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1.
Orthop Traumatol Surg Res ; : 103922, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936697

RESUMO

INTRODUCTION: The modified Stoppa approach is gradually becoming the gold standard in pelvic ring and acetabulum surgery. One of the potential intraoperative complications is vascular injury. The aim of this study was to identify the level of division of common iliac vessels with respect to a bone landmark, their inter-individual variability and their correlation with morphological criteria. MATERIAL AND METHODS: This was a single-center continuous retrospective study of patients who had preoperative CT angiography for pelvic fracture between February 2017 and May 2018. The level of arterial and venous division and the angle of vein division were measured bilaterally for each patient from the most antero-inferior part of the sacroiliac joint on multiplanar reconstruction and standardized analysis. Relationships with morphological data (age, gender, BMI, height), anterior column fracture and deep venous thrombosis were analyzed. RESULTS: The right arterial division level was 50±16mm (-2.35; 96) from the landmark and the left arterial division level 44±14mm (0; 80). The right venous division level was 30±12mm (-9; 75) and the left venous division level 30±13mm (-5; 66). The right venous bifurcation angle was 65±18° (22; 119) and the left venous bifurcation angle 68±17° (18; 117). The arterial division level was significantly higher on the right side (p=0.007). There were no significant correlations with morphological data. CONCLUSION: The great inter-individual variability of iliac vessels should prompt analysis of their morphology on routine imaging when planning pelvic surgery using the modified Stoppa approach, in order to anticipate the risk of bleeding. LEVEL OF EVIDENCE: IV; cases series.

2.
J Stomatol Oral Maxillofac Surg ; : 101856, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38565423

RESUMO

OBJECTIVE: Developing the skills of a proficient surgeon with a deep understanding of force requires extensive training and repetitive practice. Traditionally, dental students and surgical trainees observed and participated in procedures using models, animals, or cadavers under expert supervision before performing the procedures independently. To address these challenges, interactive simulators with visuo-haptic features have been introduced in surgical training, providing visual and tactile feedback that replicates the sense of touch through applied forces, vibrations, or motions. STUDY DESIGN: Two independent reviewers employed a specific search strategy to explore online databases such as PubMed, Scopus, and Web of Science (WoS). This strategy included keywords such as "haptic device," "education," "oral surgery," "surgery," and "maxillofacial surgery." All types of studies related to maxillofacial surgery, except for case reports, reviews, and eBooks, were considered for inclusion. RESULTS: A total of 22 articles meeting the screening criteria were identified. The use of haptic devices for training dental students in oral surgery, anesthesia, as well as oral and maxillofacial trainees and surgeons in various surgical procedures, was evaluated. CONCLUSION: Incorporating tactile devices into the training of residents and maxillofacial surgeons offers numerous advantages, including improved technical skills and enhanced patient safety.

3.
J Craniomaxillofac Surg ; 52(6): 722-726, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38580557

RESUMO

The contemporary significance of celebrities' facial aesthetics underscores their heightened importance in shaping attractiveness standards. This retrospective study aimed to investigate the impact of patterns on aesthetic canons in the profile views of female celebrities, using artificial intelligence. The study sought to compare different races and propose standards for attractive faces. In this retrospective cohort study, a Python-based algorithm was used to analyze frontal patterns and evaluate their influence on aesthetic norms in publicly accessible images of female global celebrities. Ten ideal angular or proportional measures were gathered from the literature, and were trained to serve as a benchmark for the analysis of facial attractiveness. Demographic characteristics were described statistically. A one-way ANOVA test was employed to assess data distribution. Differences in means between groups were evaluated using nonparametric independent-sample tests, with statistical significance set at < 0.05. The study involved facial analyses for 115 female celebrities. It revealed variations in facial features among races. The mean golden ratio differed, with African and Asian individuals showing lower ratios. Symmetry varied, with Latin and Caucasian faces considered the most symmetrical. The zygomatic-to-mandibular width ratio was similar across races, with a ratio close to 80% being associated with more attractive faces. Differences in nose-to-mouth ratio, lips, alar base width, and chin angle were noted among race groups. The study concluded that, regardless of race, an attractive female face is characterized by specific ratios and angles. Facial symmetry, though desirable, is not strictly necessary. Irrespective of race background, an appealing female face is characterized by a zygomatic-to-mandibular width ratio nearing 80%, a mid-facial third that is slightly larger than the lower third, and a distinctive chin angle of approximately 138°, contributing to a trapezoidal facial shape. The findings contribute valuable insights into attractiveness standards and the impact of frontal patterns on aesthetic canons in female celebrities.


Assuntos
Inteligência Artificial , Beleza , Face , Humanos , Feminino , Estudos Retrospectivos , Face/anatomia & histologia , Adulto , Pessoas Famosas , Estética , Adulto Jovem
4.
J Craniomaxillofac Surg ; 52(5): 652-658, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582679

RESUMO

The present paper provides a historical context for chaos theory, originating in the 1960s with Edward Norton Lorenz's efforts to predict weather patterns. It introduces chaos theory, fractal geometry, nonlinear dynamics, and the butterfly effect, highlighting their exploration of complex systems. The authors aim to bridge the gap between chaos theory and oral and maxillofacial surgery (OMFS) through a literature review, exploring its applications and emphasizing the prevention of minor deviations in OMFS to avoid significant consequences. A comprehensive literature review was conducted on PubMed, Web of Science, and Google Scholar databases. The selection process adhered to the PRISMA-ScR guidelines and Leiden Manifesto principles. Articles focusing on chaos theory principles in health sciences, published in the last two decades, were included. The review encompassed 37 articles after screening 386 works. It revealed applications in outcome variation, surgical planning, simulations, decision-making, and emerging technologies. Potential applications include predicting infections, malignancies, dental fractures, and improving decision-making through disease prediction systems. Emerging technologies, despite criticisms, indicate advancements in AI integration, contributing to enhanced diagnostic accuracy and personalized treatment strategies. Chaos theory, a distinct scientific framework, holds potential to revolutionize OMFS. Its integration with advanced techniques promises personalized, less traumatic surgeries and improved patient care. The interdisciplinary synergy of chaos theory and emerging technologies presents a future in which OMFS practices become more efficient, less traumatic, and achieve a level of precision never seen before.


Assuntos
Dinâmica não Linear , Cirurgia Bucal , Humanos , Procedimentos Cirúrgicos Bucais/métodos , Fractais
5.
Artigo em Inglês | MEDLINE | ID: mdl-38677326

RESUMO

PURPOSE: Anticipating trends and pursuing innovative ideas are imperative for the advancement of science. The objective of this study was to conduct a bibliometric analysis of 3-dimensional virtual simulation in orthognathic surgery, explore its implications for clinical practice, and identify future publication trends through digital tools. METHODS: This study employed a retrospective bibliometric analysis using data obtained from the Web of Science database. The search strategy focused on articles related to orthognathic surgery and virtual simulation techniques. RStudio and bibliometrix tools were used to data mining. The independent variables retrieved from digital analysis were the emerging themes related to virtual planning in orthognathic surgery. The trends that we identified were facial esthetics, digital workflow, personalized treatments, and complex cases. The primary outcome variable was the number of publications dedicated to virtual simulation in orthognathic surgery, along with secondary outcomes such as citation rates, language of publication, country of origin, institutional affiliations, and emerging research themes. Covariates included variables related to publication characteristics, author affiliations, and geographic distribution of publications. Publication analyses over time involved descriptive statistics, regression analysis, Pearson correlation tests, and graphical representation techniques. Statistical significance was set at a 95% confidence interval (P value < .05). RESULTS: A comprehensive analysis of 987 articles reveals the impact of included authors, with a mean h-index of 62 (SD = 18.4). The analysis further illuminates a discernible upward trend in publications on this subject, showcasing a linear pattern with a notable R2 value of 0.88 (P = .021). English remains the predominant language of publication, accounting for 97.97% of articles, while contributions hailed from a diverse spectrum of 56 countries. Interestingly, a moderate correlation emerges between publication numbers and gross domestic product per capita (r = 0.30, P = .044) and total area (r = 0.30, P = .032), whereas a more substantial correlation is evident with total population (r = 0.61, P = .034). Notably, the most cited article amassed 254 citations. Furthermore, a Pearson correlation coefficient of 0.97 underscores the correlation between citation density and the year of publication. CONCLUSION: The bibliometric indicators provided insights for evaluating research productivity and the quality of research output. Emerging themes included facial esthetics, 3-dimensional printing, and the utilization of custom-made templates and implants. This study holds relevance for maxillofacial surgeons, academics, and researchers alike.

6.
J Stomatol Oral Maxillofac Surg ; 125(3S): 101826, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38484842

RESUMO

OBJECTIVES: Altmetrics is one of the fields of bibliometrics that seeks to assess the impact and interest of a given subject through Internet users. The aim of this study is to make an altmetric analysis of the orthognathic surgery literature. METHODS: A literature search was conducted using Dimensions app up to December 2023. A list of the 100 most mentioned articles on the topic was compiled. A Google Trends search was performed with same strategy to visualize important data regarding internet search. Charts and tables were created using Microsoft Excel and VOSviewer software to allow bibliometric visualization. RESULTS: There was a very poor correlation between the number of mentions and the number of citations (r = 0.0202). Most articles discussed on technical innovations associated to orthognathic surgery, majority related to virtual planning (n = 26). Other topics considered interesting to internet readers were complications (n = 18), surgical technique (n = 14), and psychological aspects/quality of life (n = 13). CONCLUSION: Online interest in orthognathic surgery closely aligns with the level of academic interest but is also influenced by factors such as location and economic status. The internet is a powerful tool for disseminating scientific research to a broad audience, making it more accessible and engaging than traditional academic channels.


Assuntos
Bibliometria , Internet , Cirurgia Ortognática , Humanos , Internet/estatística & dados numéricos , Cirurgia Ortognática/estatística & dados numéricos , Cirurgia Ortognática/métodos , Procedimentos Cirúrgicos Ortognáticos/estatística & dados numéricos , Procedimentos Cirúrgicos Ortognáticos/métodos
7.
J Stomatol Oral Maxillofac Surg ; 125(3S): 101843, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38521241

RESUMO

OBJECTIVES: This work aims to introduce a Python-based algorithm and delve into the recent paradigm shift in Maxillofacial Surgery propelled by technological advancement. The provided code exemplifies the utilization of the MediaPipe library, created by Google in C++, with an additional Python interface available as a binding. TECHNICAL NOTE: The advent of FaceMesh coupled with artificial intelligence (AI), has brought about a transformative wave in contemporary maxillofacial surgery. This cutting-edge deep neural network, seamlessly integrated with Virtual Surgical Planning (VSP), offers surgeons precise 4D facial mapping capabilities. It accurately identifies facial landmarks, tailoring surgical interventions to individual patients, and streamlining the overall surgical procedure. CONCLUSION: FaceMesh emerges as a revolutionary tool in modern maxillofacial surgery. This deep neural network empowers surgeons with detailed insights into facial morphology, aiding in personalized interventions and optimizing surgical outcomes. The real-time assessment of facial dynamics contributes to improved aesthetic and functional results, particularly in complex cases like facial asymmetries or reconstructions. Additionally, FaceMesh has the potential for early detection of medical conditions and disease prediction, further enhancing patient care. Ongoing refinement and validation are essential to address limitations and ensure the reliability and effectiveness of FaceMesh in clinical settings.


Assuntos
Cirurgia Assistida por Computador , Humanos , Cirurgia Assistida por Computador/métodos , Face/cirurgia , Algoritmos , Inteligência Artificial , Pontos de Referência Anatômicos , Cirurgia Bucal/métodos , Redes Neurais de Computação , Imageamento Tridimensional/métodos , Procedimentos Cirúrgicos Bucais/métodos , Software
8.
J Stomatol Oral Maxillofac Surg ; 125(6): 101802, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38369024

RESUMO

OBJECTIVE: This study aims to comprehensively analyze the global landscape of oral and maxillofacial surgery (OMFS) literature through bibliometrics. The research focuses on evaluating publication trends, influential topics, and the impact of scholarly works within the field. METHODS: Following the principles of the Leiden Manifesto, a literature search was conducted using the Web of Science database, encompassing seven OMFS journals. A total of 18,218 publications were analyzed, with indicators such as publication language, geographic location, specialty, year, citation, and authorship examined. Statistical analyses, including Pearson correlation tests and angular coefficient calculations, were performed in RStudio. RESULTS: The study revealed a strong upward trend in publications related to orthognathic surgery, trauma, and infections. Geographic analysis indicated a dominance of European and Asian contributions, with the USA leading in overall publications. The impact of self-citations was explored, emphasizing nuanced perspectives on their role in scholarly impact metrics. The data provided insights into the scholarly impact of OMFS publications, including the H-index, number of citations, and citing articles. CONCLUSION: The findings underscored potential global discrepancies in OMFS research, both geographically and in terms of topics covered. The study discussed the influence of language and journal impact on citation counts, emphasizing the role of English publications. Specific topics, such as trauma and infections, exhibited high scholarly interest and citation rates. Recommendations were made to encourage submissions on specific topics, such as cosmetic surgery and pathology, to enhance the diversity of OMFS literature. The study aims to foster international collaboration and leverage bibliometrics for evidence-based decision-making, educational strategies, and advancements in the dynamic field of oral and maxillofacial surgery.

9.
J Stomatol Oral Maxillofac Surg ; 125(1): 101639, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37729964

RESUMO

OBJECTIVE: This study aimed to comprehensively review the literature and provide a practical guide for optimizing drug regimens and supplementation related to orthognathic surgery. METHODS: The authors conducted a thorough review of the existing literature, following the PRISMA-ScR guidelines. Various types of studies except case reports and reviews were included. The study applied specific inclusion criteria, focusing on perioperative and/or postoperative drugs, medications, or supplementation related to orthognathic surgery. RESULTS: This guide included 78 studies on various medications in orthognathic surgery. It encompasses clinical trials, cohort studies, cross-sectional studies, prospective and retrospective studies. The topics covered include antibiotics, analgesics, corticosteroids, antiemetics, hemostatic agents, local anesthetics, herbal medicine, and botulinum toxin. Pain and edema control involved specific medications, while local anesthesia utilized ropivacaine and bupivacaine. The guide also discusses mineral and vitamin supplementation. The effectiveness of hemostatic agents and antiemetics was highlighted. CONCLUSION: Pain management, reduced swelling, enhanced wound healing, and faster recovery are among the advantages. In addition to the standard drugs and medications, the inclusion of vitamin and mineral supplements, tranexamic acid, postoperative anesthetic blocks, and preemptive antiemetics is anticipated to offer various benefits in orthognathic surgery, despite the limited available evidence.


Assuntos
Antieméticos , Hemostáticos , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Estudos Retrospectivos , Procedimentos Cirúrgicos Ortognáticos/efeitos adversos , Estudos Prospectivos , Estudos Transversais , Edema , Vitaminas , Minerais , Suplementos Nutricionais
10.
Neurosurgery ; 94(4): 690-699, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37947407

RESUMO

BACKGROUND AND OBJECTIVES: Magnetic resonance-guided focused ultrasound (MRgFUS) central lateral thalamotomy (CLT) has not yet been validated for treating refractory neuropathic pain (NP). Our aim was to assess the safety and potential efficacy of MRgFUS CLT for refractory NP. METHODS: In this prospective, nonrandomized, single-arm, investigator-initiated phase I trial, patients with NP for more than 6 months related to phantom limb pain, spinal cord injury, or radiculopathy/radicular injury and who had undergone at least one previous failed intervention were eligible. The main outcomes were safety profile and pain as assessed using the brief pain inventory, the pain disability index, and the numeric rating scale. Medication use and the functional connectivity of the default mode network (DMN) were also assessed. RESULTS: Ten patients were enrolled, with nine achieving successful ablation. There were no serious adverse events and 12 mild/moderate severity events. The mean age was 50.9 years (SD: 12.7), and the mean symptom duration was 12.3 years (SD: 9.7). Among eight patients with a 1-year follow-up, the brief pain inventory decreased from 7.6 (SD: 1.1) to 3.8 (SD: 2.8), with a mean percent decrease of 46.3 (SD: 40.6) (paired t -test, P = .017). The mean pain disability index decreased from 43.0 (SD: 7.5) to 25.8 (SD: 16.8), with a mean percent decrease of 39.3 (SD: 41.6) ( P = .034). Numeric rating scale scores decreased from a mean of 7.2 (SD: 1.8) to 4.0 (SD: 2.8), with a mean percent decrease of 42.8 (SD: 37.8) ( P = .024). Patients with predominantly intermittent pain or with allodynia responded better than patients with continuous pain or without allodynia, respectively. Some patients decreased medication use. Resting-state functional connectivity changes were noted, from disruption of the DMN at baseline to reactivation of connectivity between DMN nodes at 3 months. CONCLUSION: MRgFUS CLT is feasible and safe for refractory NP and has potential utility in reducing symptoms as measured by validated pain scales.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Neuralgia , Humanos , Pessoa de Meia-Idade , Hiperalgesia , Neuralgia/diagnóstico por imagem , Neuralgia/cirurgia , Estudos Prospectivos , Tálamo/diagnóstico por imagem , Tálamo/cirurgia , Resultado do Tratamento , Adulto
11.
Int Orthop ; 47(12): 2977-2984, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37555849

RESUMO

PURPOSE: Acetabular fractures are associated to an increased risk of subsequent hip osteoarthritis. The only available score for post-operative reduction assessment in acetabular fractures (Matta's score) is x-ray based. CT-scan was shown superior to X-rays in post-operative reduction assessment. We aim to describe a CT-scan-based post-operative reduction score in acetabular fractures and evaluate its accuracy and reproducibility. METHODS: This is a retrospective study that includes 138 patients who underwent surgery for an acetabular fracture in our tertiary referral centre with a mean follow-up of 104.39±42.2 months. The post-operative CT-scan was reviewed and residual displacement (maximum gap and step) measured by three independent observers. The association between the occurrence of THA and the CT-scan measurements was evaluated. This led to a new prognostic score. The interobserver reliability and accuracy of this score were calculated. RESULTS: Interobserver reproducibility for the residual maximal gap was 0.82 (95% CI [0.70-0.89]) and 0.61 (95% CI [0.52-0.70]) for the residual maximal step displacement measurements. We created a score from a logistic regression model, attributing 1 point for every 1 mm of residual maximal step displacement and 1 point for every 2 mm of residual maximal gap displacement. The interobserver reproducibility of this score was 0.78 (95% CI [0.71-0.84]), and its AUC was 0.79 (95% CI [0.69-0.88]). CONCLUSION: This is the first CT-scan-based score for the assessment of residual displacement of a surgically treated acetabular fracture. It shows good interobserver reproducibility and accuracy in predicting the risk for secondary THA. It should be regularly used per-operatively (if per-operative 3D imaging is available) and post-operatively to predict the prognosis.


Assuntos
Artroplastia de Quadril , Fraturas Ósseas , Fraturas do Quadril , Fraturas da Coluna Vertebral , Humanos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Artroplastia de Quadril/métodos , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Fraturas da Coluna Vertebral/cirurgia , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Acetábulo/lesões , Resultado do Tratamento
13.
Int J Oral Maxillofac Surg ; 52(6): 691-695, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36115779

RESUMO

The aim of this technical note is to describe a protocol for three-dimensional virtual simulation of orthognathic surgery that has been designed to be easily implemented, without the need for any special clinical apparatus, software brand, or computed tomography sequence. The protocol comprises innovative concepts and simplified steps for image segmentation, creation of a composite skull, control of the condylar position, and sequencing of bimaxillary surgery. This protocol was applied by the developers in about 2000 cases performed between 2015 and 2022, and has become quite popular among local surgeons. Previous preliminary studies have shown that it meets the accuracy standards for clinical use, although further studies with larger numbers of patients are desirable for additional validation.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Cirurgia Assistida por Computador , Humanos , Procedimentos Cirúrgicos Ortognáticos/métodos , Imageamento Tridimensional/métodos , Crânio , Simulação por Computador , Cirurgia Assistida por Computador/métodos
14.
Sci Data ; 9(1): 453, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906241

RESUMO

Glioblastoma is the most common aggressive adult brain tumor. Numerous studies have reported results from either private institutional data or publicly available datasets. However, current public datasets are limited in terms of: a) number of subjects, b) lack of consistent acquisition protocol, c) data quality, or d) accompanying clinical, demographic, and molecular information. Toward alleviating these limitations, we contribute the "University of Pennsylvania Glioblastoma Imaging, Genomics, and Radiomics" (UPenn-GBM) dataset, which describes the currently largest publicly available comprehensive collection of 630 patients diagnosed with de novo glioblastoma. The UPenn-GBM dataset includes (a) advanced multi-parametric magnetic resonance imaging scans acquired during routine clinical practice, at the University of Pennsylvania Health System, (b) accompanying clinical, demographic, and molecular information, (d) perfusion and diffusion derivative volumes, (e) computationally-derived and manually-revised expert annotations of tumor sub-regions, as well as (f) quantitative imaging (also known as radiomic) features corresponding to each of these regions. This collection describes our contribution towards repeatable, reproducible, and comparative quantitative studies leading to new predictive, prognostic, and diagnostic assessments.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/fisiopatologia , Genômica , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Prognóstico
15.
J Stomatol Oral Maxillofac Surg ; 123(5): e251-e259, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35413462

RESUMO

We aimed to produce a narrative review of planning orthognathic surgery, chronologically. Also, to present flaws of methods and the future of orthognathic surgery planning. The search was carried out mainly in PubMed, SCOPUS, Embase, and Cochrane databases. Also was complemented by manual search in reference lists from identified studies and in grey literature. The first orthognathic surgery was reported in 1849, and it took more than a century for the development of the traditional orthognathic 2D planning. Besides the advances, surgeons observed failures and lacks on 2D method in representing with reliability the facial and maxillary tridimensional structure (3D). With technological developments in 90s and 2000s, methodological improvements were granted, and the 3D protocol was created. The CASS and Charlotte protocols were the earliest 3D planning protocols conceived. Since then, some steps were simplified, and new technologies are being developed and added to create a more reliable and precise way of planning orthognathic surgery.


Assuntos
Cirurgia Ortognática , Cirurgia Assistida por Computador , Humanos , Imageamento Tridimensional/métodos , Maxila/cirurgia , Planejamento de Assistência ao Paciente , Reprodutibilidade dos Testes , Cirurgia Assistida por Computador/métodos
16.
J Magn Reson Imaging ; 55(6): 1710-1722, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34741576

RESUMO

BACKGROUND: Arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) denoising through deep learning (DL) often faces insufficient training data from patients. One solution is to train DL models using healthy subjects' data which are more widely available and transfer them to patients' data. PURPOSE: To evaluate the transferability of a DL-based ASL MRI denoising method (DLASL). STUDY TYPE: Retrospective. SUBJECTS: Four hundred and twenty-eight subjects (189 females) from three cohorts. FIELD STRENGTH/SEQUENCE: 3 T two-dimensional (2D) echo-planar imaging (EPI)-based pseudo-continuous ASL (PCASL) and 2D EPI-based pulsed ASL (PASL) sequences. ASSESSMENT: DLASL was trained using young healthy adults' PCASL data (Dataset 1: 250/30 subjects as training/validation set) and was directly transferred (DTF) to PCASL data from Dataset 2 (45 subjects test set) of normal controls (NC) and Alzheimer's disease (AD) groups. DLASL was fine-tuned (DLASLFT) and tested on PASL data from Dataset 3 (103 subjects test set) of NC and AD. An existing non-DL method (NonDL) was used for comparison. Cerebral blood flow (CBF) images from ASL MRI were compared between NC and AD to assess characteristic hypoperfusion (lower CBF) patterns in AD. CBF image quality and CBF map sensitivity for detecting hypoperfusion using peak t-value and suprathreshold cluster size are outcome measures. STATISTICAL TESTS: Paired t-test, two-sample t-test, one-way analysis of variance, and Tukey honestly significant difference, and linear mixed-effects models were used. P < 0.05 was considered statistically significant. RESULTS: Mean contrast-to-noise ratio (CNR) of Dataset 2 showed that DTF outperformed NonDL (AD: 3.38 vs. 2.64, NC: 3.80 vs. 3.36). On Dataset 3, DLASLFT outperformed NonDL measured by mean CNR (AD: 2.45 vs. 1.87, NC: 2.54 vs. 2.17) and mean radiologic score (2.86 vs. 2.44). Image quality improvement was significant on both test sets. DTF and DLASLFT improved sensitivity for detecting AD-related hypoperfusion patterns compared with NonDL. DATA CONCLUSION: We demonstrated the DLASL's transferability across different ASL sequences and different populations. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Doença de Alzheimer , Aprendizado Profundo , Adulto , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/patologia , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Perfusão , Estudos Retrospectivos , Marcadores de Spin
17.
J Stomatol Oral Maxillofac Surg ; 123(3): 345-352, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34237437

RESUMO

We aimed to evaluate whether there is a consensus among bi- (2D) and three-dimensional (3D) evaluations of mandible condyle position and its rotation center. Also, if this data can be replicated in orthognathic surgery planning. The survey was carried out on the major databases (PubMed, SCOPUS, Embase, Cochrane). Human or human bio models evaluations in 2D or 3D of mandibular condylar position concerning its fossa and rotational axis for orthognathic surgery planning were eligible. The heterogeneity of the studies and uncertainties in methodological biases did not allow us to identify the superiority of 2D or 3D methodology in determination of the condylar rotational axis. There is a lot of divergences in the definition of occlusal relationships among dental specialties. Although there was no consensus regarding condylar position in relation to the fossa, the most reported axis of rotation was positioned posterior-inferior. Weak scientific evidence and divergences in dental vocabulary shows the need for clinical studies with more accurate and transparent methodological design to standardize concepts. Despite we cannot affirm, we can suggest that the centric relation (CR) is not the condylar position when clinically manipulated in the posterior superior direction. This condylar position is the retruded contact position (RCt) while CR is the functional position of the condyle. In this way, the orthognathic surgery has two occlusal relationships during planning and execution. The ideal axis of rotation for orthognathic surgery planning must be fixed, permit individualization for each condyle and be reproducible. The 2D planning is obsolete as cannot provide all the necessary tools for an accurate planning.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/cirurgia , Rotação
18.
Front Neurol ; 12: 669449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220679

RESUMO

Stem cell and immune cell therapies are being investigated as a potential therapeutic modality for CNS disorders, performing functions such as targeted drug or growth factor delivery, tumor cell destruction, or inflammatory regulation. Despite promising preclinical studies, delivery routes for maximizing cell engraftment, such as stereotactic or intrathecal injection, are invasive and carry risks of hemorrhage and infection. Recent developments in MRI-guided focused ultrasound (MRgFUS) technology have significant implications for treating focal CNS pathologies including neurodegenerative, vascular and malignant processes. MRgFUS is currently employed in the clinic for treating essential tremor and Parkinson's Disease by producing precise, incisionless, transcranial lesions. This non-invasive technology can also be modified for non-destructive applications to safely and transiently open the blood-brain barrier (BBB) to deliver a range of therapeutics, including cells. This review is meant to familiarize the neuro-interventionalist with this topic and discusses the use of MRgFUS for facilitating cellular delivery to the brain. A detailed and comprehensive description is provided on routes of cell administration, imaging strategies for targeting and tracking cellular delivery and engraftment, biophysical mechanisms of BBB enhanced permeability, supportive proof-of-concept studies, and potential for clinical translation.

19.
Metabolites ; 11(6)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073714

RESUMO

Hyperpolarized magnetic resonance spectroscopic imaging (MRSI) of [1-13C]pyruvate metabolism has previously been used to assess the effects of traumatic brain injury (TBI) in rats. Here, we show that MRSI can be used in conjunction with dichloroacetate to measure the phosphorylation state of pyruvate dehydrogenase (PDH) following mild-to-moderate TBI, and that measurements can be repeated in a longitudinal study to monitor the course of injury progression and recovery. We found that the level of 13C-bicarbonate and the bicarbonate-to-lactate ratio decreased on the injured side of the brain four hours after injury and continued to decrease through day 7. Levels recovered to normal by day 28. Measurements following dichloroacetate administration showed that PDH was inhibited equally by PDH kinase (PDK) on both sides of the brain. Therefore, the decrease in aerobic metabolism is not due to inhibition by PDK.

20.
Int Orthop ; 45(7): 1837-1844, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34021374

RESUMO

INTRODUCTION: The use of per-operative cone beam tomography imaging for displaced acetabular fractures yields increased post-operative articular reduction accuracy. This study evaluates the need for total hip replacement (THR) and hip-related functional outcomes in patients with displaced acetabular fractures treated with O-ARM guidance compared to those treated under C-ARM guidance. MATERIALS AND METHODS: This is a prospective matched cohort study. Adult patients (35) with acetabular fractures operated under O-ARM guidance were included. These were matched (age, fracture type) to classically treated patients (35) from our data base. The primary outcome was the need for THR during three year follow-up period. Secondary outcomes were functional scores [Harris Hip score (HHS), Postel-Merle d'Aubigné (PMA)] and hip osteoarthritis grade at three year follow-up. Correlation between reduction gap and THR was evaluated. RESULTS: At three years, five patients were lost to follow-up in O-ARM group and four in control group. Two patients (6.66%) in the O-ARM group needed THR compared to eight patients in controls (25.80%) (p = 0.046). Hip X-ray osteoarthritis grade averaged 0.00 in patients without THR in O-ARM group compared to 0.22 in patients without THR in controls (p = 0.008). HHS averaged 95.79 in patients without THR in O-ARM group, compared to 93.82 in patients without THR in the control group (p = 0.41%). PMA averaged 17.25 in patients without THR in the O-ARM group compared to 17.04 in patients without THR in group 2 (p = 0.37). Evaluation of correlation between reduction gap and THR rate yielded OR = 1.22 (1.06-1.45). DISCUSSION: Increased accuracy in articular reduction, with per-operative three-dimensional control of impaction, in acetabular fractures led to significantly less need for THR in patients treated under O-ARM. Patients in both groups are comparable for functional outcomes because those with the lowest scores were offered THR. Per-operative cone beam guidance and navigation use are recommended in tertiary referral centres for acetabular trauma.


Assuntos
Artroplastia de Quadril , Fraturas Ósseas , Cirurgia Assistida por Computador , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Adulto , Estudos de Coortes , Seguimentos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Imageamento Tridimensional , Estudos Prospectivos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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