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Osteoporotic vertebral fractures signify an increased risk of future fractures and mortality and can manifest the diagnosis of osteoporosis. We investigated the prevalence of vertebral fractures in routine CT of patients with long-term hospital records. Three out of ten patients showed osteoporotic vertebral fractures (VFs) corresponding to the highest rates reported in European population-based studies. INTRODUCTION: VFs are a common manifestation of osteoporosis, which influences future fracture risk. Their epidemiology has been investigated in population-based studies. However, few studies report the prevalence of osteoporotic VF in patients seen in clinical routine and include all common fracture levels of the thoracolumbar spine. The purpose of this study was to investigate the prevalence of osteoporotic VF in patients with CT scans and long-term hospital records and identify clinical factors associated with prevalent VFs. METHODS: All patients aged 45 years and older with a CT scan and prior hospital record of at least 5 years that were seen in the study period between September 2008 and May 2017 were reviewed. Imaging requirements were a CT scan with sagittal reformations including at least T6-L4. Patients with multiple myeloma were excluded. Fracture reading was performed using the Genant semi-quantitative method. Medical notes were reviewed for established diagnoses of osteoporosis and clinical information. Clinical factors (e.g. drug intake, chemotherapy, and mobility level) associated with prevalent VF were identified in logistic regression. RESULTS: The study population consisted of 718 patients (228 women and 490 men; mean age 69.3 ± 10.1 years) with mainly cancer staging and angiography CT imaging. The overall prevalence of VFs was 30.5%, with non-significantly more men showing a fracture (32.5%) compared to women (26.3%; p > 0.05). Intake of metamizole for ≥ 3 months was significantly associated with a prevalent VF. Medical records did not include information about bone health in 90% of all patients. CT reports did mention a VF in only 24.7% of patients with a prevalent VF on CT review. CONCLUSION: Approximately 30% of elderly patients with CT imaging and long-term hospital records showed VFs. Only one-quarter of these patients had VFs mentioned in CT reports. Osteoporosis management could be improved by consequent reporting of VFs in CT, opportunistic bone density measurements, and early involvement of fracture liaison services.
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Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Anciano , Densidad Ósea , Femenino , Registros de Hospitales , Humanos , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología , Columna Vertebral , Tomografía Computarizada por Rayos XRESUMEN
The bone marrow proton density fat fraction (PDFF) assessed with MRI enables the differentiation between osteoporotic/osteopenic patients with and without vertebral fractures. Therefore, PDFF may be a potentially useful biomarker for bone fragility assessment. INTRODUCTION: To evaluate whether magnetic resonance imaging (MRI)-based proton density fat fraction (PDFF) of vertebral bone marrow can differentiate between osteoporotic/osteopenic patients with and without vertebral fractures. METHODS: Of the 52 study patients, 32 presented with vertebral fractures of the lumbar spine (66.4 ± 14.4 years, 62.5% women; acute low-energy osteoporotic/osteopenic vertebral fractures, N = 25; acute high-energy traumatic vertebral fractures, N = 7). These patients were frequency matched for age and sex to patients without vertebral fractures (N = 20, 69.3 ± 10.1 years, 70.0% women). Trabecular bone mineral density (BMD) values were derived from quantitative computed tomography. Chemical shift encoding-based water-fat MRI of the lumbar spine was performed, and PDFF maps were calculated. Associations between fracture status and PDFF were assessed using multivariable linear regression models. RESULTS: Over all patients, mean PDFF and trabecular BMD correlated significantly (r = - 0.51, P < 0.001). In the osteoporotic/osteopenic group, those patients with osteoporotic/osteopenic fractures had a significantly higher PDFF than those without osteoporotic fractures after adjusting for age, sex, weight, height, and trabecular BMD (adjusted mean difference [95% confidence interval], 20.8% [10.4%, 30.7%]; P < 0.001), although trabecular BMD values showed no significant difference between the subgroups (P = 0.63). For the differentiation of patients with and without vertebral fractures in the osteoporotic/osteopenic subgroup using mean PDFF, an area under the receiver operating characteristic (ROC) curve (AUC) of 0.88 (P = 0.006) was assessed. When evaluating all patients with vertebral fractures, those with high-energy traumatic fractures had a significantly lower PDFF than those with low-energy osteoporotic/osteopenic vertebral fractures (P < 0.001). CONCLUSION: MR-based PDFF enables the differentiation between osteoporotic/osteopenic patients with and without vertebral fractures, suggesting the use of PDFF as a potential biomarker for bone fragility.
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Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Densidad Ósea , Médula Ósea/diagnóstico por imagen , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/etiología , Protones , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/etiologíaRESUMEN
PURPOSE: To evaluate diagnostic accuracy of fully automated analysis of multimodal imaging data using [18F]-FET-PET and MRI (including amide proton transfer-weighted (APTw) imaging and dynamic-susceptibility-contrast (DSC) perfusion) in differentiation of tumor progression from treatment-related changes in patients with glioma. MATERIAL AND METHODS: At suspected tumor progression, MRI and [18F]-FET-PET data as part of a retrospective analysis of an observational cohort of 66 patients/74 scans (51 glioblastoma and 23 lower-grade-glioma, 8 patients included at two different time points) were automatically segmented into necrosis, FLAIR-hyperintense, and contrast-enhancing areas using an ensemble of deep learning algorithms. In parallel, previous MR exam was processed in a similar way to subtract preexisting tumor areas and focus on progressive tumor only. Within these progressive areas, intensity statistics were automatically extracted from [18F]-FET-PET, APTw, and DSC-derived cerebral-blood-volume (CBV) maps and used to train a Random Forest classifier with threefold cross-validation. To evaluate contribution of the imaging modalities to the classifier's performance, impurity-based importance measures were collected. Classifier performance was compared with radiology reports and interdisciplinary tumor board assessments. RESULTS: In 57/74 cases (77%), tumor progression was confirmed histopathologically (39 cases) or via follow-up imaging (18 cases), while remaining 17 cases were diagnosed as treatment-related changes. The classification accuracy of the Random Forest classifier was 0.86, 95% CI 0.77-0.93 (sensitivity 0.91, 95% CI 0.81-0.97; specificity 0.71, 95% CI 0.44-0.9), significantly above the no-information rate of 0.77 (p = 0.03), and higher compared to an accuracy of 0.82 for MRI (95% CI 0.72-0.9), 0.81 for [18F]-FET-PET (95% CI 0.7-0.89), and 0.81 for expert consensus (95% CI 0.7-0.89), although these differences were not statistically significant (p > 0.1 for all comparisons, McNemar test). [18F]-FET-PET hot-spot volume was single-most important variable, with relevant contribution from all imaging modalities. CONCLUSION: Automated, joint image analysis of [18F]-FET-PET and advanced MR imaging techniques APTw and DSC perfusion is a promising tool for objective response assessment in gliomas.
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Neoplasias Encefálicas , Glioma , Imágenes de Resonancia Magnética Multiparamétrica , Amidas , Neoplasias Encefálicas/diagnóstico por imagen , Glioma/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Perfusión , Tomografía de Emisión de Positrones , Protones , Estudios Retrospectivos , TirosinaRESUMEN
Osteoporosis is a metabolic bone disease with a high prevalence that affects the population worldwide, particularly the elderly. It is often due to fractures associated with bone fragility that the diagnosis of osteoporosis becomes clinically evident. However, early diagnosis would be necessary to initiate therapy and to prevent occurrence of further fractures, thus reducing morbidity and mortality. X-ray-based imaging plays a key role for fracture risk assessment and monitoring of osteoporosis. Whereas over decades dual-energy X-ray absorptiometry (DXA) has been the main method used and still reflects the reference standard, another modality reemerges with quantitative computed tomography (QCT) because of its three-dimensional advantages and the opportunistic exploitation of routine CT scans. Against this background, this article intends to review and evaluate recent advances in the field of X-ray-based quantitative imaging of osteoporosis at the spine. First, standard DXA with the recent addition of trabecular bone score (TBS) is presented. Secondly, standard QCT, dual-energy BMD quantification, and opportunistic BMD screening in non-dedicated CT exams are discussed. Lastly, finite element analysis and microstructural parameter analysis are reviewed.
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Densidad Ósea , Osteoporosis , Absorciometría de Fotón , Anciano , Humanos , Osteoporosis/diagnóstico por imagen , Columna Vertebral , Rayos XRESUMEN
OBJECTIVE: To investigate whether T2 relaxation time measurements of cartilage repair tissue and structural changes of the knee joint are associated with subchondral bone architecture after spongiosa-augmented matrix-associated autologous chondrocyte implantation (MACI). DESIGN: Both knees of 25 patients (25.5 ± 7.8y; 10 women) were examined preoperatively and 2.7 years after unilateral spongiosa-augmented MACI with 3T magnetic resonance (MR) imaging. Cartilage composition was assessed using T2 relaxation time measurements, subchondral trabecular bone microstructure was quantified using a 3D phase-cycled balanced steady state free-precision sequence. Structural knee joint changes were assessed using the modified Whole-Organ Magnetic Resonance Imaging Score (WORMS). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was used for the postoperative description of the area that underwent MACI. Correlations were assessed using Spearman's rank correlation coefficients. RESULTS: Hypertrophy of the cartilage repair tissue was found in 2 of 25 patients, both after a MACI procedure at the patella, 21 patients showed congruent filling. In subchondral bone of the cartilage repair compartment, apparent trabecular thickness was significantly higher in compartments with elevated cartilage T2 (n = 17; 0.37 ± 0.05 mm) compared to those showing no difference in cartilage T2 compared to the same compartment in the contralateral knee (n = 8; 0.27 ± 0.05 mm; P = 0.042). Significant correlations were found between the overall progression of WORMS and the ipsilateral vs contralateral ratio of average trabecular thickness (r = 0.48, P = 0.031) and bone fraction (r = 0.57, P = 0.007). CONCLUSIONS: After spongiosa-augmented MACI, T2 values of cartilage repair tissue and structural knee joint changes correlated with the quality of the underlying trabecular bone.
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Remodelación Ósea/fisiología , Trasplante Óseo/métodos , Cartílago Articular/lesiones , Condrocitos/trasplante , Traumatismos de la Rodilla/cirugía , Adolescente , Adulto , Hueso Esponjoso/diagnóstico por imagen , Hueso Esponjoso/fisiopatología , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Femenino , Humanos , Traumatismos de la Rodilla/diagnóstico por imagen , Traumatismos de la Rodilla/fisiopatología , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Periodo Posoperatorio , Adulto JovenRESUMEN
Our study proposed an automatic pipeline for opportunistic osteoporosis screening using 3D texture features and regional vBMD using multi-detector CT images. A combination of different local and global texture features outperformed the global vBMD and showed high discriminative power to identify patients with vertebral fractures. INTRODUCTION: Many patients at risk for osteoporosis undergo computed tomography (CT) scans, usable for opportunistic (non-dedicated) screening. We compared the performance of global volumetric bone mineral density (vBMD) with a random forest classifier based on regional vBMD and 3D texture features to separate patients with and without osteoporotic fractures. METHODS: In total, 154 patients (mean age 64 ± 8.5, male; n = 103) were included in this retrospective single-center analysis, who underwent contrast-enhanced CT for other reasons than osteoporosis screening. Patients were dichotomized regarding prevalent vertebral osteoporotic fractures (noFX, n = 101; FX, n = 53). Vertebral bodies were automatically segmented, and trabecular vBMD was calculated with a dedicated phantom. For 3D texture analysis, we extracted gray-level co-occurrence matrix Haralick features (HAR), histogram of gradients (HoG), local binary patterns (LBP), and wavelets (WL). Fractured vertebrae were excluded for texture-feature and vBMD data extraction. The performance to identify patients with prevalent osteoporotic vertebral fractures was evaluated in a fourfold cross-validation. RESULTS: The random forest classifier showed a high discriminatory power (AUC = 0.88). Parameters of all vertebral levels significantly contributed to this classification. Importantly, the AUC of the proposed algorithm was significantly higher than that of volumetric global BMD alone (AUC = 0.64). CONCLUSION: The presented classifier combining 3D texture features and regional vBMD including the complete thoracolumbar spine showed high discriminatory power to identify patients with vertebral fractures and had a better diagnostic performance than vBMD alone.
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Osteoporosis/diagnóstico por imagen , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Anciano , Algoritmos , Densidad Ósea/fisiología , Estudios de Factibilidad , Femenino , Humanos , Imagenología Tridimensional/métodos , Hallazgos Incidentales , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/fisiopatología , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Estudios Retrospectivos , Fracturas de la Columna Vertebral/fisiopatología , Tomografía Computarizada por Rayos X/métodosRESUMEN
This feasibility study investigated the spatial heterogeneity of the lumbar vertebral bone marrow using chemical shift encoding-based water-fat MRI. Acquired texture features like contrast and dissimilarity allowed for differentiation of pre- and postmenopausal women and may serve as imaging biomarkers in the future. INTRODUCTION: While the vertebral bone marrow fat using chemical shift encoding water-fat magnetic resonance imaging (MRI) has been extensively studied, its spatial heterogeneity has not been analyzed yet. Therefore, this feasibility study investigated the spatial heterogeneity of the lumbar vertebral bone marrow by using texture analysis in proton density fat fraction (PDFF) maps. METHODS: Forty-one healthy pre- and postmenopausal women were recruited for this study (premenopausal (n = 15) 30 ± 7 years, postmenopausal (n = 26) 65 ± 7 years). An eight-echo 3D spoiled gradient echo sequence was used for chemical shift encoding-based water-fat separation at the lumbar spine. Vertebral bodies L1 to L5 were manually segmented. Mean PDFF values and texture features were extracted at each vertebral level, namely variance, skewness, and kurtosis, using statistical moments and second-order features (energy, contrast, correlation, homogeneity, dissimilarity, entropy, variance, and sum average). Parameters were compared between pre- and postmenopausal women and vertebral levels. RESULTS: PDFF was significantly higher in post- than in premenopausal women (49.37 ± 8.14% versus 27.76 ± 7.30%, p < 0.05). Furthermore, PDFF increased from L1 to L5 (L1 37.93 ± 12.85%, L2 38.81 ± 12.77%, L3 40.23 ± 12.72%, L4 42.80 ± 13.27%, L5 45.21 ± 14.55%, p < 0.05). Bone marrow heterogeneity based on texture analysis was significantly (p < 0.05) increased in postmenopausal women. Contrast and dissimilarity performed best in differentiating pre- and postmenopausal women (AUC = 0.97 and 0.96, respectively), not significantly different compared with PDFF (AUC = 0.97). CONCLUSION: Conclusively, an increased bone marrow heterogeneity could be observed in postmenopausal women. In the future, texture parameters might provide additional information to detect and monitor vertebral bone marrow alterations due to aging or hormonal changes beyond conventional anatomic imaging.
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Médula Ósea/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Tejido Adiposo/diagnóstico por imagen , Adulto , Anciano , Agua Corporal/diagnóstico por imagen , Estudios de Factibilidad , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/diagnóstico por imagen , Posmenopausia , PremenopausiaRESUMEN
This study investigated the feasibility of opportunistic osteoporosis screening in routine contrast-enhanced MDCT exams using texture analysis. The results showed an acceptable reproducibility of texture features, and these features could discriminate healthy/osteoporotic fracture cohort with an accuracy of 83%. INTRODUCTION: This aim of this study is to investigate the feasibility of opportunistic osteoporosis screening in routine contrast-enhanced MDCT exams using texture analysis. METHODS: We performed texture analysis at the spine in routine MDCT exams and investigated the effect of intravenous contrast medium (IVCM) (n = 7), slice thickness (n = 7), the long-term reproducibility (n = 9), and the ability to differentiate healthy/osteoporotic fracture cohort (n = 9 age and gender matched pairs). Eight texture features were extracted using gray level co-occurrence matrix (GLCM). The independent sample t test was used to rank the features of healthy/fracture cohort and classification was performed using support vector machine (SVM). RESULTS: The results revealed significant correlations between texture parameters derived from MDCT scans with and without IVCM (r up to 0.91) slice thickness of 1 mm versus 2 and 3 mm (r up to 0.96) and scan-rescan (r up to 0.59). The performance of the SVM classifier was evaluated using 10-fold cross-validation and revealed an average classification accuracy of 83%. CONCLUSIONS: Opportunistic osteoporosis screening at the spine using specific texture parameters (energy, entropy, and homogeneity) and SVM can be performed in routine contrast-enhanced MDCT exams.
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Tamizaje Masivo/métodos , Osteoporosis/diagnóstico por imagen , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Hueso Esponjoso/diagnóstico por imagen , Medios de Contraste , Estudios de Factibilidad , Femenino , Humanos , Hallazgos Incidentales , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodosRESUMEN
This study investigates the impact of tube current reduction and sparse sampling on femoral bone mineral density (BMD) measurements derived from multi-detector computed tomography (MDCT). The application of sparse sampling led to robust and clinically acceptable BMD measurements. In contrast, BMD measurements derived from MDCT with virtually reduced tube currents showed a considerable increase when compared to original data. INTRODUCTION: The study aims to evaluate the effects of radiation dose reduction by using virtual reduction of tube current or sparse sampling combined with standard filtered back projection (FBP) and statistical iterative reconstruction (SIR) on femoral bone mineral density (BMD) measurements derived from multi-detector computed tomography (MDCT). METHODS: In routine MDCT scans of 41 subjects (65.9% men; age 69.3 ± 10.1 years), reduced radiation doses were simulated by lowering tube currents and applying sparse sampling (50, 25, and 10% of the original tube current and projections, respectively). Images were reconstructed using FBP and SIR. BMD values were assessed in the femoral neck and compared between the different dose levels, numbers of projections, and image reconstruction approaches. RESULTS: Compared to full-dose MDCT, virtual lowering of the tube current by applying our simulation algorithm resulted in increases in BMD values for both FBP (up to a relative change of 32.5%) and SIR (up to a relative change of 32.3%). In contrast, the application of sparse sampling with a reduction down to 10% of projections showed robust BMD values, with clinically acceptable relative changes of up to 0.5% (FBP) and 0.7% (SIR). CONCLUSIONS: Our simulations, which still require clinical validation, indicate that reductions down to ultra-low tube currents have a significant impact on MDCT-based femoral BMD measurements. In contrast, the application of sparse-sampled MDCT seems a promising future clinical option that may enable a significant reduction of the radiation dose without considerable changes of BMD values.
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Densidad Ósea/fisiología , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/fisiopatología , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Algoritmos , Electricidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
Hidradenitis suppurativa/acne inversa (HS/AI) is a chronic inflammatory disease characterized by painful nodules, abscesses, fistulas, sinus tracts and scarring, which may lead to severe functional and psychological impairment. Patients often suffer for many years before the right diagnosis is finally made. HS/AI is still a therapeutic challenge. Conservative therapies play a role in mild stages of the disease; however they do not result in healing. Therapy of choice associated with the lowest recurrence rate is a radical wide excision of involved skin.
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Enfermedades del Ano/diagnóstico , Enfermedades del Ano/terapia , Hidradenitis Supurativa/diagnóstico , Hidradenitis/diagnóstico , Hidradenitis/terapia , Enfermedades del Ano/etiología , Hidradenitis/etiología , Hidradenitis Supurativa/terapia , Humanos , Recurrencia , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Tractography of the corticospinal tract is paramount to presurgical planning and guidance of intraoperative resection in patients with motor-eloquent gliomas. It is well-known that DTI-based tractography as the most frequently used technique has relevant shortcomings, particularly for resolving complex fiber architecture. The purpose of this study was to evaluate multilevel fiber tractography combined with functional motor cortex mapping in comparison with conventional deterministic tractography algorithms. MATERIALS AND METHODS: Thirty-one patients (mean age, 61.5 [SD, 12.2] years) with motor-eloquent high-grade gliomas underwent MR imaging with DWI (TR/TE = 5000/78 ms, voxel size = 2 × 2 × 2 mm3, 1 volume at b = 0 s/mm2, 32 volumes at b = 1000 s/mm2). DTI, constrained spherical deconvolution, and multilevel fiber tractography-based reconstruction of the corticospinal tract within the tumor-affected hemispheres were performed. The functional motor cortex was enclosed by navigated transcranial magnetic stimulation motor mapping before tumor resection and used for seeding. A range of angular deviation and fractional anisotropy thresholds (for DTI) was tested. RESULTS: For all investigated thresholds, multilevel fiber tractography achieved the highest mean coverage of the motor maps (eg, angular threshold = 60°; multilevel/constrained spherical deconvolution/DTI, 25% anisotropy threshold = 71.8%, 22.6%, and 11.7%) and the most extensive corticospinal tract reconstructions (eg, angular threshold = 60°; multilevel/constrained spherical deconvolution/DTI, 25% anisotropy threshold = 26,485 mm3, 6308 mm3, and 4270 mm3). CONCLUSIONS: Multilevel fiber tractography may improve the coverage of the motor cortex by corticospinal tract fibers compared with conventional deterministic algorithms. Thus, it could provide a more detailed and complete visualization of corticospinal tract architecture, particularly by visualizing fiber trajectories with acute angles that might be of high relevance in patients with gliomas and distorted anatomy.
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Neoplasias Encefálicas , Glioma , Corteza Motora , Humanos , Persona de Mediana Edad , Tractos Piramidales/diagnóstico por imagen , Tractos Piramidales/patología , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/patología , Imagen de Difusión Tensora/métodos , Corteza Motora/patología , Glioma/diagnóstico por imagen , Glioma/cirugía , Glioma/patologíaRESUMEN
Imaging of the postoperative spine intends to answer two main questions: It is used to assess the surgical success and to identify complications. To this end, conventional Xray, computer tomography (CT), myelography, and magnetic resonance imaging (MRI) are available. The radiologist has to select the appropriate modality for sufficient diagnosis considering the preoperative situation, the performed operation, and existing postoperative symptoms. Particularly, the implantation of foreign material represents a technical challenge in the context of image acquisition. In the radiologist's report, one must differentiate between expected postoperative changes and relevant complications. Close communication with the patients and the referring clinicians is essential. Especially clinical signs of infection, new or progressive neurological deficits and cauda equina and conus medullaris syndromes require an immediate diagnosis to facilitate prompt therapy.
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Cauda Equina , Columna Vertebral , Tomografía Computarizada por Rayos X , Cauda Equina/cirugía , Humanos , Sistema Musculoesquelético/diagnóstico por imagen , Mielografía , Compresión de la Médula Espinal/diagnóstico , Columna Vertebral/diagnóstico por imagenRESUMEN
Fingolimod and natalizumab are approved disease-modifying drugs in relapsing-remitting multiple sclerosis (RRMS). The two drugs have different modes of action and may therefore influence different aspects of MS-related tissue damage. In this retrospective cohort study, we longitudinally compared patients treated with fingolimod and patients treated with natalizumab by measures based on structural magnetic resonance imaging (MRI). We included patients with RRMS given that two standardized MRI scans under the same drug were available with an interval of at least 6 months both from therapy start to baseline scan and from baseline scan to follow-up scan. After matching for age, baseline and follow-up scans from 93 patients (fingolimod, 48; natalizumab, 45) were investigated. Mean follow-up time was 1.9 years. We determined the number of new white matter lesions as well as thalamic, cortical, and whole-brain atrophy. After scaling for time of the interscan interval, measures were analyzed by group comparisons and, to account for demographic and clinical characteristics, by multiple regression models and a binary logistic regression model. Compared to natalizumab, fingolimod treatment went along with more new white matter lesions (median [interquartile range, IQR] 0.0 [0.0; 0.7] vs. 0.0 [0.0; 0.0] /year; p < 0.01) whereas whole-brain atrophy was lower (median [IQR] 0.2 [0.0; 0.5] vs. 0.5 [0.2; 1.0] %/year; p = 0.01). These significant differences were confirmed by multiple regression models and the binary logistic regression model. In conclusion, our observation is compatible with stronger neuroprotective properties of fingolimod compared to natalizumab.
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Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Clorhidrato de Fingolimod/uso terapéutico , Humanos , Factores Inmunológicos/uso terapéutico , Inmunosupresores/uso terapéutico , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/patología , Natalizumab/uso terapéutico , Estudios RetrospectivosRESUMEN
PURPOSE: Through analysis of T1-weighted (T1w) images this study investigated gadolinium (Gd) deposition in the brain after administration of a linear (gadopentetic acid) and a cyclic (gadoteric acid) gadolinium-based contrast agent (GBCA) in patients with multiple sclerosis (MS), a disorder frequently requiring magnetic resonance imaging (MRI) scans over years. METHODS: A total of 3233 T1w images (unenhanced with respect to the same scanning session) of 881 MS patients were retrospectively analyzed. After spatial normalization and intensity scaling using a sphere within the pons, differences of all pairs of subsequent scans were calculated and attributed to either linear (nâ¯= 2718) or cyclic (nâ¯= 385) or no GBCA (nâ¯= 130) according to the first scan. Regional analyses were performed, focusing on the dentate nucleus, and whole brain analyses. By 1sample ttests, signal intensity increases within conditions were searched for; conditions were compared by 2sample ttests. Furthermore, recent hypotheses on the reversibility of GBCA deposition were tested. RESULTS: In the dentate nucleus, a significant increase was observed only after administration of linear GBCA even after a single GBCA administration. This increase differed significantly (pâ¯< 0.001) from the other conditions (cyclic and no GBCA). Whole brain analyses revealed T1w signal increases only after administration of linear GBCA within two regions, the dentate nucleus and globus pallidus. Additional analyses did not indicate any decline of Gd deposition in the brain. CONCLUSION: The data point towards Gd deposition in the brain after administration of linear GBCA even after a single administration.
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Esclerosis Múltiple , Compuestos Organometálicos , Medios de Contraste , Femenino , Gadolinio , Gadolinio DTPA , Humanos , Imagen por Resonancia Magnética , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/tratamiento farmacológico , Estudios RetrospectivosRESUMEN
BACKGROUND: The historical development of interventional stroke treatment shows a wide variation of different techniques and materials used. Thus, the question of the present work is whether the technical and procedural differences of thrombectomy techniques lead to different technical and clinical results. METHODS AND RESULTS: Analysis of a mixed retrospective/prospective database of all endovascular treated patients with an occlusion of the Carotid-T or M1 segment of the MCA at a single comprehensive stroke center since 2008. Patients were classified regarding the technical approach used. Six hundred sixty-eight patients were available for the final analysis. Reperfusion rates ranged between 56% and 100% depending on the technical approach. The use of balloon guide catheters and most recently the establishment of combination techniques using balloon guide catheters, aspiration catheters and stent retrievers have shown a further significant increase in the rates of successful recanalization, full recanalization and first-pass recanalization. Additionally, the technical development of interventional techniques has led to a subsequent drop in complications, embolization into previously unaffected territories in particular. CONCLUSION: Technical success of MT has improved substantially over the past decade owing to improved materials and procedural innovations. Combination techniques including flow modulation have emerged to be the most effective approach and should be considered as a standard of care.Level of evidence: Level 3, retrospective study.
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Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Estudios Retrospectivos , Stents , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/cirugía , Trombectomía , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: A 3D T1-weighted black-blood sequence was recently shown to improve the detection of contrast-enhancing lesions in the brain in patients with MS compared with a 3D T1-weighted MPRAGE sequence. We compared a contrast-enhanced 3D T1-weighted black-blood sequence with a dedicated orbital contrast-enhanced T1-weighted Dixon sequence in patients with acute optic neuritis. MATERIALS AND METHODS: MR imaging data (3T) of 51 patients showing symptoms of acute optic neuritis were analyzed retrospectively, including whole-brain contrast-enhanced 3D T1-weighted black-blood and dedicated orbital coronal 2D or 3D contrast-enhanced T1-weighted Dixon sequences. Two neuroradiologists assessed the images for overall image quality, artifacts, diagnostic confidence, and visual contrast enhancement. Furthermore, the standardized contrast-to-noise ratio was calculated. The final diagnosis of acute optic neuritis was established on the basis of clinical presentation, visually evoked potentials, and optical coherence tomography. RESULTS: Thirty of 51 patients were diagnosed with acute optic neuritis. Of those, 21 showed contrast-enhancing lesions in the optic nerves, similarly detectable on contrast-enhanced T1-weighted Dixon and contrast-enhanced T1-weighted black-blood images. Thus, the accuracy for each sequence was identical, with a resulting sensitivity of 70% and specificity of 90% or 100% (depending on the reader). Overall image quality, diagnostic confidence, visual contrast enhancement, and artifacts were rated similarly in contrast-enhanced 3D T1-weighted black-blood and dedicated orbital contrast-enhanced T1-weighted Dixon sequences. There was no significant difference (P = .27) in the mean standardized contrast-to-noise ratio between contrast-enhanced T1-weighted black-blood (1.76 ± 1.07) and contrast-enhanced T1-weighted Dixon (2.29 ± 2.49) sequences. CONCLUSIONS: Contrast-enhanced 3D T1-weighted black-blood imaging is comparable in accuracy and qualitative/quantitative features with dedicated orbital contrast-enhanced T1-weighted Dixon imaging for the detection of acute optic neuritis. Therefore, when used, it has the potential to considerably shorten total patient imaging time.
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Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Neuritis Óptica/diagnóstico por imagen , Adolescente , Adulto , Anciano , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: The number of white matter lesions (WML) in brain MRI is the most established paraclinical tool to support the diagnosis of multiple sclerosis (MS) and to monitor its course. Diagnostic criteria have stipulated a minimum detectable diameter of 3 mm per WML, although this threshold is not evidence-based. We aimed to provide a rationale for a WML size threshold for three-dimensional MRI sequences at 3 T by comparing patients with relapsing-remitting MS (RRMS) to control subjects (CS). METHODS: We analyzed MR images from two cohorts, obtained at scanners from two different vendors, each comprising patients with RRMS and CS. Both cohorts were examined with FLAIR and T1w sequences. In total, 232 patients with RRMS (Expanded Disability Status Scale: meanâ¯=â¯1.6 ± 1.2; age: mean = 36 ± 10) as well as 116 age- and sex-matched CS were studied. We calculated odds ratios across WML volumes. The WML size threshold, which discriminated best between patients and CS, was estimated with receiver operating characteristic curve analysis. RESULTS: In both cohorts, odds ratios increased continuously with increasing WML volumes, and discriminative power was highest at a WML size threshold corresponding to a diameter of about 3 mm. CONCLUSION: The stipulated WML size threshold of 3 mm in diameter for the diagnostic criteria of MS seems a reasonable choice for three-dimensional MRI sequences at 3 T.
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Imagen por Resonancia Magnética/normas , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Neuroimagen/normas , Sustancia Blanca/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Esclerosis Múltiple Recurrente-Remitente/patología , Estándares de Referencia , Estudios Retrospectivos , Sustancia Blanca/patología , Adulto JovenRESUMEN
BACKGROUND AND PURPOSE: The double inversion recovery sequence is known to be very sensitive and specific for MS-related lesions. Our aim was to compare the sensitivity of pre- and postcontrast images of 3D double inversion recovery and conventional 3D T1-weighted images for the detection of contrast-enhancing MS-related lesions in the brain to analyze whether double inversion recovery could be as effective as T1WI. MATERIALS AND METHODS: A postcontrast 3D double inversion recovery sequence was acquired in addition to the standard MR imaging protocol at 3T, including pre- and postcontrast 3D T1WI sequences as well as precontrast double inversion recovery of 45 consecutive patients with MS or clinically isolated syndrome between June and December 2013. Two neuroradiologists independently assessed precontrast, postcontrast, and subtraction images of double inversion recovery as well as T1WI to count the number of contrast-enhancing lesions. Afterward, a consensus reading was performed. Lin concordance was calculated between both radiologists, and differences in lesion detectability were assessed with the Student t test. Additionally, the contrast-to-noise ratio was calculated. RESULTS: Significantly more contrast-enhancing lesions could be detected with double inversion recovery compared with T1WI (16%, 214 versus 185, P = .007). The concordance between both radiologists was almost perfect (ρc = 0.94 for T1WI and ρc = 0.98 for double inversion recovery, respectively). The contrast-to-noise ratio was significantly higher in double inversion recovery subtraction images compared with T1-weighted subtraction images (double inversion recovery, 14.3 ± 5.5; T1WI, 6.3 ± 7.1; P < .001). CONCLUSIONS: Pre- and postcontrast double inversion recovery enables better detection of contrast-enhancing lesions in MS in the brain compared with T1WI and may be considered an alternative to the standard MR imaging protocol.
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Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/diagnóstico por imagen , Neuroimagen/métodos , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/patología , Sensibilidad y Especificidad , Adulto JovenRESUMEN
AIMS: We aimed to retrospectively assess the accuracy and safety of CT navigated pedicle screws and to compare accuracy in the cervical and thoracic spine (C2-T8) with (COMB) and without (POST) prior anterior surgery (anterior cervical discectomy or corpectomy and fusion with ventral plating: ACDF/ACCF). PATIENTS AND METHODS: A total of 592 pedicle screws, which were used in 107 consecutively operated patients (210 COMB, 382 POST), were analysed. The accuracy of positioning was determined according to the classification of Gertzbein and Robbins on post-operative CT scans. RESULTS: High accuracy was achieved in 524 screws (88.5%), 192 (87.7%) in the cervical spine and 332 (89%) in the thoracic spine, respectively. The results in the two surgical groups were compared and a logistic regression mixed model was performed to analyse the risk of low accuracy. Significantly lower accuracy was found in the COMB group with 82.9% versus 91.6% in the POST group (p = 0.036). There were no neurological complications, but two vertebral artery lesions were recorded. Three patients underwent revision surgery for malpositioning of a screw. Although the risk of malpositioning of a screw after primary anterior surgery was estimated to be 2.4-times higher than with posterior surgery alone, the overall rates of complication and revision were low. CONCLUSION: We therefore conclude that CT navigated pedicle screws can be positioned safely although greater caution must be taken in patients who have previously undergone anterior surgery. Cite this article: Bone Joint J 2017;99-B:1373-80.
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Vértebras Cervicales/cirugía , Desplazamiento del Disco Intervertebral/cirugía , Tornillos Pediculares , Fusión Vertebral/métodos , Cirugía Asistida por Computador/métodos , Vértebras Torácicas/cirugía , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Placas Óseas , Vértebras Cervicales/diagnóstico por imagen , Femenino , Humanos , Desplazamiento del Disco Intervertebral/diagnóstico , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Vértebras Torácicas/diagnóstico por imagen , Adulto JovenRESUMEN
The cerebral cortex is a highly folded outer layer of grey matter tissue that plays a key role in cognitive functions. In part, alterations of the cortex during development and disease can be captured by measuring the cortical thickness across the whole brain. Available software tools differ with regard to labor intensity and computational demands. In this study, we compared the computational anatomy toolbox (CAT), a recently proposed volume-based tool, with the well-established surface-based tool FreeSurfer. We observed that overall thickness measures were highly inter-correlated, although thickness estimates were systematically lower in CAT than in FreeSurfer. Comparison of multiple sclerosis (MS) patients with age-matched healthy control subjects showed highly comparable clusters of MS-related thinning for both methods. Likewise, both methods yielded comparable clusters of age-related cortical thinning, although correlations between age and average cortical thickness were stronger for FreeSurfer. Our data suggest that, for the analysis of cortical thickness, the volume-based CAT tool can be regarded a considerable alternative to the well-established surface-based FreeSurfer tool.