scholarly journals STEREOLOGICAL EVALUATION OF BRAIN MAGNETIC RESONANCE IMAGES OF SCHIZOPHRENIC PATIENTS

2013 ◽  
Vol 32 (3) ◽  
pp. 145
Author(s):  
Amani Abdelrazag Elfaki ◽  
Abdelrazag Elfaki ◽  
Tahir Osman ◽  
Bunyamin Sahin ◽  
Abdelgani Elsheikh ◽  
...  
Keyword(s):  
White Matter ◽  
Magnetic Resonance ◽  
Structural Changes ◽  
Volume Fraction ◽  
Brain Structures ◽  
Magnetic Resonance Images ◽  
Brain Images ◽  
Schizophrenic Patients ◽  
The Mean ◽  
Mr Brain

Advances in neuroimaging have enabled studies of specific neuroanatomical abnormalities with relevance to schizophrenia. This study quantified structural alterations on brain magnetic resonance (MR) images of patients with schizophrenia. MR brain imaging was done on 88 control and 57 schizophrenic subjects and Dicom images were analyzed with ImageJ software. The brain volume was estimated with the planimetric stereological technique. The volume fraction of brain structures was also estimated. The results showed that, the mean volume of right, left, and total hemispheres in controls were 551, 550, and 1101 cm³, respectively. The mean volumes of right, left, and total hemispheres in schizophrenics were 513, 512, and 1026 cm³, respectively. The schizophrenics’ brains were smaller than the controls (p < 0.05). The mean volume of total white matter of controls (516 cm³) was bigger than the schizophrenics’ volume (451 cm³), (p < 0.05). The volume fraction of total white matter was also lower in schizophrenics (p < 0.05). Volume fraction of the lateral ventricles was higher in schizophrenics (p < 0.05). According to the findings, the volumes of schizophrenics’ brain were smaller than the controls and the volume fractional changes in schizophrenics showed sex dependent differences. We conclude that stereological analysis of MR brain images is useful for quantifying schizophrenia related structural changes.

scholarly journals MAP–Based Framework for Segmentation of MR Brain Images Based on Visual Appearance and Prior Shape

2013 ◽  
Author(s):  
Amir Alansary ◽  
Ahmed Soliman ◽  
Fahmi Khalifa ◽  
Ahmed Elnakib ◽  
Mahmoud Mostapha ◽  
...  
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Empirical Distribution ◽  
Brain Structures ◽  
Shape Prior ◽  
Unsupervised Segmentation ◽  
Brain Images ◽  
Visual Appearance ◽  
Mr Brain Images ◽  
Mr Brain

We propose a new MAP-based technique for the unsupervised segmentation of different brain structures (white matter, gray matter, etc.) from T1-weighted MR brain images. In this paper, we follow a procedure like most conventional approaches, in which T1-weighted MR brain images and desired maps of regions (white matter, gray matter, etc.) are modeled by a joint Markov-Gibbs Random Field model (MGRF) of independent image signals and interdependent region labels. However, we specifically focus on the most accurate model identification that can be achieved. The proposed joint MGRF model accounts for the following three descriptors: i) a 1st-order visual appearance descriptor(empirical distribution of signal intensity), ii) a 3D probabilistic shape prior, and iii) a 3D spatially invariant 2nd-order homogeneity descriptor. To better specify the 1st-order visual appearance descriptor, each empirical distribution of signals is precisely approximated by a Linear Combination of Discrete Gaussians (LCDG) having both positive and negative components. The 3D probabilistic shape prior is learned using a subset of 3D co-aligned training T1-weighted MR brain images. The 2nd-order homogeneity descriptor is modeled by a 2nd-order translation and rotation invariant MGRF of 3D T1-weighted MR brain region labels with analytically estimated potentials. The initial segmentation, based on a 1st-order visual appearance and 3D probabilistic shape, is then iteratively refined using a 3D MGRF model with analytically estimated potentials. Experiments on twelve 3D T1-weighted MR brain images confirm the high accuracy of the proposed approach.

Brain Structural Magnetic Resonance Imaging for Joint Independent Component Analysis in Schizophrenic Patients

2019 ◽  
Vol 15 (5) ◽  
pp. 471-478
Author(s):  
Wen-Lin Chu ◽  
Min-Wei Huang ◽  
Bo-Lin Jian ◽  
Kuo-Sheng Cheng
Keyword(s):  
Magnetic Resonance Imaging ◽  
White Matter ◽  
Magnetic Resonance ◽  
Independent Component Analysis ◽  
Component Analysis ◽  
Independent Component ◽  
Resonance Imaging ◽  
Brain Images ◽  
Schizophrenic Patients ◽  
Normal Controls

Background: In past magnetic resonance imaging studies, normal participants and schizophrenia patients have usually been compared using imaging processing modes with only one parameter. A more extensive evaluation of significant differences between gray and white matter in Schizophrenic patents was necessary. Methods: Voxel based morphometry was used to separate brain images into gray matter and white matter. Then, the images were mapped to Montreal Neurological Institute space, and DARTEL analytic template was applied for image calibration with statistical parametric mapping. Finally, joint independent component analysis was employed to analyze the gray and white matter of brain images from Schizophrenic patients and normal controls. In this study, joint independent component analysis was used to discriminate clinical differences in magnetic resonance imaging signals between Schizophrenic patients and normal controls. Results: Region of interest analyses has repeatedly shown gray matter reduction in the superior temporal gyrus of Schizophrenic patients. Conclusion: These results strongly support previous studies regarding brain volume in schizophrenic patients. The connection networks in frontal and temporal lobes evidently did not differ between normal participants and schizophrenia patients.

scholarly journals Automated Head Tissue Modelling Based on Structural Magnetic Resonance Images for Electroencephalographic Source Reconstruction

2021 ◽  
Author(s):  
Gaia Amaranta Taberna ◽  
Jessica Samogin ◽  
Dante Mantini
Keyword(s):  
Magnetic Resonance ◽  
Brain Structures ◽  
Magnetic Resonance Images ◽  
Head Model ◽  
Source Reconstruction ◽  
Mr Images ◽  
Tissue Segmentation ◽  
Mr Image ◽  
Eeg Recordings ◽  
Tissue Modelling

AbstractIn the last years, technological advancements for the analysis of electroencephalography (EEG) recordings have permitted to investigate neural activity and connectivity in the human brain with unprecedented precision and reliability. A crucial element for accurate EEG source reconstruction is the construction of a realistic head model, incorporating information on electrode positions and head tissue distribution. In this paper, we introduce MR-TIM, a toolbox for head tissue modelling from structural magnetic resonance (MR) images. The toolbox consists of three modules: 1) image pre-processing – the raw MR image is denoised and prepared for further analyses; 2) tissue probability mapping – template tissue probability maps (TPMs) in individual space are generated from the MR image; 3) tissue segmentation – information from all the TPMs is integrated such that each voxel in the MR image is assigned to a specific tissue. MR-TIM generates highly realistic 3D masks, five of which are associated with brain structures (brain and cerebellar grey matter, brain and cerebellar white matter, and brainstem) and the remaining seven with other head tissues (cerebrospinal fluid, spongy and compact bones, eyes, muscle, fat and skin). Our validation, conducted on MR images collected in healthy volunteers and patients as well as an MR template image from an open-source repository, demonstrates that MR-TIM is more accurate than alternative approaches for whole-head tissue segmentation. We hope that MR-TIM, by yielding an increased precision in head modelling, will contribute to a more widespread use of EEG as a brain imaging technique.

scholarly journals Neuroanatomy and Volumes of Brain Structures of a Live California Sea Lion (Zalophus californianus) From Magnetic Resonance Images

2009 ◽  
Vol 292 (10) ◽  
pp. 1523-1547 ◽  
Author(s):  
Eric W. Montie ◽  
Nicola Pussini ◽  
Gerald E. Schneider ◽  
Thomas W.K. Battey ◽  
Sophie Dennison ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Brain Structures ◽  
Magnetic Resonance Images ◽  
Zalophus Californianus ◽  
Sea Lion ◽  
California Sea Lion

T2 hyperintense foci on magnetic resonance images of schizophrenic patients and controls

1991 ◽  
Vol 40 (4) ◽  
pp. 239-245 ◽  
Author(s):  
George Bartzokis ◽  
H.Jordan Garber ◽  
Virginia J. Griswold ◽  
William H. Oldendorf ◽  
Jim Mintz ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Images ◽  
Schizophrenic Patients

scholarly journals INDIRECT DECOMPRESSION BY LATERAL FUSION: ANALYSIS OF SAGITAL ALIGNMENT

2021 ◽  
Vol 20 (1) ◽  
pp. 50-54
Author(s):  
Thyago Guirelle Silva ◽  
Rodrigo Augusto do Amaral ◽  
Raphael Rezende Pratali ◽  
Luiz Pimenta
Keyword(s):  
Magnetic Resonance ◽  
Pelvic Incidence ◽  
Magnetic Resonance Images ◽  
Cross Sectional Area ◽  
Disc Height ◽  
Lower Limbs ◽  
Sectional Area ◽  
Cross Sectional ◽  
Indirect Decompression ◽  
The Mean

ABSTRACT Objective: To verify the effectiveness of indirect decompression after lateral access fusion in patients with high pelvic incidence. Methods: A retrospective, non-comparative, non-randomized analysis of 22 patients with high pelvic incidence who underwent lateral access fusion, 11 of whom were male and 11 female, with a mean age of 63 years (52-74), was conducted. Magnetic resonance exams were performed within one year after surgery. The cross-sectional area of the thecal sac, anterior and posterior disc heights, and bilateral foramen heights, measured pre- and postoperatively in axial and sagittal magnetic resonance images, were analyzed. The sagittal alignment parameters were measured using simple radiographs. The clinical results were evaluated using the ODI and VAS (back and lower limbs) questionnaires. Results: In all cases, the technique was performed successfully without neural complications. The mean cross-sectional area increased from 126.5 mm preoperatively to 174.3 mm postoperatively. The mean anterior disc height increased from 9.4 mm preoperatively to 12.8 mm postoperatively, while the posterior disc height increased from 6.3 mm preoperatively to 8.1 mm postoperatively. The mean height of the right foramen increased from 157.3 mm in the preoperative period to 171.2 mm in the postoperative period and that of the left foramen increased from 139.3 mm in the preoperative to 158.9 mm in the postoperative. Conclusions: This technique is capable of correcting misalignment in spinal deformity, achieving fusion and promoting the decompression of neural elements. Level of evidence III; Retrospective study.

scholarly journals The Proliferation of Dentate Gyrus Progenitors in the Ferret Hippocampus by Neonatal Exposure to Valproic Acid

2021 ◽  
Vol 15 ◽  
Author(s):  
Kazuhiko Sawada ◽  
Shiori Kamiya ◽  
Ichio Aoki
Keyword(s):  
Valproic Acid ◽  
Cerebral Cortex ◽  
Magnetic Resonance ◽  
Dentate Gyrus ◽  
Structural Changes ◽  
S100 Protein ◽  
Brain Regions ◽  
Autism Spectrum ◽  
Magnetic Resonance Images ◽  
Neonatal Exposure

Prenatal and neonatal exposure to valproic acid (VPA) is associated with human autism spectrum disorder (ASD) and can alter the development of several brain regions, such as the cerebral cortex, cerebellum, and amygdala. Neonatal VPA exposure induces ASD-like behavioral abnormalities in a gyrencephalic mammal, ferret, but it has not been evaluated in brain regions other than the cerebral cortex in this animal. This study aimed to facilitate a comprehensive understanding of brain abnormalities induced by developmental VPA exposure in ferrets. We examined gross structural changes in the hippocampus and tracked proliferative cells by 5-bromo-2-deoxyuridine (BrdU) labeling following VPA administration to ferret infants on postnatal days (PDs) 6 and 7 at 200 μg/g of body weight. Ex vivo short repetition time/time to echo magnetic resonance imaging (MRI) with high spatial resolution at 7-T was obtained from the fixed brain of PD 20 ferrets. The hippocampal volume estimated using MRI-based volumetry was not significantly different between the two groups of ferrets, and optical comparisons on coronal magnetic resonance images revealed no differences in gross structures of the hippocampus between VPA-treated and control ferrets. BrdU-labeled cells were observed throughout the hippocampus of both two groups at PD 20. BrdU-labeled cells were immunopositive for Sox2 (&gt;70%) and almost immunonegative for NeuN, S100 protein, and glial fibrillary acidic protein. BrdU-labeled Sox2-positive progenitors were abundant, particularly in the subgranular layer of the dentate gyrus (DG), and were denser in VPA-treated ferrets. When BrdU-labeled Sox2-positive progenitors were examined at 2 h after the second VPA administration on PD 7, their density in the granular/subgranular layer and hilus of the DG was significantly greater in VPA-treated ferrets compared to controls. The findings suggest that VPA exposure to ferret infants facilitates the proliferation of DG progenitors, supplying excessive progenitors for hippocampal adult neurogenesis to the subgranular layer.

The use of combined T2-weighted and FLAIR synthetic magnetic resonance images to improve white matter region contrast: a feasibility study

2019 ◽  
Vol 12 (1) ◽  
pp. 118-125 ◽  
Author(s):  
Yasuhiro Fujiwara ◽  
Yumi Inoue ◽  
Masayuki Kanamoto ◽  
Shota Ishida ◽  
Toshiki Adachi ◽  
...  
Keyword(s):  
White Matter ◽  
Magnetic Resonance ◽  
Feasibility Study ◽  
Magnetic Resonance Images ◽  
White Matter Region ◽  
Region Contrast

Partial capitate shortening for Kienböck’s disease

2014 ◽  
Vol 40 (9) ◽  
pp. 957-960 ◽  
Author(s):  
A. Citlak ◽  
U. Akgun ◽  
T. Bulut ◽  
M. Tahta ◽  
B. Dirim Mete ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Case Series ◽  
Magnetic Resonance Images ◽  
Stage Ii ◽  
Pinch Strength ◽  
Case Series Study ◽  
The Mean ◽  
Series Study ◽  
Carpal Height

The purpose of this study was to report our experience of partial capitate shortening in seven patients with a median 38 months follow-up. Staging was made by the Lichtman classification system and stage II and III-A patients were included in the study. The mean age was 34 years (range 22–52). Patients were assessed for pain, range of motion, grip and pinch strength, and satisfaction was recorded using a scale between 0 and 4. All these parameters showed improvement after surgery. The Lichtman stage, lunate height index and carpal height index were determined radiographically. Magnetic resonance images of the wrist were studied for lunate revascularization at the final follow-up and occurred in all patients. According to our study, partial capitate shortening seems an effective treatment for Lichtman stage II and III-A patients. Level IV case series study.

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