scholarly journals Virtual reality improves the accuracy of simulated preoperative planning in temporal bones: a feasibility and validation study

2020 ◽  
Author(s):  
Tomi Timonen ◽  
Matti Iso-Mustajärvi ◽  
Pia Linder ◽  
Antti Lehtimäki ◽  
Heikki Löppönen ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Measurement Errors ◽  
Surgical Planning ◽  
Image Data ◽  
Distance Measurements ◽  
Cross Sectional ◽  
Fresh Frozen ◽  
Picture Archiving And Communication ◽  
Mean Differences ◽  
Temporal Bones

Abstract Purpose Consumer-grade virtual reality (VR) has recently enabled various medical applications, but more evidence supporting their validity is needed. We investigated the accuracy of simulated surgical planning in a VR environment (VR) with temporal bones and compared it to conventional cross-sectional image viewing in picture archiving and communication system (PACS) interface. Methods Five experienced otologic surgeons measured significant anatomic structures and fiducials on five fresh-frozen cadaveric temporal bones in VR and cross-sectional viewing. Primary image data were acquired by computed tomography. In total, 275 anatomical landmark measurements and 250 measurements of the distance between fiducials were obtained with both methods. Distance measurements between the fiducials were confirmed by physical measurement obtained by Vernier caliper. The experts evaluated the subjective validity of both methods on a 5-point Likert scale qualitative survey. Results A strong correlation based on intraclass coefficient was found between the methods on both the anatomical (r > 0.900) and fiducial measurements (r > 0.916). Two-tailed paired t-test and Bland–Altman plots demonstrated high equivalences between the VR and cross-sectional viewing with mean differences of 1.9% (p = 0.396) and 0.472 mm (p = 0.065) for anatomical and fiducial measurements, respectively. Gross measurement errors due to the misidentification of fiducials occurred more frequently in the cross-sectional viewing. The mean face and content validity rating for VR were significantly better compared to cross-sectional viewing (total mean score 4.11 vs 3.39, p < 0.001). Conclusion Our study supports good accuracy and reliability of VR environment for simulated surgical planning in temporal bones compared to conventional cross-sectional visualization.

scholarly journals The effect of virtual reality on temporal bone anatomy evaluation and performance

2021 ◽  
Author(s):  
Tomi Timonen ◽  
Aarno Dietz ◽  
Pia Linder ◽  
Antti Lehtimäki ◽  
Heikki Löppönen ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Temporal Bone ◽  
User Experience ◽  
Anatomical Landmarks ◽  
Expert Group ◽  
Cross Sectional ◽  
Performance Time ◽  
Computed Tomography Images ◽  
Temporal Bone Anatomy ◽  
Temporal Bones

Abstract Purpose There is only limited data on the application of virtual reality (VR) for the evaluation of temporal bone anatomy. The aim of the present study was to compare the VR environment to traditional cross-sectional viewing of computed tomography images in a simulated preoperative planning setting in novice and expert surgeons. Methods A novice (n = 5) and an expert group (n = 5), based on their otosurgery experience, were created. The participants were asked to identify 24 anatomical landmarks, perform 11 distance measurements between surgically relevant anatomical structures and 10 fiducial markers on five cadaver temporal bones in both VR environment and cross-sectional viewings in PACS interface. The data on performance time and user-experience (i.e., subjective validation) were collected. Results The novice group made significantly more errors (p < 0.001) and with significantly longer performance time (p = 0.001) in cross-sectional viewing than the expert group. In the VR environment, there was no significant differences (errors and time) between the groups. The performance of novices improved faster in the VR. The novices showed significantly faster task performance (p = 0.003) and a trend towards fewer errors (p = 0.054) in VR compared to cross-sectional viewing. No such difference between the methods were observed in the expert group. The mean overall scores of user-experience were significantly higher for VR than cross-sectional viewing in both groups (p < 0.001). Conclusion In the VR environment, novices performed the anatomical evaluation of temporal bone faster and with fewer errors than in the traditional cross-sectional viewing, which supports its efficiency for the evaluation of complex anatomy.

Automated Diagonal Slice and View Solution for 3D Device Structure Analysis

2018 ◽  
Author(s):  
Sang Hoon Lee ◽  
Jeff Blackwood ◽  
Stacey Stone ◽  
Michael Schmidt ◽  
Mark Williamson ◽  
...  
Keyword(s):  
Cross Section ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Image Data ◽  
Planar Surface ◽  
Device Structure ◽  
Cross Sectional ◽  
Device Structures ◽  
The Cross ◽  
Planar Analysis

Abstract The cross-sectional and planar analysis of current generation 3D device structures can be analyzed using a single Focused Ion Beam (FIB) mill. This is achieved using a diagonal milling technique that exposes a multilayer planar surface as well as the cross-section. this provides image data allowing for an efficient method to monitor the fabrication process and find device design errors. This process saves tremendous sample-to-data time, decreasing it from days to hours while still providing precise defect and structure data.

scholarly journals Minimally Invasive Mini-orbitozygomatic Approach for Clipping an Anterior Communicating Artery Aneurysm: Virtual Reality Surgical Planning

2020 ◽  
Author(s):  
Nicolás González Romo ◽  
Franco Ravera Zunino
Keyword(s):  
Virtual Reality ◽  
Minimally Invasive ◽  
Surgical Planning ◽  
Artery Aneurysm ◽  
Patient Specific ◽  
Anterior Communicating Artery ◽  
Imaging Data ◽  
Advantages And Disadvantages ◽  
Orbitozygomatic Approach ◽  
Skull Base Anatomy

AbstractVirtual reality (VR) has increasingly been implemented in neurosurgical practice. A patient with an unruptured anterior communicating artery (AcoA) aneurysm was referred to our institution. Imaging data from computed tomography angiography (CTA) was used to create a patient specific 3D model of vascular and skull base anatomy, and then processed to a VR compatible environment. Minimally invasive approaches (mini-pterional, supraorbital and mini-orbitozygomatic) were simulated and assessed for adequate vascular exposure in VR. Using an eyebrow approach, a mini-orbitozygomatic approach was performed, with clip exclusion of the aneurysm from the circulation. The step-by-step process of VR planning is outlined, and the advantages and disadvantages for the neurosurgeon of this technology are reviewed.

scholarly journals Deep learning-based estimation of Flory–Huggins parameter of A–B block copolymers from cross-sectional images of phase-separated structures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Katsumi Hagita ◽  
Takeshi Aoyagi ◽  
Yuto Abe ◽  
Shinya Genda ◽  
Takashi Honda
Keyword(s):  
Deep Learning ◽  
Diblock Copolymers ◽  
Three Dimensional ◽  
Image Data ◽  
Real Space ◽  
Cross Sectional ◽  
Regression Problem ◽  
Self Consistent Field ◽  
Experimental Image ◽  
Chain Lengths

AbstractIn this study, deep learning (DL)-based estimation of the Flory–Huggins χ parameter of A-B diblock copolymers from two-dimensional cross-sectional images of three-dimensional (3D) phase-separated structures were investigated. 3D structures with random networks of phase-separated domains were generated from real-space self-consistent field simulations in the 25–40 χN range for chain lengths (N) of 20 and 40. To confirm that the prepared data can be discriminated using DL, image classification was performed using the VGG-16 network. We comprehensively investigated the performances of the learned networks in the regression problem. The generalization ability was evaluated from independent images with the unlearned χN. We found that, except for large χN values, the standard deviation values were approximately 0.1 and 0.5 for A-component fractions of 0.2 and 0.35, respectively. The images for larger χN values were more difficult to distinguish. In addition, the learning performances for the 4-class problem were comparable to those for the 8-class problem, except when the χN values were large. This information is useful for the analysis of real experimental image data, where the variation of samples is limited.

scholarly journals Clinical rearfoot and knee static alignment measurements are not associated with patellofemoral pain syndrome

2012 ◽  
Vol 19 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Sandra Aliberti ◽  
Mariana Souza Xavier Costa ◽  
Sílvia Maria Amado João ◽  
Anice de Campos Pássaro ◽  
Antonio Carlos Arnone ◽  
...  
Keyword(s):  
Odds Ratio ◽  
Pain Syndrome ◽  
Patellofemoral Pain Syndrome ◽  
Patellofemoral Pain ◽  
Cross Sectional ◽  
Q Angle ◽  
Limited Applicability ◽  
Mean Differences ◽  
Continuous Measures ◽  
Control Study

The aim of the present study was to investigate the association between the patellofemoral pain syndrome and the clinical static measurements: the rearfoot and the Q angles. The design was a cross-sectional, observational, case-control study. We evaluated 77 adults (both genders), 30 participants with patellofemoral pain syndrome, and 47 controls. We measured the rearfoot and Q angles by photogrammetry. Independent t-tests were used to compare outcome continuous measures between groups. Outcome continuous data were also transformed into categorical clinical classifications, in order to verify their statistical association with the dysfunction, and χ2 tests for multiple responses were used. There were no differences between groups for rearfoot angle [mean differences: 0.2º (95%CI -1.4-1.8)] and Q angle [mean differences: -0.3º (95%CI -3.0-2.4). No associations were found between increased rearfoot valgus [Odds Ratio: 1.29 (95%CI 0.51-3.25)], as well as increased Q angle [Odds Ratio: 0.77 (95%CI 0.31-1.93)] and the patellofemoral pain syndrome occurrence. Although widely used in clinical practice and theoretically thought, it cannot be affirmed that increased rearfoot valgus and increased Q angle, when statically measured in relaxed stance, are associated with patellofemoral pain syndrome (PFPS). These measures may have limited applicability in screening of the PFPS development.

scholarly journals Geospatial simulations of airborne ice-penetrating radar surveying reveal elevation under-measurement bias for ice-sheet bed topography

2020 ◽  
Vol 61 (81) ◽  
pp. 46-57 ◽  
Author(s):  
Oliver T. Bartlett ◽  
Steven J. Palmer ◽  
Dustin M. Schroeder ◽  
Emma J. MacKie ◽  
Timothy T. Barrows ◽  
...  
Keyword(s):  
Measurement Errors ◽  
Survey Design ◽  
Ice Sheet ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Ice Dynamics ◽  
Outlet Glacier ◽  
Bed Topography ◽  
Novel Approach

AbstractAirborne radio-echo sounding (RES) surveys are widely used to measure ice-sheet bed topography. Measuring bed topography as accurately and widely as possible is of critical importance to modelling ice dynamics and hence to constraining better future ice response to climate change. Measurement accuracy of RES surveys is influenced both by the geometry of bed topography and the survey design. Here we develop a novel approach for simulating RES surveys over glaciated terrain, to quantify the sensitivity of derived bed elevation to topographic geometry. Furthermore, we investigate how measurement errors influence the quantification of glacial valley geometry. We find a negative bias across RES measurements, where off-nadir return measurement error is typically −1.8 ± 11.6 m. Topographic highlands are under-measured an order of magnitude more than lowlands. Consequently, valley depth and cross-sectional area are largely under-estimated. While overall estimates of ice thickness are likely too high, we find large glacier valley cross-sectional area to be under-estimated by −2.8 ± 18.1%. Therefore, estimates of ice flux through large outlet glaciers are likely too low when this effect is not taken into account. Additionally, bed mismeasurements potentially impact our appreciation of outlet-glacier stability.

scholarly journals 3D Virtual Reality Imaging of Major Aortopulmonary Collateral Arteries: A Novel Diagnostic Modality

2021 ◽  
pp. 215013512110450
Author(s):  
Pieter C. van de Woestijne ◽  
Wouter Bakhuis ◽  
Amir H. Sadeghi ◽  
Jette J. Peek ◽  
Yannick J.H.J. Taverne ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Surgical Planning ◽  
New Technology ◽  
Pulmonary Atresia ◽  
Diagnostic Modality ◽  
Topographic Anatomy ◽  
Major Aortopulmonary Collateral Arteries ◽  
Collateral Arteries ◽  
Clinical Benefits ◽  
Aortopulmonary Collateral

Background Major aortopulmonary collateral arteries (MAPCAs), as seen in patients with pulmonary atresia, are arteries that supply blood from the aorta to the lungs and often require surgical intervention. To achieve complete repair in the least number of interventions, optimal imaging of the pulmonary arterial anatomy and MAPCAs is critical. 3D virtual reality (3D-VR) is a promising and upcoming new technology that could potentially ameliorate current imaging shortcomings. Methods A retrospective, proof-of-concept study was performed of all operated patients with pulmonary atresia and MAPCAs at our center between 2010 and 2020 with a preoperative computed tomography (CT) scan. CT images were reviewed by two congenital cardiac surgeons in 3D-VR to determine additional value of VR for MAPCA imaging compared to conventional CT and for preoperative planning of MAPCA repair. Results 3D-VR visualizations were reconstructed from CT scans of seven newborns where the enhanced topographic anatomy resulted in improved visualization of MAPCA. In addition, surgical planning was improved since new observations or different preoperative plans were apparent in 4 out of 7 cases. After the initial setup, VR software and hardware was reported to be easy and intuitive to use. Conclusions This study showed technical feasibility of 3D-VR reconstruction of children with immersive visualization of topographic anatomy in an easy-to-use format leading to an improved surgical planning of MAPCA surgery. Future prospective studies are required to investigate the clinical benefits in larger populations.

scholarly journals Neuronavigation as a Tool for Pre-Surgical Planning in Refractory Epilepsy Surgery

2019 ◽  
Vol 5 (2) ◽  
pp. 01-10
Author(s):  
Carlos Valencia Calderón
Keyword(s):  
Epilepsy Surgery ◽  
Surgical Planning ◽  
Refractory Epilepsy ◽  
Surgical Experience ◽  
Surgical Time ◽  
Cross Sectional ◽  
Guided Surgery ◽  
Image Guided ◽  
Eloquent Areas ◽  
High Incidence

Summary Epilepsy is one of the most frequent chronic neurological pathologies, with high incidence and prevalence worldwide. A third of these patients are resistant to treatment, which is known as refractory epilepsy. Most of these patients suffer epilepsy secondary to epileptogenic lesions, where the surgery is the only treatment that could cure epilepsy. The goal of epilepsy surgery is to remove the epileptogenic area with preservation of eloquent areas, and here the surgical experience, the neuroimaging technology and the availability of image-guided surgery systems known as a neuronavigator plays a key role. Objectives: To demonstrate the usefulness of neuronavigation in pre-surgical planning and in the surgery of refractory epilepsy. Method: A cross-sectional and analytical descriptive study was conducted based on 47 surgeries performed (12 resective, 32 palliative and 3 diagnostic) in patients with refractory epilepsy and mean age of 9.93 years (SD 4.1). In 27 patients (57.44%) the neuronavigator was used. In the group of patients operated with neuronavigation, the surgical time decreased by 47.17 minutes (p = 0.022), the amount of bleeding by 111.41 milliliters (p = 0.011) and the days of hospitalization by 6.68 days (p = 0.005), compared with the group operated without neuronavigation. Complications in the neuronavigation group were 29.63% compared to 65% in the group operated without neuronavigation (p = 0.034). Conclusions: In our series, the use of the neuronavigator in the planning and development of the surgery had a significant impact by reducing the amount of bleeding lost, the surgical time, the days of hospitalization, and the post-surgical complications.

scholarly journals MRI Image Reconstruction using Compressive Sensing

2019 ◽  
Vol 8 (2) ◽  
pp. 5256-5260
Keyword(s):  
Compressive Sensing ◽  
Communication Systems ◽  
Optimization Algorithms ◽  
Image Data ◽  
Acquisition Time ◽  
Huge Amount ◽  
Scan Time ◽  
Small Set ◽  
Picture Archiving And Communication ◽  
Made In

A large number of diagnostic images which also include the MRIs are generated by the imaging departments of the hospitals for medical and legal reasons. This results in the creation of a huge amount of data in the form of images which are required to be stored for a long period. The primary challenge for the picture archiving and communication systems (PACS) allowing to store the image data and the display and reconstruction of the image for recalling at various sites. Image compression and reconstruction are necessary to cope up with these tasks. Significant efforts have been made in the recent towards the application of compressive sensing techniques for acquiring the data in MRI process. The primary aim of the theory of Compressive Sensing (CS) in signal processing is reducing the quantity of data that is acquired for successfully reconstructing the signals. Decreasing the number of coefficients of the acquired images will result in reduced acquisition time i.e. nothing but the duration for which the images are exposed to the MRI apparatus. This paper aims at using optimization algorithms in designing the scanner of the MR integrated with the CS, which results in the reduction of the scan time of the MRI. From a small set of acquired samples, images of satisfactory quality can be obtained. Various Compressive Sensing based optimization algorithms for reconstructing the MRI images are assessed, and a relative comparison is done for further research in this paper.

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