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OBJECTIVE: EPI DWI is a routinely used sequence in brain imaging but it has limitations when it comes to SNR and artifact reduction. PROPELLER DWI has the benefit of improving image quality compared to EPI DWI. The aim of this study is to compare the EPI DWI sequence in brain MR imaging with the PROPELLER DWI sequence. The objective is to identify which sequence is more beneficial in brain imaging by evaluating image quality and the depiction of pathologies. MATERIALS AND METHODS: A total of 101 patients (55 females and 46 males, mean age 56 years) underwent brain MRI examination on a 1.5 T scanner. EPI DWI and PROPELLER DWI sequences were acquired in every exam and were reviewed by 2 radiologists. The images were evaluated by performing a quantitative analysis based on Relative Contrast and a qualitative analysis (overall image quality, conspicuousness of lesions, artifact reduction, etc.). RESULTS: In both the qualitative and quantitative analysis PROPELLER DWI achieved better results than EPI DWI. PROPELLER DWI showed statistical significance in the overall image quality (P < 0.001), the elimination of susceptibility (P < 0.001) and flow pulsation artifacts (P < 0.001), as well as in the contrast between CSF with white (P < 0.001) and grey matter (P < 0.001). Also, PROPELLER DWI presented better delineation of pathologies like ischemic strokes, metastasis, tumors and vasogenic edemas than conventional EPI DWI. CONCLUSION: PROPELLER DWI was the preferred sequence during the image evaluation. Compared to EPI DWI, PROPELLER DWI managed to reduce susceptibility and flow pulsation whilst achieving higher image quality and lesion delineation and earlier depiction of ischemic strokes than the conventional EPI DWI. PROPELLER DWI may be incorporated in brain MR imaging replacing EPI DWI.
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Imagem de Difusão por Ressonância Magnética , AVC Isquêmico , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Imagem de Difusão por Ressonância Magnética/métodos , Sensibilidade e Especificidade , Imagem Ecoplanar/métodos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Artefatos , Reprodutibilidade dos TestesRESUMO
PURPOSE: To visualize the meniscus of the knee joint in the axial plane and identify injuries that cannot be visualized using conventional sequences. METHODS: Two hundred and two subjects underwent an improvised 3-Dimensional Proton Density Fat Saturation (3D-PD FS) Magnetic Resonance (MR) sequence on their meniscus. The transverse images were reconstructed and examined. Fifty-three of the subjects had a healthy meniscus and their images were used as part of a qualitative evaluation to verify that all parts of the meniscus were properly visualized. The evaluation was based on a four-level scale indicating the visualization of meniscal parts. The same evaluation was also performed on the 149 subjects with meniscal pathologies. Another qualitative evaluation was performed on all subjects concerning five image characteristics based on a five-level scale. Finally, images from 20 patients with meniscal pathologies were compared with arthroscopic images visualizing meniscal tears. RESULTS: In all subjects, all parts of the meniscus were clearly visualized. The axial reformats provided ideal imaging of the meniscus, yielding high total image quality, satisfactory smoothing and sharpening, fewer artifacts, and successful fat saturation. The findings of the MR images from the 20 subjects with meniscal pathologies, concerning the topography of meniscal tears coincided at 100% with their arthroscopic findings. CONCLUSION: The use of the improvised 3D-PD FS sequence provides the possibility of axial reconstruction with a better depiction of the meniscus. These images can accurately illustrate the range of the meniscus and any meniscal tears along with their exact location with high image quality.
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Imageamento por Ressonância Magnética , Menisco , Artefatos , Humanos , Menisco/diagnóstico por imagemRESUMO
BACKGROUND: The coronavirus outbreak (COVID-19) tested health care systems worldwide. This qualitative study aimed to explore and understand the experiences, beliefs and concerns of Primary Care Professionals (PCPs) regarding the preparedness and response of primary care to the first wave of the pandemic in Greece, a country where a public structured primary care system has been developing. METHODS: We conducted semi-structured telephone interviews with 33 PCPs (General Practitioners, community General Internal Medicine Specialists, community Paediatricians and nurses) recruited from all regions of Greece after the first wave of the pandemic (June 2020). Interviews were transcribed verbatim, data were anonymised and analysed. Thematic analysis was applied developing a conceptual framework. RESULTS: Four main themes were identified: a) Primary care unit adaptation and issues faced during the pandemic; b) Management of suspected COVID-19 cases; c) Management of non-suspected cases; d) Consequences of the pandemic. In the first phase of the pandemic, remote management of suspected cases and their referral to the hospital were preferred as a result of a shortage of personal protective equipment and inaccessibility to coronavirus testing in primary care. Due to the discontinuation of regular medical services and the limited in-person contact between doctors and patients, chronic disease management and prevention programmes were left behind. Social and emotional consequences of the pandemic, such as workplace stigma, isolation and social seclusion, deriving from fear of viral transmission, as well as burnout symptoms and exhaustion were commonly experienced among PCPs. Positive consequences of the pandemic were considered to be the recognition of the importance of an empowered public healthcare system by citizens and the valuable insight, knowledge and experience professionals gained in times of crisis. CONCLUSIONS: Primary care has a key role to play during and after the pandemic by using its information infrastructure to identify at-risk groups, detect new cases of COVID-19, provide care according to needs, and carry out vaccination programmes. Central coordination and empowerment of primary care will increase its effectiveness, via public awareness, holistic patient management, and unburdening of hospitals.
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COVID-19 , Pandemias , Teste para COVID-19 , Grécia/epidemiologia , Humanos , Atenção Primária à Saúde , SARS-CoV-2RESUMO
OBJECTIVE: This study aims at identifying, classifying, and measuring the frequency the different artifacts that show up in the images of the Sagittal T1 Fluid Attenuated Inversion Recovery (FLAIR) sequence. MATERIALS AND METHODS: A total of 101 subjects underwent brain magnetic resonance imaging examination with the following sequences: Axial T1 FLAIR, Axial T2-weighted imaging, Diffusion Weighted Imaging, 2D Multiple Echo Recombined Gradient Echo, Sagittal T1 FLAIR, Coronal T2 Turbo Spin Echo, Spin Echo T1-weighted imaging, and 3D Fast Spoiled Gradient-echo. In these images, we observed the following categories of artifacts: (a) ghost artifacts, (b) aliasing behind the occipital bone, (c) aliasing inside the sphenoid cavity, (d) susceptibility artifacts, and (e) pulsation artifacts. In order to recognize and verify the artifacts, we used not only the Sagittal T1 FLAIR sequence, but also Sagittal reconstructions from the 3-dimensional Fast Spoiled Gradient-echo sequence and the other routine sequences. RESULTS: Aliasing artifacts and especially aliasing of nose are present in 41% of the cases. In 45% of these cases the uncommon aliasing artifacts, which took place into the brain parenchyma (sphenoid cavity, subarachnoid bay, or pituitary) originated from nose. In 33% of the subjects, ghost artifacts are presented, which stem from the nose, the orbits, or other pulsating structures (pulsation artifacts) or even from fat tissue. Moreover, susceptibility artifacts comprise 8% of all the artifacts. Finally, 19% of brains were presented without artifact. CONCLUSIONS: We suggest in addition to T1 FLAIR, the application of Sagittal SE or TSE sequences in magnetic resonance imaging examination of brain, trying to include the nose in the square of FOV.
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Artefatos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Humanos , NeuroimagemRESUMO
PURPOSE: Although frailty can be delayed or prevented by appropriate interventions, these are often not available in countries lacking formal education and infrastructure in geriatrics. The aim of this study was to: (a) explore ideas, perceptions and attitudes of primary health care (PHC) professionals towards frailty in a country where geriatrics is not recognised as a specialty; (b) explore PHC professionals' training needs in frailty; and (c) define components of a frailty educational programme in PHC. METHODS: Qualitative design, using two focus groups with PHC professionals conducted in Thessaloniki, Greece. Focus groups were audio recorded and transcribed. Data were analysed with thematic analysis. RESULTS: In total 31 PHC professionals (mean age: 46 years; gender distribution: 27 females, 4 males) participated in the study (physicians n = 17; nurses n = 12; health visitors n = 2). Four main themes were identified: (1) Perceptions and understanding of frailty; (2) Facilitators and barriers to frailty identification and management; (3) Motivation to participate in a frailty training programme; (4) Education and training. The main barriers for the identification and management of frailty were associated with the healthcare system, including duration of appointments, a focus on prescribing, and problems with staffing of allied health professionals, but also a lack of education. Training opportunities were scarce and entirely based on personal incentive. Professionals were receptive to training either face-to-face or online. A focus on learning practical skills was key. CONCLUSION: Education and training of professionals and interdisciplinary collaboration are essential and much needed for the delivery of person-centred care for people with frailty living in the community.
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Fragilidade , Atitude , Feminino , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Atenção Primária à SaúdeRESUMO
PURPOSE: To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space covering') to significantly reduce motion, truncation, flow and other artifacts in cervical spine compared to the conventional technique. MATERIALS AND METHODS: In eighty consecutive subjects, who had been routinely scanned for cervical spine examination, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0: non-visualization; 1: poor; 2: average; 3: good; 4: excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). RESULTS: In quantitative analysis, the CNR values of the CSF/SC between TIRM SAG and TIRM SAG BLADE were found to present statistically significant differences (p < 0.001). Regarding motion and truncation artifacts, the T2 TSE BLADE SAG was superior compared to the T2 TSE SAG, and the T2 TIRM BLADE SAG was superior compared to the T2 TIRM SAG. Regarding flow artifacts, T2 TIRM BLADE SAG eliminated more artifacts than T2 TIRM SAG. CONCLUSIONS: In cervical spine MRI, BLADE sequences appear to significantly reduce motion, truncation and flow artifacts and improve image quality. BLADE sequences are proposed to be used for uncooperative subjects. Nevertheless, more research needs to be done by testing additional specific pathologies.
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Vértebras Cervicais/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , Adolescente , Adulto , Algoritmos , Artefatos , Meios de Contraste/química , Diagnóstico por Imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Adulto JovemRESUMO
The purpose of this study is to report the significant differences found in the identification of lesions in cervical spinal cord of two patients with multiple sclerosis when using the BLADE T2-TSE and BLADE T2-TIRM sequences as opposed to the conventional T2-TSE and T2-TIRM sequences for sagittal acquisition at 1.5T. In both patients, one more lesion was identified with the BLADE sequences than with the conventional ones. Consequently, we suggest the use of BLADE T2-TSE and BLADE T2-TIRM sequences in place of conventional ones for sagittal examination of the cervical spinal cord of multiple sclerosis patients. The advantages of ΤΙRΜ to reveal the pathology of the cervical spinal cord and the advantage of BLADE sequences to improve image quality should be combined in a sequence that could be ideal for cervical spinal cord examinations.
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Algoritmos , Vértebras Cervicais/patologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/patologia , Medula Espinal/patologia , Feminino , Humanos , Posicionamento do Paciente/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
The purpose of this study, is to compare the sequences: 1) proton density (PD) BLADE (BLADE is a PROPELLER-equivalent implementation of the Siemens Medical System) with fat saturation (FS) coronal (COR), 2) PD FS COR, 3) multi-planar reconstruction (MPR) with 3mm slice thickness and 4) multi-planar reconstruction (MPR) with 1.5mm slice thickness, both from the T2 3D-double-echo steady state (DESS) with water excitation (WE) sagittal (SAG), regarding their abilities to identify changes in the femorotibial condyle cartilage in knee MRI examinations. Thirty three consecutive patients with osteoarthritis (18 females, 15 males; mean age 56years, range 37-71years), who had been routinely scanned for knee examination using the previously mentioned image acquisition techniques, participated in the study. A quantitative analysis was performed based on the relative contrast (ReCON) measurements, which were taken both on normal tissues as well as on pathologies. Additionally, a qualitative analysis was performed by two radiologists. Motion and pulsatile flow artifacts were evaluated. The PD BLADE FS COR sequence produced images of higher contrast between Menisci and Cartilage, Fluid and Cartilage, Pathologies and Cartilage as well as of the Conspicuousness Superficial Cartilage and it was found to be superior to the other sequences (p<0.001). The sequences T2 3D DESS 1.5mm and T2 3D DESS 3mm were significantly superior to the PD BLADE FS COR and the PD FS COR sequences in the visualization of Bone and Cartilage and the Conspicuousness Deep Surface Cartilage. This pattern of results is also confirmed by the quantitative analysis. PD FS BLADE sequences are ideal for the depiction of the cartilage pathologies compared to the conventional PD FS and T2 3D DESS sequences.
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Tecido Adiposo/patologia , Algoritmos , Cartilagem Articular/patologia , Interpretação de Imagem Assistida por Computador/métodos , Articulação do Joelho/patologia , Osteoartrite do Joelho/patologia , Tecido Adiposo/metabolismo , Adulto , Idoso , Água Corporal/metabolismo , Cartilagem Articular/metabolismo , Feminino , Humanos , Aumento da Imagem/métodos , Articulação do Joelho/metabolismo , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
The purpose of this study is to evaluate the ability of T2 turbo spin echo (TSE) axial and sagittal BLADE sequences in reducing or even eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MRI examinations. Forty four patients, who had routinely undergone a lumbar spine examination, participated in the study. The following pairs of sequences with and without BLADE were compared: a) T2 TSE Sagittal (SAG) in thirty two cases, and b) T2 TSE Axial (AX) also in thirty two cases. Both quantitative and qualitative analyses were performed based on measurements in different normal anatomical structures and examination of seven characteristics, respectively. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion, pulsatile flow and cross-talk artifacts was evaluated. Based on the results of the qualitative analysis for the different sequences and anatomical structures, the BLADE sequences were found to be significantly superior to the conventional ones in all the cases. The BLADE sequences eliminated the motion artifacts in all the cases. In our results, it was found that in the examined sequences (sagittal and axial) the differences between the BLADE and conventional sequences regarding the elimination of motion, pulsatile flow and cross-talk artifacts were statistically significant. In all the comparisons, the T2 TSE BLADE sequences were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. In conclusion, this technique appears to be capable of potentially eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MR images and producing high quality images in collaborative and non-collaborative patients.
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Algoritmos , Artefatos , Interpretação de Imagem Assistida por Computador/métodos , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Doenças da Coluna Vertebral/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Movimento , Fluxo Pulsátil , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Razão Sinal-Ruído , Adulto JovemRESUMO
BACKGROUND: Bacterial meningitis continues to be a serious, often disabling infectious disease. The aim of this study was to assess the possibility that treatment influences the development of sequelae in childhood bacterial meningitis. METHODS: Two thousand four hundred and seventy-seven patients aged 1 month to 14 years with acute bacterial meningitis over a 32-year period were enrolled in the study. Data were collected prospectively from the Meningitis Registry of a tertiary university teaching hospital in Athens, Greece. Treatment was evaluated through univariate and multivariate analysis with regard to sequelae: seizure disorder, severe hearing loss, ventriculitis, and hydrocephalus. RESULTS: According to the multinomial logistic regression analysis, there was evidence that penicillin, an all-time classic antibiotic, had a protective effect on the occurrence of ventriculitis (odds ratio (OR) 0.17, 95% confidence interval (CI) 0.05-0.60), while patients treated with chloramphenicol had an elevated risk of ventriculitis (OR 17.77 95% CI 4.36-72.41) and seizure disorder (OR 4.72, 95% CI 1.12-19.96). Cephalosporins were related to an increased risk of hydrocephalus (OR 5.24, 95% CI 1.05-26.29) and ventriculitis (OR 5.72, 95% CI 1.27-25.76). The use of trimethoprim/sulfamethoxazole increased the probability of seizure disorder (OR 3.26, 95% CI 1.08-9.84) and ventriculitis (OR 8.60, 95% CI 2.97-24.91). Hydrocortisone was associated with a rise in hydrocephalus (OR 5.44, 95% CI 1.23-23.45), while a protective effect of dexamethasone (OR 0.82, 95% CI 0.18-3.79) was not statistically significant. CONCLUSIONS: Current study findings suggest that the type of antimicrobial treatment for childhood bacterial meningitis may influence in either a positive or a negative way the development of neurological sequelae.
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Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Meningites Bacterianas/complicações , Meningites Bacterianas/tratamento farmacológico , Doenças do Sistema Nervoso/epidemiologia , Doenças do Sistema Nervoso/etiologia , Adolescente , Criança , Pré-Escolar , Comorbidade , Grécia , Humanos , Lactente , Recém-Nascido , Meningites Bacterianas/microbiologia , Mortalidade , Sistema de RegistrosRESUMO
PURPOSE: The purpose of the present study was to evaluate the visibility and the image quality of the biliary and pancreatic duct system on magnetic resonance cholangiopancreatography (MRCP) images based on two breath-hold (BH) methods using array spatial sensitivity technique: a single-shot fast spin-echo (SS-FSE) sequence and a three-dimensional single slab fast spin-echo (3D-FSE) sequence. MATERIALS AND METHODS: In the present prospective comparative study, 47 patients (22 male and 25 female, mean age=50 years, age range=22-82 years) that were referred for MRCP during a 12-month period are included. All of them were referred with suspected pancreaticobiliary disease. All patients underwent MRCP with both a SS-FSE BH sequence and a 3D-FSE BH sequence. Qualitative evaluation regarding the depiction of three segments of the pancreaticobiliary tree and the frequency of artifacts was performed. Two radiologists graded each sequence of the obtained studies in a blinded fashion. Quantitative evaluation including calculation of relative signal intensity (rSI) and relative contrast (RC) ratios at seven segments of the pancreaticobiliary tree between fluid-filled ductal structures and organ parenchyma at the same ductal segments was performed. In order to evaluate the parameters' differences of the two sequences, either in qualitative or in quantitative analysis, the Wilcoxon paired signed-rank test was performed. RESULTS: On quantitative evaluation, both rSI and RC ratios of all segments of the pancreaticobiliary tree at SS-FSE BH sequence were higher than those at 3D-FSE BH sequences. This finding was statistically significant (P<.01). On qualitative evaluation, the two radiologists found intrahepatic ducts and pancreatic ducts to be better visualized with SS-FSE BH than with 3D-FSE BH sequence. This finding was statistically significant (P<.02). One of them found extrahepatic ducts to be significantly better visualized with SS-FSE BH sequence. Moreover, the frequency of artifacts was lower in the SS-FSE sequence, a finding that was of statistical significance. Interobserver agreement analysis found at least substantial agreement (κ>0.60) between the two radiologists. CONCLUSION: The SS-FSE sequence is performed faster and significantly improves image quality; thus, it should be included into the routine MRCP sequence protocol at 3.0 T. Furthermore, we recommended SS-FSE BH MRCP examination to be applied to uncooperative patients or patients in emergency because of its short acquisition time (1 s).
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Ductos Biliares/patologia , Colangiopancreatografia por Ressonância Magnética/métodos , Ductos Pancreáticos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto JovemRESUMO
The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) examinations of uncooperative and cooperative patients. For each group of patients, the pairs of sequences that were compared were two T2-weighted (T2-W) fluid attenuated inversion recovery sequences with different k-space trajectories (conventional Cartesian and BLADE) and two T2-TSE weighted with different k-space trajectories (conventional Cartesian and BLADE). Twenty-three consecutive uncooperative patients and 44 cooperative patients, who routinely underwent brain MR imaging examination, participated in the study. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio, contrast-to-noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of motion, other (e.g., Gibbs, susceptibility artifacts, phase encoding from vessels) artifacts and pulsatile flow artifacts was evaluated. In the uncooperative group of patients, BLADE sequences were superior to the corresponding conventional sequences in all the cases. Furthermore, the differences were found to be statistically significant in almost all the cases. In the cooperative group of patients, BLADE sequences were superior to the conventional sequences with the differences of the CNR and ReCon values in nine cases being statistically significant. Furthermore, BLADE sequences eliminated motion and other artifacts and T2 FLAIR BLADE sequences eliminated pulsatile flow artifacts. BLADE sequences (T2-TSE and T2 FLAIR) should be used in brain MR examinations of uncooperative patients. In cooperative patients, T2-TSE BLADE sequences may be used as part of the routine protocol and orbital examinations. T2 FLAIR BLADE sequences may be used optionally in examinations of AVM, orbits, haemorrhages, ventricular lesions, lesions in the frontal lobe, periventricular lesions, lesions in regions close to artifacts and lesions in posterior fossa.
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Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Artefatos , Meios de Contraste/farmacologia , Feminino , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Fluxo Pulsátil , Razão Sinal-Ruído , Adulto JovemRESUMO
PURPOSE: The aim of the present study is to investigate means for the reduction or even elimination of enhancement kinetic curve errors due to breast motion in order to avoid pitfalls and to increase the sensitivity and specificity of the method. METHODS: 115 women underwent breast Magnetic Resonance Imaging (MRI). All patients were properly immobilized in a dedicated bilateral phased array coil. A magnetic resonance unit 3-Tesla (Signa, GE Healthcare) was used. The following sequences were applied: (I) axial Τ2-TSE, (II) axial STIR and (III) Vibrant axial T1-weighted fat saturation (six phases). Kinetic curves were derived semi-automatically using the software of the system and manually by positioning the regions of interest (ROI) from stable reference points in all the phases. RESULTS: 376 abnormalities in 115 patients were investigated. In 81 (21.5%) cases, a change of the enhancement kinetic curve type was found when the two different methods were used. In cases of large fatty breasts, a change of the enhancement kinetic curve type in 13 lesions was found. In cases of small and dense breasts, only in 4 lesions the kinetic curve type changed, whereas in cases of small and fatty breasts, the kinetic curve type changed in 64 lesions (50 were observed in left breasts and 14 in right breasts). CONCLUSIONS: The derivation of enhancement kinetic curves should be performed by controlling and verifying that the ROIs lay at the same location of the lesion in all the phases of the dynamic study.
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The purpose of this study is to evaluate the ability of proton density (PD)-BLADE sequences in reducing or even eliminating motion and pulsatile flow artifacts in knee magnetic resonance imaging examinations. Eighty consecutive patients, who had been routinely scanned for knee examination, participated in the study. The following pairs of sequences with and without BLADE were compared: (a) PD turbo spin echo (TSE) sagittal (SAG) fat saturation (FS) in 35 patients, (b) PD TSE coronal (COR) FS in 19 patients, (c) T2 TSE axial in 13 patients and (d) PD TSE SAG in 13 patients. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion and pulsation artifacts was evaluated. Based on the results of the SNR, CRN and ReCon for the different sequences and anatomical structures, the BLADE sequences were significantly superior in 19 cases, whereas the corresponding conventional sequences were significantly superior in only 6 cases. BLADE sequences eliminated motion artifacts in all the cases. However, motion artifacts were shown in (a) six PD TSE SAG FS, (b) three PD TSE COR FS, (c) three PD TSE SAG and (d) two T2 TSE axial conventional sequences. In our results, it was found that, in PD FS sequences (sagittal and coronal), the differences between the BLADE and conventional sequences regarding the elimination of motion and pulsatile flow artifacts were statistically significant. In all the comparisons, the PD FS BLADE sequences (coronal and sagittal) were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. In conclusion, this technique appears to be capable to potentially eliminate motion and pulsatile flow artifacts in MR images.
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Algoritmos , Artefatos , Aumento da Imagem/métodos , Artropatias/patologia , Traumatismos do Joelho/patologia , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Movimento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Adulto JovemRESUMO
Optimal hemodialysis (HD) dose is very important to patients' health and survival, and various indices of adequacy have been incorporated into the current clinical practice to monitor HD efficiency. Exercise during HD could facilitate solute removal; however, it is still unknown whether prolonged intradialytic exercise could further improve HD efficiency. Ten stable "high-functioning" HD patients volunteered to participate. The patients were studied under two scenarios during HD: 1) supine exercise (cycling) for 3 hours at 40% of maximum exercise capacity and 2) no exercise as usual. Blood sampling was acquired pre- and post-HD in both scenarios to calculate the HD efficiency indices. All patients completed the exercise regime with no adverse effects. Rather, all efficiency indices significantly improved in the prolonged exercise scenario, compared with the no-exercise one. In particular Kt/V, urea reduction ratio, and creatinine reduction ratio significantly improved by 20%, 11%, and 26%, respectively, while potassium plasma levels were reduced by 77.5% (p < 0.05). In conclusion, prolonged low-intensity intradialytic exercise improved HD efficiency, with no adverse effects. HD patients should be encouraged to participate in exercise regimes not only for the known long-term benefits regarding their cardiovascular health but also for the acute effect of exercise in the HD adequacy.
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Terapia por Exercício/métodos , Diálise Renal/métodos , Uremia/terapia , Adulto , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Exercício Físico/fisiologia , Terapia por Exercício/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Uremia/sangue , Uremia/fisiopatologiaRESUMO
The purpose of this study was to assess the effect of chemical shift artifacts and fat suppression between contrast-enhanced T1-weighted fast spin-echo (FSE) sequence with fat suppression and contrast-enhanced T1-weighted fluid attenuated inversion recovery (FLAIR) sequence with fat suppression in magnetic resonance imaging (MRI) of the thoracic spine at 3.0T. Forty patients, who underwent MRI examination, were recruited and analyzed both qualitatively and quantitatively. Due to chemical shift artifacts in the T1-weighted FSE, 14 of the patients were found to be of non-diagnostic value. On the contrary, in 11 of those 14 patients, no chemical shift artifacts were observed in the T1-weighted FLAIR sequence. Regarding the efficiency of fat suppression, both sequences achieved successful fat suppression. Consequently, the use of T1-weighted FLAIR fat suppression after contrast administration sequence seems to eliminate or significantly reduce image quality deterioration stemming from chemical shift artifacts in thoracic spine examinations.
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Tecido Adiposo/patologia , Artefatos , Gadolínio DTPA , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Doenças da Coluna Vertebral/patologia , Vértebras Torácicas/patologia , Tecido Adiposo/química , Meios de Contraste , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vértebras Torácicas/químicaRESUMO
OBJECTIVES: Recent studies from several countries have shown that coeliac disease (CD) is increasingly being diagnosed in adults, as the availability of new, accurate serologic tests has made screening in the general population possible. No data exist regarding the prevalence of CD in Greece. The aim of this study was the implementation of a serologic screening procedure for CD in the adult general population of Thessaly, an area of central Greece, using a novel diagnostic algorithm. METHODS: The study included 2230 participants (1226 women, 1004 men, median age 46 years, range 18-80 years), selected by systematic random sampling, from the adult general population of Thessaly. All the serum samples were tested for total immunoglobulin A (IgA)-serum levels, to exclude IgA deficiency. Samples with total IgA within the normal range were tested for IgA antibodies against native human-tissue transglutaminase (anti-tTG); samples that were anti-tTG positive were tested for IgA antiendomysial antibodies (EmA). Samples from participants with selective IgA deficiency were examined for IgG antigliadin antibodies. Participants who were EmA-positive or antigliadin antibody-positive were referred for intestinal biopsy and human leucocyte antigen (HLA) typing. RESULTS: No participant with selective IgA deficiency was detected. Four individuals tested positive for EmA, all of whom were biopsy-proven coeliacs. Therefore, the CD prevalence in this general population sample is 1 : 558 or 1.8 per 1000 (SE 0.13). The four new patients with abnormal histology (two men, two women) were aged between 18 and 35 years. Two of them were considered to be asymptomatic and two presented with a subclinical course. All four had the heterodimer HLA-DQ2. CONCLUSIONS: This first serological screening study for CD in Greece has demonstrated that CD prevalence in Thessaly is among the lowest reported in Europe.
Assuntos
Doença Celíaca/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Doença Celíaca/imunologia , Feminino , Proteínas de Ligação ao GTP/imunologia , Gliadina/imunologia , Grécia/epidemiologia , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Proteína 2 Glutamina gama-Glutamiltransferase , Testes Sorológicos , Transglutaminases/imunologiaRESUMO
The prevalence of celiac disease (CD) and the prevalence and clinical significance of anti-tissue transglutaminase (tTG) antibodies (tTGAbs) in a large series of patients with chronic liver diseases were assessed. We studied 738 patients (462 with chronic viral hepatitis, 117 with autoimmune liver diseases, 113 with alcoholic or nonalcoholic fatty liver disease, and 46 with other liver disorders) and 1,350 healthy controls (HC). Immunoglobulin A (IgA) tTGAbs were measured by enzyme-linked immunosorbent assay and a microsphere-based flow cytometric assay. Positive sera were investigated for IgA antiendomysial antibodies (EmA). IgA tTGAb-positive subjects were invited to undergo a small-intestinal biopsy and HLA-DQ allele typing. Four of 1,350 HC (0.3%) tested tTGAb(+) EmA(+) and underwent a biopsy (CD confirmation in all). Four of 738 liver disease patients tested tTGAbs(+) EmA(+) (0.54%; not statistically significant). Two were HCV infected (1.24%; not statistically significant), and two had transaminasemia of unknown origin. Forty-three patients tested tTGAbs(+) EmA(-) (5.8%; P<0.001 compared to HC). Inhibition experiments verified the existence of specific IgA anti-tTG reactivity. Twenty-six of 43 patients underwent a biopsy (all negative for CD). Binary logistic regression analysis revealed age (P=0.008), cirrhosis (P=0.004), alkaline phosphatase (P=0.026), and antinuclear antibodies (P=0.012) as independent risk factors for tTGAb reactivity among the patients. It was concluded that CD prevalence is the same in HC and patients with chronic liver diseases. The prevalence of tTGAbs is higher in hepatic patients compared to HC, but their specificity for CD diagnosis in this group of patients is low. tTGAbs in patients appear to be associated with the presence of autoimmunity, cirrhosis, and cholestasis, irrespective of the origin of the liver disease.