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BACKGROUND: Angioleiomyomas are benign mesenchymal tumors usually located in the limbs, with anecdotal reports in the spine. We present an atypical case of an epidural spine angioleiomyoma presenting with compressive myelopathy symptoms. The diagnosis was suggested based on MRI findings, and subsequently confirmed histopathologically. RESULTS: This is the first known occurrence of pure spinal epidural angioleiomyoma as a source of compressive myelopathy. The imaging presentation, especially the 'dark reticular sign' on MRI, was crucial in suggesting the diagnosis despite the atypical location CONCLUSION: This report serves to raise awareness among clinicians and radiologists about including angioleiomyoma in differential diagnoses for spinal epidural lesions with indicative MRI features. The favorable outcome after surgical intervention underscores the necessity of swift and accurate diagnosis followed by appropriate treatment for such uncommon spinal tumors.
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Angiomioma , Imageamento por Ressonância Magnética , Compressão da Medula Espinal , Humanos , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/cirurgia , Angiomioma/diagnóstico por imagem , Angiomioma/cirurgia , Angiomioma/patologia , Angiomioma/complicações , Neoplasias Epidurais/diagnóstico por imagem , Neoplasias Epidurais/cirurgia , Neoplasias Epidurais/complicações , Neoplasias Epidurais/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento , Diagnóstico DiferencialRESUMO
OBJECTIVE: The aim of this work is to compare the effectiveness of blind and ultrasound-guided injection for Morton's neuroma (MN) to determine which is more appropriate as the initial procedure in conservative treatment. METHODS: This is an evaluator-blinded randomised trial. Of the 56 included patients, 27 were assigned to the blind group (A) and 29 to the ultrasound-guided group (B). Injection includes 1 ml of 2% mepivacaine and 40 mg of triamcinolone in each web space with MN. The included patients were assessed clinically by VAS score and the Manchester Foot Pain and Disability Score (MFPDS). The follow-up was performed at 15 days, 1 month, 45 days, 2 months, 3 months and 6 months after the initial injection. RESULTS: No differences in age or clinical measurements were found at presentation between group A and group B. At the follow-up, the ultrasound-guided group showed greater symptomatic relief at several stages of the follow-up: 45 days (VAS 3.0 ± 0.5 versus 5.5 ± 0.5, p = 0.001; MFPDS: 32.2 ± 1.8 versus 38.8 ± 2.0, p = 0.018), 2 months (VAS: 3.1 ± 0.5 versus 5.6 ± 0.5, p = 0.002; MFPDS: 31.5 ± 1.9 versus 38.5 ± 2.1, p = 0.020) and 3 months (VAS: 3.1 ± 0.4 versus 5.2 ± 0.6, p = 0.010; MFPDS: 31.2 ± 1.9 versus 37.7 ± 2.4, p = 0.047). CONCLUSION: Injection of MN under ultrasound guidance provides a statistically significant improvement at some stages of the follow-up (45 days, 2 and 3 months), compared with blind injection. KEY POINTS: ⢠Ultrasound-guided steroid injections in Morton's neuroma provide short-term pain relief to over 60% of the patients. ⢠Ultrasound-guided injections in Morton's neuroma lead to a higher percentage of short-term pain relief than blind injections. ⢠Ultrasound-guided injections in Morton's neuroma lead to a lower percentage of skin side effects than blind injections.
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Neuroma Intermetatársico/diagnóstico por imagem , Neuroma Intermetatársico/tratamento farmacológico , Adulto , Idoso , Anestésicos Locais/administração & dosagem , Anestésicos Locais/uso terapêutico , Quimioterapia Combinada , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Injeções Intralesionais , Masculino , Mepivacaína/administração & dosagem , Mepivacaína/uso terapêutico , Pessoa de Meia-Idade , Dor/tratamento farmacológico , Medição da Dor/métodos , Método Simples-Cego , Triancinolona/administração & dosagem , Triancinolona/uso terapêutico , Ultrassonografia de Intervenção/métodosRESUMO
The development of a foreign body granuloma from non-absorbable suture is a relatively uncommon condition, exceptional in the retroperitoneum of patients operated on for colorectal surgery. We report the case of a patient with a history of sigmoid neoplasm showing a retroperitoneal nodule on CT and high activity on PET, mimicking a tumor implant. Pathology found a foreign body granuloma. Foreign body granuloma from suture is a condition that may look identical to tumor relapse or metastatic disease on CT and PET scans, thus requiring pathology confirmation.
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Adenocarcinoma/complicações , Granuloma de Corpo Estranho/diagnóstico por imagem , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias do Colo Sigmoide/complicações , Suturas/efeitos adversos , Idoso , Diagnóstico Diferencial , Granuloma de Corpo Estranho/etiologia , Humanos , Masculino , Tomografia por Emissão de Pósitrons , Complicações Pós-Operatórias , Tomografia Computadorizada por Raios XAssuntos
Ovário/irrigação sanguínea , Dor Pélvica/etiologia , Varizes/etiologia , Malformações Vasculares/complicações , Veias/anormalidades , Adulto , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Dor Pélvica/diagnóstico , Dor Pélvica/fisiopatologia , Flebografia/métodos , Fluxo Sanguíneo Regional , Síndrome , Varizes/diagnóstico por imagem , Varizes/fisiopatologia , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/fisiopatologia , Veias/diagnóstico por imagem , Veias/fisiopatologiaRESUMO
Carbon fiber reinforced polymers (CFRPs) are interesting materials due to their excellent properties, such as their high strength-to-weight ratio, low thermal expansion, and high fatigue resistance. However, to meet the requirements for their assembly, the drilling processes involved should be optimized. Defects such as delamination, dimensional errors and poor internal surface finish can lead to the premature failure of parts when bolt-joined or rivet-connected. In addition, the characteristic anisotropy and heterogeneity of these materials, and the issues related to the temperature reached during drilling, make it difficult to obtain optimal cutting parameters or to achieve high material removal rates. This research focuses on the optimization of the CFRPs drilling process by means of experimental analysis-varying the feed and spindle speed-for two different types of commercial drills-a twist tool and a dagger tool. An automatic image processing methodology was developed for the evaluation of the dimensional accuracy and delamination of the holes. The optimization was carried out using a multi-objective regression technique based on the dimensional deviations, delamination and surface finish. The areas with favorable machining conditions have been delimited for both tools and the results indicate that the twist tool allows one to achieve more productive cutting conditions than the dagger tool, when the combination of low feeds and high spindle speeds are the conditions to be avoided.
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Titanium aluminides are one of the most promising materials in aeronautical and automotive applications. However, their low machinability makes the processing of these alloys quite difficult under sustainability conditions, specially without lubrication. The current study focuses on the turning process of the Ti48Al2Cr2Nb gamma titanium aluminide under dry conditions. As far as we are aware, dry cutting is the most sustainable feature, although it has not been traditionally applied on titanium aluminides due to the accelerated tool wear that the material promotes. The main novelty of this work consists of providing a simple solution for reducing the tool wear based on the inclination of the cutting insert, what is evaluated in terms of tool wear and tool life, cutting forces, cutting temperature, surface integrity of the machined part, as well as its microhardness and microstructural effects. The results shown here clearly point out a better performance of the machining process. This fact could be understood if we take into consideration that an increment of the clearance angle from 6.3° to 11.6° and 15° increases the tool life by five and six times, respectively, using efficient cutting speeds, whose values have increased by 50% with respect to the original cutting conditions. This improvement is explained according to the reduction in the cutting temperature and friction forces in the flank face of the tool. In addition, the use of uncoated carbide inserts may lead to a better behaviour than the coated ones, considering the results obtained for a PVD TiAlN + AlCr2O3 coated insert herein researched.
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Computed tomography (CT) and magnetic resonance imaging (MRI) have replaced conventional radiography in the study of many spinal conditions, it is essential to know when these techniques are indicated instead of or as complementary tests to radiography, which findings can be expected in different clinical settings, and their significance in the diagnosis of different spinal conditions. Proper use of CT and MRI in spinal disorders may facilitate diagnosis and management of spinal conditions. An adequate clinical approach, a good understanding of the pathological manifestations demonstrated by these imaging techniques and a comprehensive report based on a universally accepted nomenclature represent the indispensable tools to improve the diagnostic approach and the decision-making process in patients with spinal pain. Several guidelines are available to assist clinicians in ordering appropriate imaging techniques to achieve an accurate diagnosis and to ensure appropriate medical care that meets the efficacy and safety needs of patients. This article reviews the clinical indications of CT and MRI in different pathologic conditions affecting the spine, including congenital, traumatic, degenerative, inflammatory, infectious and tumor disorders, as well as their main imaging features. It is intended to be a pictorial guide to clinicians involved in the diagnosis and treatment of spinal disorders.
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Traditional flood lubrication in machining processes is considered an unsustainable technique. In this paper, the low initial lubrication (LIL) technique is analysed during turning of cupronickel 70/30 alloy, in terms of surface roughness. A tribological analysis has been developed on a pin-on-disk tribometer comparing different lubrication systems, obtaining comparative results of friction and tool wear. It has been found that the tool wear is 73% lower in comparison to flood lubrication. LIL technique shows the ability to reduce the friction coefficient compared to dry machining and leads to improve tool wear in comparison with flood lubrication. The surface integrity evaluation of machined parts finds that the LIL technique can improve the surface roughness under specific machining conditions.
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OBJECTIVE: To demonstrate the feasibility of percutaneous microwave ablation in desmoid fibromatosis with respect to tumor volume control and improvement in the quality of life. MATERIALS AND METHODS: Twelve microwave ablations were performed in 9 patients with a histological diagnosis of desmoid fibromatosis between January 2010 and January 2019. The study population included 6 female and 3 male, with an age range of 21-76 years (mean = 46.6 years; standard deviation [SD] = 19.3 years). The mean major axis of the tumors was 10.9 cm (SD = 5.2 cm) and mean lesion volume was 212.7 cm³ (SD = 213 cm³). Their anatomical distribution was as follows: 3 lesions in the thigh, 2 in the gluteus, 2 in the leg and 2 in the periscapular region. We evaluated the reduction in tumor volume and improvement in the quality of life based on the Eastern Cooperative Oncology Group (ECOG) scale. RESULTS: An average tumor volume reduction of 70.4% (SD = 24.9) was achieved, while the quality of life (ECOG scale) improved in 88.9% of patients. CONCLUSION: Percutaneous microwave ablation may potentially be a safe, effective, and promising technique for controlling tumor volume and improving the quality of life in patients with desmoid fibromatosis.
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Fibromatose Agressiva , Adulto , Idoso , Feminino , Fibromatose Agressiva/diagnóstico por imagem , Fibromatose Agressiva/cirurgia , Humanos , Masculino , Micro-Ondas/uso terapêutico , Pessoa de Meia-Idade , Qualidade de Vida , Ablação por Radiofrequência , Carga Tumoral , Adulto JovemRESUMO
Heat-assisted single point incremental forming or HA-SPIF has a great potential for producing one-piece batches of hard-to-form materials such as Ti6Al4V alloy for medical and aeronautical applications. One of the limitations of the process is the difficulty in achieving a reasonable surface finish, which makes essential the characterization of the tribological process in the tool-sheet contact. In fact, not much work can be found at this point in literature. In this research, a novel procedure for evaluating the adhesion on the tool surface is proposed and the influence of the temperature is determined. The surface finish of parts is analyzed, and the changes promoted by HA-SPIF appearing in the morphology of the external surface layer are characterized by SEM.
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Extraarticular synovial osteochondromatosis is a very rare benign disease whose aetiology may be primary or secondary to pre-existing pathology or after trauma. The diagnosis can be made with plain radiography and CT, and MRI is necessary to evaluate the non-mineralized soft tissue component and assess extension. It must be confirmed with a pathological study by biopsy or resection. There is up to a 5% chance of malignant transformation. The treatment of choice for the extensive extra-articular form is surgery by open resection. The case presented illustrates an atypical form of secondary extraarticular OCS with multiple involvement of the leg, ankle and foot.
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Condromatose Sinovial , Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/diagnóstico por imagem , Condromatose Sinovial/diagnóstico por imagem , Humanos , Perna (Membro) , RadiografiaRESUMO
PURPOSE: To present our experience on the implementation of radiofrequency thermal ablation (RFA) for the treatment of chondroblastoma. MATERIALS AND METHODS: This case series includes 12 patients (10 males) with chondroblastoma using RFA under CT guidance. Tumours were located in the humeral head (3), femoral head (2), distal femoral epiphysis (4), tibial epiphysis (2) and calcaneus (1). Tumour size ranged from 12 to 60 mm (median: 33 mm). According to tumour size and location, monopolar electrode's active tip ranged from 1 to 3 cm. Dry and perfused ablation mode was used to treat smaller (6) and larger (6) lesions, respectively. Cementation was also made in 5 cases. Technical success was considered if the tumour was treated according to the protocol and complete ablation was achieved. Clinical success was assessed according to a visual analogue scale. RESULTS: Technical success was achieved in 11 of 13 cases (83%) afters the first treatment. After a second treatment in the 2 failed cases, pain control was achieved in all cases eventually (100% of clinical success). Follow-up MRI demonstrated resolution of oedema in all cases, as well as a necrotic area extending beyond the outer edge of the lesion in all cases except one. Radiography or CT showed stability of the lesions, with increased sclerosis and no cortex collapse. In one case, a 4 cm shortening of the humerus was observed at the end of skeletal development (7 years after treatment). In another case, early hip osteoarthritis was developed (15 years after treatment). No other long-term complications were observed. CONCLUSION: Successful treatment of chondroblastoma can be achieved by RFA. Cementoplasty adds strength to the ablated bone in weight bearing areas. MRI hallmarks associated with clinical success were resolution of bone marrow edema, and area of necrosis extending beyond the tumour edge. Radiography and CT proved to be useful in demonstrating cortex integrity.
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Neoplasias Ósseas , Ablação por Cateter , Condroblastoma , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Condroblastoma/diagnóstico por imagem , Condroblastoma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Radiografia , Resultado do TratamentoRESUMO
Extraarticular synovial osteochondromatosis is a very rare benign disease whose aetiology may be primary or secondary to pre-existing pathology or after trauma. The diagnosis can be made with plain radiography and CT, and MRI is necessary to evaluate the non-mineralized soft tissue component and assess extension. It must be confirmed with a pathological study by biopsy or resection. There is up to a 5% chance of malignant transformation. The treatment of choice for the extensive extra-articular form is surgery by open resection. The case presented illustrates an atypical form of secondary extraarticular OCS with multiple involvement of the leg, ankle and foot.
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New technologies are offering progressively more effective alternatives to traditional ones. Additive Manufacturing (AM) is gaining importance in fields related to design, manufacturing, engineering and medicine, especially in applications which require complex geometries. Fused Deposition Modelling (FDM) is framed within AM as a technology in which, due to their layer-by-layer deposition, thermoplastic polymers are used for manufacturing parts with a high degree of accuracy and minimum material waste during the process. The traditional technology corresponding to FDM is Polymer Injection Moulding, in which polymeric pellets are injected by pressure into a mould using the required geometry. The increasing use of PA6 in Additive Manufacturing makes it necessary to study the possibility of replacing certain parts manufactured by injection moulding with those created using FDM. In this work, PA6 was selected due to its higher mechanical properties in comparison with PA12. Moreover, its higher melting point has been a limitation for 3D printing technology, and a further study of composites made of PA6 using 3D printing processes is needed. Nevertheless, analysis of the mechanical response of standardised samples and the influence of the manufacturing process on the polyamide's mechanical properties needs to be carried out. In this work, a comparative study between the two processes was conducted, and conclusions were drawn from an engineering perspective.
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Alkyldiamine-tethered derivatives of 2,6-diaminopurine, ethylenediamine-N9-propyl-2,6-diaminopurine, L1, and ethylenediamine-N9-ethyl-2,6-diaminopurine, L2, react with Pd(II) to give N3-coordinated complexes. However, the exact nature of the resulting complex is dependent on the reaction conditions. With PdCl(2)(MeCN)(2) in MeCN/H(2)O the expected [PdCl(N3-2,6-DAP-alkyl-en)](+) complex, 1, is formed with L1 chelating the metal center in a tridentate manner through the diamine function and N3 of the purine base. However, under the same conditions the shorter, ethyl-tethered, L2 gives a complex dication, 2, containing a tetradentate ligand forming simultaneously 5-, 6-, and 7-membered chelate rings. This resulting acetamidine, derived by addition to coordinated MeCN, appears to be the first such case involving the 2-amino group of a purine. The ethyl-analogue of 1, [PdCl(N3-2,6-DAP-Et-en)](+) 3, was prepared by reaction of L2 with K(2)PdCl(4) in aqueous media.
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2-Aminopurina/análogos & derivados , Quelantes/química , Compostos Organometálicos/química , Paládio/química , 2-Aminopurina/química , Cristalografia por Raios X , Ligantes , Modelos MolecularesRESUMO
The effect of the 2-amino group on metal ion binding at the N3-position of a purine base has been investigated using chelate-tethered derivatives. Reactions of diamine-tethered 2,6-diaminopurine (DAP) with divalent d-block metal ions Cu(II) and Cd(II) confirm that binding can occur, but this is much less prevalent than with adenine. In this regard DAP is similar to guanine where we have previously observed a general lack of N3-binding by divalent metal ions compared to adenine (e.g., Houlton et al., Angew. Chem., Int. Ed. 2000, 39, 2360; Chem.-Eur. J. 2000, 6, 4371). For the univalent d-block metals ions, Cu(I) and Ag(I), binding to adenine N3 is not observed in the solid state, as shown by reactions with dithioether-tethered adenine derivatives. Instead, depending on stoichiometry of the reaction, discrete (with metal/ligand ratio 1:2) or polymeric (with metal/ligand ratio 1:1) complexes were isolated and characterized by single crystal X-ray methods. In the former the nucleobases are pendant and involved in base-pair interactions, with both Watson-Crick...Watson-Crick and Hoogsteen...Hoogsteen type pairings present. For the coordination polymers a rather unexpected influence of the tether length on the site of nucleobase binding is found for bridging ligand binding modes involving the chelating diamine and the adeninyl group. Polymer chains derived with the shorter ethyl tether show binding at the N7 site of adeninyl, while binding at N1 is found in the longer propyl chain length.
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Cádmio/química , Cobre/química , DNA/química , Modelos Biológicos , Purinas/química , Sítios de Ligação , Cristalografia por Raios X , Ligantes , Estrutura Molecular , Prata/química , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Titanium is one of the most interesting materials in modern manufacturing thanks to its good mechanical properties and light weight. These features make it very attractive for use in the aeronautical and aerospace industries. Important alloys, such as Ti6Al4V, are extensively used. Nevertheless, titanium alloys present several problems in machining processes. Their machinability is poor, affected by low thermal conductivity, which generates very high cutting temperatures and thermal gradients in the cutting tool. Lubricants and cutting fluids have traditionally been used to solve this problem. However, this option is unsustainable as such lubricants represent a risk to the environment and to the health of the operator due to their different chemical components. Therefore, novel, sustainable and green lubrication techniques are necessary. Dry machining is the most sustainable option. Nevertheless, difficult-to-machine materials like titanium alloys cannot be machined under these conditions, leading to very high cutting temperatures and excessive tool wear. This study is intended to describe, analyse and review the non-traditional lubrication techniques developed in turning, drilling and milling processes since 2015, including minimum quantity of lubricant, cryogenic lubrication, minimum quantity of cooling lubrication or high-pressure coolant. The aim is to provide a general overview of the recent advances in each technique for the main machining processes.
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This extended review tries to cover the imaging findings of the wide range of shoulder injuries secondary to shoulder joint instability. Usefulness of the different imaging methods is stressed, including radiography, computed tomography (CT) and magnetic resonance. The main topics to be covered include traumatic, atraumatic and minor instability syndromes. Radiography may show bone abnormalities associated to instability, including developmental and post-traumatic changes. CT is the best technique depicting and quantifying skeletal changes. MR-arthrography is the main tool in diagnosing the shoulder instability injuries.
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This article describes different types of vertebral fractures that affect the thoracolumbar spine and the most relevant contributions of the different classification systems to vertebral fracture management. The vertebral fractures types are based on the three columns model of Denis that includes compression, burst, flexion-distraction and fracture-dislocation types. The most recent classifications systems of these types of fractures are reviewed, including the Thoracolumbar Injury Classification and Severity score (TLICS) and the Arbeitsgemeinschaft für Osteosynthesefragen Spine Thoracolumbar Injury Classification and Severity score (AOSpine-TLICS). Correct classification requires a quantitative imaging approach in which several measurements determine TLICS or AOSpine-TLICS grade. If the TLICS score is greater than 4, or the AOSpine-TLICS is greater than 5, surgical management is indicated. In this review, the most important imaging findings and measurements on radiography, multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) are described. These include degree of vertebral wedging and percentage of vertebral height loss in compression fractures, degree of interpedicular distance widening and spinal canal stenosis in burst fractures, and the degree of vertebral translation or interspinous widening in more severe fractures types, such as flexion-distraction and fracture-dislocation. These findings and measurements are illustrated with schemes and cases of our archives in a didactic way.
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Hip pain can have multiple causes, including intra-articular, juxta-articular, and referred pain, mainly from spine or sacroiliac joints. In this review, we discuss the causes of intra-articular hip pain from childhood to adulthood and the role of the appropriate imaging techniques according to clinical suspicion and age of the patient. Stress is put on the findings of radiographs, currently considered the first imaging technique, not only in older people with degenerative disease but also in young people without osteoarthritis. In this case plain radiography allows categorization of the hip as normal or dysplastic or with impingement signs, pincer, cam, or a combination of both.