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OBJECTIVE: To prospectively assess the early changes in the quadriceps and patellar tendons before and after total knee arthroplasty using ultrasound, shear wave elastography, and X-rays. MATERIALS AND METHODS: Radiographs, ultrasound, and shear wave elastography were performed on 23 patients (16 women; aged 51-85, mean 66 ± 9 years) before and after surgery at 6 weeks and on 11 patients at 3 months. Patellar position and patellar tendon lengths were evaluated by radiography; joint effusion or synovitis, quadriceps and patellar tendon lengths, and thicknesses, echogenicity, vascularity, and stiffness were assessed with ultrasound and shear wave elastography. RESULTS: In the early postoperative period, 87% of the patients had joint effusion, and 43% had signs of synovitis. There was a significant thickening of the quadriceps tendon in 51.5% (p < .0001) and of the patellar tendon in 93.8% (p < .0001) of patients with a significant shortening of the patellar tendon in 7.8% (p < .0001). A hypoechoic defect on the medial aspect of the quadriceps tendon was found in 87% of the patients. There was a significant increase in Young's modulus in the quadriceps tendon (p = .0006) but not in the patellar tendon. CONCLUSION: The following should not be considered to be pathological findings at early postoperative imaging: joint effusion, synovitis, increasing of stiffness and thickening of quadriceps tendons by more than 50%, thickening of patellar tendon by more than 90%, focal defect through the medial aspect of the quadriceps tendon, and shortening of the patellar tendon by 8%.
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Artroplastia do Joelho , Ligamento Patelar , Feminino , Humanos , Patela/diagnóstico por imagem , Ligamento Patelar/diagnóstico por imagem , Período Pós-Operatório , Tendões/diagnóstico por imagem , Tendões/cirurgia , UltrassonografiaRESUMO
Fetuses at the extremes of growth abnormalities carry a risk of perinatal morbidity and death. Their identification traditionally is done by 2-dimensional ultrasound imaging, the performance of which is not always optimal. Magnetic resonance imaging superbly depicts fetal anatomy and anomalies and has contributed largely to the evaluation of high-risk pregnancies. In 1994, magnetic resonance imaging was introduced for the estimation of fetal weight, which is done by measuring the fetal body volume and converting it through a formula to fetal weight. Approximately 10 studies have shown that magnetic resonance imaging is more accurate than 2-dimensional ultrasound imaging in the estimation of fetal weight. Yet, despite its promise, the magnetic resonance imaging technique currently is not implemented clinically. Over the last 5 years, this technique has evolved quite rapidly. Here, we review the literature data, provide details of the various measurement techniques and formulas, consider the application of the magnetic resonance imaging technique in specific populations such as patients with diabetes mellitus and twin pregnancies, and conclude with what we believe could be the future perspectives and clinical application of this challenging technique. The estimation of fetal weight by ultrasound imaging is based mainly on an algorithm that takes into account the measurement of biparietal diameter, head circumference, abdominal circumference, and femur length. The estimation of fetal weight by magnetic resonance imaging is based on one of the 2 formulas: (1) magnetic resonance imaging-the estimation of fetal weight (in kilograms)=1.031×fetal body volume (in liters)+0.12 or (2) magnetic resonance imaging-the estimation of fetal weight (in grams)=1.2083×fetal body volume (in milliliters)Ë0.9815. Comparison of these 2 formulas for the detection of large-for-gestational age neonates showed similar performance for preterm (P=.479) and for term fetuses (P=1.000). Literature data show that the estimation of fetal weight with magnetic resonance imaging carries a mean or median relative error of 2.6 up to 3.7% when measurements were performed at <1 week from delivery; whereas for the same fetuses, the relative error at 2-dimensional ultrasound imaging varied between 6.3% and 11.4%. Further, in a series of 270 fetuses who were evaluated within 48 hours from birth and for a fixed false-positive rate of 10%, magnetic resonance imaging detected 98% of large-for-gestational age neonates (≥95th percentile for gestation) compared with 67% with ultrasound imaging estimates. For the same series, magnetic resonance imaging applied to the detection of small-for-gestational age neonates ≤10th percentile for gestation, for a fixed 10% false-positive rate, reached a detection rate of 100%, compared with only 78% for ultrasound imaging. Planimetric measurement has been 1 of the main limitations of magnetic resonance imaging for the estimation of fetal weight. Software programs that allow semiautomatic segmentation of the fetus are available from imaging manufacturers or are self-developed. We have shown that all of them perform equally well for the prediction of large-for-gestational age neonates, with the advantage of the semiautomatic methods being less time-consuming. Although many challenges remain for this technique to be generalized, a 2-step strategy after the selection of a group who are at high risk of the extremes of growth abnormalities is the most likely scenario. Results of ongoing studies are awaited (ClinicalTrials.gov Identifier # NCT02713568).
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Peso ao Nascer , Peso Fetal , Feto/diagnóstico por imagem , Imageamento por Ressonância Magnética , Diabetes Gestacional , Feminino , Humanos , Imageamento Tridimensional , Conceitos Matemáticos , Gravidez , Gravidez de Gêmeos , Software , Ultrassonografia Pré-NatalRESUMO
OBJECTIVE: The aim of this study was to apply a semi-automated calculation method of fetal body volume and, thus, of magnetic resonance-estimated fetal weight (MR-EFW) prior to planned delivery and to evaluate whether the technique of measurement could be simplified while remaining accurate. METHODS: MR-EFW was calculated using a semi-automated method at 38.6 weeks of gestation in 36 patients and compared to the picture archiving and communication system (PACS). Per patient, 8 sequences were acquired with a slice thickness of 4-8 mm and an intersection gap of 0, 4, 8, 12, 16, or 20 mm. The median absolute relative errors for MR-EFW and the time of planimetric measurements were calculated for all 8 sequences and for each method (assisted vs. PACS), and the difference between the methods was calculated. RESULTS: The median delivery weight was 3,280 g. The overall median relative error for all 288 MR-EFW calculations was 2.4% using the semi-automated method and 2.2% for the PACS method. Measurements did not differ between the 8 sequences using the assisted method (p = 0.313) or the PACS (p = 0.118), while the time of planimetric measurement decreased significantly with a larger gap (p < 0.001) and in the assisted method compared to the PACS method (p < 0.01). CONCLUSION: Our simplified MR-EFW measurement showed a dramatic decrease in time of planimetric measurement without a decrease in the accuracy of weight estimates.
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Peso Fetal , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Software , Adulto , Feminino , Idade Gestacional , Humanos , Gravidez , Terceiro Trimestre da GravidezRESUMO
INTRODUCTION: Soft tissue sarcomas (STSs) are rare malignancies. Pre-therapeutic tumour grading and assessment are crucial in making treatment decisions. Radiomics is a high-throughput method for analysing imaging data, providing quantitative information beyond expert assessment. This review highlights the role of radiomic texture analysis in STSs evaluation. MATERIALS AND METHODS: We conducted a systematic review according to the Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search was conducted in PubMed/MEDLINE and Scopus using the search terms: 'radiomics [All Fields] AND ("soft tissue sarcoma" [All Fields] OR "soft tissue sarcomas" [All Fields])'. Only original articles, referring to humans, were included. RESULTS: A preliminary search conducted on PubMed/MEDLINE and Scopus provided 74 and 93 studies respectively. Based on the previously described criteria, 49 papers were selected, with a publication range from July 2015 to June 2023. The main domains of interest were risk stratification, histological grading prediction, technical feasibility/reproductive aspects, treatment response. CONCLUSIONS: With an increasing interest over the last years, the use of radiomics appears to have potential for assessing STSs from initial diagnosis to predicting treatment response. However, additional and extensive research is necessary to validate the effectiveness of radiomics parameters and to integrate them into a comprehensive decision support system.
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Gout is a common disease, and its prevalence is increasing. After several years of untreated gout, in very rare cases tophi may cause a spontaneous fracture. This type of fracture may be difficult to distinguish from others, especially when gout is not yet diagnosed. We present a case of a pathological fracture caused by tophus in a young man, which led to the diagnosis of gout.
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PURPOSE: This study aims to evaluate the clinical scenarios addressed by the EURO-2000 guidelines and the ACR appropriateness criteria for referring children to MRI and assessing the referring physician compliance with both guidelines. METHODS: In January 2022, clinical scenarios reported in the last 1000 consecutive MRI requests for children (0-16 years) in one university children's hospital and two general university hospitals in Belgium, Europe, were retrospectively matched to the EURO-2000 guidelines and ACR appropriateness criteria. The number of clinical scenarios addressed and the justification for MRI referral were independently assessed for both guidelines. Pooled data from the three centers were evaluated and then analyzed by center, body area and prescriber using McNemar's test for paired proportions and χ2-tests unpaired proportions. RESULTS: After excluding incomplete or missing MRI requests, 2932 of 3000 requests were included in the analysis. Overall, out of 2932 clinical scenarios, 1229 (37.99%) were addressed by EURO-2000 and 1081 (36.37%) were addressed by the ACR appropriateness criteria (McNemar test, p = 0.12). The proportions of clinical scenarios covered by the two guidelines were statistically similar when comparing centers, but varied across body regions (p < 0.001) and referring physician specialty (p between 0.75 and 0.001). EURO-2000 guidelines provided better coverage for head and spine (p < 0.05), while the ACR appropriateness criteria provided broader coverage for abdomen, pelvis, and musculoskeletal system (p < 0.0001). For addressed clinical scenarios, prescriber compliance for both guidelines was excellent with > 94% of justified MRI examinations in all the centers. CONCLUSIONS: Both the EURO-2000 guidelines and the ACR appropriateness criteria did not address two-thirds of clinical scenarios in children. Head and neck, chest and abdominal-pelvic examinations are the anatomic regions which should receive a specific attention for the future implementation of evidence-based clinical decision support tools for all referring specialists.
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Imageamento por Ressonância Magnética , Radiologia , Criança , Humanos , Abdome , Exame Físico , Estudos Retrospectivos , Sociedades Médicas , Estados Unidos , Recém-Nascido , Lactente , Pré-Escolar , AdolescenteRESUMO
INTRODUCTION: This study aimed to evaluate whether radiomic features extracted solely from the edema of soft tissue sarcomas (STS) could predict the occurrence of lung metastasis in comparison with features extracted solely from the tumoral mass. MATERIALS AND METHODS: We retrospectively analyzed magnetic resonance imaging (MRI) scans of 32 STSs, including 14 with lung metastasis and 18 without. A segmentation of the tumor mass and edema was assessed for each MRI examination. A total of 107 radiomic features were extracted for each mass segmentation and 107 radiomic features for each edema segmentation. A two-step feature selection process was applied. Two predictive features for the development of lung metastasis were selected from the mass-related features, as well as two predictive features from the edema-related features. Two Random Forest models were created based on these selected features; 100 random subsampling runs were performed. Key performance metrics, including accuracy and area under the ROC curve (AUC), were calculated, and the resulting accuracies were compared. RESULTS: The model based on mass-related features achieved a median accuracy of 0.83 and a median AUC of 0.88, while the model based on edema-related features achieved a median accuracy of 0.75 and a median AUC of 0.79. A statistical analysis comparing the accuracies of the two models revealed no significant difference. CONCLUSION: Both models showed promise in predicting the occurrence of lung metastasis in soft tissue sarcomas. These findings suggest that radiomic analysis of edema features can provide valuable insights into the prediction of lung metastasis in soft tissue sarcomas.
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The aim of this in vitro study was to evaluate thermal effects on implant surfaces using a 445 nm diode laser (Eltech K-Laser Srl, Treviso, Italy) with different power settings and irradiation modalities. Fifteen new implants (Straumann, Basel, Switzerland) were irradiated to evaluate surface alteration. Each implant was divided into two zones: the anterior and posterior areas. The anterior coronal areas were irradiated with a distance of 1 mm between the optical fiber and the implant; the anterior apical ones were irradiated with the fiber in contact with the implant. Instead, the posterior surfaces of all of the implants were not irradiated and used as control surfaces. The protocol comprised two cycles of laser irradiation, lasting 30 s each, with a one-minute pause between them. Different power settings were tested: a 0.5 W pulsed beam (T-on 25 ms; T-off 25 ms), a 2 W continuous beam and a 3 W continuous beam. Lastly, through a scanning electron microscopy (SEM) analysis, dental implants' surfaces were evaluated to investigate surface alterations. No surface alterations were detected using a 0.5 W laser beam with a pulsed mode at a distance of 1 mm. Using powers of irradiation of 2 W and 3 W with a continuous mode at 1 mm from the implant caused damage on the titanium surfaces. After the irradiation protocol was changed to using the fiber in contact with the implant, the surface alterations increased highly compared to the non-contact irradiation modality. The SEM results suggest that a power of irradiation of 0.5 W with a pulsed laser light emission mode, using an inactivated optical fiber placed 1 mm away from the implant, could be used in the treatment of peri-implantitis, since no implant surface alterations were detected.
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Osteosarcoma is an aggressive primary malignant bone tumor with frequent local or metastatic recurrence after surgery. Lungs are the most common site of metastasis. Although the majority of relapses will occur within five years of the initial diagnosis of osteosarcoma, lung metastases may appear a long time after initial presentation. This mechanism is known as late-relapse metastasis, in which dormant metastatic cells undergo reactivation and give rise to metastatic outgrowths. We report a case of a 29-year-old woman diagnosed with osteosarcoma of the left distal tibia. Chest CT performed at the initial presentation showed no metastasis. The patient underwent two cycles of neoadjuvant chemotherapy prior to surgery. Routine follow-up chest CT revealed a lung nodule five years later. A sudden increase in the size of the lung nodule was observed two years later. Histopathological analysis of the lung nodule confirmed osteosarcoma lung metastasis. A better understanding of the various types of aspects and atypical behaviors of osteosarcoma metastases could have a significant impact on the prognosis of the patients.
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Bone granulomas (BGs) due to foreign bodies are a rare condition, especially in children, with only few cases reported in literature. As foreign bodies are not always visible on imaging, BGs can mimic bone tumors. We hereby present a case of a six-year-old boy with histopathologically confirmed BG of his right hand fifth finger due to intraosseous foreign bodies, along with imaging work-up.
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PURPOSE: The purpose of this study is to evaluate the performance of estimating fetal weight (EFW) using magnetic resonance (MR) imaging as compared with two-dimensional (2D) ultrasound (US) in the prediction of small-for-gestational age neonates (SGA). MATERIALS AND METHODS: Written informed consent was obtained for this Ethical Committee approved study. Between March 2011 and May 2016, women with singleton pregnancies underwent US-EFW and MR-EFW within 48 h before delivery. US-EFW was based on Hadlock et al. and MR-EFW on the formula described by Backer et al. after planimetric measurement of the fetal body volume (FBV). Our outcome measure was performance in prediction of small-for-gestational age neonates by MR imaging versus US-EFW, using receiver-operating characteristic (ROC) curves. RESULTS: Two hundred and seventy women were included in the study with 18 newborns (6.7%) of birthweight ≤10th, 12 (4.5%) ≤ 5th and 7 (2.6%) ≤ 3rd centile. The area under the ROC curve for prediction of birthweight ≤10th centile by prenatal MR imaging was significantly better than by US (difference between the AUROC = 0.060, p = .01; standard error = 0.023). Similarly, the area under the ROC curve for prediction of birthweight ≤5th centile by prenatal MR imaging was significantly better than by US (difference between the AUROC = 0.019, p = .03; standard error = 0.009). Finally, there was no significant difference between the areas under the ROC curve for the prediction of birthweight ≤3rd centile between the two imaging modalities (difference between the AUROC = 0.021, p = .13; standard error = 0.014). CONCLUSION: MR-EFW performed immediately prior to delivery predicts SGA neonates significantly better than US-EFW.