scholarly journals Value of 3D Reconstructions of CT Scans for Calcaneal Fracture Assessment

2016 ◽  
Vol 37 (11) ◽  
pp. 1211-1217 ◽  
Author(s):  
Christina Roll ◽  
Johanna Schirmbeck ◽  
Franz Müller ◽  
Carsten Neumann ◽  
Bernd Kinner
Keyword(s):  
Calcaneal Fracture ◽  
Ct Scans ◽  
3D Reconstructions ◽  
Fracture Assessment

scholarly journals The metopic index: an anthropometric index for the quantitative assessment of trigonocephaly from metopic synostosis

2016 ◽  
Vol 18 (3) ◽  
pp. 275-280 ◽  
Author(s):  
Joanna Y. Wang ◽  
Amir H. Dorafshar ◽  
Ann Liu ◽  
Mari L. Groves ◽  
Edward S. Ahn
Keyword(s):  
Quantitative Assessment ◽  
Surgical Repair ◽  
Preoperative Evaluation ◽  
Ct Scans ◽  
Control Group ◽  
3D Reconstructions ◽  
Metopic Synostosis ◽  
The Mean ◽  
Age Range ◽  
Age And Sex

OBJECTIVE Because the metopic suture normally fuses during infancy, there are varying degrees of severity in head shape abnormalities associated with premature fusion. A method for the objective and reproducible assessment of metopic synostosis is needed to guide management, as current methods are limited by their reliance on aesthetic markers. The object of this study was to describe the metopic index (MI), a simple anthropometric cranial measurement. The measurements can be obtained from CT scans and, more importantly, from palpable cranial landmarks, and the index provides a rapid tool for evaluating patients in both pre- and postoperative settings. METHODS High-resolution head CT scans obtained in 69 patients (age range 0–24 months) diagnosed with metopic craniosynostosis were retrospectively reviewed. Preoperative 3D reconstructions were available in 15 cases, and these were compared with 3D reconstructions of 324 CT scans obtained in a control group of 316 infants (age range 0–24 months) who did not have any condition that might affect head size or shape and also in a subset of this group, comprising 112 patients precisely matched to the craniosynostosis patients with respect to age and sex. Postoperative scans were available and reviewed in 9 of the craniosynostosis patients at a mean time of 7.1 months after surgical repair. 3D reconstructions of these scans were matched with controls based upon age and sex. RESULTS The mean preoperative MI for patients with trigonocephaly was 0.48 (SD 0.05), significantly lower than the mean values of 0.57 (SD 0.04) calculated on the basis of all 324 scans obtained in controls (p < 0.001) and 0.58 (SD 0.04) for the subset of 112 age- and sex-matched controls (p < 0.001). For 7 patients with both pre- and postoperative CT scans available for evaluation, the mean postoperative MI was 0.55 (SD 0.03), significantly greater than their preoperative MIs (mean 0.48 [SD 0.04], p = 0.001) and comparable to the mean MI of the controls (p = 0.30). In 4 patients, clinically obtained postoperative MIs by caliper measurement were comparable to measurements derived from CT (p = 0.141). CONCLUSIONS The MI is a useful measurement of the severity of trigonocephaly in patients with metopic synostosis. This simple quantitative assessment can potentially be used in the clinical setting to guide preoperative evaluation, surgical repair, and postoperative degree of correction.

scholarly journals The Role of 3D Reconstruction True Volume Analysis in Osteochondral Lesions of the Talus

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0012
Author(s):  
Kempland Walley ◽  
Tyler Gonzalez ◽  
Evan Roush ◽  
Kaitlin Saloky ◽  
Ryan Callahan ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Cartilage Damage ◽  
Ct Scans ◽  
Osteochondral Lesions ◽  
Ct Scanner ◽  
3D Reconstructions ◽  
Volume Analysis ◽  
Orthopedic Surgeons ◽  
Damage Stability ◽  
Conventional Ct

Category: Other Introduction/Purpose: Evaluation and management of osteochondral lesions of the talus (OLTs) often warrant advanced imaging studies such as CT and/or MRI. While MRI has its advantages in determining the degree of cartilage damage, stability of the fragment and edema, CT imaging is better delineates the osseous anatomy and extent of the lesion. The latter imaging modality offers increasing acuity and resolution in characterizing the complex osteochondral landscape via three-dimensional (3D) reconstructions. It is possible that orthopedic surgeons may overestimate the size and misinterpret the morphology of OLT from conventional MRI and CT thereby influencing treatment strategies. The purpose of this study is to determine the utility of a novel means to estimate the true-volume of OLTs using 3D reconstructed images and volume analysis. Methods: After IRB approval, an institutional radiology database was queried for patients with OLTs and compatible CT scans between 2011 and 2016. Fourteen patients were found to have OLT compatible with the software used to approximate true-volumes of 3D reconstructed images. 3D reconstructions were created using Mimics software (Materialise, Belgium). From the 14 reconstructed OLTs, 5 were randomly selected for evaluation. 10 orthopedic surgeons independently estimated the volume of these 5 OLTs via standard CT scans. Then 3D reconstructions were made and true-volume (TV) analysis measurements of each OLT were generated. The percent change in volumes from CT were compared to TVs determined from 3D reconstructive analysis. Results: On average the volume calculated by conventional CT scanner grossly overestimated the actual size of the OLTs. The volume calculated on conventional CT scanner overestimated the size of OLTs compared to the 3D TV reconstructed analysis by 285-864%. Conclusion: Our results show that conventional measurements of OLTS with CT grossly overestimates the size of the lesion by up to 8-times the actual lesion size. This overestimation of volumes of the lesion can drastically change surgical planning and may lead to unnecessary costs associated with specific surgical treatments. With the use of our newly defined model for volume measurement in OLTs, we can more accurately predict the exact size of the OLT. This can better guide surgeons to choices both the correct cartilage restoring procedure as well as the need for bone grafting.

CT scans and 3D reconstructions of Florida manatee (Trichechus manatus latirostris) heads and ear bones

2007 ◽  
Vol 228 (1-2) ◽  
pp. 123-135 ◽  
Author(s):  
Marie E. Chapla ◽  
Douglas P. Nowacek ◽  
Sentiel A. Rommel ◽  
Valerie M. Sadler
Keyword(s):  
Ct Scans ◽  
Florida Manatee ◽  
Trichechus Manatus ◽  
3D Reconstructions ◽  
Trichechus Manatus Latirostris

Pedicle stress shielding following growing rod implantation: case report

2019 ◽  
Vol 30 (5) ◽  
pp. 700-704
Author(s):  
Daniel J. Cognetti ◽  
Amer F. Samdani ◽  
Joshua M. Pahys ◽  
Mari L. Groves ◽  
Steven W. Hwang
Keyword(s):  
Case Report ◽  
Spinal Column ◽  
Stress Shielding ◽  
Ct Scans ◽  
Skeletally Immature ◽  
3D Reconstructions ◽  
Severe Scoliosis ◽  
Growing Rod ◽  
Infantile Idiopathic Scoliosis ◽  
Pedicle Morphology

Growing rod surgery for skeletally immature patients helps correct severe scoliosis while allowing continued spinal column growth. Previous reports have studied vertebral body changes following growing rod surgery, but there are currently no published reports on alterations in pedicle morphology. Given the potential need for definitive spinal fusion with pedicle screw instrumentation, an awareness of changes in pedicle morphology is critical. A morphometric analysis of pedicles was performed using 3D reconstructions of 3 CT scans (preoperative and at 3 and 6 years) obtained in a young girl with infantile idiopathic scoliosis (T7 apex) who underwent unilateral rib-to-spine growing rod (2nd–4th ribs to L1) implantation with lengthening every 6 months for 6 years. The pedicle widths on the growing rod side from T5 to T9 (apex ± 2) were all smaller at 6 years postoperatively than preoperatively, while the same-level pedicles opposite the device significantly increased in width. These findings support anecdotal intraoperative reports by surgeons and provide evidence of pedicle stress shielding due to growing rod distraction and force deprivation.

scholarly journals Why canines induce resorption of neighboring roots? An imaging correlation

2019 ◽  
Vol 24 (1) ◽  
pp. 27-33
Author(s):  
Alberto Consolaro ◽  
Omar Hadaya ◽  
Taisa Maeshiro Estorce
Keyword(s):  
Clinical Management ◽  
Clinical Case ◽  
Root Resorption ◽  
Ct Scans ◽  
Imaging Findings ◽  
3D Reconstructions

ABSTRACT Despite the explanations about the mechanisms and reasons why dental follicles of unerupted maxillary canines do not cause root resorption in neighboring teeth, questions remain about the time expected for this event and the lack of protocols for preventive clinical management, which may serve as insights for further studies. Here, these mechanisms are correlated with imaging findings of CT scans and 3D reconstructions of a typical clinical case.

Improved 3-D reconstruction using stereo computer graphics and multiple tilt EM images

1995 ◽  
Vol 53 ◽  
pp. 630-631
Author(s):  
Lee D. Peachey ◽  
Lou Fodor ◽  
John C. Haselgrove ◽  
Stanley M. Dunn ◽  
Junqing Huang
Keyword(s):  
Computer Graphics ◽  
High Performance ◽  
Transverse Section ◽  
Three Dimensional ◽  
Stereo Pair ◽  
3D Reconstructions ◽  
Video Cameras ◽  
Biological Objects ◽  
Microscope Images ◽  
High Performance Computer

Stereo pairs of electron microscope images provide valuable visual impressions of the three-dimensional nature of specimens, including biological objects. Beyond this one seeks quantitatively accurate models and measurements of the three dimensional positions and sizes of structures in the specimen. In our laboratory, we have sought to combine high resolution video cameras with high performance computer graphics systems to improve both the ease of building 3D reconstructions and the accuracy of 3D measurements, by using multiple tilt images of the same specimen tilted over a wider range of angles than can be viewed stereoscopically. Ultimately we also wish to automate the reconstruction and measurement process, and have initiated work in that direction.Figure 1 is a stereo pair of 400 kV images from a 1 micrometer thick transverse section of frog skeletal muscle stained with the Golgi stain. This stain selectively increases the density of the transverse tubular network in these muscle cells, and it is this network that we reconstruct in this example.

Two-Dimensional Crystallization of Tetanus Toxin

1985 ◽  
Vol 43 ◽  
pp. 528-529
Author(s):  
Jeffry A. Reidler ◽  
John P. Robinson
Keyword(s):  
Electron Microscopy ◽  
Tetanus Toxin ◽  
Structural Information ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Membrane Interface ◽  
3D Reconstructions ◽  
Cellular Receptors ◽  
Computer Reconstruction ◽  
2D Crystals

We have prepared two-dimensional (2D) crystals of tetanus toxin using procedures developed by Uzgiris and Kornberg for the directed production of 2D crystals of monoclonal antibodies at an antigen-phospholipid monolayer interface. The tetanus toxin crystals were formed using a small mole fraction of the natural receptor, GT1, incorporated into phosphatidyl choline monolayers. The crystals formed at low concentration overnight. Two dimensional crystals of this type are particularly useful for structure determination using electron microscopy and computer image refinement. Three dimensional (3D) structural information can be derived from these crystals by computer reconstruction of photographs of toxin crystals taken at different tilt angles. Such 3D reconstructions may help elucidate the mechanism of entry of the enzymatic subunit of toxins into cells, particularly since these crystals form directly on a membrane interface at similar concentrations of ganglioside GT1 to the natural cellular receptors.

Structure of rattlesnake venom lectin determined by single particle high-resolution electron microscopy

1996 ◽  
Vol 54 ◽  
pp. 62-63
Author(s):  
Peter D. Moisiuk ◽  
Daniel R. Beniac ◽  
Ross A. Ridsdale ◽  
Martin Young ◽  
Bhushan Nagar ◽  
...  
Keyword(s):  
High Resolution Electron Microscopy ◽  
Lipid Monolayer ◽  
Outer Diameter ◽  
X Ray Diffraction ◽  
Single Particles ◽  
Crotalus Atrox ◽  
3D Reconstructions ◽  
X Ray ◽  
Rattlesnake Venom ◽  
Covalently Linked

Venom from the rattlesnake Crotalus atrox contains a mixture of enzymes that induce a localized effect leading to hemorrhaging, necrosis and edema. As a member of the crotalid family of snake venoms, Crotalus atrox venom contains a C-type lectin that will agglutinate blood cells in a Ca2+-dependent fashion. The lectin is a hydrophilic protein, consisting of two covalently linked, 135 amino acid residues, identical subunits that are rich in aspartic acid, glutamic acid and lysine. Sequence homology with known carbohydrate recognition domains (CRDs) indicates that rattlesnake venom lectin (RSLV) contains a CRD motif that is not linked to accessory domains. Preliminary X-ray diffraction and sedimentation analysis has indicated that lectin from Crotalus atrox forms decamers composed of two five-fold symmetric pentamers. Single particles of RSVL imaged at – 171°C displayed two distinct orientations on the specimen support (Figure a) following incubation in a crystallization Teflon well, coated with a lipid monolayer consisting of phosphatidylcholine and monosialoganglioside. When lying in an end-on orientation, the lectin exhibited a “pentagonal ring” with an outer diameter of 6.7 nm and an inner hollow core of 1.7 nm. A side orientation was also seen, whereby a thickness of 5.8 nm was measured for the lectin. Image processing of 2280 single particles placed in 100 classes (Figure b) led to 3D reconstructions of RSVL (Figure c). Density limited 3D reconstructions showed the lectin to be made of two five-fold symmetrical rings covalently linked between the five subunits that constitute each ring of this homodimer. These results are consistent with sedimentation and preliminary X-ray diffraction analysis on the shape of RSVL and provide the framework for structural verification by 2D electron crystallography.

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