Optical-Based Analysis of Soft Tissue Structures

Abstract Introduction This pilot study explores whether a human Thiel-embalmed temporal bone is suitable for generating an accurate and complete data set with micro-computed tomography (micro-CT) and whether solid iodine-staining improves visualization and facilitates segmentation of middle ear structures. Methods A temporal bone was used to verify the accuracy of the imaging by first digitally measuring the stapes on the tomography images and then physically under the microscope after removal from the temporal bone. All measurements were compared with literature values. The contralateral temporal bone was used to evaluate segmentation and three-dimensional (3D) modeling after iodine staining and micro-CT scanning. Results The digital and physical stapes measurements differed by 0.01–0.17 mm or 1–19%, respectively, but correlated well with the literature values. Soft tissue structures were visible in the unstained scan. However, iodine staining increased the contrast-to-noise ratio by a factor of 3.7 on average. The 3D model depicts all ossicles and soft tissue structures in detail, including the chorda tympani, which was not visible in the unstained scan. Conclusions Micro-CT imaging of a Thiel-embalmed temporal bone accurately represented the entire anatomy. Iodine staining considerably increased the contrast of soft tissues, simplified segmentation and enabled detailed 3D modeling of the middle ear.

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3DMRI Modeling of Thin and Spatially Complex Soft Tissue Structures without Shrinkage: Lamprey Myosepta as an Example

The Anatomical Record ◽

10.1002/ar.23857 ◽

2018 ◽

Vol 301 (10) ◽

pp. 1745-1763

Author(s):

Bradley M. Wood ◽

Guang Jia ◽

Owen Carmichael ◽

Kevin Mcklveen ◽

Dominique G. Homberger

Keyword(s):

Soft Tissue ◽

Tissue Structures

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Defining Norms for the Upper and Lower Lips of the Himachali Ethnic Population: A Cephalometric Study

Dental Journal of Advance Studies ◽

10.1055/s-0038-1672068 ◽

2016 ◽

Vol 04 (03) ◽

pp. 189-194

Author(s):

Isha Aggarwal ◽

Manu Wadhawan

Keyword(s):

Soft Tissue ◽

Ethnic Groups ◽

Normal Subjects ◽

Facial Features ◽

Ethnic Population ◽

Soft Tissue Profile ◽

Lateral Cephalograms ◽

Males And Females ◽

Tissue Structures ◽

Cephalometric Study

Abstract Introduction: The great variance in soft-tissue drape of the human face complicates accurate assessment of the soft-tissue profile and it is a known fact that facial features of different ethnic groups differ significantly. This study was undertaken to establish soft tissue norms for Himachali ethnic population. Method: The sample comprised lateral cephalograms taken in natural head position of 100 normal subjects (50 males, 50 females). The cephalograms were analyzed by Arnett soft tissue cephalometric analysis for orthodontic diagnosis and treatment planning. The Student t test was used to compare the means of the 2 groups. Results: Statistically significant differences were found between Himachali males and females in certain key parameters. Males have thicker soft-tissue structures than females. Whereas females have greater interlabial gap when compared with Himachali males. When compared with other ethnic groups, Himachali subjects have thicker soft tissue structures. Conclusions: Statistically significant differences were found between Himachali males and females in certain key parameters. Differences were also noted between other ethnic groups and Himachali faces.

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Prediction of TKR Function Using Specimen Specific Robotically Calibrated Knee Models

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80293 ◽

2012 ◽

Cited By ~ 1

Author(s):

Eik Siggelkow ◽

Iris Sauerberg ◽

Francesco Benazzo ◽

Marc Bandi

Keyword(s):

Soft Tissue ◽

Degrees Of Freedom ◽

Knee Kinematics ◽

Computer Models ◽

Industrial Robots ◽

Experimental Investigations ◽

Tissue Properties ◽

Tissue Structures ◽

Kinematics And Kinetics

Passive knee kinematics and kinetics following total knee replacement (TKR) are dependent on the topology of the component joint surfaces as well as the properties of the passive soft tissue structures (ligaments and capsule). Recently, explicit computer models have been used for the prediction of knee joint kinematics based on experimental investigations [1]. However, most of these models replicate experimental knee simulators [2], which simulate soft tissue structures using springs or elastomeric structures. New generations of experimental setups deploy industrial robots for measuring kinematics and kinetics in six degrees of freedom as well as the contribution of soft tissue structures. Based on these experiments, accurate soft tissue properties are available for use in computer models to aid more realistic predictions of kinematics. Final evidence of the quality of the kinematic predictions from these computer models can be provided by direct validation of the models against experimental data. Therefore, the objective of this study was to use in vitro robotic test data to develop, verify, and validate specimen specific virtual models suitable for predicting laxity and kinematics of the reconstructed knee.

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Percutaneous Posterior to Anterior Screw Fixation of the Talar Neck

Foot & Ankle Orthopaedics ◽

10.1177/2473011418s00204 ◽

2018 ◽

Vol 3 (3) ◽

pp. 2473011418S0020

Author(s):

Cesar de Cesar Netto ◽

Lauren Roberts ◽

Alexandre Godoy Dos Santos ◽

Jackson Staggers ◽

Sung Lee ◽

...

Keyword(s):

Soft Tissue ◽

Achilles Tendon ◽

Tissue Injury ◽

Soft Tissue Injury ◽

Injury Rate ◽

Posterolateral Approach ◽

Flexor Hallucis Longus ◽

Peroneal Tendons ◽

The Mean ◽

Tissue Structures

Category: Trauma Introduction/Purpose: Fractures of the talar neck and body can be fixed with percutaneously placed screws directed from anterior to posterior or posterior to anterior. The latter has been found to be biomechanically and anatomically superior. Percutaneous pin and screw placement poses anatomic risks for posterolateral and posteromedial neurovascular and tendinous structures. The objective of this study was to enumerate the number of trials for proper placement of two parallel screws and to determine the injury rate to neurovascular and tendinous structures. Methods: Eleven fresh frozen cadaver limbs were used. 2.0 mm guide wires from the Stryker (Selzach, Switzerland) 5.0-mm headless cannulated set were percutaneously placed (under fluoroscopic guidance) into the distal posterolateral aspect of the ankle. All surgical procedures were performed by a fellowship-trained foot and ankle surgeon. Malpositioned pins were left intact to allow later assessment of soft tissue injury. The number of guide wires needed to achieve an acceptable positioning of the implant was noted. Acceptable positioning was defined as in line with the talar neck axis in both AP and lateral fluoroscopic views. After a layered dissection from the skin to the tibia, we evaluated neurovascular and tendinous injuries, and measured the shortest distance between the closest guide pin and the soft tissue structures, using a precision digital caliper. Results: The mean number of guide wires needed to achieve acceptable positioning for 2 parallel screws was 2.91 ± 0.70 (range, 2 - 5). The mean distances between the closest guide pin and the soft tissue structures of interest were: Achilles tendon, 0.53 ± 0.94 mm; flexor hallucis longus tendon, 6.62 ± 3.24 mm; peroneal tendons, 7.51 ± 2.92 mm; and posteromedial neurovascular bundle, 11.73 ± 3.48 mm. The sural bundle was injured in all the specimens, with 8/11 (72.7%) in direct contact with the guide pin and 3/11 (17.3%) having been transected. The peroneal tendons were transected in 1/11 (9%) of the specimens. The Achilles tendon was in contact with the guide pin in 6/11 (54.5%) specimens and transected in 2/11 (18.2%) specimens. Conclusion: The placement of posterior to anterior percutaneous screws for talar neck fixation is technically demanding and multiple guide pins are needed. Our cadaveric study showed that important tendinous and neurovascular structures are in close proximity with the guide pins and that the sural bundle was injured in 100% of the cases. We advise performing a formal small posterolateral approach for proper visualization and retraction of structures at risk. Regardless, adequate patient education about the high risk of injury from this procedure is crucial.

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Ankle fusion percutaneous home run screw fixation: Technical aspects and soft tissue structures at risk

The Foot ◽

10.1016/j.foot.2019.05.004 ◽

2019 ◽

Vol 40 ◽

pp. 39-42

Author(s):

L. Roberts ◽

A.L. Godoy-Santos ◽

P.W. Hudson ◽

S. Phillips ◽

D.R.C. Nishikawa ◽

...

Keyword(s):

At Risk ◽

Soft Tissue ◽

Screw Fixation ◽

Technical Aspects ◽

Ankle Fusion ◽

Tissue Structures

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Realistic 3D Computer Model of the Gerbil Middle Ear, Featuring Accurate Morphology of Bone and Soft Tissue Structures

Journal of the Association for Research in Otolaryngology ◽

10.1007/s10162-011-0281-4 ◽

2011 ◽

Vol 12 (6) ◽

pp. 681-696 ◽

Cited By ~ 31

Author(s):

Jan A. N. Buytaert ◽

Wasil H. M. Salih ◽

Manual Dierick ◽

Patric Jacobs ◽

Joris J. J. Dirckx

Keyword(s):

Soft Tissue ◽

Middle Ear ◽

Computer Model ◽

Tissue Structures ◽

3D Computer Model

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DIGITAL RECONSTRUCTION OF SOFT-TISSUE STRUCTURES IN FOSSILS

The Paleontological Society Papers ◽

10.1017/scs.2017.10 ◽

2016 ◽

Vol 22 ◽

pp. 101-117 ◽

Cited By ~ 7

Author(s):

Stephan Lautenschlager

Keyword(s):

Soft Tissue ◽

Soft Tissues ◽

Imaging Techniques ◽

Analytical Techniques ◽

Computational Imaging ◽

Whole Body ◽

Element Analysis ◽

Digital Reconstruction ◽

New Information ◽

Tissue Structures

AbstractIn the last two decades, advances in computational imaging techniques and digital visualization have created novel avenues for the study of fossil organisms. As a result, paleontology has undergone a shift from the pure study of physically preserved bones and teeth, and other hard tissues, to using virtual computer models to study specimens in greater detail, restore incomplete specimens, and perform biomechanical analyses. The rapidly increasing application of these techniques has further paved the way for the digital reconstruction of soft-tissue structures, which are rarely preserved or otherwise available in the fossil record. In this contribution, different types of digital soft-tissue reconstructions are introduced and reviewed. Provided examples include methodological approaches for the reconstruction of musculature, endocranial components (e.g., brain, inner ear, and neurovascular structures), and other soft tissues (e.g., whole-body and life reconstructions). Digital techniques provide versatile tools for the reconstruction of soft tissues, but given the nature of fossil specimens, some limitations and uncertainties remain. Nevertheless, digital reconstructions can provide new information, in particular if interpreted in a phylogenetically grounded framework. Combined with other digital analytical techniques (e.g., finite element analysis [FEA], multibody dynamics analysis [MDA], and computational fluid dynamics [CFD]), soft-tissue reconstructions can be used to elucidate the paleobiology of extinct organisms and to test competing evolutionary hypotheses.

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