sas-TQ with near-infrared transillumination/backscattering sounding (NIR-T/BSS)., Results: Based on the ipsilateral/contralateral cc-TQ ratio after acetazolamide challenge two groups of patients were distinguished: the first group with a ratio ≥ 1 and the second with a ratio <1. In the second group increases in CBF and CBV after the acetazolamide test were significantly higher in both hemispheres (ipsilateral: +33.0% ± 8.1% vs. +15.3% ± 4.4% and +26.3% ± 6.6% vs. +14.3% ± 5.1%; contralateral: +26.8% ± 7.0% vs. +17.6% ± 5.6% and +20.0% ± 7.3% vs. +10.0% ± 3.7%, respectively), cc-TQ was significantly higher only on the ipsilateral side (+37.3% ± 9.3% vs. +26.6% ± 8.6%) and the decrease in sas-TQ was less pronounced on the ipsilateral side (-0.7% ± 1.5% vs. -10.2% ± 1.5%), in comparison with the first group. The changes in sas-TQ following the acetazolamide test were consistent with the changes in TTP., Conclusions: The ipsilateral/contralateral cc-TQ ratio following acetazolamide challenge may be used to distinguish patient groups characterized by different haemodynamic parameters. Further research on a larger group of patients is warranted.
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- 2013
- Full Text
- View/download PDF
37. Subarachnoid space: new tricks by an old dog.
- Author
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Frydrychowski AF, Szarmach A, Czaplewski B, and Winklewski PJ
- Subjects
- Adolescent, Adult, Cerebrovascular Circulation physiology, Female, Humans, Magnetic Resonance Imaging, Male, Sex Factors, Young Adult, Subarachnoid Space anatomy & histology
- Abstract
Purpose: The purpose of the study was to: (1) evaluate the subarachnoid space (SAS) width and pial artery pulsation in both hemispheres, and (2) directly compare magnetic resonance imaging (MRI) to near-infrared transillumination/backscattering sounding (NIR-T/BSS) measurements of SAS width changes in healthy volunteers., Methods: The study was performed on three separate groups of volunteers, consisting in total of 62 subjects (33 women and 29 men) aged from 16 to 39 years. SAS width was assessed by MRI and NIR-T/BSS, and pial artery pulsation by NIR-T/BSS., Results: In NIR-T/BSS, the right frontal SAS was 9.1% wider than the left (p<0.01). The SAS was wider in men (p<0.01), while the pial artery pulsation was higher in women (p<0.01). Correlation and regression analysis of SAS width changes between the back- and abdominal-lying positions measured with MRI and NIRT-B/SS demonstrated high interdependence between both methods (r = 0.81, p<0.001)., Conclusions: NIR-T/BSS and MRI were comparable and gave equivalent modalities for the SAS width change measurements. The SAS width and pial artery pulsation results obtained with NIR-T/BSS are consistent with the MRI data in the literature related to sexual dimorphism and morphological asymmetries between the hemispheres. NIR-T/BSS is a potentially cheap and easy-to-use method for early screening in patients with brain tumours, increased intracranial pressures and other abnormalities. Further studies in patients with intracranial pathologies are warranted.
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- 2012
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38. Evaluation of changes in the parameters of brain tissue perfusion in multi-slice computed tomography in patients after carotid artery stenting.
- Author
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Szarmach A, Halena G, Buczny J, Studniarek M, Markiet K, Szurowska E, Retkowski M, and Piskunowicz M
- Abstract
Background: CT perfusion of the brain allows functional evaluation of cerebral blood flow. Patients with chronic internal carotid artery (ICA) stenosis may suffer from malperfusion. Improvement of cerebral blood flow and remission of neurological symptoms indicate the effectiveness of treatment of internal carotid artery stenosis., Material/methods: The aim of the study was to analyze alterations within cerebral perfusion parameters in CT brain perfusion examination in patients who were scheduled for endovascular therapy due to ICA stenosis. Forty patients with ICA stenosis of over 79% who were included in this prospective study underwent perfusion CT examination twice - 24 hours prior to stenting and after 6-8 weeks following the procedure. CBF, CBV, MTT and TTP were evaluated., Results: Prior to endovascular therapy, an increase in MTT and TTP, and a decrease in CBV and CBF were observed within arterial supply of the hemisphere ipsilateral to stenosis. After the procedure, a decrease in MTT and TTP was seen in all cases, while no statistically significant changes of CBF or CBV were observed. MTT proved to be the most sensitive indicator of ICA stenosis, as its values allowed differentiation between critical and non-critical stenosis. No correlation between the degree of ICA stenosis and TTP values was found. Mild cerebral hyperperfusion syndrome (CHS) was observed in only one patient and the difference between pre-treatment MTT values calculated for both hemispheres was shown to be a prognostic factor for CHS incidence., Conclusions: Endovascular stent placing in patients with hemodynamically significant internal carotid artery stenosis results in alteration of perfusion parameters, especially concerning TTP and MTT.
- Published
- 2011
39. Is hepatotropic contrast enhanced MR a more effective method in differential diagnosis of hemangioma than multi-phase CT and unenhanced MR?
- Author
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Szurowska E, Nowicki T, Izycka-Swieszewska E, Wypych J, Drobinska-Jurowiecka A, Markiet K, Szarmach A, and Studniarek M
- Subjects
- Adolescent, Adult, Aged, Diagnosis, Differential, Female, Humans, Male, Middle Aged, Prospective Studies, Sensitivity and Specificity, Young Adult, Contrast Media, Hemangioma, Cavernous diagnostic imaging, Liver Neoplasms diagnostic imaging, Magnetic Resonance Imaging methods, Meglumine analogs & derivatives, Organometallic Compounds, Tomography, X-Ray Computed methods
- Abstract
Background: Cavernous hemangiomas are the most frequent neoplasms of the liver and in routine clinical practice they often need to be differentiated from malignant tumors and other benign focal lesions. The purpose of this study is to evaluate whether diagnostic accuracy of magnetic resonance imaging (MRI) of hepatic hemangiomas, showing atypical pattern on US, improves with the use of Gd-BOPTA in comparison with contrast-enhanced multi-phase computed tomography (CT)., Methods: 178 consecutive patients with ambiguous hepatic masses showing atypical hyperechoic pattern on grey-scale US, underwent unenhanced and contrast-enhanced multi-phase multi-detector CT and MR (1.5T) with the use of liver-specific contrast medium gadobenate dimeglumine (Gd-BOPTA). After intravenous contrast administration arterial (HAP), venous-portal (PVP), equilibrium phases (EP) both in CT and MR and additionally hepatobiliary phase (HBP) in MR were obtained. 398 lesions have been detected including 99 hemangiomas and 299 other lesions., Results: In non-enhanced MDCT examination detection of hemangiomas was characterized by sensitivity of 76%, specificity of 90%, PPV of 71%, NPV of 92% and accuracy of 86%.Non-enhanced MR examination showed sensitivity of 98%, specificity of 99%, PPV of 99%, NPV of 99% and accuracy of 99%.After intravenous administration of contrast medium in MR the mentioned above parameters did not increase significantly., Conclusion: Gd-BOPTA-enhanced MR in comparison with unenhanced MRI does not improve diagnostic accuracy in discriminating hemangiomas that show non-specific appearance in ultrasound examination. Unenhanced MR as a method of choice should directly follow US in course of diagnostic algorithm in differentiation of hemangiomas from other liver tumors.
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- 2011
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40. [Acute ethanol and drug poisoning in alcohol abusers].
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Chodorowski Z, Sein Anand J, Ciechanowicz R, Szarmach A, and Wnuk K
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- Acute Disease, Adolescent, Adult, Aged, Alcoholism complications, Catchment Area, Health, Female, Humans, Male, Middle Aged, Poisoning complications, Poisoning epidemiology, Poisoning rehabilitation, Poland epidemiology, Alcoholism epidemiology, Ethanol adverse effects, Narcotics adverse effects
- Abstract
In the period from 1997 to 1999 one hundred twenty one alcohol abusers were admitted to the clinic with acute ethanol and drug poisoning, including 95 men and 26 women from 18 to 69 (mean 36) years old. Fifty eight persons were poisoned by ethanol, in remaining 63 cases intoxications were mixed e.g. including benzodiazepines, tricyclic antidepressants, carbamazepine, amphetamine, phenothiazines, barbiturates, theophylline, salicylates. In the mixed poisonings group two men (3.2%) died at the age above 50 years old suffering from congestive heart failure, bronchopneumonia and ventricular fibrillation. In the ethanol intoxication group there was no fatal case.
- Published
- 2000
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