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1.
Methods Mol Biol ; 2852: 159-170, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39235743

RESUMEN

The functional properties of biofilms are intimately related to their spatial architecture. Structural data are therefore of prime importance to dissect the complex social and survival strategies of biofilms and ultimately to improve their control. Confocal laser scanning microscopy (CLSM) is the most widespread microscopic tool to decipher biofilm structure, enabling noninvasive three-dimensional investigation of their dynamics down to the single-cell scale. The emergence of fully automated high content screening (HCS) systems, associated with large-scale image analysis, has radically amplified the flow of available biofilm structural data. In this contribution, we present a HCS-CLSM protocol used to analyze biofilm four-dimensional structural dynamics at high throughput. Meta-analysis of the quantitative variables extracted from HCS-CLSM will contribute to a better biological understanding of biofilm traits.


Asunto(s)
Biopelículas , Microscopía Confocal , Biopelículas/crecimiento & desarrollo , Microscopía Confocal/métodos , Microbiología de Alimentos/métodos , Imagenología Tridimensional/métodos , Enfermedades Transmitidas por los Alimentos/microbiología , Ensayos Analíticos de Alto Rendimiento/métodos , Procesamiento de Imagen Asistido por Computador/métodos
2.
Methods Mol Biol ; 2854: 177-188, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39192129

RESUMEN

Cryo-electron microscopy is a powerful methodology in structural biology and has been broadly used in high-resolution structure determination for challenging samples, which are not readily available for traditional techniques. In particular, the strength of super macro-complexes and the lack of a need for crystals for cryo-EM make this technique feasible for the structural study of complexes involved in antiviral innate immunity. This chapter presents detailed information and experimental procedures of Cryo-EM for determining the structures of the complexes using STING as an example. The procedures included a sample quality check, high-resolution data acquisition, and image processing for Cryo-EM 3D structure determination.


Asunto(s)
Microscopía por Crioelectrón , Inmunidad Innata , Microscopía por Crioelectrón/métodos , Humanos , Proteínas de la Membrana/inmunología , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos
3.
Methods Mol Biol ; 2856: 263-268, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39283457

RESUMEN

We describe an approach for reconstructing three-dimensional (3D) structures from single-cell Hi-C data. This approach has been inspired by a method of recurrence plots and visualization tools for nonlinear time series data. Some examples are also presented.


Asunto(s)
Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Imagenología Tridimensional/métodos , Humanos , Programas Informáticos , Cromosomas/genética , Algoritmos
4.
J Biomed Opt ; 30(Suppl 1): S13704, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39247519

RESUMEN

Significance: ALA-PpIX and second-window indocyanine green (ICG) have been studied widely for guiding the resection of high-grade gliomas. These agents have different mechanisms of action and uptake characteristics, which can affect their performance as surgical guidance agents. Elucidating these differences in animal models that approach the size and anatomy of the human brain would help guide the use of these agents. Herein, we report on the use of a new pig glioma model and fluorescence cryotomography to evaluate the 3D distributions of both agents throughout the whole brain. Aim: We aim to assess and compare the 3D spatial distributions of ALA-PpIX and second-window ICG in a glioma-bearing pig brain using fluorescence cryotomography. Approach: A glioma was induced in the brain of a transgenic Oncopig via adeno-associated virus delivery of Cre-recombinase plasmids. After tumor induction, the pro-drug 5-ALA and ICG were administered to the animal 3 and 24 h prior to brain harvest, respectively. The harvested brain was imaged using fluorescence cryotomography. The fluorescence distributions of both agents were evaluated in 3D in the whole brain using various spatial distribution and contrast performance metrics. Results: Significant differences in the spatial distributions of both agents were observed. Indocyanine green accumulated within the tumor core, whereas ALA-PpIX appeared more toward the tumor periphery. Both ALA-PpIX and second-window ICG provided elevated tumor-to-background contrast (13 and 23, respectively). Conclusions: This study is the first to demonstrate the use of a new glioma model and large-specimen fluorescence cryotomography to evaluate and compare imaging agent distribution at high resolution in 3D.


Asunto(s)
Neoplasias Encefálicas , Glioma , Imagenología Tridimensional , Verde de Indocianina , Animales , Verde de Indocianina/farmacocinética , Verde de Indocianina/química , Porcinos , Neoplasias Encefálicas/diagnóstico por imagen , Glioma/diagnóstico por imagen , Glioma/patología , Imagenología Tridimensional/métodos , Ácido Aminolevulínico/farmacocinética , Encéfalo/diagnóstico por imagen , Imagen Óptica/métodos , Modelos Animales de Enfermedad
5.
J Indian Soc Pedod Prev Dent ; 42(3): 226-234, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39250207

RESUMEN

BACKGROUND: Contemporary imaging methods and quickly advancing technologies have increased the number of diagnostic tools available in medicine and orthodontics. The current study aimed to determine three-dimensional (3D) space changes that occurred after the extraction of either the maxillary or mandibular primary molars during the mixed dentition period. MATERIALS AND METHODS: The present study was a longitudinal split-mouth study with a study group and a control group. The sample consisted of 20 children aged between 6 and 9 years. Clinical examination, radiological analysis, and 3D digital images of the plaster casts were used sequentially to gather all the data. The dental cast measurements recorded were arch width, arch length, hemi-perimeter, dental space at the extraction site, and angulation of the first permanent molar. The children were recalled for follow-up after 9 months, and all dental cast measurements were repeated using nondestructive 3D computed tomography software. For repeated measurements, the test applied was a paired t-test, and for independent samples, the test was a Student's t-test. RESULTS: A significant decrease in arch width (P = 0.001), arch length (P < 0.001), hemi-perimeter (P < 0.001), D-space (P < 0.001), and E-space (P = 0.001) was observed following extraction. A significant increase in angulation measurements was observed (P = 0.001). CONCLUSION: The study revealed a comparative reduction in mandibular arch width, a reduction in arch length in both the maxilla and the mandible, a reduced hemi-perimeter of dental arches, loss of dental extraction space, and a change in angulation of the erupted first permanent molars following premature loss of the primary molar.


Asunto(s)
Arco Dental , Diente Molar , Diente Primario , Humanos , Arco Dental/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Niño , Diente Primario/diagnóstico por imagen , Femenino , Masculino , Estudios Longitudinales , Tomografía Computarizada por Rayos X/métodos , Imagenología Tridimensional/métodos , Extracción Dental , Mandíbula/diagnóstico por imagen , Dentición Mixta , Maxilar/diagnóstico por imagen
6.
Med Image Anal ; 98: 103311, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39217674

RESUMEN

Optical Coherence Tomography Angiography (OCTA) is a crucial tool in the clinical screening of retinal diseases, allowing for accurate 3D imaging of blood vessels through non-invasive scanning. However, the hardware-based approach for acquiring OCTA images presents challenges due to the need for specialized sensors and expensive devices. In this paper, we introduce a novel method called TransPro, which can translate the readily available 3D Optical Coherence Tomography (OCT) images into 3D OCTA images without requiring any additional hardware modifications. Our TransPro method is primarily driven by two novel ideas that have been overlooked by prior work. The first idea is derived from a critical observation that the OCTA projection map is generated by averaging pixel values from its corresponding B-scans along the Z-axis. Hence, we introduce a hybrid architecture incorporating a 3D adversarial generative network and a novel Heuristic Contextual Guidance (HCG) module, which effectively maintains the consistency of the generated OCTA images between 3D volumes and projection maps. The second idea is to improve the vessel quality in the translated OCTA projection maps. As a result, we propose a novel Vessel Promoted Guidance (VPG) module to enhance the attention of network on retinal vessels. Experimental results on two datasets demonstrate that our TransPro outperforms state-of-the-art approaches, with relative improvements around 11.4% in MAE, 2.7% in PSNR, 2% in SSIM, 40% in VDE, and 9.1% in VDC compared to the baseline method. The code is available at: https://github.com/ustlsh/TransPro.


Asunto(s)
Imagenología Tridimensional , Vasos Retinianos , Tomografía de Coherencia Óptica , Tomografía de Coherencia Óptica/métodos , Humanos , Vasos Retinianos/diagnóstico por imagen , Imagenología Tridimensional/métodos , Heurística , Enfermedades de la Retina/diagnóstico por imagen , Algoritmos , Angiografía/métodos
7.
J Forensic Odontostomatol ; 42(2): 76-86, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39244768

RESUMEN

Although dental patterns are unique, the use of bitemark analysis in personal identification remains controversial. To accurately reproduce and compare three-dimensional models of bitemarks and dental arches, intraoral three-dimensional scans, commonly utilized in clinical dental practice for precise and stable digital impressions, are recommended. This study aims to compare two different techniques for bitemark analysis: a digital method based on the superimposition of digital scans of dental patterns and lesions, and a visual method based on the physical superimposition of impressions and resin casts produced by 3D printing. A sample of 12 volunteers (6 males and 6 females) with a mean age of 26 years was collected as biters. Each subject was asked to bite on custom supports made from semi-rigid water bottles covered with imprintable dental wax. The dental arches and bitemarks were then recorded using an intraoral scanner and dental impressions. Scan superimposition analysis was conducted using CloudCompare software, while resin casts were printed using a 3D printer and physically superimposed on the bitemark impressions by a blind operator, who was not involved in sample collection, bite test execution, prior cast acquisition, or CloudCompare analysis. Both superimposition techniques relied on the selection of 10 corresponding landmarks (on canines and central and lateral incisors of the upper and lower arches) between the dental arches and impressions. The digital superimposition showed an average concordance of 92.5% for the upper arch landmarks and 85% for the lower arch landmarks, with an overall average concordance of 88.8% for both arches combined. In contrast, the visual analysis of resin casts showed an average concordance of 77.5% for the upper arch and 76.7% for the lower arch, with an overall average of 77.1% for both arches combined. In the analysis performed using CloudCompare, the maxillary arch demonstrated the best superimposition, with 4 landmarks (R0, R1, R2, R5) consistently overlapping. The digital analysis outperformed the visual analysis in all four quadrants, particularly in the upper right arch compared to the lower left arch, thereby supporting the integration of digital techniques in forensic applications. Further studies are necessary to validate the digital technique on a larger sample, including subjects with different dental characteristics, bite dynamics, and varying types of supports and substrates.


Asunto(s)
Imagenología Tridimensional , Modelos Dentales , Humanos , Femenino , Masculino , Adulto , Imagenología Tridimensional/métodos , Mordeduras Humanas/diagnóstico por imagen , Impresión Tridimensional , Técnica de Impresión Dental , Arco Dental/diagnóstico por imagen , Arco Dental/anatomía & histología , Programas Informáticos , Procesamiento de Imagen Asistido por Computador/métodos , Odontología Forense/métodos
8.
Chin Clin Oncol ; 13(4): 56, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39238344

RESUMEN

BACKGROUND AND OBJECTIVE: The increasing popularity of three-dimensional (3D) virtual reconstructions of two-dimensional (2D) imaging in urology has led to significant technological advancements, resulting in the creation of highly accurate 3D virtual models (3DVMs) that faithfully replicate individual anatomical details. This technology enhances surgical reality, providing surgeons with hyper-accurate insights into instantaneous subjective surgical anatomy and improving preoperative surgical planning. In the uro-oncologic field, the utility of 3D virtual reconstruction has been demonstrated in nephron-sparing surgery, impacting surgical strategy and postoperative outcomes in prostate cancer (PCa). The aim of this study is to offer a thorough narrative review of the current state and application of 3D reconstructions and augmented reality (AR) in radical prostatectomy (RP). METHODS: A non-systematic literature review was conducted using Medline, PubMed, the Cochrane Database, and Embase to gather information on clinical trials, randomized controlled trials, review articles, and prospective and retrospective studies related to 3DVMs and AR in RP. The search strategy followed the PICOS (Patients, Intervention, Comparison, Outcome, Study design) criteria and was performed in January 2024. KEY CONTENT AND FINDINGS: The adoption of 3D visualization has become widespread, with applications ranging from preoperative planning to intraoperative consultations. The urological community's interest in intraoperative surgical navigation using cognitive, virtual, mixed, and AR during RP is evident in a substantial body of literature, including 16 noteworthy investigations. These studies highlight the varied experiences and benefits of incorporating 3D reconstructions and AR into RP, showcasing improvements in preoperative planning, intraoperative navigation, and real-time decision-making. CONCLUSIONS: The integration of 3DVMs and AR technologies in urological oncology, particularly in the context of RP, has shown promising advancements. These technologies provide crucial support in preoperative planning, intraoperative navigation, and real-time decision-making, significantly improving the visualization of complex anatomical structures helping in the nerve sparing (NS) approach modulation and reducing positive surgical margin (PSM) rate. Despite positive outcomes, challenges such as small patient cohorts, lack of standardized methodologies, and concerns about costs and technology adoption persist.


Asunto(s)
Realidad Aumentada , Imagenología Tridimensional , Prostatectomía , Humanos , Prostatectomía/métodos , Masculino , Imagenología Tridimensional/métodos , Neoplasias de la Próstata/cirugía
9.
Eur J Orthod ; 46(5)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39233488

RESUMEN

BACKGROUND: This study aims to verify Bolton's values for tooth size ratios and to evaluate possible relationships to different occlusal traits using precise digital measurement methods. MATERIALS AND METHODS: Including 1000 consecutively selected patients from three study centres a digital, partially automated model analysis was performed utilizing the software OnyxCeph. The measurements comprised tooth width for calculation of anterior (AR) and overall ratio (OR) as a percentage, arch width, length, perimeter, overjet, overbite, space analysis in millimetre and the assessment of the angle classification. RESULTS: AR and OR were significantly increased compared to Bolton's ratios of 77.2% (AR) and 91.3% (OR). In the gender comparison, male patients showed larger tooth size ratios, especially in the OR. Patients with Angle Class II/1 and II/2 had smaller tooth size ratios than patients with Angle Class III and I. Thus, patients with Angle Class II/1 had the largest tooth diameters in all maxillary teeth and with Angle Class II/2 the smallest tooth sizes in the mandible. The largest tooth widths in the lower jaw were observed in the Angle Class III patient group. Furthermore, a negative correlation from AR/OR to overjet, overbite, and available space in lower jaw as well as a positive correlation to available space in upper jaw was detected. CONCLUSIONS: There is a clear correlation between the tooth size ratios and the present dysgnathia as well as other orthodontically relevant occlusal traits. This prior knowledge about our patients is extremely important to create an individualized treatment plan and enable sufficient occlusion. To achieve a functionally good occlusion with correct overjet and overbite, it is essential that the maxillary and mandibular teeth are proportional in size. Any deviation from the ideal patient in terms of tooth size, number, shape, or arch must be considered in the pre-therapeutic treatment plan in combination with the existing dysgnathia in order to be able to achieve a stable anterior and posterior occlusion with appropriate adjustments to the therapy post-therapeutically.


Asunto(s)
Imagenología Tridimensional , Maloclusión Clase II de Angle , Maloclusión , Odontometría , Diente , Humanos , Masculino , Femenino , Odontometría/métodos , Maloclusión/patología , Maloclusión/terapia , Imagenología Tridimensional/métodos , Diente/anatomía & histología , Factores Sexuales , Maloclusión Clase II de Angle/patología , Maloclusión Clase II de Angle/diagnóstico por imagen , Mandíbula/anatomía & histología , Maloclusión de Angle Clase III/patología , Adolescente , Arco Dental/anatomía & histología , Maloclusión Clase I de Angle/patología , Maloclusión Clase I de Angle/diagnóstico por imagen , Sobremordida/patología , Maxilar/anatomía & histología , Adulto Joven , Adulto , Modelos Dentales , Programas Informáticos , Oclusión Dental
10.
PLoS One ; 19(9): e0309381, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39241082

RESUMEN

Determination of the cracking behavior during crack propagation helps to better understand damage and fracture processes in brittle rocks. The paper studies the cracking behavior of rocks on three scales: macro-deformation (or macro-cracking), internal micro-fracture, and surface crack coalescence. Under uniaxial compression, the cracking behavior of two types of sandstone specimens having single flaws was experimentally and systematically investigated. Acoustic emission (AE) and three-dimensional digital image correlation (3D-DIC) techniques were utilized to continuously monitor the acoustic shock signals generated by micro-fracture events inside the specimen and the specimen surface cracking process. The experimental results show that at the crack initiation stage, many micro-tensile fractures within the rock are initiated and coalesced, and small strain localized zones (SLZs) appear on the specimen surface. In the crack propagation stage, micro-fractures coalesce into macro-fractures that propagate in tensile mode to form surface cracks, which finally break in tension or slide against each other in shear mode. The formation of SLZs is related to the dip angle of pre-existing flaws, which determines the direction and mode of crack propagation. In conclusion, the strong acoustic-optical evidence accompanying different cracking behaviors is discussed in detail. From both acoustic and optical perspectives, it reveals and explains how flaws and material properties affect the strength and cracking mechanisms of brittle rocks. The study aids comprehension of the potential relation between internal micro-fracture and surface cracking in the process of engineering rock mass failure.


Asunto(s)
Acústica , Imagenología Tridimensional , Imagenología Tridimensional/métodos , Resistencia a la Tracción , Estrés Mecánico , Arena
11.
Nat Commun ; 15(1): 7806, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242563

RESUMEN

Three-dimensional Spatial Transcriptomics has revolutionized our understanding of tissue regionalization, organogenesis, and development. However, existing approaches overlook either spatial information or experiment-induced distortions, leading to significant discrepancies between reconstruction results and in vivo cell locations, causing unreliable downstream analysis. To address these challenges, we propose ST-GEARS (Spatial Transcriptomics GEospatial profile recovery system through AnchoRS). By employing innovative Distributive Constraints into the Optimization scheme, ST-GEARS retrieves anchors with exceeding precision that connect closest spots across sections in vivo. Guided by the anchors, it first rigidly aligns sections, next solves and denoises Elastic Fields to counteract distortions. Through mathematically proved Bi-sectional Fields Application, it eventually recovers the original spatial profile. Studying ST-GEARS across number of sections, sectional distances and sequencing platforms, we observed its outstanding performance on tissue, cell, and gene levels. ST-GEARS provides precise and well-explainable 'gears' between in vivo situations and in vitro analysis, powerfully fueling potential of biological discoveries.


Asunto(s)
Transcriptoma , Animales , Imagenología Tridimensional/métodos , Ratones , Perfilación de la Expresión Génica/métodos , Humanos , Algoritmos
12.
BMC Med Imaging ; 24(1): 233, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243001

RESUMEN

High-Intensity Focused Ultrasound (HIFU) ablation represents a rapidly advancing non-invasive treatment modality that has achieved considerable success in addressing uterine fibroids, which constitute over 50% of benign gynecological tumors. Preoperative Magnetic Resonance Imaging (MRI) plays a pivotal role in the planning and guidance of HIFU surgery for uterine fibroids, wherein the segmentation of tumors holds critical significance. The segmentation process was previously manually executed by medical experts, entailing a time-consuming and labor-intensive procedure heavily reliant on clinical expertise. This study introduced deep learning-based nnU-Net models, offering a cost-effective approach for their application in the segmentation of uterine fibroids utilizing preoperative MRI images. Furthermore, 3D reconstruction of the segmented targets was implemented to guide HIFU surgery. The evaluation of segmentation and 3D reconstruction performance was conducted with a focus on enhancing the safety and effectiveness of HIFU surgery. Results demonstrated the nnU-Net's commendable performance in the segmentation of uterine fibroids and their surrounding organs. Specifically, 3D nnU-Net achieved Dice Similarity Coefficients (DSC) of 92.55% for the uterus, 95.63% for fibroids, 92.69% for the spine, 89.63% for the endometrium, 97.75% for the bladder, and 90.45% for the urethral orifice. Compared to other state-of-the-art methods such as HIFUNet, U-Net, R2U-Net, ConvUNeXt and 2D nnU-Net, 3D nnU-Net demonstrated significantly higher DSC values, highlighting its superior accuracy and robustness. In conclusion, the efficacy of the 3D nnU-Net model for automated segmentation of the uterus and its surrounding organs was robustly validated. When integrated with intra-operative ultrasound imaging, this segmentation method and 3D reconstruction hold substantial potential to enhance the safety and efficiency of HIFU surgery in the clinical treatment of uterine fibroids.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación , Imagenología Tridimensional , Leiomioma , Imagen por Resonancia Magnética , Neoplasias Uterinas , Humanos , Leiomioma/diagnóstico por imagen , Leiomioma/cirugía , Femenino , Imagenología Tridimensional/métodos , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias Uterinas/diagnóstico por imagen , Neoplasias Uterinas/cirugía , Aprendizaje Profundo , Cirugía Asistida por Computador/métodos
13.
Clin Oral Investig ; 28(10): 516, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39243295

RESUMEN

OBJECTIVES: This study analyzed the human maxilla to support the development of mean-value-based cutting guide systems for maxillary reconstruction, bridging the gap between freehand techniques and virtual surgical planning (VSP). MATERIALS AND METHODS: This retrospective cohort study used routine CT scans. DICOM data enabled 3D modelling and the maxilla was divided into four regions: paranasal (R1), facial maxillary sinus wall (R2), zygomatic bone (R3) and alveolar process (R4). Surface comparisons were made with a reference skull. Statistical analyses assessed anatomical variations, focusing on mean distance (Dmean), area of valid distance (AVD), integrated distance (ID) and integrated absolute distance (IAD). The study addressed hemimaxillectomy defects for two-segmental reconstructions using seven defined bilateral points to determine segmental distances and angles. RESULTS: Data from 50 patients showed R2 as the most homogeneous and R4 as the most heterogeneous region. Significant age and gender differences were found in R3 and R4, with younger patients and females having more outliers. Cluster analysis indicated that males had R1 and R3 positioned anterior to the reference skull. The mean angle for segmental reconstruction was 131.24° ± 1.29°, with anterior segment length of 30.71 ± 0.57 mm and posterior length of 28.15 ± 0.86 mm. CONCLUSIONS: Anatomical analysis supported the development of semistandardized segmental resection approaches. Although gender and anatomical differences were noted, they did not significantly impact the feasibility of mean-value-based cutting-guide systems. CLINICAL RELEVANCE: This study provides essential anatomical data for creating cost-effective and efficient reconstruction options for maxillary defects, potentially improving surgical outcomes and expanding reconstructive possibilities beyond current techniques.


Asunto(s)
Imagenología Tridimensional , Maxilar , Procedimientos de Cirugía Plástica , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Estudios Retrospectivos , Maxilar/cirugía , Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Imagenología Tridimensional/métodos , Adulto , Anciano , Procedimientos de Cirugía Plástica/métodos , Peroné/trasplante , Trasplante Óseo/métodos , Planificación de Atención al Paciente
14.
Med Image Anal ; 98: 103295, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39217673

RESUMEN

PURPOSE: Vision Transformers recently achieved a competitive performance compared with CNNs due to their excellent capability of learning global representation. However, there are two major challenges when applying them to 3D image segmentation: i) Because of the large size of 3D medical images, comprehensive global information is hard to capture due to the enormous computational costs. ii) Insufficient local inductive bias in Transformers affects the ability to segment detailed features such as ambiguous and subtly defined boundaries. Hence, to apply the Vision Transformer mechanism in the medical image segmentation field, the above challenges need to be overcome adequately. METHODS: We propose a hybrid paradigm, called Variable-Shape Mixed Transformer (VSmTrans), that integrates self-attention and convolution and can enjoy the benefits of free learning of both complex relationships from the self-attention mechanism and the local prior knowledge from convolution. Specifically, we designed a Variable-Shape self-attention mechanism, which can rapidly expand the receptive field without extra computing cost and achieve a good trade-off between global awareness and local details. In addition, the parallel convolution paradigm introduces strong local inductive bias to facilitate the ability to excavate details. Meanwhile, a pair of learnable parameters can automatically adjust the importance of the above two paradigms. Extensive experiments were conducted on two public medical image datasets with different modalities: the AMOS CT dataset and the BraTS2021 MRI dataset. RESULTS: Our method achieves the best average Dice scores of 88.3 % and 89.7 % on these datasets, which are superior to the previous state-of-the-art Swin Transformer-based and CNN-based architectures. A series of ablation experiments were also conducted to verify the efficiency of the proposed hybrid mechanism and the components and explore the effectiveness of those key parameters in VSmTrans. CONCLUSIONS: The proposed hybrid Transformer-based backbone network for 3D medical image segmentation can tightly integrate self-attention and convolution to exploit the advantages of these two paradigms. The experimental results demonstrate our method's superiority compared to other state-of-the-art methods. The hybrid paradigm seems to be most appropriate to the medical image segmentation field. The ablation experiments also demonstrate that the proposed hybrid mechanism can effectively balance large receptive fields with local inductive biases, resulting in highly accurate segmentation results, especially in capturing details. Our code is available at https://github.com/qingze-bai/VSmTrans.


Asunto(s)
Imagenología Tridimensional , Humanos , Imagenología Tridimensional/métodos , Algoritmos , Redes Neurales de la Computación , Tomografía Computarizada por Rayos X , Imagen por Resonancia Magnética/métodos
15.
Skin Res Technol ; 30(9): e13643, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39221700

RESUMEN

BACKGROUND: Quantitative biomarkers of facial skin aging were investigated in 109 healthy Asian female volunteers, aged 20 to 70 years. MATERIALS AND METHODS: In vivo 3D Line-field Confocal Optical Coherence Tomography (LC-OCT) imaging, enhanced by Artificial Intelligence (AI)-based quantification algorithms, was utilized to compute various metrics, including stratum corneum thickness (SC), viable epidermal (VE) thickness, and Dermal-Epidermal Junction (DEJ) undulation along with cellular metrics for the temple, cheekbone, and mandible. RESULTS: Comparison with data from a cohort of healthy Caucasian volunteers revealed similarities in the variations of stratum corneum and viable epidermis layers, as well as cellular shape and size with age in both ethnic groups. However, specific findings emerged, such as larger, more heterogeneous nuclei in both layers, demonstrated by an increase in nuclei volume and their standard deviation, and increased network atypia, all showing significant age-related variations. Caucasian females exhibited a flatter and more homogeneous epidermis, evidenced by a decreased standard deviation of the number of layers, and a less dense cellular network with fewer cells per layer, indicated by a decrease in cell surface density. CONCLUSION: Ethnicity-wise comparisons highlighted distinct biological features specific to each population. Asian individuals showed significantly higher DEJ undulation, higher compactness, and lower cell network atypia compared to their Caucasian counterparts across age groups. Differences in stratum corneum and viable epidermal thickness on the cheekbone were also significant. LC-OCT 3D imaging provides valuable insights into the aging process in different populations and underscores inherent biological differences between Caucasian and Asian female volunteers.


Asunto(s)
Pueblo Asiatico , Cara , Imagenología Tridimensional , Envejecimiento de la Piel , Tomografía de Coherencia Óptica , Población Blanca , Humanos , Femenino , Envejecimiento de la Piel/fisiología , Envejecimiento de la Piel/etnología , Adulto , Tomografía de Coherencia Óptica/métodos , Persona de Mediana Edad , Cara/diagnóstico por imagen , Cara/anatomía & histología , Imagenología Tridimensional/métodos , Anciano , Adulto Joven , Epidermis/diagnóstico por imagen , Voluntarios Sanos
16.
Acta Neurochir (Wien) ; 166(1): 359, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227482

RESUMEN

PURPOSE: Recent innovations in radiological imaging have enabled the detection of micro-remnant niduses of arteriovenous malformations (AVMs) after gamma knife radiosurgery (GKS), which have not been previously perceptible. Herein, we focus on the difficulty of evaluating micro-remnant AVMs after GKS that are hardly perceptible on conventional examinations and propose integrating follow-up three-dimensional rotational angiography (3D-RA) in the previous gamma plan as a solution. METHODS: We retrospectively searched NTT Medical Center Tokyo hospital database for patients with AVMs who underwent both two-dimensional digital subtraction angiography (2D-DSA) and 3D-RA as follow-up for GKS from February 2021 to January 2024. Patients with suspected nidus occlusion on the latest non-contrast-enhanced magnetic resonance angiography (NC-MRA) were included, and contrast-enhanced magnetic resonance angiography (CE-MRA), 2D-DSA, and 3D-RA were evaluated. RESULTS: Twelve patients with 13 AVM sites were defined as having complete nidus occlusion on upfront NC-MRA. On 2D-DSA, seven AVM sites showed the presence of slight remaining AVMs based on the detection of remnant drainage veins, however the nidus was not detected in three cases. Nevertheless, 3D-RA detected micro-remnant niduses in all seven AVM sites, and four patients underwent re-GKS. Nine patients with ten AVM sites also underwent CE-MRA, and six AVM sites were diagnosed with radiation-induced parenchymal injury. CONCLUSION: Importing the 3D-RA image into the treatment planning has the potential to be more helpful than NC-MRA or CE-MRA to detect micro-remnant AVMs and evaluate the true remnant volume, and may contribute to a more detailed treatment planning, thereby improving the results of GKS retreatment.


Asunto(s)
Angiografía de Substracción Digital , Imagenología Tridimensional , Malformaciones Arteriovenosas Intracraneales , Angiografía por Resonancia Magnética , Radiocirugia , Humanos , Radiocirugia/métodos , Masculino , Malformaciones Arteriovenosas Intracraneales/cirugía , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Femenino , Adulto , Persona de Mediana Edad , Estudios Retrospectivos , Imagenología Tridimensional/métodos , Angiografía de Substracción Digital/métodos , Anciano , Angiografía por Resonancia Magnética/métodos , Angiografía Cerebral/métodos , Adulto Joven
18.
Oper Neurosurg (Hagerstown) ; 27(4): 431-439, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39283098

RESUMEN

BACKGROUND AND OBJECTIVES: Frameless deep brain stimulation (DBS) offers advantages in terms of patient comfort and reduced operative time. However, the need for bony fiducial markers for localization remains a drawback due to the time-consuming and uncomfortable procedure. An alternative localization method involves the direct tracking of an intraoperative 3-dimensional scanner. This study aims to assess the accuracy of the NexFrame frameless DBS system in conjunction with the O-Arm (Medtronic Inc.), both with and without fiducial markers. METHODS: The locations of 100 DBS leads were determined, with 50 cases using fiducial-free localization and 50 involving fiducial markers. The coordinates were compared with the expected intraoperative targets. Absolute errors in the X, Y, and Z coordinates (ΔX, ΔY, and ΔZ) were calculated, along with the vector error (Euclidean) (vector error ). RESULTS: The vector error averaged 1.61 ± 0.49 mm (right) and 1.52 ± 0.60 mm (left) for the group without fiducial bone markers and 1.66 ± 0.69 (right) and 1.44 ± 0.65 mm (left) for the other cohort (P = .76 right; P = .67 left). Absolute errors in the X, Y, and Z coordinates for the fiducial-free group were 0.88 ± 0.55, 0.79 ± 0.45, and 0.79 ± 0.57 mm (right) and 0.72 ± 0.37, 0.78 ± 0.56, and 0.77 ± 0.71 mm (left). For the group with fiducial markers, these errors were 0.87 ± 0.72, 0.92 ± 0.39, and 0.86 ± 0.50 mm (right) and 0.75 ± 0.33, 0.80 ± 0.51, and 0.73 ± 0.64 mm (left) with no statistically significant difference. CONCLUSION: Our analysis of the accuracy of NexFrame DBS, both with and without fiducial markers, using an intraoperative navigable cone-beam computed tomography, demonstrates that both techniques provide sufficient and equivalent 3-dimensional accuracy.


Asunto(s)
Estimulación Encefálica Profunda , Marcadores Fiduciales , Neuronavegación , Humanos , Estimulación Encefálica Profunda/instrumentación , Estimulación Encefálica Profunda/métodos , Masculino , Femenino , Neuronavegación/métodos , Neuronavegación/instrumentación , Persona de Mediana Edad , Anciano , Imagenología Tridimensional/métodos , Adulto , Electrodos Implantados
19.
JAMA Netw Open ; 7(9): e2434143, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39283633

RESUMEN

Importance: Planning complex operations such as robotic-assisted laparoscopic radical prostatectomy (RALP) requires surgeons to review 2-dimensional magnetic resonance imaging (MRI) scans to understand 3-dimensional (3D) patient anatomy. Three-dimensional digital models for planning RALP may allow better understanding of patient anatomy and may lead to better patient outcomes, although data are currently limited. Objective: To determine surgical outcomes after RALP when surgeons reviewed 3D digital models during operative planning. Design, Setting, and Participants: This study was a planned secondary analysis of a multicenter, single-blind, randomized clinical trial conducted at 6 large teaching hospitals in the US. The study was conducted between January 1, 2019, and December 31, 2022, and included patients undergoing RALP. Patients were assessed and recruited at the time of surgical consultation. Final data analysis was conducted between August and December 2023. Intervention: Patients were randomized to either a control group undergoing usual preoperative planning with prostate biopsy results and multiparametric MRI only or to an intervention group in which imaging and biopsy results were supplemented with a 3D digital model. This model was viewed on the surgeon's mobile phone in 3D format and picture-in-picture on the robotic console screen. Main Outcomes and Measures: The primary outcome measure for the overall study was oncologic outcomes after RALP, measured as prostate-specific antigen (PSA) detectability. Secondary outcomes were sexual function and urinary function, measured with Sexual Health Inventory for Men (SHIM) scores and rates of urinary incontinence, respectively, as well as use of salvage or adjuvant radiation therapy (RT) or androgen deprivation therapy (ADT). Trifecta outcomes were defined as undetectable PSA without RT or ADT, SHIM score categorically the same or greater than preoperatively, and complete continence. Univariate analysis was performed to compare outcomes between groups. Results: This trial included 92 patients undergoing RALP (51 in the control group and 41 in the intervention group). Their mean (SD) age was 62 (7.4) years; 10 patients (10.9%) were Black and 67 (72.8%) were White. At 18 months postsurgery, the intervention group had lower rates of biochemical recurrence (PSA level >0.1 ng/mL, 0 vs 7 [17.9%]; absolute difference, 17.9% [95% CI, 1.8% to 31.8%]; P = .01) and were significantly less likely to undergo adjuvant or salvage RT (1 [3.1%] vs 12 [31.6%]; absolute difference, 28.5% [95% CI, 10.1% to 46.7%]; P = .002) compared with the control group. Sexual function at 18 months postsurgery was significantly better in the intervention group (mean [SD] SHIM score, 16.8 [8.7] vs 9.8 [7.7]; absolute difference, 7.0 [95% CI, 2.6 to 11.4]; P = .002) and urinary function was unchanged (total continence, 22 [78.6%] vs 29 [80.6%]; absolute difference, 2.0% [95% CI, -17.9% to 21.9%]; P = .84) compared with the control group. Trifecta outcomes were achieved for 12 (48.0%) patients in the intervention group and 3 patients (10.0%) in the control group (absolute difference, 38.0% [95% CI, 14.4% to 61.6%]; P = .002). Conclusions and Relevance: In this secondary analysis of a randomized clinical trial, patients whose surgical planning of RALP involved 3D digital models had better oncologic and functional outcomes. Further work should assess the effect of 3D models in a broader set of patients, physicians, and hospital settings. Trial Registration: ClinicalTrials.gov Identifier: NCT03943368.


Asunto(s)
Prostatectomía , Neoplasias de la Próstata , Procedimientos Quirúrgicos Robotizados , Humanos , Masculino , Prostatectomía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Persona de Mediana Edad , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Anciano , Imagenología Tridimensional/métodos , Método Simple Ciego , Resultado del Tratamiento , Próstata/cirugía , Próstata/patología
20.
BMC Oral Health ; 24(1): 1064, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261793

RESUMEN

OBJECTIVE: This study aimed to develop a deep learning model to predict skeletal malocclusions with an acceptable level of accuracy using airway and cephalometric landmark values obtained from analyzing different CBCT images. BACKGROUND: In orthodontics, multitudinous studies have reported the correlation between orthodontic treatment and changes in the anatomy as well as the functioning of the airway. Typically, the values obtained from various measurements of cephalometric landmarks are used to determine skeletal class based on the interpretation an orthodontist experiences, which sometimes may not be accurate. METHODS: Samples of skeletal anatomical data were retrospectively obtained and recorded in Digital Imaging and Communications in Medicine (DICOM) file format. The DICOM files were used to reconstruct 3D models using 3DSlicer (slicer.org) by thresholding airway regions to build up 3D polygon models of airway regions for each sample. The 3D models were measured for different landmarks that included measurements across the nasopharynx, the oropharynx, and the hypopharynx. Male and female subjects were combined as one data set to develop supervised learning models. These measurements were utilized to build 7 artificial intelligence-based supervised learning models. RESULTS: The supervised learning model with the best accuracy was Random Forest, with a value of 0.74. All the other models were lower in terms of their accuracy. The recall scores for Class I, II, and III malocclusions were 0.71, 0.69, and 0.77, respectively, which represented the total number of actual positive cases predicted correctly, making the sensitivity of the model high. CONCLUSION: In this study, it is observed that the Random Forest model was the most accurate model for predicting the skeletal malocclusion based on various airway and cephalometric landmarks.


Asunto(s)
Puntos Anatómicos de Referencia , Cefalometría , Tomografía Computarizada de Haz Cónico , Maloclusión , Humanos , Cefalometría/métodos , Masculino , Puntos Anatómicos de Referencia/diagnóstico por imagen , Femenino , Tomografía Computarizada de Haz Cónico/métodos , Estudios Retrospectivos , Maloclusión/clasificación , Maloclusión/diagnóstico por imagen , Maloclusión/patología , Imagenología Tridimensional/métodos , Orofaringe/diagnóstico por imagen , Orofaringe/patología , Orofaringe/anatomía & histología , Aprendizaje Profundo , Adolescente , Nasofaringe/diagnóstico por imagen , Nasofaringe/patología , Nasofaringe/anatomía & histología , Hipofaringe/diagnóstico por imagen , Hipofaringe/patología
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