scholarly journals Estimating Cortical Surface Motion Using Stereopsis for Brain Deformation Models

2003 ◽  
pp. 794-801 ◽  
Author(s):  
Hai Sun ◽  
Hany Farid ◽  
Kyle Rick ◽  
Alex Hartov ◽  
David W. Roberts ◽  
...  
Keyword(s):  
Cortical Surface ◽  
Surface Motion ◽  
Brain Deformation ◽  
Deformation Models

scholarly journals Intraoperative image updating for brain shift following dural opening

2016 ◽  
Vol 126 (6) ◽  
pp. 1924-1933 ◽  
Author(s):  
Xiaoyao Fan ◽  
David W. Roberts ◽  
Timothy J. Schaewe ◽  
Songbai Ji ◽  
Leslie H. Holton ◽  
...  
Keyword(s):  
Biomechanical Model ◽  
Magnetic Resonance Images ◽  
Computational Time ◽  
Average Error ◽  
Cortical Surface ◽  
Brain Shift ◽  
Surgical Workflow ◽  
Brain Deformation ◽  
Time Required ◽  
Dural Opening

OBJECTIVEPreoperative magnetic resonance images (pMR) are typically coregistered to provide intraoperative navigation, the accuracy of which can be significantly compromised by brain deformation. In this study, the authors generated updated MR images (uMR) in the operating room (OR) to compensate for brain shift due to dural opening, and evaluated the accuracy and computational efficiency of the process.METHODSIn 20 open cranial neurosurgical cases, a pair of intraoperative stereovision (iSV) images was acquired after dural opening to reconstruct a 3D profile of the exposed cortical surface. The iSV surface was registered with pMR to detect cortical displacements that were assimilated by a biomechanical model to estimate whole-brain nonrigid deformation and produce uMR in the OR. The uMR views were displayed on a commercial navigation system and compared side by side with the corresponding coregistered pMR. A tracked stylus was used to acquire coordinate locations of features on the cortical surface that served as independent positions for calculating target registration errors (TREs) for the coregistered uMR and pMR image volumes.RESULTSThe uMR views were visually more accurate and well aligned with the iSV surface in terms of both geometry and texture compared with pMR where misalignment was evident. The average misfit between model estimates and measured displacements was 1.80 ± 0.35 mm, compared with the average initial misfit of 7.10 ± 2.78 mm between iSV and pMR, and the average TRE was 1.60 ± 0.43 mm across the 20 patients in the uMR image volume, compared with 7.31 ± 2.82 mm on average in the pMR cases. The iSV also proved to be accurate with an average error of 1.20 ± 0.37 mm. The overall computational time required to generate the uMR views was 7–8 minutes.CONCLUSIONSThis study compensated for brain deformation caused by intraoperative dural opening using computational model–based assimilation of iSV cortical surface displacements. The uMR proved to be more accurate in terms of model-data misfit and TRE in the 20 patient cases evaluated relative to pMR. The computational time was acceptable (7–8 minutes) and the process caused minimal interruption of surgical workflow.

Cortical Surface Motion Estimation for Brain Shift Prediction

2010 ◽  
pp. 53-62 ◽  
Author(s):  
Grand Roman Joldes ◽  
Adam Wittek ◽  
Karol Miller
Keyword(s):  
Motion Estimation ◽  
Cortical Surface ◽  
Brain Shift ◽  
Surface Motion

scholarly journals A Simple Method to Avoid Brain Shift during Neuronavigation: Technical Note

2020 ◽  
Author(s):  
Jair Leopoldo Raso
Keyword(s):  
Dura Mater ◽  
Brain Area ◽  
Conventional Technique ◽  
Technical Note ◽  
Cortical Surface ◽  
Brain Shift ◽  
Simple Method ◽  
Cortex Area ◽  
Neuronavigation System ◽  
The Brain

Abstract Introduction The precise identification of anatomical structures and lesions in the brain is the main objective of neuronavigation systems. Brain shift, displacement of the brain after opening the cisterns and draining cerebrospinal fluid, is one of the limitations of such systems. Objective To describe a simple method to avoid brain shift in craniotomies for subcortical lesions. Method We used the surgical technique hereby described in five patients with subcortical neoplasms. We performed the neuronavigation-guided craniotomies with the conventional technique. After opening the dura and exposing the cortical surface, we placed two or three arachnoid anchoring sutures to the dura mater, close to the edges of the exposed cortical surface. We placed these anchoring sutures under microscopy, using a 6–0 mononylon wire. With this technique, the cortex surface was kept close to the dura mater, minimizing its displacement during the approach to the subcortical lesion. In these five cases we operated, the cortical surface remained close to the dura, anchored by the arachnoid sutures. All the lesions were located with a good correlation between the handpiece tip inserted in the desired brain area and the display on the navigation system. Conclusion Arachnoid anchoring sutures to the dura mater on the edges of the cortex area exposed by craniotomy constitute a simple method to minimize brain displacement (brain-shift) in craniotomies for subcortical injuries, optimizing the use of the neuronavigation system.

scholarly journals Constructing Adaptive Deformation Models for Estimating DEM Error in SBAS-InSAR Based on Hypothesis Testing

2021 ◽  
Vol 13 (10) ◽  
pp. 2006
Author(s):  
Jun Hu ◽  
Qiaoqiao Ge ◽  
Jihong Liu ◽  
Wenyan Yang ◽  
Zhigui Du ◽  
...  
Keyword(s):  
Time Series ◽  
Hypothesis Testing ◽  
Surface Deformation ◽  
A Priori ◽  
Least Square ◽  
Deformation Model ◽  
Phase Time ◽  
Testing Theory ◽  
Sbas Insar ◽  
Deformation Models

The Interferometric Synthetic Aperture Radar (InSAR) technique has been widely used to obtain the ground surface deformation of geohazards (e.g., mining subsidence and landslides). As one of the inherent errors in the interferometric phase, the digital elevation model (DEM) error is usually estimated with the help of an a priori deformation model. However, it is difficult to determine an a priori deformation model that can fit the deformation time series well, leading to possible bias in the estimation of DEM error and the deformation time series. In this paper, we propose a method that can construct an adaptive deformation model, based on a set of predefined functions and the hypothesis testing theory in the framework of the small baseline subset InSAR (SBAS-InSAR) method. Since it is difficult to fit the deformation time series over a long time span by using only one function, the phase time series is first divided into several groups with overlapping regions. In each group, the hypothesis testing theory is employed to adaptively select the optimal deformation model from the predefined functions. The parameters of adaptive deformation models and the DEM error can be modeled with the phase time series and solved by a least square method. Simulations and real data experiments in the Pingchuan mining area, Gaunsu Province, China, demonstrate that, compared to the state-of-the-art deformation modeling strategy (e.g., the linear deformation model and the function group deformation model), the proposed method can significantly improve the accuracy of DEM error estimation and can benefit the estimation of deformation time series.

scholarly journals Analysis of loading curve characteristics on the production of brain deformation metrics

2012 ◽  
Vol 226 (3-4) ◽  
pp. 200-207 ◽  
Author(s):  
Andrew Post ◽  
Evan S Walsh ◽  
T Blaine Hoshizaki ◽  
Michael D Gilchrist
Keyword(s):  
Brain Deformation

scholarly journals Lesion with blue bone-a case report

2018 ◽  
Vol 8 (1) ◽  
pp. 1323-1325
Author(s):  
Laila Mohamed Ilias ◽  
Babitha Alingal Mohammed ◽  
Roshini PS ◽  
Anupama Ponniah ◽  
Poornima Vijayan
Keyword(s):  
Histopathological Examination ◽  
Fibrous Tissue ◽  
Bone Lesion ◽  
Metacarpal Bone ◽  
Cortical Surface ◽  
Bizarre Parosteal Osteochondromatous Proliferation ◽  
X Ray ◽  
Spindle Cells ◽  
Small Bones ◽  
Hands And Feet

Bizzare parosteal osteochondromatous proliferation, or Nora‘s lesion is a unique bone lesion that most often arises in the small bones of hands and feet.  It is characterised by proliferation of chondroid, bony and fibrous tissue, and is occasionally misdiagnosed as a malignant process.  Our case was a 31 yr old lady, who presented with a painless swelling near the 5th metacarpal bone of right hand.  X-ray showed well marginated mineralised mass arising from the cortical surface of the metacarpal bone.  Histopathological examination revealed bizarre parosteal osteochondromatous proliferation composed of varying amounts of cartilage, bone and spindle cells. Cartilage was hypercellular and chondrocytes were enlarged. Ossification was irregular and had a peculiar blue tinctorial quality. 

scholarly journals Distributed Scatterer InSAR Reveals Surface Motion of the Ancient Chaoshan Residence Cluster in the Lianjiang Plain, China

2019 ◽  
Vol 11 (2) ◽  
pp. 166 ◽  
Author(s):  
Yuzhou Liu ◽  
Peifeng Ma ◽  
Hui Lin ◽  
Weixi Wang ◽  
Guoqiang Shi
Keyword(s):  
Time Series ◽  
Deformation Rate ◽  
First Generation ◽  
Groundwater Resources ◽  
Potential Threat ◽  
Groundwater Exploitation ◽  
Surface Motion ◽  
Elastic Rebound ◽  
Surface Patterns ◽  
Change Dynamic

The Lianjiang Plain in China and ancient villages distributed within the plain are under the potential threat of surface motion change, but no effective monitoring strategy currently exists. Distributed Scatterer InSAR (DSInSAR) provides a new high-resolution method for the precise detection of surface motion change. In contrast to the first-generation of time-series InSAR methodology, the distributed scatterer-based method focuses both on pointwise targets with high phase stability and distributed targets with moderate coherence, the latter of which is more suitable for the comprehensive environment of the Lianjiang Plain. In this paper, we present the first study of surface motion change detection in the Lianjiang Plain, China. Two data stacks, including 54 and 29 images from Sentinel-1A adjacent orbits, are used to retrieve time-series surface motion changes for the Lianjiang Plain from 2015 to 2018. The consistency of measurement has been cross-validated between adjacent orbit results with a statistically significant determination coefficient of 0.92. The temporal evolution of representative measuring points indicates three subzones with varied surface patterns: Eastern Puning (Zone A) in a slight elastic rebound phase with a moderate deformation rate (0–40 mm/yr), Chaonan (Zone B) in a substantial subsidence phase with a strong deformation rate (−140–0 mm/yr), and Chaoyang (Zone C) in a homogeneous and stable situation (−10–10 mm/yr). The spatial distribution of these zones suggests a combined change dynamic and a strong concordance of factors impacting surface motion change. Human activities, especially groundwater exploitation, dominate the subsidence pattern, and natural conditions act as a supplementary inducement by providing a hazard-prone environment. The qualitative and quantitative analysis of spatial and temporal details in this study provides a basis for systematic surface motion monitoring, cultural heritage protection and groundwater resources management.

Motion periodicity and bifurcation of a wave excited hopping ball

2019 ◽  
Vol 475 (2228) ◽  
pp. 20190137
Author(s):  
Gaurang Ruhela ◽  
Anirvan DasGupta
Keyword(s):  
Wave Amplitude ◽  
Harmonic Wave ◽  
Inelastic Collisions ◽  
Loss Of Stability ◽  
Elastic Surface ◽  
Minimum Frequency ◽  
Surface Motion ◽  
Return Map ◽  
Ball Problem ◽  
Subsequent Loss

We consider the problem of a hopping ball excited by a travelling harmonic wave on an elastic surface. The ball, considered as a particle, is assumed to interact with the surface through inelastic collisions. The surface motion due to the wave induces a horizontal drift in the ball. The problem is treated analytically under certain approximations. The phase space of the hopping motion is captured by constructing a phase-velocity return map. The fixed points of the return map and its compositions represent periodic hopping solutions. The linear stability of the obtained periodic solution is studied in detail. The minimum frequency for the onset of periodic hops, and the subsequent loss of stability at the bifurcation frequency, have been determined analytically. Interestingly, for small values of wave amplitude, the analytical solutions reveal striking similarities with the results of the classical bouncing ball problem.

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