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1.
Am J Orthod Dentofacial Orthop ; 159(1): e49-e58, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357762

RESUMO

INTRODUCTION: The midsagittal plane (MSP) is the foundation for 3-dimensional (3D) cephalometric analyses. This article aimed to provide a protocol to construct a reliable and accurate MSP for 3D cephalometric craniofacial analysis. METHODS: Cone-beam computed tomography data of 16 adult patients without obvious bilateral asymmetry were collected. The model of the anterior cranial base and sphenoid bone was constructed, and the candidate MSP was determined on the basis of the symmetry of this model. Intraclass correlation coefficients were used to assess intra- and interexaminer reliability of the candidate MSP. To investigate the accuracy of this candidate MSP, we constructed a true plane of symmetry of craniomaxillofacial structure and a control plane on the basis of 3 cranial midline points. We then compared these with the candidate MSP. RESULTS: This candidate MSP resembled the true plane of symmetry with all the mean absolute errors <1 mm, and all the absolute errors for the candidate MSP were significantly smaller than the control plane (P ≤0.002). The relative intra- and interexaminer reliability for this candidate MSP was almost perfect (intraclass correlation coefficients >0.9). CONCLUSIONS: The candidate MSP constructed using this method was thought to be reliable and accurate for 3D cephalometric analysis in patients without obvious cranial asymmetry.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Adulto , Pontos de Referência Anatômicos/diagnóstico por imagem , Cefalometria , Humanos , Reprodutibilidade dos Testes , Base do Crânio/diagnóstico por imagem
2.
Oral Dis ; 27(1): 14-20, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32881177

RESUMO

OBJECTIVES: In case of surgical removal of oral squamous cell carcinomas, a resection of mandibular bone is frequently part of the treatment. Nowadays, such resections frequently include the application of 3D virtual surgical planning (VSP) and guided surgery techniques. In this paper, current methods for 3D VSP leads for optimisation of the workflow, and patient-specific application of guides and implants are reviewed. RECENT FINDINGS: Current methods for 3D VSP enable multi-modality fusion of images. This fusion of images is not restricted to a specific software package or workflow. New strategies for 3D VSP in Oral and Maxillofacial Surgery include finite element analysis, deep learning and advanced augmented reality techniques. These strategies aim to improve the treatment in terms of accuracy, predictability and safety. CONCLUSIONS: Application of the discussed novel technologies and strategies will improve the accuracy and safety of mandibular resection and reconstruction planning. Accurate, easy-to-use, safe and efficient three-dimensional VSP can be applied for every patient with malignancies needing resection of the mandible.


Assuntos
Mandíbula , Cirurgia Bucal , Humanos , Imageamento Tridimensional , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia
3.
Life Sci ; 264: 118710, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33144188

RESUMO

AIMS: Hepatic venous pressure gradient (HVPG) is critical for staging and prognosis prediction of portal hypertension (PH). However, HVPG measurement has limitations (e.g., invasiveness). This study examined the value of non-invasive, imaging-based approaches including magnetic resonance elastography (MRE) and intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) for the prediction of HVPG in a porcine model of liver cirrhosis and PH. MAIN METHODS: Male Bama miniature pigs were used to establish a porcine model of liver cirrhosis and PH induced by embolization. They were randomly assigned to an experimental group (n = 12) and control group (n = 3). HVPG was examined before and after transjugular intrahepatic portosystemic shunt (TIPS). MRE and IVIM-DWI were performed to obtain quantitative parameters including liver stiffness (LS) in MRE, tissue diffusivity (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) in IVIM-DWI. The correlation between HVPG and the parameters was assessed. KEY FINDINGS: LS values were significantly greater in the experimental group, while f values were significantly decreased at 4, 8, and 12 weeks after embolization compared to the control group. Furthermore, HVPG was significantly lower immediately after versus before TIPS. In parallel, LS and f values showed significant alterations after TIPS, and these changes were consistent with a reduction in HVPG. Spearman analysis revealed a significant correlation between the parameters (LS and f) and HVPG. The equation was eventually generated for prediction of HVPG. SIGNIFICANCE: The findings show a good correlation between HVPG and the quantitative parameters; thus, imaging-based techniques have potential as non-invasive methods for predicting HVPG.


Assuntos
Veias Hepáticas/fisiopatologia , Hipertensão Portal/diagnóstico por imagem , Hipertensão Portal/fisiopatologia , Imageamento Tridimensional , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/fisiopatologia , Pressão na Veia Porta , Animais , Imagem de Difusão por Ressonância Magnética , Modelos Animais de Doenças , Técnicas de Imagem por Elasticidade , Veias Hepáticas/patologia , Hipertensão Portal/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Masculino , Análise Multivariada , Derivação Portossistêmica Transjugular Intra-Hepática , Análise de Regressão , Reprodutibilidade dos Testes , Suínos , Porco Miniatura
4.
J Prosthet Dent ; 125(1): 89-94, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32059858

RESUMO

STATEMENT OF PROBLEM: The software programs of digital intraoral scanners typically offers the option to cut out areas from 3D casts, to do rescans, and to merge them with the initial scan. However, evidence of whether this procedure has an impact on the accuracy of the scan is lacking. PURPOSE: The purpose of this study was to determine whether "cut out-rescan" procedures change the accuracy of a 3D cast. MATERIAL AND METHODS: A maxillary master cast was digitized with an industrial structured light scanner to obtain a digital reference cast. This master cast was repeatedly scanned by 3 intraoral scanners: TRIOS 3 [TR], Cerec Primescan [PR], and Cerec Omnicam [OM]. The scan data were duplicated, and the posterior area from the right lateral incisor was cut out and rescanned to obtain complete-arch casts containing the rescanned data [TR_rs], [PR_rs], and [OM_rs]. The trueness and precision of the scans were evaluated by superimposing procedures of the relevant data sets. To evaluate statistical differences, either the Mann-Whitney U test or the t test was used (α=.05). RESULTS: The median precision values of the complete-arch scan data was 19 µm for [OM] and [TR], whereas the median for [PR] was 14 µm. In the "cut out-rescanned" data group, the values were 25 µm for [OM_rs], 16 µm for [TR_rs], and 14 µm for [PR_rs]. Statistically significant differences were found among the scanners [OM]/[PR], [OM_rs]/[TR_rs], and [TR_rs]/[PR_rs]. The mean ± standard deviation values of trueness for the complete-arch scan data were 54 ±4 µm for [OM], 42 ±5 µm for [TR], and 30 ±2 µm for [PR]. In the group of the "cut out-rescanned" data, the mean trueness results were 55 ± 6 µm for [OM_rs], 38 ±5 µm for [TR_rs], and 31 ±5 µm for [PR_rs]. Significant differences were found among the complete-arch scan data and the "cut out-rescanned" data of the different scanners, but not between the complete-arch scan data and the "cut out-rescanned" data within one scanning system. CONCLUSIONS: Significant differences were found among the scanners, but "cut out-rescan" procedures did not affect the accuracy within each scanning system.


Assuntos
Técnica de Moldagem Odontológica , Modelos Dentários , Desenho Assistido por Computador , Arco Dental , Imageamento Tridimensional , Maxila/diagnóstico por imagem
5.
J Prosthet Dent ; 125(1): 103-110, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32063385

RESUMO

STATEMENT OF PROBLEM: Reliable studies comparing the accuracy of complete-arch casts from 3D printers are scarce. PURPOSE: The purpose of this in vitro study was to investigate the accuracy of casts printed by using various extrusion- and photopolymerization-based printers. MATERIAL AND METHODS: A master file was sent to 5 printer manufacturers and distributors to print 37 identical casts. This file consisted of a standardized data set of a maxillary cast in standard tessellation language (STL) format comprising 5 reference points for the measurement of 3 distances that served as reference for all measurements: intermolar width (IMW), intercanine width (ICW), and dental arch length (AL). The digital measurement of the master file obtained by using a surveying software program (Convince Premium 2012) was used as the control. Two extrusion-based (M2 and Ultimaker 2+) and 3 photopolymerization-based printers (Form 2, Asiga MAX UV, and myrev140) were compared. The casts were measured by using a multisensory coordinate measuring machine (O-Inspect 422). The values were then compared with those of the master file. The Mann-Whitney U test and Levene tests were used to determine significant differences in the trueness and precision (accuracy) of the measured distances. RESULTS: The deviations from the master file at all 3 distances for the included printers ranged between 12 µm and 240 µm (trueness), with an interquartile range (IQR) between 17 µm and 388 µm (precision). Asiga MAX UV displayed the highest accuracy, considering all the distances, and Ultimaker 2+ demonstrated comparable accuracy for shorter distances (IMW and ICW). Although myrev140 operated with high precision, it displayed high deviations from the master file. Similarly, although Form 2 exhibited high IQR, it did not deviate significantly from the master file in the longest range (AL). M2 performed consistently. CONCLUSIONS: Both extrusion-based and photopolymerization-based printers were accurate. In general, inexpensive printers were no less accurate than more expensive ones.


Assuntos
Modelos Dentários , Impressão Tridimensional , Desenho Assistido por Computador , Técnica de Moldagem Odontológica , Imageamento Tridimensional , Maxila , Software
6.
J Prosthet Dent ; 125(1): 29-33, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32085869

RESUMO

This article describes a method of integrating digital dental casts into cone beam computed tomography (CBCT) scans in virtual implant planning in situations with an excessive number of metal artifacts. This technique requires the use of a prefabricated registration tray to provide a common landmark; is noninvasive, minimally time-consuming, and cost-effective; and requires only a single registration and minimal exposure to radiation.


Assuntos
Implantes Dentários , Modelos Dentários , Artefatos , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional
7.
Ear Nose Throat J ; 100(1): 38-43, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32330070

RESUMO

OBJECTIVE: The objective of this study was to determine the shape of cochlear basal turn through basic cochlear parameters measurement. The secondary aim was to overlay an image of the precurved electrode array on top of the three-dimensional (3D) image of the cochlea to determine which shape of the cochlear basal turn gives optimal electrode-to-modiolus proximity. MATERIALS AND METHODS: Computed tomography (CT) preoperative image-data sets of 117 ears were made available for the measurements of cochlear parameters retrospectively. Three-dimensional slicer was used in the visualization and measurement of cochlear parameters from both 3D and 2D (2-dimensional) images of the inner ear. Cochlear parameters including basal turn diameter (A), width of the basal turn (B), and cochlear height (H) were measured from the appropriate planes. B/A ratio was made to investigate which ratios correspond to round and elliptical shape of the cochlear basal turn. RESULTS: The cochlear size as measured by A value ranged between 7.4 mm and 10 mm. The B value and the cochlear height (H) showed a weak positive linear relation with A value. The ratio between the B and A values anything above or below 0.75 could be an indicator for a more round- or elliptical shaped cochlear basal turn, respectively. One sized/shaped commercially available precurved electrode array would not offer a tight electrode-to-modiolus in the cochlea that has an elliptical shaped basal turn as identified by the B/A ratio of <0.75. CONCLUSION: Accurate measurement of cochlear parameters adds value to the overall understanding of the cochlear geometry before a cochlear implantation procedure. The shape of cochlear basal turn could have clinical implications when comes to electrode-to-modiolus proximity.


Assuntos
Antropometria/métodos , Cóclea/anatomia & histologia , Implante Coclear , Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Cóclea/diagnóstico por imagem , Implantes Cocleares , Feminino , Humanos , Masculino , Estudos Retrospectivos
8.
Clin Oral Investig ; 25(1): 77-85, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32495223

RESUMO

PURPOSE: The purpose of this study was to evaluate the clinical accuracy of the fusion of intra-oral scans in cone-beam computed tomography (CBCT) scans using two commercially available software packages. MATERIALS AND METHODS: Ten dry human skulls were subjected to structured light scanning, CBCT scanning, and intra-oral scanning. Two commercially available software packages were used to perform fusion of the intra-oral scans in the CBCT scan to create an accurate virtual head model: IPS CaseDesigner® and OrthoAnalyzer™. The structured light scanner was used as a gold standard and was superimposed on the virtual head models, created by IPS CaseDesigner® and OrthoAnalyzer™, using an Iterative Closest Point algorithm. Differences between the positions of the intra-oral scans obtained with the software packages were recorded and expressed in six degrees of freedom as well as the inter- and intra-observer intra-class correlation coefficient. RESULTS: The tested software packages, IPS CaseDesigner® and OrthoAnalyzer™, showed a high level of accuracy compared to the gold standard. The accuracy was calculated for all six degrees of freedom. It was noticeable that the accuracy in the cranial/caudal direction was the lowest for IPS CaseDesigner® and OrthoAnalyzer™ in both the maxilla and mandible. The inter- and intra-observer intra-class correlation coefficient showed a high level of agreement between the observers. CLINICAL RELEVANCE: IPS CaseDesigner® and OrthoAnalyzer™ are reliable software packages providing an accurate fusion of the intra-oral scan in the CBCT. Both software packages can be used as an accurate fusion tool of the intra-oral scan in the CBCT which provides an accurate basis for 3D virtual planning.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Humanos , Mandíbula/diagnóstico por imagem , Maxila , Software
9.
Zhonghua Yi Xue Za Zhi ; 100(46): 3674-3679, 2020 Dec 15.
Artigo em Chinês | MEDLINE | ID: mdl-33342143

RESUMO

Objective: To explore the value of speculating etiology of the magnetic resonance imaging (MRI) T1 weighted imaging (T1WI) labyrinthine high signal ratio in patients with unilateral sudden deafness accompanied by vertigo and tinnitus and its relationship with hearing prognosis. Methods: Fifty-two patients with unilateral sudden deafness accompanied by vertigo and tinnitus who were admitted to Beijing Tongren Hospital Affiliated to Capital Medical University from January 2016 to July 2019 were collected, including 27 males and 25 females, aged (47.7±15.1) years. The inner ear MRI data of 52 patients (17 plain scan, 35 enhanced scan) with unilateral sudden deafness were retrospectively analyzed. Two radiologists independently measured the labyrinthine high signal intensity of the affected side and the contralateral normal side on T1WI and enhanced T1WI and calculated the signal ratio (the normal labyrinth signal was subtracted from the affected signal and then divided by the normal signal). The etiology of the enhanced group was judged based on two methods, including whether the abnormal high signal was enhanced or not (unenhancement indicated hemorrhage and enhancement indicated inflammation), and the locations of labyrinthine involvement on enhanced three-dimensional fluid attenuated inversion recovery (3D-FLAIR) (inflammation usually involved the perilymph spaces, while hemorrhage involved the perilymph and endolymph spaces). In the plain group, the locations of labyrinthine involvement on 3D-FLAIR was applied to infer the potential etiology. Results: The two methods presumed that 8 cases might be hemorrhage (22.9%, 8/35) and 27 be inflammation (77.1%, 27/35) in the enhanced group, which had a high consistency, while it was speculated that 7 patients might be hemorrhage (7/17) and 10 patients be inflammation (10/17) in the plain group. The measurement results of the two radiologists were highly consistent within and between the groups [the intraclass correlation coefficient (ICC) values were greater than 0.800]. The area under the receiver operating characteristic (ROC) curve (AUC) of the T1WI high signal ratio in the enhanced group for speculating etiology was 0.949 (P<0.01), when the predictive threshold value was 0.467, with a sensitivity of 96.3% and a specificity of 87.5%. It might be hemorrhage when the ratio was higher than the threshold value, otherwise it was inflammation. The T1WI labyrinthine high signal ratio was higher in the hemorrhage group than that of the inflammation group, and the hearing prognosis was worse (all P<0.05). The T1WI labyrinthine high signal ratio of the unrecovered group was higher than that of the recovered group (P=0.034). Conclusions: The etiology of labyrinthine high signal formation can be inferred by quantitative values combined with the involved sites. The high signal in the labyrinth indicates poor hearing prognosis, the higher the signal intensity, the greater the possibility of hemorrhage and the worse the hearing prognosis.


Assuntos
Orelha Interna , Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Zumbido , Adulto , Orelha Interna/diagnóstico por imagem , Feminino , Perda Auditiva Súbita/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Zumbido/diagnóstico por imagem , Vertigem
10.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 76(12): 1281-1286, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33342947

RESUMO

In radiological examinations of patients, we often take stacked images and three-dimensional (3D) images of human bone radiological images such as X-ray images and CT images. In general, learning of bone structure using specialized anatomy books is currently performed at medical radiological technologist education facilities. In the anatomy education of the medical school, in order to understand the structure of human and the individual bone shapes in detail, a real human bone specimen is used to gain knowledge of skeleton, bone shape, bone name and bone function. But it is actually difficult for a radiological technologist to obtain such learning opportunities. Therefore, we had to depend on two-dimensional information from an anatomical atlas so far. Therefore, as a method to solve this, we devised this stereo-paired bone anatomical chart by stereoscopic photography of a real human bone specimen that is available only in the anatomy laboratory. In classical anatomy textbooks, there are no figures that enable us to view 3D structures of human bones. Our stereo-paired bone anatomical charts make it possible to observe accurate bone structures three-dimensionally. In addition, we saved the data as a PDF file and uploaded to an internet server so that we can freely download and readily observe 3D images of human bones at all times and all places with a tablet or a PC monitor.


Assuntos
Imageamento Tridimensional , Radiação , Compreensão , Humanos , Aprendizagem , Modelos Anatômicos
11.
J Craniomaxillofac Surg ; 48(12): 1119-1125, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33288374

RESUMO

PURPOSE: To evaluate the surgical accuracy of a new Maxillary Bone-Dental-Supported guide (MBDS) for osteotomy and maxillary positioning in orthognathic surgeries. MATERIALS AND METHODS: The customized MBDS were prototyped through CAD-CAM technology (computer-aided design and manufacturing). The planning image (CT0) was superimposed on the computed tomography scan post-treatment (CT1) and the mean of positional differences between them were obtained tridimensionally at the axes: mediolateral (X), anteroposterior (Y) and vertical (Z). RESULTS: Eleven patients were selected according to the inclusion and exclusion criteria. The mediolateral movement showed the best precision, with a greater mean difference of 0.34 mm at the CI point (central incisor) and less than 0.02 mm at the RM point (right molar). In the vertical direction, the largest mean discrepancy found was 0.50 mm and on the y-axis, anteroposterior, was 0.74 mm, as well as two at the CI point. The skeletal SNA point, on the other hand, showed the smallest average discrepancies: 0.10 mm (x-axis), 0.03 mm (y-axis) and 0 mm (z-axis). Overall, 99.24% of the discrepancies found were less than 2 mm. CONCLUSION: Our results suggests that the double support, osseous and dental, present in that new guide, favored the positional stability of the maxilla and promoted better control of its vertical axis. Furthermore, the function of an osteotomy guide increases the predictability and security of the surgical procedure.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Cirurgia Assistida por Computador , Desenho Assistido por Computador , Humanos , Imageamento Tridimensional , Maxila/diagnóstico por imagem , Maxila/cirurgia , Tomografia Computadorizada por Raios X
12.
Compend Contin Educ Dent ; 41(10): 514-519; quiz 520, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33350841

RESUMO

The use of dental implants to restore oral form and function has transformed the dental treatment of both partially and fully edentulous patients. With the advent of cone-beam computed tomography (CBCT) imaging technology in 1998 followed by its establishment at the beginning of the new century as the imaging modality of choice in implant treatment, 2-dimensional treatment planning was abruptly supplemented by the much-cherished third dimension. Additive manufacturing, ie, the fabrication of an object by adding material layer by layer, was pioneered in the early 1980s and has become readily available and relatively affordable over the past few years. Although computer-guided planning of treatment is gaining ground in implant therapy, freehand placement of the fixtures remains the standard of care. Time and cost considerations and lack of proper training throughout the steps involved are factors in why clinicians have been reluctant to adopt computer-guided placement of implants. The purpose of this article is to offer guidance to dental clinicians who favor freehand implant placement to facilitate their transition to computer-guided implantology with the use of static surgical guides.


Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Desenho Assistido por Computador , Computadores , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endo-Óssea , Humanos , Imageamento Tridimensional , Planejamento de Assistência ao Paciente
13.
Nat Commun ; 11(1): 6254, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33288755

RESUMO

The invariant development and transparent body of the nematode Caenorhabditis elegans enables complete delineation of cell lineages throughout development. Despite extensive studies of cell division, cell migration and cell fate differentiation, cell morphology during development has not yet been systematically characterized in any metazoan, including C. elegans. This knowledge gap substantially hampers many studies in both developmental and cell biology. Here we report an automatic pipeline, CShaper, which combines automated segmentation of fluorescently labeled membranes with automated cell lineage tracing. We apply this pipeline to quantify morphological parameters of densely packed cells in 17 developing C. elegans embryos. Consequently, we generate a time-lapse 3D atlas of cell morphology for the C. elegans embryo from the 4- to 350-cell stages, including cell shape, volume, surface area, migration, nucleus position and cell-cell contact with resolved cell identities. We anticipate that CShaper and the morphological atlas will stimulate and enhance further studies in the fields of developmental biology, cell biology and biomechanics.


Assuntos
Caenorhabditis elegans/embriologia , Biologia Computacional/métodos , Aprendizado Profundo , Embrião não Mamífero/citologia , Desenvolvimento Embrionário , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Movimento Celular/fisiologia , Embrião não Mamífero/embriologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos , Morfogênese , Software
14.
J Clin Pediatr Dent ; 44(6): 442-450, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378464

RESUMO

OBJECTIVES: The objectives were to assess the treatment outcomes of unilateral cleft lip and palate after primary surgery on nasolabial soft tissue of children ages 4-5 years old as compared with unaffected children and to establish a nasolabial soft tissue norm within Khon Kaen. STUDY DESIGN: This cross-sectional study consisted of 60 unaffected subjects living in Khon Kaen province and 20 subjects with repaired complete unilateral cleft lip and palate who were treated at Srinagarind Hosipital, Khon Kaen, Thailand. 3D images were taken by a Morpheus 3D Scanner and measured by the Morpheus 3D program. Independent t-tests and paired t-tests were used to analyze the significant differences between subjects with cleft and unaffected subjects. RESULTS: There were statistically significant differences (p<0.05) of nasolabial measurements between affected subjects and unaffected subjects. Unilateral measurements showed decreased nostril height, columella lengths, and nose protrusion from ala base and ala length in the affected group. In addition, bilateral measurements found decreased upper lip protrusion, philtrum length, upper lip height, upper vermillion thickness, and lip angle. CONCLUSION: This study attempted to establish a norm for evaluating the treatment outcome of cleft lip and cleft palate repair at Srinagarind Hospital in relation to unaffected or noncleft individuals. The results suggest that the noncleft side in affected patients is not an optimal surgical guide for cleft repair and the surgeon should correct both sides of lip and nose features according to the norms. A surgical treatment plan should emphasize correcting nostril height, columella length, nose protrusion from ala base, ala length, and upper lip features.


Assuntos
Fenda Labial , Fissura Palatina , Criança , Pré-Escolar , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Estudos Transversais , Humanos , Imageamento Tridimensional , Nariz/cirurgia , Tailândia
15.
BMC Bioinformatics ; 21(Suppl 21): 534, 2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33371884

RESUMO

BACKGROUND: Cryo-EM data generated by electron tomography (ET) contains images for individual protein particles in different orientations and tilted angles. Individual cryo-EM particles can be aligned to reconstruct a 3D density map of a protein structure. However, low contrast and high noise in particle images make it challenging to build 3D density maps at intermediate to high resolution (1-3 Å). To overcome this problem, we propose a fully automated cryo-EM 3D density map reconstruction approach based on deep learning particle picking. RESULTS: A perfect 2D particle mask is fully automatically generated for every single particle. Then, it uses a computer vision image alignment algorithm (image registration) to fully automatically align the particle masks. It calculates the difference of the particle image orientation angles to align the original particle image. Finally, it reconstructs a localized 3D density map between every two single-particle images that have the largest number of corresponding features. The localized 3D density maps are then averaged to reconstruct a final 3D density map. The constructed 3D density map results illustrate the potential to determine the structures of the molecules using a few samples of good particles. Also, using the localized particle samples (with no background) to generate the localized 3D density maps can improve the process of the resolution evaluation in experimental maps of cryo-EM. Tested on two widely used datasets, Auto3DCryoMap is able to reconstruct good 3D density maps using only a few thousand protein particle images, which is much smaller than hundreds of thousands of particles required by the existing methods. CONCLUSIONS: We design a fully automated approach for cryo-EM 3D density maps reconstruction (Auto3DCryoMap). Instead of increasing the signal-to-noise ratio by using 2D class averaging, our approach uses 2D particle masks to produce locally aligned particle images. Auto3DCryoMap is able to accurately align structural particle shapes. Also, it is able to construct a decent 3D density map from only a few thousand aligned particle images while the existing tools require hundreds of thousands of particle images. Finally, by using the pre-processed particle images, Auto3DCryoMap reconstructs a better 3D density map than using the original particle images.


Assuntos
Microscopia Crioeletrônica , Imageamento Tridimensional/métodos , Algoritmos , Automação , Proteínas/química , Razão Sinal-Ruído
16.
J Cardiovasc Magn Reson ; 22(1): 78, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256791

RESUMO

BACKGROUND: Computed tomography angiography (CTA) or contrast-enhanced (CE) cardiovascular magnetic resonance angiography (CMRA) is often obtained in patients with atrial fibrillation undergoing evaluation prior to pulmonary vein (PV) isolation. Drawbacks of CTA include radiation exposure and potential risks from iodinated contrast agent administration. Free-breathing 3D balanced steady-state free precession (bSSFP) Non-contrast CMRA is a potential imaging option, but vascular detail can be suboptimal due to ghost artifacts and blurring that tend to occur with a Cartesian k-space trajectory or, in some cases, inconsistent respiratory gating. We therefore explored the potential utility of both breath-holding and free-breathing non-contrast CMRA, using radial k-space trajectories that are known to be less sensitive to flow and motion artifacts than Cartesian. MAIN BODY: Free-breathing 3D Cartesian and radial stack-of-stars acquisitions were compared in 6 healthy subjects. In addition, 27 patients underwent CTA and non-contrast CMRA for PV mapping. Three radial CMR acquisition strategies were tested: (1) breath-hold (BH) 2D radial bSSFP (BH-2D); (2) breath-hold, multiple thin-slab 3D stack-of-stars bSSFP (BH-SOS); and (3) navigator-gated free-breathing (FB) 3D stack-of-star bSSFP using a spatially non-selective RF excitation (FB-NS-SOS). A non-rigid registration algorithm was used to compensate for variations in breath-hold depth. In healthy subjects, image quality and vessel sharpness using a free-breathing 3D SOS acquisition was significantly better than free-breathing (FB) Cartesian 3D. In patients, diagnostic image quality was obtained using all three radial CMRA techniques, with BH-SOS and FB-NS-SOS outperforming BH-2D. There was overall good correlation for PV maximal diameter between BH-2D and CTA (ICC = 0.87/0.83 for the two readers), excellent correlation between BH-SOS and CTA (ICC = 0.90/0.91), and good to excellent correlation between FB-NS-SOS and CTA (ICC = 0.87/0.94). For PV area, there was overall good correlation between BH-2D and CTA (ICC = 0.79/0.83), good to excellent correlation between BH-SOS and CTA (ICC = 0.88/0.91) and excellent correlation between FB-NS-SOS and CTA (ICC = 0.90/0.95). CNR was significantly higher with BH-SOS (mean = 11.04) by comparison to BH-2D (mean = 6.02; P = 0.007) and FB-NS-SOS (mean = 5.29; P = 0.002). CONCLUSION: Our results suggest that a free-breathing stack-of-stars bSSFP technique is advantageous in providing accurate depiction of PV anatomy and ostial measurements without significant degradation from off-resonance artifacts, and with better image quality than Cartesian 3D. For patients in whom respiratory gating is unsuccessful, a breath-hold thin-slab stack-of-stars technique with retrospective motion correction may be a useful alternative.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Imageamento Tridimensional , Angiografia por Ressonância Magnética , Flebografia , Veias Pulmonares/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Fibrilação Atrial/cirurgia , Técnicas de Imagem de Sincronização Cardíaca , Estudos de Casos e Controles , Angiografia por Tomografia Computadorizada , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Veias Pulmonares/cirurgia , Reprodutibilidade dos Testes
17.
J Cardiovasc Magn Reson ; 22(1): 88, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317570

RESUMO

BACKGROUND: The free-breathing 3D whole-heart T2-prepared Bright-blood and black-blOOd phase SensiTive inversion recovery (BOOST) cardiovascular magnetic resonance (CMR) sequence was recently proposed for simultaneous bright-blood coronary CMR angiography and black-blood late gadolinium enhancement (LGE) imaging. This sequence enables simultaneous visualization of cardiac anatomy, coronary arteries and fibrosis. However, high-resolution (< 1.4 × 1.4 × 1.4 mm3) fully-sampled BOOST requires long acquisition times of ~ 20 min. METHODS: In this work, we propose to extend a highly efficient respiratory-resolved motion-corrected reconstruction framework (XD-ORCCA) to T2-prepared BOOST to enable high-resolution 3D whole-heart coronary CMR angiography and black-blood LGE in a clinically feasible scan time. Twelve healthy subjects were imaged without contrast injection (pre-contrast BOOST) and 10 patients with suspected cardiovascular disease were imaged after contrast injection (post-contrast BOOST). A quantitative analysis software was used to compare accelerated pre-contrast BOOST against the fully-sampled counterpart (vessel sharpness and length of the left and right coronary arteries). Moreover, three cardiologists performed diagnostic image quality scoring for clinical 2D LGE and both bright- and black-blood 3D BOOST imaging using a 4-point scale (1-4, non-diagnostic-fully diagnostic). A two one-sided test of equivalence (TOST) was performed to compare the pre-contrast BOOST images. Nonparametric TOST was performed to compare post-contrast BOOST image quality scores. RESULTS: The proposed method produces images from 3.8 × accelerated non-contrast-enhanced BOOST acquisitions with comparable vessel length and sharpness to those obtained from fully- sampled scans in healthy subjects. Moreover, in terms of visual grading, the 3D BOOST LGE datasets (median 4) and the clinical 2D counterpart (median 3.5) were found to be statistically equivalent (p < 0.05). In addition, bright-blood BOOST images allowed for visualization of the proximal and middle left anterior descending and right coronary sections with high diagnostic quality (mean score > 3.5). CONCLUSIONS: The proposed framework provides high-resolution 3D whole-heart BOOST images from a single free-breathing acquisition in ~ 7 min.


Assuntos
Vasos Coronários/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Imageamento Tridimensional , Imagem por Ressonância Magnética , Miocárdio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Meios de Contraste/administração & dosagem , Feminino , Fibrose , Cardiopatias/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fluxo de Trabalho , Adulto Jovem
18.
Nat Commun ; 11(1): 6151, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262347

RESUMO

Fluorescence microscopy enables spatial and temporal measurements of live cells and cellular communities. However, this potential has not yet been fully realized for investigations of individual cell behaviors and phenotypic changes in dense, three-dimensional (3D) bacterial biofilms. Accurate cell detection and cellular shape measurement in densely packed biofilms are challenging because of the limited resolution and low signal to background ratios (SBRs) in fluorescence microscopy images. In this work, we present Bacterial Cell Morphometry 3D (BCM3D), an image analysis workflow that combines deep learning with mathematical image analysis to accurately segment and classify single bacterial cells in 3D fluorescence images. In BCM3D, deep convolutional neural networks (CNNs) are trained using simulated biofilm images with experimentally realistic SBRs, cell densities, labeling methods, and cell shapes. We systematically evaluate the segmentation accuracy of BCM3D using both simulated and experimental images. Compared to state-of-the-art bacterial cell segmentation approaches, BCM3D consistently achieves higher segmentation accuracy and further enables automated morphometric cell classifications in multi-population biofilms.


Assuntos
Bactérias/citologia , Biofilmes , Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos , Bactérias/química , Bactérias/crescimento & desenvolvimento , Fenômenos Fisiológicos Bacterianos , Aprendizado Profundo , Análise de Célula Única/métodos
19.
Nat Commun ; 11(1): 6090, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33257700

RESUMO

Intracranial aneurysm is a common life-threatening disease. Computed tomography angiography is recommended as the standard diagnosis tool; yet, interpretation can be time-consuming and challenging. We present a specific deep-learning-based model trained on 1,177 digital subtraction angiography verified bone-removal computed tomography angiography cases. The model has good tolerance to image quality and is tested with different manufacturers. Simulated real-world studies are conducted in consecutive internal and external cohorts, in which it achieves an improved patient-level sensitivity and lesion-level sensitivity compared to that of radiologists and expert neurosurgeons. A specific cohort of suspected acute ischemic stroke is employed and it is found that 99.0% predicted-negative cases can be trusted with high confidence, leading to a potential reduction in human workload. A prospective study is warranted to determine whether the algorithm could improve patients' care in comparison to clinicians' assessment.


Assuntos
Angiografia Digital/métodos , Angiografia por Tomografia Computadorizada/métodos , Aprendizado Profundo , Aneurisma Intracraniano/diagnóstico por imagem , Idoso , Algoritmos , Isquemia Encefálica , China , Feminino , Humanos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X/métodos
20.
BMC Bioinformatics ; 21(1): 558, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33276732

RESUMO

BACKGROUND: High resolution 2D whole slide imaging provides rich information about the tissue structure. This information can be a lot richer if these 2D images can be stacked into a 3D tissue volume. A 3D analysis, however, requires accurate reconstruction of the tissue volume from the 2D image stack. This task is not trivial due to the distortions such as tissue tearing, folding and missing at each slide. Performing registration for the whole tissue slices may be adversely affected by distorted tissue regions. Consequently, regional registration is found to be more effective. In this paper, we propose a new approach to an accurate and robust registration of regions of interest for whole slide images. We introduce the idea of multi-scale attention for registration. RESULTS: Using mean similarity index as the metric, the proposed algorithm (mean ± SD [Formula: see text]) followed by a fine registration algorithm ([Formula: see text]) outperformed the state-of-the-art linear whole tissue registration algorithm ([Formula: see text]) and the regional version of this algorithm ([Formula: see text]). The proposed algorithm also outperforms the state-of-the-art nonlinear registration algorithm (original: [Formula: see text], regional: [Formula: see text]) for whole slide images and a recently proposed patch-based registration algorithm (patch size 256: [Formula: see text] , patch size 512: [Formula: see text]) for medical images. CONCLUSION: Using multi-scale attention mechanism leads to a more robust and accurate solution to the problem of regional registration of whole slide images corrupted in some parts by major histological artifacts in the imaged tissue.


Assuntos
Algoritmos , Artefatos , Vasos Sanguíneos/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Vasos Sanguíneos/diagnóstico por imagem , Carcinoma de Células Renais/irrigação sanguínea , Humanos , Imuno-Histoquímica/métodos , Microscopia
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