scholarly journals De‐identification procedures for magnetic resonance images and the impact on structural brain measures at different ages

2021 ◽  
Author(s):  
Elizabeth E. L. Buimer ◽  
Hugo G. Schnack ◽  
Yaron Caspi ◽  
Neeltje E. M. Haren ◽  
Mikhail Milchenko ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Images ◽  
Different Ages ◽  
The Impact ◽  
Structural Brain ◽  
Identification Procedures

scholarly journals Multigrid Nonlocal Gaussian Mixture Model for Segmentation of Brain Tissues in Magnetic Resonance Images

2016 ◽  
Vol 2016 ◽  
pp. 1-10
Author(s):  
Yunjie Chen ◽  
Tianming Zhan ◽  
Ji Zhang ◽  
Hongyuan Wang
Keyword(s):  
Magnetic Resonance ◽  
Gaussian Mixture Model ◽  
Mixture Model ◽  
Gaussian Mixture ◽  
Magnetic Resonance Images ◽  
Intensity Inhomogeneity ◽  
Mr Images ◽  
Proposed Model ◽  
Brain Mr Images ◽  
The Impact

We propose a novel segmentation method based on regional and nonlocal information to overcome the impact of image intensity inhomogeneities and noise in human brain magnetic resonance images. With the consideration of the spatial distribution of different tissues in brain images, our method does not need preestimation or precorrection procedures for intensity inhomogeneities and noise. A nonlocal information based Gaussian mixture model (NGMM) is proposed to reduce the effect of noise. To reduce the effect of intensity inhomogeneity, the multigrid nonlocal Gaussian mixture model (MNGMM) is proposed to segment brain MR images in each nonoverlapping multigrid generated by using a new multigrid generation method. Therefore the proposed model can simultaneously overcome the impact of noise and intensity inhomogeneity and automatically classify 2D and 3D MR data into tissues of white matter, gray matter, and cerebral spinal fluid. To maintain the statistical reliability and spatial continuity of the segmentation, a fusion strategy is adopted to integrate the clustering results from different grid. The experiments on synthetic and clinical brain MR images demonstrate the superior performance of the proposed model comparing with several state-of-the-art algorithms.

scholarly journals Effects of gestational age at birth on perinatal structural brain development in healthy term-born babies

2021 ◽  
Author(s):  
Oliver Gale-Grant ◽  
Sunniva Fenn-Moltu ◽  
Lucas Franca ◽  
Ralica Dimitrova ◽  
Daan Christiaens ◽  
...  
Keyword(s):  
Linear Regression ◽  
Gestational Age ◽  
Neurodevelopmental Outcome ◽  
Magnetic Resonance Images ◽  
Linear Regression Models ◽  
Early Term ◽  
Gestational Age At Birth ◽  
The Impact ◽  
Age At Birth ◽  
Structural Brain

Multiple studies have demonstrated less favourable childhood outcomes in infants born in early term (37-38 weeks gestation) compared to those born at full term (40-41 weeks gestation). While this could be due to lower birthweight and greater perinatal morbidity, gestational age at birth may also have a direct effect on the brain and subsequent neurodevelopment in term-born babies. Here we characterise structural brain correlates of gestational age at birth in healthy term-born neonates and their relationship to later neurodevelopmental outcome. We used T2 and diffusion weighted Magnetic Resonance Images acquired in the neonatal period from a cohort (n=454) of healthy babies born at term age (>37 weeks gestation) and scanned between 1 and 41 days after birth. Images were analysed using tensor based morphometry (TBM) and tract based spatial statistics (TBSS). Neurodevelopment was subsequently assessed at age 18 months using the Bayley-III Scales of Infant and Toddler Development (n=281), and the effects of gestational age at birth and related neuroimaging findings on outcome were analysed with linear regression. Infants born earlier had areas of higher relative ventricular volume, and lower relative brain volume in the basal ganglia, cerebellum and brainstem. Earlier birth was also associated with lower fractional anisotropy, higher mean, axial and radial diffusivity in major white matter tracts. Gestational age at birth was positively associated with all Bayley-III subscales at age 18 months. Linear regression models predicting outcome from gestational age at birth were significantly improved by adding neuroimaging features associated with gestational age at birth. This work adds to the growing body of evidence of the impact of early term birth and highlights the importance of considering the effect of gestational age at birth in future neuroimaging studies including term-born babies.

Stagnant Venous Outflow Predicts Brain Arteriovenous Malformation Obliteration After Gamma Knife Radiosurgery Without Prior Intervention

Neurosurgery ◽  
2019 ◽  
Vol 87 (2) ◽  
pp. 338-347 ◽  
Author(s):  
Yong-Sin Hu ◽  
Cheng-Chia Lee ◽  
Hsiu-Mei Wu ◽  
Huai-Che Yang ◽  
Te-Ming Lin ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Digital Subtraction Angiography ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
Magnetic Resonance Images ◽  
Venous Stasis ◽  
Digital Subtraction ◽  
Venous Outflow ◽  
Therapeutic Decisions ◽  
The Impact

Abstract BACKGROUND Gamma Knife radiosurgery (GKRS) obliterates 65% to 82% of brain arteriovenous malformations (BAVMs). OBJECTIVE To explore the impact of hemodynamics on GKRS outcomes. METHODS We retrospectively (2011-2017) included 98 patients with BAVMs who had received GKRS alone. Two evaluators, blinded to the outcomes, analyzed the pre-GKRS angiography and magnetic resonance images to obtain the morphological characteristics and quantitative digital subtraction angiography (QDSA) parameters. The venous stasis index was defined as the inflow gradient divided by the absolute value of the outflow gradient. Patients’ follow-up magnetic resonance or digital subtraction angiography images were evaluated for the presence of complete obliteration (CO). Cox regression and Kaplan–Meier analyses were conducted to determine the correlations between the parameters and outcomes. RESULTS Among the 98 patients, 63 (63.4%) achieved CO after GKRS at a median latency period of 31 mo. In multivariable analyses with adjustments for age and sex, increased BAVM volume (hazard ratio (HR) 0.949, P = .022) was an independent characteristic predictor, and venous stenosis (HR 2.595, P = .009), venous rerouting (HR 0.375, P = .022), and larger stasis index (HR 1.227, P = .025) were independent angiographic predictors of CO. BAVMs with a stasis index of >1.71 had a higher 36-mo probability of CO than those with a stasis index of ≤1.71 (61.1% vs 26.7%, P < .001). CONCLUSION BAVMs with a larger stasis index, indicating more stagnant venous outflow, may predict obliteration after GKRS. QDSA analysis may help in predicting BAVM treatment outcomes and making therapeutic decisions.

scholarly journals Complex Meniscus Tears Treated with Collagen Matrix Wrapping and Bone Marrow Blood Injection: Clinical Effectiveness and Survivorship after a Minimum of 5 Years’ Follow-Up

Cartilage ◽  
2020 ◽  
pp. 194760352092476 ◽  
Author(s):  
Kinga Ciemniewska-Gorzela ◽  
Paweł Bąkowski ◽  
Jakub Naczk ◽  
Roland Jakob ◽  
Tomasz Piontek
Keyword(s):  
Bone Marrow ◽  
Survival Rate ◽  
Magnetic Resonance ◽  
Acl Reconstruction ◽  
Magnetic Resonance Images ◽  
Meniscus Repair ◽  
Blood Injection ◽  
The Impact ◽  
Bone Marrow Blood

Purpose. To determine the 5-year success rate of the “all-inside” technique of arthroscopic meniscus suture and collagen membrane wrapping along with bone marrow blood injection, to evaluate the progression of degenerative changes and the impact of simultaneous anteriro cruciate ligament (ACL) reconstruction. Methods. Fifty-four consecutive patients with complex meniscal tears were treated with the previously described technique. The subjective scores (International Knee Documentation Committee 2000, Lysholm, EQ-5D-5L) and Barret clinical criteria of meniscal healing were recorded. Magnetic resonance images (MRIs) were assessed at 2 and 5 years postoperatively, using the Whole-Organ Magnetic Resonance Imaging Score (WORMS) criteria. Kaplan-Meier survival analyses were performed in order to assess the survivorship after the index procedure. Thirty-nine patients were divided into 2 groups: group A—isolated meniscus repair and group B—meniscus repair with concurrent ACL reconstruction. Results. Fifty-four patients were treated and 44 were available for analysis. There was a statistically significant improvement in subjective scores and clinical assessment between the preoperative, 2-year follow-up, and 5-year follow-up time points. EQ-5D-5L utility value was 0.9 ± 1 at final follow-up. The WORMS osteoarthritis severity grade had increased from 6.9 ± 5.0 points at the 2-year follow-up to 11.1 ± 9.6 points at the 5-year follow-up ( P < 0.001). There was a significant difference between the groups after 60 months. The overall survival rate at final follow-up was 88%. Conclusions. The treatment option evaluated in this study has shown very good mid-term clinical and MRI-based outcomes as well as a favorable survival rate. Simultaneous ACL reconstruction is likely a factor for osteoarthritis progression.

scholarly journals The significance of NNT parameter for the evaluation of therapy effectiveness

2016 ◽  
Vol 16 (4) ◽  
pp. 175-179
Author(s):  
Andrzej Potemkowski ◽  
Keyword(s):  
Multiple Sclerosis ◽  
Health Care ◽  
Clinical Trial ◽  
Magnetic Resonance ◽  
Magnetic Resonance Images ◽  
Disability Progression ◽  
Advantages And Disadvantages ◽  
Number Of Patients ◽  
Clinical Trial Results ◽  
The Impact

Clinical trials provide a practicing clinician with an abundance if not excess of data to draw on when comparing treatment methods and deciding the potentially optimal therapeutic option for a given patient. NNT, or number needed to treat, has been identified as one of the parameters useful for assessing the effectiveness of therapy. It represents the number of patients who must undergo a given health-care intervention instead of another one to see a difference in the effectiveness of obtaining a desired outcome within a set timeframe. NNT is a derivative of absolute risk reduction (ARR) or initial risk and its relative reduction. It represents the relative superiority of a given treatment. NNT is primarily used for comparing the advantages and disadvantages of alternative health-care interventions, and its assessment is important for estimating the clinical value of statistically significant clinical trial results. Utilization of NNT allows to predict therapy outcome both in terms of its effectiveness and tolerance. Also, clinical trial results presented in the form of NNT may be easily shared with patients, their families, and the institutions deciding the availability of a given drug. In multiple sclerosis, clinical trial results have been concerned with the impact of therapeutics on decrease of annualized relapse rate (ARR) and reduction of lesions visible in magnetic resonance images as well as slowing of disability progression. Analyses of first-line multiple sclerosis treatments reveal their NNT referred to prevention of relapses, disability progression and lesions in magnetic resonance image to vary significantly. Similar differences exist across NNT values established for second-line treatments or the oral therapies being currently introduced. The data clearly show that when evaluating clinical trial results, it is not enough to consider only given parameters, as they must all be critically and constructively analysed. NNT’s importance is also stressed as a clear parameter to be used for the evaluation of economic outcomes in healthcare.

scholarly journals Standardized quality metric system for structural brain magnetic resonance images in multi-center neuroimaging study

2018 ◽  
Vol 18 (1) ◽  
Author(s):  
Michael E. Osadebey ◽  
Marius Pedersen ◽  
Douglas L. Arnold ◽  
Katrina E. Wendel-Mitoraj ◽  
for the Alzheimer’s Disease Neuroimaging In
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Images ◽  
Quality Metric ◽  
Neuroimaging Study ◽  
Structural Brain

scholarly journals The impact of preoperative magnetic resonance images on outcome of cemented vertebrae

2010 ◽  
Vol 19 (11) ◽  
pp. 1899-1906 ◽  
Author(s):  
Wei-Che Lin ◽  
Cheng-Hsien Lu ◽  
Hsiu-Ling Chen ◽  
Hung-Chen Wang ◽  
Chun-Yen Yu ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Images ◽  
Preoperative Magnetic Resonance ◽  
The Impact

scholarly journals A methodology to investigate the impact of image distortions on the radiation dose when using magnetic resonance images for planning

2018 ◽  
Vol 63 (8) ◽  
pp. 085005 ◽  
Author(s):  
Yue Yan ◽  
Jinzhong Yang ◽  
Sam Beddar ◽  
Geoffrey Ibbott ◽  
Zhifei Wen ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Radiation Dose ◽  
Magnetic Resonance Images ◽  
The Impact
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