Cholesteatoma in three dimensions: a teaching tool and an aid to improved pre-operative consent

2009 ◽  
Vol 124 (2) ◽  
pp. 126-131 ◽  
Author(s):  
D P Morris ◽  
R G Van Wijhe
Keyword(s):  
Temporal Bone ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Teaching Tool ◽  
Surgical Experience ◽  
Teaching Programme ◽  
Computed Tomography Images ◽  
Three Dimensional Models ◽  
Temporal Bones ◽  
User Friendly

AbstractBackground:Otological surgeons face two recurring challenges. Firstly, we must foster an appreciation of the complex, three-dimensional anatomy of the temporal bone in order to enable our trainees to operate safely and independently. Secondly, we must explain to our patients the necessity for surgery which carries the potential for serious complication.Methods:Amira® software was applied to pre-operative computed tomography images of temporal bones with cholesteatoma, to create three-dimensional computer images. Normal structures and cholesteatoma were displayed in a user-friendly, interactive format, allowing both trainee and patient to visualise disease and important structures within the temporal bone.Results:Three cases, and their three-dimensional computer models are presented. Zoom, rotation and transparency functions complemented the three-dimensional effect.Conclusion:These three-dimensional models provided a useful adjunct to cadaveric temporal bone dissection and surgical experience for our residents' teaching programme. Also, patients with cholesteatoma reported a better understanding of their pre-operative condition when the models were used during the consenting process.

scholarly journals Evaluation of the Effect of the Sulcus Angle and Lateral to Medial Facet Ratio of the Patellar Groove on Patella Tracking in Aging Subjects with Stable Knee Joint

2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Jianghui Qin ◽  
Dongyang Chen ◽  
Zhihong Xu ◽  
Dongquan Shi ◽  
Jin Dai ◽  
...  
Keyword(s):  
Lower Limb ◽  
Lateral Displacement ◽  
Three Dimensional ◽  
Trochlear Groove ◽  
Patellar Tilt ◽  
Sulcus Angle ◽  
Lateral Tilt ◽  
Computed Tomography Images ◽  
Three Dimensional Models ◽  
Patella Tracking

Purpose.To determine whether the sulcus angle and the lateral to medial facet ratio correlate with patella lateral displacement and tilt in patients without patella instability.Methods.Computed tomography images of the lower limb of 64 patients without known arthropathy were collected. Three-dimensional models of the lower limb with a unified coordinate system were rebuilt by using Mimics software. The sulcus angle, lateral to medial facet ratio, lateral trochlear inclination of the patellar groove, tibial tuberosity-trochlear groove (TT-TG) distance, bisect offset index, and lateral tilt of the patella were measured. Pearson’s correlation test was used to determine the relationship between the aforementioned parameters.Results.Data from 51 patients were analyzed. The sulcus angle was negatively correlated with lateral tilt inclination (p<0.001,r=0.8406) and positively correlated with the bisect offset index (p=0.003,r=0.634) and patellar tilt (p=0.03,r=0.551); the lateral to medial facet ratio was positively correlated with TT-TG distance (p=0.003,r=0.643) and bisect offset index (p=0.026,r=0.559).Conclusion.The sulcus angle and lateral to medial facet ratio of the patellar groove can influence patella tracking in patients with stable knee joints.

Implications of rotational kinematics for the oculomotor system in three dimensions

1987 ◽  
Vol 58 (4) ◽  
pp. 832-849 ◽  
Author(s):  
D. Tweed ◽  
T. Vilis
Keyword(s):  
Three Dimensional ◽  
Oculomotor System ◽  
Three Dimensions ◽  
Eye Position ◽  
Head Velocity ◽  
Listing’S Law ◽  
Indirect Path ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
Eye Velocity

1. This paper develops three-dimensional models for the vestibuloocular reflex (VOR) and the internal feedback loop of the saccadic system. The models differ qualitatively from previous, one-dimensional versions, because the commutative algebra used in previous models does not apply to the three-dimensional rotations of the eye. 2. The hypothesis that eye position signals are generated by an eye velocity integrator in the indirect path of the VOR must be rejected because in three dimensions the integral of angular velocity does not specify angular position. Computer simulations using eye velocity integrators show large, cumulative gaze errors and post-VOR drift. We describe a simple velocity to position transformation that works in three dimensions. 3. In the feedback control of saccades, eye position error is not the vector difference between actual and desired eye positions. Subtractive feedback models must continuously adjust the axis of rotation throughout a saccade, and they generate meandering, dysmetric gaze saccades. We describe a multiplicative feedback system that solves these problems and generates fixed-axis saccades that accord with Listing's law. 4. We show that Listing's law requires that most saccades have their axes out of Listing's plane. A corollary is that if three pools of short-lead burst neurons code the eye velocity command during saccades, the three pools are not yoked, but function independently during visually triggered saccades. 5. In our three-dimensional models, we represent eye position using four-component rotational operators called quaternions. This is not the only algebraic system for describing rotations, but it is the one that best fits the needs of the oculomotor system, and it yields much simpler models than do rotation matrix or other representations. 6. Quaternion models predict that eye position is represented on four channels in the oculomotor system: three for the vector components of eye position and one inversely related to gaze eccentricity and torsion. 7. Many testable predictions made by quaternion models also turn up in models based on other mathematics. These predictions are therefore more fundamental than the specific models that generate them. Among these predictions are 1) to compute eye position in the indirect path of the VOR, eye or head velocity signals are multiplied by eye position feedback and then integrated; consequently 2) eye position signals and eye or head velocity signals converge on vestibular neurons, and their interaction is multiplicative.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Review of temporal bone dissection teaching: how it was, is and will be

2009 ◽  
Vol 124 (2) ◽  
pp. 119-125 ◽  
Author(s):  
A P George ◽  
R De
Keyword(s):  
Virtual Reality ◽  
Temporal Bone ◽  
Three Dimensional ◽  
Review Of The Literature ◽  
Anatomical Dissection ◽  
Pubmed Database ◽  
Fresh Frozen ◽  
History Of ◽  
Temporal Bone Anatomy ◽  
Three Dimensional Models

AbstractObjective:We aimed to review the history of anatomical dissection, and to examine how modern educational techniques will change the way temporal bone dissection is taught to otolaryngology trainees.Method:Review of the literature using Medline, Embase and PubMed database searches.Results:Temporal bone anatomy has traditionally been taught using cadaveric specimens. However, resources such as three-dimensional reconstructed models and ‘virtual reality’ temporal bone simulators have a place in educating the otolaryngology trainee.Conclusion:We should encourage the use of fresh frozen cadaveric temporal bone specimens for future otologists. Artificial three-dimensional models and virtual reality temporal bone simulators can be used to educate junior trainees, thus conserving the scarce resource of cadaveric bones.

A navigation system for shoulder arthroscopic surgery

2007 ◽  
Vol 221 (7) ◽  
pp. 801-812 ◽  
Author(s):  
K Tyryshkin ◽  
P Mousavi ◽  
M Beek ◽  
R E Ellis ◽  
D R Pichora ◽  
...  
Keyword(s):  
Navigation System ◽  
Shoulder Arthroscopy ◽  
Dimensional Space ◽  
Arthroscopic Surgery ◽  
Three Dimensional ◽  
Surgical Instruments ◽  
Surface Model ◽  
Ultrasound Images ◽  
Computed Tomography Images ◽  
Three Dimensional Models

The general framework and experimental validation of a novel navigation system designed for shoulder arthroscopy are presented. The system was designed to improve the surgeon's perception of the three-dimensional space within the human shoulder. Prior to surgery, a surface model of the shoulder was created from computed tomography images. Intraoperatively optically tracked arthroscopic instruments were calibrated. The surface model was then registered to the patient using tracked freehand ultrasound images taken from predefined landmark regions on the scapula. Three-dimensional models of the surgical instruments were displayed, in real time, relative to the surface model in a user interface. Laboratory experiments revealed only small registration and calibration errors, with minimal time needed to complete the intraoperative tasks.

scholarly journals Budding yeast chromatin is dispersed in a crowded nucleoplasm in vivo

2016 ◽  
Vol 27 (21) ◽  
pp. 3357-3368 ◽  
Author(s):  
Chen Chen ◽  
Hong Hwa Lim ◽  
Jian Shi ◽  
Sachiko Tamura ◽  
Kazuhiro Maeshima ◽  
...  
Keyword(s):  
Budding Yeast ◽  
Three Dimensional ◽  
Chromatin Organization ◽  
Three Dimensions ◽  
Yeast Saccharomyces Cerevisiae ◽  
Nuclear Structures ◽  
Three Dimensional Models ◽  
Electron Cryotomography ◽  
Fundamental Units

Chromatin organization has an important role in the regulation of eukaryotic systems. Although recent studies have refined the three-dimensional models of chromatin organization with high resolution at the genome sequence level, little is known about how the most fundamental units of chromatin—nucleosomes—are positioned in three dimensions in vivo. Here we use electron cryotomography to study chromatin organization in the budding yeast Saccharomyces cerevisiae. Direct visualization of yeast nuclear densities shows no evidence of 30-nm fibers. Aside from preribosomes and spindle microtubules, few nuclear structures are larger than a tetranucleosome. Yeast chromatin does not form compact structures in interphase or mitosis and is consistent with being in an “open” configuration that is conducive to high levels of transcription. From our study and those of others, we propose that yeast can regulate its transcription using local nucleosome–nucleosome associations.

scholarly journals NUMERICAL ANALYSIS OF SHORT AND LONG INSTRUMENTATION IN THE TREATMENT OF THORACOLUMBAR FRACTURES CONSIDERING THE LIGAMENTOUS PORTION

2019 ◽  
Vol 18 (2) ◽  
pp. 144-150
Author(s):  
André Rafael Hubner ◽  
Danilo Mourão Ribeiro ◽  
Eduardo Dassoler ◽  
Daniel Gasparin ◽  
Charles Leonardo Israel ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Thoracolumbar Spine ◽  
Three Dimensional ◽  
Maximum Tensile Stress ◽  
Thoracolumbar Fractures ◽  
Level Of Evidence ◽  
Safety Coefficient ◽  
Computed Tomography Images ◽  
Three Dimensional Models ◽  
Anterior Posterior

ABSTRACT Objective: This study aims to numerically evaluate the surgical treatment of thoracolumbar fractures, comparing the strengths between the long and short fixations using the pedicle of the fractured vertebra, taking into account the supraspinous, intertransverse, and anterior longitudinal ligaments. Methods: A numerical analysis of the techniques of long and short fixation of a thoracolumbar spine fracture was performed using computed tomography images that were converted into three-dimensional models and analyzed through the ANSYS program. The two types of treatments were analyzed considering the tensions generated in the immediate postoperative period, when the fracture has not yet been consolidated. The anterior, posterior, supraspinal and intertransverse longitudinal ligaments were added, in addition to considering different vertebral geometries. Results: Taking into account that the maximum tensile stress of the material used in the metal implant, in the case of titanium, was 960 MPa, the highest tension found in the analysis of the short instrumentation was 346.83 MPa, reaching only 36.13% of the load the material supports, being, therefore, within a safety limit. The analysis performed in the spine with long instrumentation showed the highest tension value of 229.22 MPa. Conclusions: Considering the values found and the resistance of the synthesis material used, the short and long fixation can be considered in the treatment of thoracolumbar fractures with similarity and a good safety coefficient. Level of Evidence III; Case-Control.

Temporal bone Pneumatization in Otosclerosis

2008 ◽  
Vol 139 (6) ◽  
pp. 850-853 ◽  
Author(s):  
Daniel T. Ganc ◽  
Robert W. Jyung
Keyword(s):  
Temporal Bone ◽  
Statistical Significance ◽  
Three Dimensional ◽  
Neck Surgery ◽  
Adult Patients ◽  
Control Group ◽  
Test Analysis ◽  
Temporal Bone Pneumatization ◽  
History Of ◽  
Temporal Bones

Objectives To determine whether there is a difference in the pneumatization of temporal bones with otosclerosis versus normal temporal bones. Methods A retrospective study of 46 ears from 24 adult patients with otosclerosis and 64 ears from 47 adult patients in a control group. The study group included temporal bone CT scans available from patients with otosclerosis. The control group consisted of patients who had temporal bone CTs for reasons likely unrelated to a history of middle ear disease. Data were obtained with a virtual reality system that allows three-dimensional manipulation and analysis. Results The temporal bone pneumatization for the otosclerosis group was 4.82 ± 2.27 cm3 vs 6.06 ± 2.71 cm3 for the control group. Two-sample t test analysis revealed no statistical significance ( P = 0.059) between pneumatization in the control vs otosclerosis groups. Conclusion There is no difference in temporal bone pneumatization between patients with otosclerosis and a control population. Therefore, temporal bone pneumatization by itself is not an adequate explanation for the apparent protective effect of otosclerosis against otitis media. © 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

scholarly journals Structural features of the fly chromatin colors revealed by automatic three-dimensional modeling.

2016 ◽  
Author(s):  
François Serra ◽  
Davide Baù ◽  
Guillaume Filion ◽  
Marc A. Marti-Renom
Keyword(s):  
Spatial Organization ◽  
Three Dimensional ◽  
Structural Features ◽  
Three Dimensions ◽  
Chromosome Conformation ◽  
Three Dimensional Modeling ◽  
Genomic Technologies ◽  
A Genome ◽  
Contact Data ◽  
Three Dimensional Models

The sequence of a genome is insufficient to understand all genomic processes carried out in the cell nucleus. To achieve this, the knowledge of its three- dimensional architecture is necessary. Advances in genomic technologies and the development of new analytical methods, such as Chromosome Conformation Capture (3C) and its derivatives, now permit to investigate the spatial organization of genomes. However, inferring structures from raw contact data is a tedious process for shortage of available tools. Here we present TADbit, a computational framework to analyze and model the chromatin fiber in three dimensions. To illustrate the use of TADbit, we automatically modeled 50 genomic domains from the fly genome revealing differential structural features of the previously defined chromatin colors, establishing a link between the conformation of the genome and the local chromatin composition. More generally, TADbit allows to obtain three-dimensional models ready for visualization from 3C-based experiments and to characterize their relation to gene expression and epigenetic states. TADbit is open-source and available for download from http://www.3DGenomes.org.

scholarly journals Impact of temporal bone dissection on the understanding anatomy of the ear among medical students

2018 ◽  
Vol 4 (6) ◽  
pp. 1489
Author(s):  
K. C. Prasad ◽  
Prathyusha K. ◽  
Shreeharsha Maruvala ◽  
Harshita T. R. ◽  
Indu Varsha Gopi ◽  
...  
Keyword(s):  
Medical Students ◽  
Temporal Bone ◽  
Three Dimensional ◽  
Operative Procedures ◽  
Research Centre ◽  
Medical College ◽  
Group I ◽  
Group Ii ◽  
Temporal Bones ◽  
The Impact

<p class="abstract">The aim was to study the impact of temporal bone dissection demonstrations on understanding anatomy of the ear among medical students. During a period of six months from October 2017 to March 2018, 10 cadaveric temporal bones dissections were demonstrated using ZEISS microscope and in the presence of medical students headed by a Consultant Otolaryngologist in the department of ENT, Sri Devaraj URS Medical College and Research Centre, Kolar. Anatomy of the middle ear and inner ear and various operative procedures were demonstrated. The students were divided into 2 groups. Group I comprised students who attended the temporal bone dissection and Group II included those who didn’t attend dissection. After the session both the groups were assessed by the consultant. Scores were given to the group individuals based on the ability to answer the questions. 10 Temporal bone dissections were demonstrated in 6 months period to medical students who were divided into 2 groups based on their attendance of the demonstration. The students of both groups were assessed. Scores were given by Likert scale-5point scale question. The results of our study proved that those students who attended the temporal bone dissection (Group-I) had better understanding of the anatomy and operative procedures of the ear as compared to students in group II. Demonstration of temporal bone dissection to the medical students had a good impact on their understanding of the three dimensional anatomy of the ear.</p>

Computer-Aided Three-Dimensional Reconstruction and Measurement of the Vestibular End-Organs

1988 ◽  
Vol 98 (3) ◽  
pp. 195-202 ◽  
Author(s):  
Akira Takagi ◽  
Isamu Sando ◽  
Akira Takagi ◽  
Isamu Sando
Keyword(s):  
Temporal Bone ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Small Computer ◽  
Lateral Semicircular Canal ◽  
3 Dimensional ◽  
Dimensional Reconstruction ◽  
Vestibular Endorgans ◽  
Length And Area ◽  
Bone Structures

It is very valuable for temporal bone morphologists to be able to recognize temporal bone serial sections in three dimensions and to be able to measure temporal bone structures three-dimensionally. We can now do 3-dimensional reconstruction to visualize the structures of vestibular endorgans (utricular and saccular maculae) and measure these endorgans in space by means of a small computer system and software that we developed. As well as obtaining the dimensions—such as length and area—of the utricular and saccular maculae, we also found that (1) most of the utricular macula lies in one plane, which is the same as the plane of the lateral semicircular canal, (2) the saccular macula is shaped like part of a sphere, and (3) the angle between the two maculae is less than a right angle. Such knowledge is indispensable to the evaluation of the function of the utricular and saccular maculae.)

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