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1.
Skin Res Technol ; 30(3): e13622, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38500350

RESUMO

BACKGROUND AND OBJECTIVE: Skin thermal diffusivity plays a crucial role in various applications, including laser therapy and cryogenic skin cooling.This study investigates the correlation between skin thermal diffusivity and two important skin parameters, melanin content and erythema, in a cohort of 102 participants. METHODS: An in-house developed device based on transient temperature measurement was used to assess thermal diffusivity at different body locations. Melanin content and erythema were measured using a colorimeter. Statistical analysis was performed to examine potential correlations. RESULTS: The results showed that the measured thermal diffusivity values were consistent with previous reports, with variations observed among subjects. No significant correlation was found between thermal diffusivity and melanin content or erythema. This suggests that other factors, such as skin hydration or epidermis thickness, may have a more dominant influence on skin thermal properties. CONLCUSION: This research provides valuable insights into the complex interplay between skin thermal properties and physiological parameters, with potential implications for cosmetic and clinical dermatology applications.


Assuntos
Melaninas , Pigmentação da Pele , Humanos , Pele/diagnóstico por imagem , Eritema , Epiderme
2.
Artigo em Inglês | MEDLINE | ID: mdl-38411348

RESUMO

BACKGROUND: Artificial intelligence (AI) shows promising potential to enhance human decision-making as synergistic augmented intelligence (AuI), but requires critical evaluation for skin cancer screening in a real-world setting. OBJECTIVES: To investigate the perspectives of patients and dermatologists after skin cancer screening by human, artificial and augmented intelligence. METHODS: A prospective comparative cohort study conducted at the University Hospital Basel included 205 patients (at high-risk of developing melanoma, with resected or advanced disease) and 8 dermatologists. Patients underwent skin cancer screening by a dermatologist with subsequent 2D and 3D total-body photography (TBP). Any suspicious and all melanocytic skin lesions ≥3 mm were imaged with digital dermoscopes and classified by corresponding convolutional neural networks (CNNs). Excisions were performed based on dermatologist's melanoma suspicion, study-defined elevated CNN risk-scores and/or melanoma suspicion by AuI. Subsequently, all patients and dermatologists were surveyed about their experience using questionnaires, including quantification of patient's safety sense following different examinations (subjective safety score (SSS): 0-10). RESULTS: Most patients believed AI could improve diagnostic performance (95.5%, n = 192/201). In total, 83.4% preferred AuI-based skin cancer screening compared to examination by AI or dermatologist alone (3D-TBP: 61.3%; 2D-TBP: 22.1%, n = 199). Regarding SSS, AuI induced a significantly higher feeling of safety than AI (mean-SSS (mSSS): 9.5 vs. 7.7, p < 0.0001) or dermatologist screening alone (mSSS: 9.5 vs. 9.1, p = 0.001). Most dermatologists expressed high trust in AI examination results (3D-TBP: 90.2%; 2D-TBP: 96.1%, n = 205). In 68.3% of the examinations, dermatologists felt that diagnostic accuracy improved through additional AI-assessment (n = 140/205). Especially beginners (<2 years' dermoscopic experience; 61.8%, n = 94/152) felt AI facilitated their clinical work compared to experts (>5 years' dermoscopic experience; 20.9%, n = 9/43). Contrarily, in divergent risk assessments, only 1.5% of dermatologists trusted a benign CNN-classification more than personal malignancy suspicion (n = 3/205). CONCLUSIONS: While patients already prefer AuI with 3D-TBP for melanoma recognition, dermatologists continue to rely largely on their own decision-making despite high confidence in AI-results. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04605822).

3.
Arch Orthop Trauma Surg ; 144(3): 1029-1038, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38091069

RESUMO

INTRODUCTION: The assessment of the knee alignment on long leg radiographs (LLR) postoperative to corrective knee osteotomies (CKOs) is highly dependent on the reader's expertise. Artificial Intelligence (AI) algorithms may help automate and standardise this process. The study aimed to analyse the reliability of an AI-algorithm for the evaluation of LLRs following CKOs. MATERIALS AND METHODS: In this study, we analysed a validation cohort of 110 postoperative LLRs from 102 patients. All patients underwent CKO, including distal femoral (DFO), high tibial (HTO) and bilevel osteotomies. The agreement between manual measurements and the AI-algorithm was assessed for the mechanical axis deviation (MAD), hip knee ankle angle (HKA), anatomical-mechanical-axis-angle (AMA), joint line convergence angle (JLCA), mechanical lateral proximal femur angle (mLPFA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibia angle (mMPTA) and mechanical lateral distal tibia angle (mLDTA), using the intra-class-correlation (ICC) coefficient between the readers, each reader and the AI and the mean of the manual reads and the AI-algorithm and Bland-Altman Plots between the manual reads and the AI software for the MAD, HKA, mLDFA and mMPTA. RESULTS: In the validation cohort, the AI software showed excellent agreement with the manual reads (ICC: 0.81-0.99). The agreement between the readers (Inter-rater) showed excellent correlations (ICC: 0.95-0. The mean difference in the DFO group for the MAD, HKA, mLDFA and mMPTA were 0.50 mm, - 0.12°, 0.55° and 0.15°. In the HTO group the mean difference for the MAD, HKA, mLDFA and mMPTA were 0.36 mm, - 0.17°, 0.57° and 0.08°, respectively. Reliable outputs were generated in 95.4% of the validation cohort. CONCLUSION:  he application of AI-algorithms for the assessment of lower limb alignment on LLRs following CKOs shows reliable and accurate results. LEVEL OF EVIDENCE: Diagnostic Level III.


Assuntos
Inteligência Artificial , Osteoartrite do Joelho , Masculino , Humanos , Reprodutibilidade dos Testes , Perna (Membro) , Estudos Retrospectivos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Extremidade Inferior , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Osteoartrite do Joelho/cirurgia , Osteotomia/métodos
4.
Br J Cancer ; 129(11): 1780-1786, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37813959

RESUMO

BACKGROUND: Short-term infusions of dinutuximab beta plus isotretinoin and cytokines administered in previous immunotherapy studies in neuroblastoma were associated with severe pain. Here, long-term, continuous infusion of single-agent dinutuximab beta was evaluated in patients with relapsed/refractory neuroblastoma. METHODS: In this open-label, single-arm, Phase 2 study, patients with either refractory or relapsed high-risk neuroblastoma received dinutuximab beta by continuous infusion over 10 days of each cycle, for up to five cycles. The primary endpoint was objective response rate 24 weeks after the end of cycle 5. Secondary endpoints included adverse events, intravenous morphine use, best response, duration of response, and three-year progression-free and overall survival. RESULTS: Of the 40 patients included, 38 had evaluable response. Objective response rate was 26% and best response rate 37%. Median duration of response was 238 days (IQR 108-290). Three-year progression-free and overall survival rates were 31% (95% CI 17-47) and 66% (95% CI 47-79), respectively. Prophylactic intravenous morphine use and duration of use decreased with increasing cycles. The most common grade 3 treatment-related adverse events were pain, diarrhea, and hypokalemia. CONCLUSION: Long-term continuous infusion of single-agent dinutuximab beta is tolerable and associated with clinically meaningful responses in patients with relapsed/refractory high-risk neuroblastoma. CLINICAL TRIAL REGISTRATION: The study is registered with ClinicalTrials.gov (NCT02743429) and EudraCT (2014-000588-42).


Assuntos
Neuroblastoma , Humanos , Derivados da Morfina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/etiologia , Neuroblastoma/tratamento farmacológico , Dor/tratamento farmacológico , Dor/etiologia
5.
Knee Surg Sports Traumatol Arthrosc ; 31(10): 4220-4230, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37286901

RESUMO

PURPOSE: Osteoarthritis of the knee is commonly associated with malalignment of the lower limb. Recent classifications, as the Coronal Plane Alignment of the Knee (CPAK) and Functional Phenotype classification, describe the bony knee morphology in addition to the overall limb alignment. Data on distribution of these classifications is not sufficient in large populations. The aim of this study was to analyse the preoperative knee morphology with regard to the aforementioned classifications in long leg radiographs prior to total knee arthroplasty surgery using Artificial Intelligence. METHODS: The cohort comprised 8739 preoperative long leg radiographs of 7456 patients of all total knee arthroplasty surgeries between 2009 and 2021 from our institutional database. The automated measurements were performed with the validated Artificial Intelligence software LAMA (ImageBiopsy Lab, Vienna) and included standardized axes and angles [hip-knee-ankle angle (HKA), mechanical lateral distal femur angle (mLDFA), mechanical medial proximal tibia angle (mMPTA), mechanical axis deviation (MAD), anatomic mechanic axis deviation (AMA) and joint line convergence angle (JLCA)]. CPAK and functional phenotype classifications were performed and all measurements were analysed for gender, age, and body mass index (BMI) within these subgroups. RESULTS: Varus alignment was more common in men (m: 2008, 68.5%; f: 2953, 50.8%) while neutral (m: 578, 19.7%; f: 1357, 23.4%) and valgus (m: 345, 11.8%; f: 1498, 25.8%) alignment was more common in women. The most common morphotypes according to CPAK classification were CPAK Type I (2454; 28.1%), Type II (2383; 27.3%), and Type III (1830; 20.9%). An apex proximal joint line (CPAK Type VII, VIII and IX) was only found in 1.3% of all cases (n = 121). In men, CPAK Type I (1136; 38.8%) and CPAK Type II (799; 27.3%) were the most common types and women were spread more equally between CPAK Type I (1318; 22.7%), Type II (1584; 27.3%) and Type III (1494; 25.7%) (p < 0.001). The most common combination of femur and tibia types was NEUmLDFA0°,NEUmMPTA0° (m: 514, 17.5%; f: 1004, 17.3%), but men showed femoral varus more often. Patients with a higher BMI showed a significantly lower age at surgery (R2 = 0.09, p < 0.001). There were significant differences between men and women for all radiographic parameters (p < 0.001). CONCLUSION: Distribution in knee morphology with gender-specific differences highlights the wide range in osteoarthritic knees, characterized by CPAK and phenotype classification and may influence future surgical planning. LEVEL OF EVIDENCE: Level III.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Feminino , Inteligência Artificial , Estudos Retrospectivos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Extremidade Inferior , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Fenótipo
6.
Int Orthop ; 47(4): 945-953, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36799971

RESUMO

PURPOSE: Despite advances of three-dimensional imaging pelvic radiographs remain the cornerstone in the evaluation of the hip joint. However, large inter- and intra-rater variabilities were reported due to subjective landmark setting. Artificial intelligence (AI)-powered software applications could improve the reproducibility of pelvic radiograph evaluation by providing standardized measurements. The aim of this study was to evaluate the reliability and agreement of a newly developed AI algorithm for the evaluation of pelvic radiographs. METHODS: Three-hundred pelvic radiographs from 280 patients with different degrees of acetabular coverage and osteoarthritis (Tönnis Grade 0 to 3) were evaluated. Reliability and agreement between manual measurements and the outputs of the AI software were assessed for the lateral-center-edge (LCE) angle, neck-shaft angle, sharp angle, acetabular index, as well as the femoral head extrusion index. RESULTS: The AI software provided reliable results in 94.3% (283/300). The ICC values ranged between 0.73 for the Acetabular Index to 0.80 for the LCE Angle. Agreement between readers and AI outputs, given by the standard error of measurement (SEM), was good for hips with normal coverage (LCE-SEM: 3.4°) and no osteoarthritis (LCE-SEM: 3.3°) and worse for hips with undercoverage (LCE-SEM: 5.2°) or severe osteoarthritis (LCE-SEM: 5.1°). CONCLUSION: AI-powered applications are a reliable alternative to manual evaluation of pelvic radiographs. While being accurate for patients with normal acetabular coverage and mild signs of osteoarthritis, it needs improvement in the evaluation of patients with hip dysplasia and severe osteoarthritis.


Assuntos
Impacto Femoroacetabular , Osteoartrite , Humanos , Reprodutibilidade dos Testes , Inteligência Artificial , Articulação do Quadril/diagnóstico por imagem , Acetábulo , Software , Estudos Retrospectivos
7.
J Dtsch Dermatol Ges ; 21(3): 239-243, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36892188

RESUMO

Colchicine, which was already used by the ancient Egyptians, has recently experienced a renaissance in various medical disciplines, including dermatology. However, due to the potentially significant side effects of systemic use, many clinicians are cautious in their use of colchicine. This review provides a practical overview of the data on the established and emerging use of systemic and topical colchicine in dermatologic diseases.


Assuntos
Colchicina , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Colchicina/uso terapêutico , Colchicina/farmacologia
8.
J Trauma Stress ; 31(6): 795-804, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30431683

RESUMO

Forced migration is one of the major challenges currently facing the international community. Many refugees have been affected by traumatic experiences at home and during their flight, putting them at a heightened risk of developing trauma-related disorders. The new version of the International Classification of Diseases (ICD-11) introduced two sibling disorders, posttraumatic stress disorder (PTSD) and complex PTSD (CPTSD). So far, little is known about risk and protective factors in refugees that are specifically associated with the disturbances in self-organization (DSO) characteristic of CPTSD. In this study, we aimed to investigate the association between PTSD and DSO symptoms and traumatic experiences, postmigration difficulties, and social support in a culturally diverse sample of refugees who resettled in Switzerland. A total of 94 refugees (85.1% male; M age = 31.60 years, SD = 10.14, range: 18-61 years) participated in this study. Trained assessors performed either guided questionnaire assessments or structured interviews. In our advice- and help-seeking sample, 32.9% of individuals suffered from PTSD and 21.3% from CPTSD. After controlling for potential gender differences, we found positive associations between PTSD symptoms and trauma exposure, ß = .22, as well as between DSO symptoms and postmigration living difficulties, ß = .42, and lack of social support, ß = .22. Our findings support the notion that it is highly important to consider differential associations among PTSD and DSO symptoms and risk and protective factors to gain a deeper understanding of the trauma-related problems refugees face.


Assuntos
Refugiados/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Adolescente , Adulto , Estudos Transversais , Depressão/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Refugiados/estatística & dados numéricos , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/classificação , Transtornos de Estresse Pós-Traumáticos/complicações , Inquéritos e Questionários , Adulto Jovem
11.
J Knee Surg ; 37(1): 8-13, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37734406

RESUMO

The use of robotic-assisted surgery (RAS) in total knee arthroplasty (TKA) is becoming increasingly popular due to better precision, potentially superior outcomes and the ability to achieve alternative alignment strategies. The most commonly used alignment strategy with RAS is a modification of mechanical alignment (MA), labeled adjusted MA (aMA). This strategy allows slight joint line obliquity of the tibial component to achieve superior balancing. In the present study, we compared coronal alignment after TKA using RAS with aMA and computer-assisted surgery (CAS) with MA that has been the standard in the center for more than 10 years. We analyzed a prospectively collected database of patients undergoing TKA in a single center. Lateral distal femoral angle (LDFA) and medial proximal tibial angle (MPTA) were compared for both techniques. In 140 patients, 68 CASs and 72 RASs, we observed no difference in postoperative measurements (median 90 degrees for all, LDFA p = 0.676, MPTA p = 0.947) and no difference in outliers <2 degrees (LDFA p = 0.540, MPTA p = 0.250). The present study demonstrates no benefit in eliminating outliers or achieving neutral alignment of both the femoral and the tibial components in robotic-assisted versus computer-assisted TKA if MA is the target. To utilize the precision of RAS, it is recommended to aim for more personalized alignment strategies. The level of evidence is level III retrospective study.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Procedimentos Cirúrgicos Robóticos , Robótica , Cirurgia Assistida por Computador , Humanos , Artroplastia do Joelho/métodos , Estudos Retrospectivos , Cirurgia Assistida por Computador/métodos , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia
12.
J Mech Behav Biomed Mater ; 150: 106333, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134586

RESUMO

The fibro-cartilaginous labrum surrounds the acetabular rim and is important for hip joint stability and sealing. Sealing may be enhanced by swelling pressure within the normal labrum. Swelling of the degenerated or torn labrum might occur and potentially contribute to the development of osteoarthritis, through altered load transmission. This study aimed to characterize the three-dimensional swelling behaviour, the collagen fiber orientation and spatial proteoglycan distribution of the bovine acetabular labrum. Specimens were harvested from bovine donors (192-652 days, male, n = 6 donors). Structure was analyzed by scanning electron microscopy, histology, and dimethylmethylene blue assay. Specimen dimensions were measured before and after incubation in phosphate buffered saline to assess the swelling. Results showed that the articulating surface is composed of a collagen mesh network. Collagen fiber bundles showed a low degree of alignment close to the surface and were circumferentially aligned in the deep tissue. Proteoglycans were identified clustered between the collagen bundles. Glycosaminoglycan content was 10 x lower than that of cartilage (23.1 ± 6.4 compared to 299.5 ± 19.1 µg/mg dry weight) with minor regional differences. Specimens swelled significantly more in the orthogonal direction (swelling ratio 124.7 ± 10.2%) compared to the swelling parallel to the articulating surface (108.8 ± 6.1% and 102.8 ± 4.1%). In the deep tissue, swelling was also restricted in the main collagen fiber bundle direction (circumferentially), with a swelling ratio of 109.5 ± 4.0% in the main fiber bundle direction compared to 126.8 ± 7.3 % and 122.3 ± 5.8% radially. The findings demonstrate that the labrum shows anisotropic swelling properties, which reflect the anisotropy in the tissue structure and inter-fiber localisation of proteoglycans.


Assuntos
Acetábulo , Cartilagem Articular , Masculino , Animais , Bovinos , Anisotropia , Cartilagem Articular/patologia , Articulação do Quadril , Colágeno , Proteoglicanas
13.
J Bone Joint Surg Am ; 106(11): 941-949, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38512965

RESUMO

BACKGROUND: Osseointegration is essential for the long-term survival of cementless femoral stems and is dependent on periprosthetic bone quality and correct implantation technique. The aim of this study was to evaluate the 3-dimensional long-term fixation patterns of, and bone microarchitecture around, cementless hip stems. METHODS: Four specimens with varying degrees of bone quality and fixation characteristics from body donors who had received Alloclassic Zweymüller hip stems during their lifetime (mean time in situ at the time of death: 12.73 years) were evaluated with use of radiographs, high-resolution computed tomography (CT) scans, and hard-tissue histology. The CT voxel size was 85 µm, and the following parameters were calculated: total bone volume, total bone volume fraction, trabecular bone volume, trabecular bone volume fraction, cortical bone volume, cortical bone volume fraction, and cortical thickness. Bone-implant contact and canal fill index values for each Gruen zone of the specimens were calculated with use of histological samples. RESULTS: Femoral stems with apparently good cortical contact on clinical radiographs showed higher values for cortical bone volume, trabecular bone volume, and cortical thickness in the high-resolution CT analysis than femoral stems with apparently weak cortical contact on clinical radiographs. Based on the histological evaluation, the mean bone-implant contact ranged from 22.94% to 57.24% and the mean canal fill index ranged from 52.33% to 69.67% among the specimens. CONCLUSIONS: This study demonstrated different osseointegration patterns of cementless femoral stems on the basis of radiographs, high-resolution CT scans, and histological evaluation. Femora with high cortical bone volume and cortical thickness were associated with higher canal fill indices, whereas femora with low cortical bone volume and cortical thickness had lower canal fill indices and showed a characteristic corner-anchorage pattern. CLINICAL RELEVANCE: Osseointegration patterns and thus the long-term survival of cementless femoral stems are dependent on cortical bone volume and cortical thickness.


Assuntos
Fêmur , Prótese de Quadril , Osseointegração , Tomografia Computadorizada por Raios X , Osseointegração/fisiologia , Humanos , Fêmur/diagnóstico por imagem , Masculino , Feminino , Idoso , Artroplastia de Quadril/métodos , Pessoa de Meia-Idade , Desenho de Prótese , Imageamento Tridimensional
14.
Gene ; 856: 147140, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36574933

RESUMO

The labrum is a fibrocartilaginous ring surrounding the acetabulum. Loss of labrum function contributes to the degeneration of the hip joint, leading to osteoarthritis. Successful labrum restoration requires profound knowledge about the tissue being replaced. The aim of this study was to characterize the transcriptome and the mechanobiological function of the labrum. RNA-seq was performed to compare the transcriptome of bovine labrum against articular cartilage tissue. Differential expression and gene ontology (GO) term pathway analysis were applied using the SUSHI framework. Bovine labrum explants were cultured for 5 days with / without mechanical loading and targeted gene expression was analyzed by real time quantitative polymerase chain reaction. More than 6'000 genes were significantly differentially expressed in the labrum compared to cartilage. Up- and downregulated genes were associated with the GO term extracellular matrix organization. The study established an extracellular matrix gene expression profile of healthy labrum tissue and identified significantly upregulated extracellular matrix related genes compared to cartilage tissue. Mechanical loading significantly upregulated aggrecan (ACAN), cartilage oligomeric matrix protein (COMP), fibronectin (FN1) and proteoglycan 4 (PRG4). MMP1/3/9 and IL6, which were upregulated by an inflammatory stimulus (IL-1b), were statistically unaffected by the loading, although IL6 was upregulated in each donor immediately after the loading. Unique ECM related features may guide the development of labrum tissue-engineering solutions. Despite the transcriptome differences between labrum and cartilage tissue, gene expression response to mechanical loading showed similarities with previously reported responses in cartilage, indicating a preserved tissue adaptation mechanism to mechanical loading. Running title: Acetabular Labrum Mechanobiology.


Assuntos
Cartilagem Articular , Transcriptoma , Animais , Bovinos , Acetábulo/metabolismo , Cartilagem Articular/metabolismo , Articulação do Quadril/fisiologia , Interleucina-6/metabolismo
15.
J Bone Joint Surg Am ; 105(8): 620-629, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36848437

RESUMO

BACKGROUND: Metal artifacts caused by hip arthroplasty stems limit the diagnostic value of computed tomography (CT) in the evaluation of periprosthetic fractures or implant loosening. The aim of this ex vivo study was to evaluate the influence of different scan parameters and metal artifact algorithms on image quality in the presence of hip stems. METHODS: Nine femoral stems, 6 uncemented and 3 cemented, that had been implanted in subjects during their lifetimes were exarticulated and investigated after death and anatomical body donation. Twelve CT protocols consisting of single-energy (SE) and single-source consecutive dual-energy (DE) scans with and without an iterative metal artifact reduction algorithm (iMAR; Siemens Healthineers) and/or monoenergetic reconstructions were compared. Streak and blooming artifacts as well as subjective image quality were evaluated for each protocol. RESULTS: Metal artifact reduction with iMAR significantly reduced the streak artifacts in all investigated protocols (p = 0.001 to 0.01). The best subjective image quality was observed for the SE protocol with a tin filter and iMAR. The least streak artifacts were observed for monoenergetic reconstructions of 110, 160, and 190 keV with iMAR (standard deviation of the Hounsfield units: 151.1, 143.7, 144.4) as well as the SE protocol with a tin filter and iMAR (163.5). The smallest virtual growth was seen for the SE with a tin filter and without iMAR (4.40 mm) and the monoenergetic reconstruction of 190 keV without iMAR (4.67 mm). CONCLUSIONS: This study strongly suggests that metal artifact reduction algorithms (e.g., iMAR) should be used in clinical practice for imaging of the bone-implant interface of prostheses with either an uncemented or cemented femoral stem. Among the iMAR protocols, the SE protocol with 140 kV and a tin filter produced the best subjective image quality. Furthermore, this protocol and DE monoenergetic reconstructions of 160 and 190 keV with iMAR achieved the lowest levels of streak and blooming artifacts. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia de Quadril , Artefatos , Humanos , Estanho , Metais , Tomografia Computadorizada por Raios X/métodos , Algoritmos
16.
Bioengineering (Basel) ; 10(7)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37508797

RESUMO

Osteoarthritis scaffold-based grafts fail because of poor integration with the surrounding soft tissue and inadequate tribological properties. To circumvent this, we propose electrospun poly(ε-caprolactone)/zein-based scaffolds owing to their biomimetic capabilities. The scaffold surfaces were characterized using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, static water contact angles, and profilometry. Scaffold biocompatibility properties were assessed by measuring protein adsorption (Bicinchoninic Acid Assay), cell spreading (stained F-actin), and metabolic activity (PrestoBlue™ Cell Viability Reagent) of primary bovine chondrocytes. The data show that zein surface segregation in the membranes not only completely changed the hydrophobic behavior of the materials, but also increased the cell yield and metabolic activity on the scaffolds. The surface segregation is verified by the infrared peak at 1658 cm-1, along with the presence and increase in N1 content in the survey XPS. This observation could explain the decrease in the water contact angles from 125° to approximately 60° in zein-comprised materials and the decrease in the protein adsorption of both bovine serum albumin and synovial fluid by half. Surface nano roughness in the PCL/zein samples additionally benefited the radial spreading of bovine chondrocytes. This study showed that co-electrospun PCL/zein scaffolds have promising surface and biocompatibility properties for use in articular-tissue-engineering applications.

17.
Sci Rep ; 13(1): 8504, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231033

RESUMO

Artificial-intelligence (AI) allows large-scale analyses of long-leg-radiographs (LLRs). We used this technology to derive an update for the classical regression formulae by Trotter and Gleser, which are frequently used to infer stature based on long-bone measurements. We analyzed calibrated, standing LLRs from 4200 participants taken between 2015 and 2020. Automated landmark placement was conducted using the AI-algorithm LAMA™ and the measurements were used to determine femoral, tibial and total leg-length. Linear regression equations were subsequently derived for stature estimation. The estimated regression equations have a shallower slope and larger intercept in males and females (Femur-male: slope = 2.08, intercept = 77.49; Femur-female: slope = 1.9, intercept = 79.81) compared to the formulae previously derived by Trotter and Gleser 1952 (Femur-male: slope = 2.38, intercept = 61.41; Femur-female: slope = 2.47, intercept = 54.13) and Trotter and Gleser 1958 (Femur-male: slope = 2.32, intercept = 65.53). All long-bone measurements showed a high correlation (r ≥ 0.76) with stature. The linear equations we derived tended to overestimate stature in short persons and underestimate stature in tall persons. The differences in slopes and intercepts from those published by Trotter and Gleser (1952, 1958) may result from an ongoing secular increase in stature. Our study illustrates that AI-algorithms are a promising new tool enabling large-scale measurements.


Assuntos
Inteligência Artificial , Estatura , Humanos , Masculino , Feminino , Perna (Membro) , Tíbia/diagnóstico por imagem , Tíbia/anatomia & histologia , Fêmur/diagnóstico por imagem , Fêmur/anatomia & histologia , Antropologia Forense
18.
Eur J Cancer ; 190: 112954, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37453242

RESUMO

BACKGROUND: Convolutional neural networks (CNNs) have outperformed dermatologists in classifying pigmented skin lesions under artificial conditions. We investigated, for the first time, the performance of three-dimensional (3D) and two-dimensional (2D) CNNs and dermatologists in the early detection of melanoma in a real-world setting. METHODS: In this prospective study, 1690 melanocytic lesions in 143 patients with high-risk criteria for melanoma were evaluated by dermatologists, 2D-FotoFinder-ATBM and 3D-Vectra WB360 total body photography (TBP). Excision was based on the dermatologists' dichotomous decision, an elevated CNN risk score (study-specific malignancy cut-off: FotoFinder >0.5, Vectra >5.0) and/or the second dermatologist's assessment with CNN support. The diagnostic accuracy of the 2D and 3D CNN classification was compared with that of the dermatologists and the augmented intelligence based on histopathology and dermatologists' assessment. Secondary end-points included reproducibility of risk scores and naevus counts per patient by medical staff (gold standard) compared to automated 3D and 2D TBP CNN counts. RESULTS: The sensitivity, specificity, and receiver operating characteristics area under the curve (ROC-AUC) for risk-score-assessments compared to histopathology of 3D-CNN with 95% confidence intervals (CI) were 90.0%, 64.6% and 0.92 (CI 0.85-1.00), respectively. While dermatologists and augmented intelligence achieved the same sensitivity (90%) and comparable classification ROC-AUC (0.91 [CI 0.80-1.00], 0.88 [CI 0.77-1.00]) with 3D-CNN, their specificity was superior (92.3% and 86.2%, respectively). The 2D-CNN (sensitivity: 70%, specificity: 40%, ROC-AUC: 0.68 [CI 0.46-0.90]) was outperformed by 3D CNN and dermatologists. The 3D-CNN showed a higher correlation coefficient for repeated measurements of 246 lesions (R = 0.89) than the 2D-CNN (R = 0.79). The mean naevus count per patient varied significantly (gold standard: 210 lesions; 3D-CNN: 469; 2D-CNN: 1324; p < 0.0001). CONCLUSIONS: Our study emphasises the importance of validating the classification of CNNs in real life. The novel 3D-CNN device outperformed the 2D-CNN and achieved comparable sensitivity with dermatologists. The low specificity of CNNs and the lack of automated counting of TBP nevi currently limit the use of augmented intelligence in clinical practice.


Assuntos
Melanoma , Nevo Pigmentado , Nevo , Neoplasias Cutâneas , Humanos , Reprodutibilidade dos Testes , Estudos Prospectivos , Dermatologistas , Detecção Precoce de Câncer , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Melanoma/diagnóstico por imagem , Melanoma/patologia , Redes Neurais de Computação , Nevo/patologia , Nevo Pigmentado/diagnóstico por imagem , Fatores de Risco , Fotografação
19.
Front Oncol ; 13: 1174542, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37207151

RESUMO

Introduction: The worldwide incidence of melanoma has been increasing rapidly in recent decades with Switzerland having one of the highest rates in Europe. Ultraviolet (UV) radiation is one of the main risk factors for skin cancer. Our objective was to investigate UV protective behavior and melanoma awareness in a high-risk cohort for melanoma. Methods: In this prospective monocentric study, we assessed general melanoma awareness and UV protection habits in at-risk patients (≥100 nevi, ≥5 dysplastic nevi, known CDKN2A mutation, and/or positive family history) and melanoma patients using questionnaires. Results: Between 01/2021 and 03/ 2022, a total of 269 patients (53.5% at-risk patients, 46.5% melanoma patients) were included. We observed a significant trend toward using a higher sun protection factor (SPF) in melanoma patients compared with at-risk patients (SPF 50+: 48% [n=60] vs. 26% [n=37]; p=0.0016). Those with a college or university degree used a high SPF significantly more often than patients with lower education levels (p=0.0007). However, higher educational levels correlated with increased annual sun exposure (p=0.041). Neither a positive family history for melanoma, nor gender or Fitzpatrick skin type influenced sun protection behavior. An age of ≥ 50 years presented as a significant risk factor for melanoma development with an odd's ratio of 2.32. Study participation resulted in improved sun protection behavior with 51% reporting more frequent sunscreen use after study inclusion. Discussion: UV protection remains a critical factor in melanoma prevention. We suggest that melanoma awareness should continue to be raised through public skin cancer prevention campaigns with a particular focus on individuals with low levels of education.

20.
J Clin Med ; 11(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35329837

RESUMO

PURPOSE OF REVIEW: The purpose of this review is to summarize recent literature regarding the latest design modifications and biomechanical evolutions of reverse total shoulder arthroplasty and their impact on postoperative outcomes. RECENT FINDINGS: Over the past decade, worldwide implantation rates of reverse total shoulder arthroplasty have drastically increased for various shoulder pathologies. While Paul Grammont's design principles first published in 1985 for reverse total shoulder arthroplasty remained unchanged, several adjustments were made to address postoperative clinical and biomechanical challenges such as implant glenoid loosening, scapular notching, or limited range of motion in order to maximize functional outcomes and increase the longevity of reverse total shoulder arthroplasty. However, the adequate and stable fixation of prosthetic components can be challenging, especially in massive osteoarthritis with concomitant bone loss. To overcome such issues, surgical navigation and patient-specific instruments may be a viable tool to improve accurate prosthetic component positioning. Nevertheless, larger clinical series on the accuracy and possible complications of this novel technique are still missing.

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