scholarly journals Automated Segmentation of Cerebellum Using Brain Mask and Partial Volume Estimation Map

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Dong-Kyun Lee ◽  
Uicheul Yoon ◽  
Kichang Kwak ◽  
Jong-Min Lee
Keyword(s):  
Brain Stem ◽  
Similarity Index ◽  
Volume Estimation ◽  
Morphological Operations ◽  
Cerebellar Tissue ◽  
Morphological Operator ◽  
Cerebellar Peduncle ◽  
The Individual ◽  
The Brain ◽  
Dice Similarity Index

While segmentation of the cerebellum is an indispensable step in many studies, its contrast is not clear because of the adjacent cerebrospinal fluid, meninges, and cerebra peduncle. Thus, various cerebellar segmentation methods, such as a deformable model or a template-based algorithm might exhibit incorrect segmentation of the venous sinuses and the cerebellar peduncle. In this study, we propose a fully automated procedure combining cerebellar tissue classification, a template-based approach, and morphological operations sequentially. The cerebellar region was defined approximately by removing the cerebral region from the brain mask. Then, the noncerebellar region was trimmed using a morphological operator and the brain-stem atlas was aligned to the individual brain to define the brain-stem area. The proposed method was validated with the well-known FreeSurfer and ITK-SNAP packages using the dice similarity index and recall and precision scores. As a result, the proposed method was significantly better than the other methods for the dice similarity index (0.93, FreeSurfer: 0.92, ITK-SNAP: 0.87) and precision (0.95, FreeSurfer: 0.90, ITK-SNAP: 0.93). Therefore, it could be said that the proposed method yielded a robust and accurate segmentation result. Moreover, additional postprocessing with the brain-stem atlas could improve its result.

scholarly journals Pathophysiological changes in the cerebellum and brain stem in a rabbit model after superior petrosal vein sacrifice

2018 ◽  
Vol 38 (6) ◽  
Author(s):  
Lei Cheng ◽  
Pin Guo ◽  
Yi-wei Liao ◽  
Hong-liang Zhang ◽  
Huan-ting Li ◽  
...  
Keyword(s):  
Brain Stem ◽  
Rabbit Model ◽  
Control Group ◽  
Stem Tissue ◽  
Nissl Staining ◽  
Petrosal Vein ◽  
Time Period ◽  
Cerebellar Tissue ◽  
Superior Petrosal Vein ◽  
The Brain

In certain surgical procedures, sacrificing the superior petrosal vein (SPV) is required. Previous studies have reported transient cerebellar edema, venous infarction, or hemorrhage that might occur after sectioning of the SPV. The present study investigated the pathophysiological changes in cerebellum and brain stem after SPV sacrifice. Rabbits were divided into the operation group where the SPV was sacrificed and the control group where the SPV remained intact. Each group was further subdivided into 4, 8, 12, 24, 48, and 72 h groups which represented the time period from sacrificing of the SPV to killing of the rabbits. The water content (WC), Na+ content, K+ content, and pathophysiological changes in cerebellum and brain stem tissue were measured. In comparison with the control, the WC and Na+ content of cerebellar tissue were increased in the 4, 8, 12, and 24 h operation subgroups (P<0.05), but only increased in the 4-h subgroup of the brain stem tissue (P<0.05). The K+ content of the cerebellar tissue decreased in the 4, 8, 12, and 24 h operation subgroups (P<0.05) but only decreased in the 4-h subgroup of brain stem tissue (P<0.05). Nissl staining and TEM demonstrated that cerebellar edema occurred in the 4, 8, 12, and 24 h operation subgroups but not in the 48- and 72-h subgroups. Brain stem edema occurred in the 4-h operation subgroup. In summary, cerebellum and brain stem edema can be observed at different time points after sacrificing of the SPV in the rabbit model.

scholarly journals Stereological Evaluation of the Brains in Patients with Parkinson’s disease Compared to Controls

2017 ◽  
Vol 25 (3) ◽  
pp. 265-274 ◽  
Author(s):  
Zahra Heidari ◽  
Ali Moghtaderi ◽  
Hamidreza Mahmoudzadeh-Sagheb ◽  
Enam Alhagh Charkhat Gorgich
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Brain Stem ◽  
Volume Density ◽  
Control Group ◽  
Middle Cerebellar Peduncle ◽  
Significance Level ◽  
Significant Difference ◽  
Cerebellar Peduncle ◽  
The Brain

Abstract Parkinson’s disease (PD) is a chronic and progressive neurological disorder. A tetrad of bradykinesia, rigidity, tremor and postural instability are the core features of the disease. The aim of this study was to evaluate stereological changes in the brain of patients with PD and compare them with that of healthy controls. This case-control study was conducted on 29 patients with PD and 12 controls (C) in Zahedan, Iran. All subjects enrolled into the study through the convenience sampling method. MRI images of the brains of two groups in frontal and sagittal axis with consecutive 5mm distance slices were captured. Parameters including total volume (V) and volume density (Vv) of different parts of the brain were estimated based on Cavalries’ point counting stereological method. To analyze the data, descriptive statistics, Mann-Whitney U-Test applied for comparing the PD and C groups were used. Significance level was set at p<0.05. Our study showed that the volume of the brain and total volume and volume density (Vv) of cerebral hemispheres, cerebellum, ventricles, hippocampus, pons, mid brain and superior cerebellar peduncles in the PD group did not indicate significant difference from the control group. Total volume of brain stem in PD group wasn’t significantly different from the control group. The volume density of brain stem (p= 0.012) and total volume and volume density of middle cerebellar peduncle (p< 0.0001) in PD group were significantly larger than the control group. This study shows that PD stereological parameters related to volume and volume density of middle cerebellar peduncle and volume density of brain stem were significantly larger in patients compared to the controls. Therefore, stereological parameters can be used for early diagnosis and probably for follow-up in patients with PD.

Projections of the individual vestibular end-organs in the brain stem of the squirrel monkey

1995 ◽  
Vol 87 (1-2) ◽  
pp. 141-155 ◽  
Author(s):  
Yasushi Naito ◽  
Anita Newman ◽  
Won Sang Lee ◽  
Karl Beykirch ◽  
Vicente Honrubia
Keyword(s):  
Brain Stem ◽  
Squirrel Monkey ◽  
The Individual ◽  
The Brain

Permeability of the microcirculation in area postrema of rat

1988 ◽  
Vol 46 ◽  
pp. 348-349
Author(s):  
Shams M. Ghoneim ◽  
Frank M. Faraci ◽  
Gary L. Baumbach
Keyword(s):  
Brain Stem ◽  
Area Postrema ◽  
Upper Body ◽  
Sprague Dawley ◽  
Sodium Cacodylate ◽  
Acute Hypertension ◽  
Sprague Dawley Rats ◽  
Ultrastructural Characteristics ◽  
The Brain ◽  
Adjacent Brain

The area postrema is a circumventricular organ in the brain stem and is one of the regions in the brain that lacks a fully functional blood-brain barrier. Recently, we found that disruption of the microcirculation during acute hypertension is greater in area postrema than in the adjacent brain stem. In contrast, hyperosmolar disruption of the microcirculation is greater in brain stem. The objective of this study was to compare ultrastructural characteristics of the microcirculation in area postrema and adjacent brain stem.We studied 5 Sprague-Dawley rats. Horseradish peroxidase was injected intravenously and allowed to circulate for 1, 5 or 15 minutes. Following perfusion of the upper body with 2.25% glutaraldehyde in 0.1 M sodium cacodylate, the brain stem was removed, embedded in agar, and chopped into 50-70 μm sections with a TC-Sorvall tissue chopper. Sections of brain stem were incubated for 1 hour in a solution of 3,3' diaminobenzidine tetrahydrochloride (0.05%) in 0.05M Tris buffer with 1% H2O2.

Fit Vs Faint: Assessing Work Causation in “Idiopathic Fall” Cases

2014 ◽  
Vol 19 (5) ◽  
pp. 3-12
Author(s):  
Lorne Direnfeld ◽  
David B. Torrey ◽  
Jim Black ◽  
LuAnn Haley ◽  
Christopher R. Brigham
Keyword(s):  
Blood Flow ◽  
Electrical Activity ◽  
Loss Of Consciousness ◽  
Brain Electrical Activity ◽  
Medical Terminology ◽  
Scientific Analysis ◽  
Medical Causation ◽  
The Individual ◽  
The Brain ◽  
Current Science

Abstract When an individual falls due to a nonwork-related episode of dizziness, hits their head and sustains injury, do workers’ compensation laws consider such injuries to be compensable? Bearing in mind that each state makes its own laws, the answer depends on what caused the loss of consciousness, and the second asks specifically what happened in the fall that caused the injury? The first question speaks to medical causation, which applies scientific analysis to determine the cause of the problem. The second question addresses legal causation: Under what factual circumstances are injuries of this type potentially covered under the law? Much nuance attends this analysis. The authors discuss idiopathic falls, which in this context means “unique to the individual” as opposed to “of unknown cause,” which is the familiar medical terminology. The article presents three detailed case studies that describe falls that had their genesis in episodes of loss of consciousness, followed by analyses by lawyer or judge authors who address the issue of compensability, including three scenarios from Arizona, California, and Pennsylvania. A medical (scientific) analysis must be thorough and must determine the facts regarding the fall and what occurred: Was the fall due to a fit (eg, a seizure with loss of consciousness attributable to anormal brain electrical activity) or a faint (eg, loss of consciousness attributable to a decrease in blood flow to the brain? The evaluator should be able to fully explain the basis for the conclusions, including references to current science.

Surgical Approaches to the Brain Stem

1993 ◽  
Vol 4 (3) ◽  
pp. 457-468 ◽  
Author(s):  
Dennis Y. Wen ◽  
Roberto C. Heros
Keyword(s):  
Brain Stem ◽  
Surgical Approaches ◽  
The Brain

ADRENERGIC INPUTS TO THE AMYGDALA AND THE CONTROL OF GONADOTROPHIN RELEASE

1979 ◽  
Vol 90 (3) ◽  
pp. 385-393 ◽  
Author(s):  
José Borrell ◽  
Flavio Piva ◽  
Luciano Martini
Keyword(s):  
Brain Stem ◽  
Dopamine Receptor ◽  
Serum Levels ◽  
Female Rats ◽  
Receptor Blocker ◽  
Dopaminergic Drug ◽  
Gonadotrophin Secretion ◽  
Biphasic Effect ◽  
Adrenergic Blocker ◽  
The Brain

ABSTRACT Drugs able to mimic or to antagonize the action of catecholamines have been implanted bilaterally into the basomedial region of the amygdala of adult castrated female rats. The animals were killed at different intervals after the implantation of the different drugs, and serum levels of LH and FSH were measured by radioimmunoassay. The results have shown that the intra-amygdalar implantation of the alpha-adrenergic blocker phenoxybenzamine induces a significant increase of the release both of LH and FSH. The implantation of the beta-adrenergic blocker propranolol brings about a rise of LH only. The dopamine receptor blocker pimozide stimulates the release of LH and exerts a biphasic effect (stimulation followed by inhibition) of FSH secretion. The alpha-receptor stimulant clonidine and the dopaminergic drug 2-Br-alpha-ergocryptine were without significant effects. From these observations it is suggested that the adrenergic signals reaching the basomedial area of the amygdala (possibly from the brain stem) may be involved in the modulation of gonadotrophin secretion.

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