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1.
Artigo em Inglês | MEDLINE | ID: mdl-39109775

RESUMO

The urinary volume and residual urine volume are pieces of information that can provide relevant clinical data for dogs and cats, especially those hospitalized. Thus, the present study aimed to evaluate mathematical formulas described in human and veterinary literature to estimate urinary volume in dogs and experimental models. For this purpose, nine male dog cadavers and twelve experimental models were used to evaluate residual volume, small, medium, and large, using three different formulas. Data were obtained by three different examiners: two ultrasonographers and one nonultrasonographer. Each examiner recorded three longitudinal and transverse images, obtaining measurements of width, length, and height at each proposed volume. The measurements were then averaged, and the result was added to the formulas, thus estimating urinary volume. All three formulas achieved higher accuracy in estimating smaller volumes, with a gradual decrease as urinary volume increased. The error of all formulas was less than 10%, even when compared with evaluations in experimental models and dogs. There was variation in estimation between ultrasonographers and nonultrasonographer examiners; however, this variation was low, allowing for the assertion that both can apply the technique. Thus, it is concluded that estimating urinary bladder volume using mathematical formulas and 2D ultrasound is accurate and, therefore, an alternative and viable option for evaluating the urinary tract.

2.
Front Vet Sci ; 11: 1322871, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988978

RESUMO

Epidural anesthesia in dogs is a locoregional anesthesia technique used in veterinary medicine, becoming an important integrated application in the anesthetic protocol to provide safer and more effective analgesia to patients. For this, professionals must adhere to rigorous guidelines and possess technical skills. In this context, in veterinary education, the development of practical clinical skills represents a crucial aspect in the training of these professionals. However, traditional teaching methods have proven insufficient to ensure a consistent level of competence among recent graduates. The introduction of non-animal alternatives for educational purposes has contributed to the development of simulation-based teaching, an innovative and accessible field capable of enhancing pre-clinical proficiency in students and reducing the use of live animals and cadavers. Despite its application in various areas of veterinary education, there are no conclusive results regarding the development of accessible simulators capable of effectively enhancing training in epidural anesthesia in dogs. Therefore, this article represents a pioneering study aimed at sharing a method for creating SimuVet, a realistic simulator for training epidural anesthesia in dogs. The simulator was fully developed by veterinary researchers with limited experience in 3D printing and, after preliminary analysis, demonstrated excellent performance and ultrasonographic anatomy. Future work will focus on the formal validation of this simulator with the aim of improving the teaching and learning process for students and experts in performing epidural anesthesia in companion animals.

3.
Adv Rehabil Sci Pract ; 13: 27536351241261023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39045264

RESUMO

Introduction: Estimates of the worldwide increase in amputees raises the awareness to solve long-standing problems. Understanding the functional brain modifications after a lower limb amputation (LLA) is one of the first steps towards proposing new rehabilitation approaches. Functional modifications in the central nervous system due the amputation could be involved in prosthesis use failures and Phantom Limb Pain (PLP), increasing costs and overwhelming the health services. Objective: This study analyses orphan primary motor area (M1-Orphan) hemodynamic and metabolic behaviour, which previously controlled the limb that was amputated, in comparison with the M1-Preserved, responsible for the intact limb (IL) during phantom limb imagery moving during Mirror Therapy (MT), compared to Isolated Intact Limb Movement Task (I-ILMT). Methodology: A case-control study with unilateral traumatic LLA with moderate PLP who measured [oxy-Hb] and [deoxy-Hb] in the M1 area by Functional Near InfraredSpectroscopy (fNIRS) during the real (I-ILMT) and MT task. Results: Sixty-five patients, with 67.69% of men, young (40.32 ± 12.91), 65.63% amputated due motorcycle accidents, 4.71 ± 7.38 years ago, predominantly above the knee (57.14%). The M1 activation in the orphan cortex did not differ from the activation in the intact cortex during MT (P > .05). Conclusion: The perception of the Phantom limb moving or intact limb moving is metabolically equivalent in M1, even in the absence of a limb. In other words, the amputation does not alter the brain metabolism in control of phantom movement.

4.
Pain Med ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38964349

RESUMO

OBJECTIVE: To explore the relationship between sociodemographic, clinical, and neurophysiological variables and health-related quality of life (HR-QOL) of patients with phantom limb pain. METHODS: This is a cross-sectional analysis of a previous clinical trial. Univariate and multivariate linear and logistic regression analyses were used to model the predictors of HR-QOL. We utilized a sequential modeling approach with increasing adjustment levels, controlling for age and sex, and other relevant clinical variables (time since amputation, level of amputation, and pain). HR-QOL was assessed by the SF-36 Health Survey and its eight subdomains. RESULTS: We analyzed baseline data from 92 patients with lower-limb amputations. They were mostly male (63%), 45.2 ± 15.6 years, with a mean time since amputation of 82.7 ± 122.4 months, and an overall SF-36 score of 55.9 ± 21.5. We found an association between intracortical facilitation in the affected hemisphere (ICF), gabapentin usage, and HR-QOL. ICF is a predictor of better HRQOL, whereas gabapentin usage was associated with a poorer HR-QOL, with the main model explaining 13.4% of the variance in the outcome. For the SF-36 subdomains, ICF was also a positive predictor for social functioning, bodily pain, and vitality, while medication usage was associated with lower scores in mental health, general health perception, bodily pain, and vitality. CONCLUSION: We found firsthand two new independent predictors of HR-QOL in individuals with PLP, namely, the neurophysiological metric ICF and gabapentin usage. These results highlight the role of the motor cortex excitability in the HR-QOL and stress the need for treatments that favor the neuroplastic adaptation after amputation, for which ICF may be used as a possible marker.

5.
Biomed Phys Eng Express ; 10(4)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38697045

RESUMO

Whole-body counters (WBC) are used in internal dosimetry forin vivomonitoring in radiation protection. The calibration processes of a WBC set-up include the measurement of a physical phantom filled with a certificate radioactive source that usually is referred to a standard set of individuals determined by the International Commission on Radiological Protection (ICRP). The aim of this study was to develop an anthropomorphic and anthropometric female physical phantom for the calibration of the WBC systems. The reference female computational phantom of the ICRP, now called RFPID (Reference Female Phantom for Internal Dosimetry) was printed using PLA filament and with an empty interior. The goal is to use the RFPID to reduce the uncertainties associated within vivomonitoring system. The images which generated the phantom were manipulated using ImageJ®, Amide®, GIMP®and the 3D Slicer®software. RFPID was split into several parts and printed using a 3D printer in order to print the whole-body phantom. The newly printed physical phantom RFPID was successfully fabricated, and it is suitable to mimic human tissue, anatomically similar to a human body i.e., size, shape, material composition, and density.


Assuntos
Imagens de Fantasmas , Impressão Tridimensional , Contagem Corporal Total , Humanos , Feminino , Contagem Corporal Total/métodos , Calibragem , Proteção Radiológica/métodos , Proteção Radiológica/instrumentação , Radiometria/métodos , Radiometria/instrumentação , Antropometria
6.
World J Methodol ; 14(1): 88850, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38577207

RESUMO

BACKGROUND: The authors describe a technique for building an alternative jawbone phantom using dental gypsum and rice for research and dental radiology instruction. AIM: To investigate the potential of an alternative phantom to simulate the trabecular bone aspect of the human maxilla in periapical radiographs. METHODS: Half-maxillary phantoms built from gypsum-ground rice were exposed to X-rays, and the resulting images (experimental group) were compared to standardized radiographic images produced from dry human maxillary bone (control group) (n = 7). The images were blindly assessed according to strict criteria by three examiners for the usual trabecular aspects of the surrounding bone, and significant differences between groups and in assessment reliability were compared using Fisher's exact and kappa tests (α = 0.05). RESULTS: The differences in the trabecular aspects between groups were not statistically significant. In addition, interobserver agreement among observers was 0.43 and 0.51 for the control and experimental groups, respectively, whereas intraobserver agreement was 0.71 and 0.73, respectively. CONCLUSION: The tested phantom seemed to demonstrate potential for trabecular bone image simulation on maxillary periapical radiographs.

7.
Rev. mex. anestesiol ; 47(1): 52-56, ene.-mar. 2024. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1576566

RESUMO

Resumen: El liposarcoma pleomórfico es una neoformación de tejidos blandos, que afecta principalmente las extremidades. Los pacientes que los presentan son candidatos a resección amplia o incluso amputación del miembro afectado. Como parte de una técnica anestésica integral y multimodal, destaca la utilización de bloqueos ecoguiados que disminuirán los requerimientos de opioides, teniendo un impacto importante en la preservación de la inmunidad del paciente oncológico, lo que le permitirá aumentar la tasa de supervivencia y su período libre de enfermedad; adicionando además un alfa 2 agonista, el cual nos brinda una adecuada analgesia postoperatoria, y realizando los bloqueos previos a la amputación, tenemos mayor tasa de éxito en la prevención del dolor y síndrome de miembro fantasma.


Abstract: Pleomorphic liposarcoma is a neoformation, which mainly affects the extremities. Being the patient candidate to perform a wide resection or even amputation of the affected limb. As part of a multimodal anesthetic technique, the use of ultrasound-guided blocks are useful, reducing opioid requirements, having an important impact on the preservation of the cancer patient's immunity, also adding an alpha 2 agonist, which provides adequate postoperative analgesia, and performing the blocks prior to amputation, we have a higher success rate in the prevention of pain and phantom limb syndrome.

8.
Neurophysiol Clin ; 54(1): 102939, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38382136

RESUMO

BACKGROUND: Phantom pain limb (PLP) has gained more attention due to the large number of people with amputations around the world and growing knowledge of the pain process, although its mechanisms are not completely understood. OBJECTIVES: The aim of this study was to understand, in patients with amputations, the association between PLP and residual limb pain (RLP), and the brain metabolic response in cortical motor circuits, using functional near-infrared spectroscopy (fNIRS). METHODS: Sixty participants were recruited from the rehabilitation program in São Paulo, Brazil. Included patients were aged over 18 years, with traumatic unilateral lower-limb amputation, with PLP for at least 3 months after full recovery from amputation surgery. PLP and RLP levels were measured using visual analogue scales. fNIRS was performed during motor execution and motor mirror tasks for 20 s. In order to highlight possible variables related to variation in pain measures, univariate linear regression analyses were performed for both experimental conditions, resulting in four fNIRS variables (two hemispheres x two experimental conditions). Later, in order to test the topographic specificity of the models, eight multivariate regression analyses were performed (two pain scales x two experimental conditions x two hemispheres), including the primary motor cortex (PMC) related channel as an independent variable as well as five other channels related to the premotor area, supplementary area, and somatosensory cortex. All models were controlled for age, sex, ethnicity, and education. RESULTS: We found that: i) there is an asymmetric metabolic activation during motor execution and mirror task between hemispheres (with a predominance that is ipsilateral to the amputated limb), ii) increased metabolic response in the PMC ipsilateral to the amputation is associated with increased PLP (during both experimental tasks), while increased metabolic response in the contralateral PMC is associated with increased RLP (during the mirror motor task only); ii) increased metabolic activity of the ipsilateral premotor region is associated with increased PLP during the motor mirror task; iii) RLP was only associated with higher metabolic activity in the contralateral PMC and lower metabolic activity in the ipsilateral inferior frontal region during motor mirror task, but PLP was associated with higher metabolic activity during both tasks. CONCLUSION: These results suggest there is both task and region specificity for the association between the brain metabolic response and the two different types of post-amputation pain. The metabolic predominance that is ipsilateral to the amputated limb during both tasks was associated with higher levels of PLP, suggesting a cortical motor network activity imbalance due to potential interhemispheric compensatory mechanisms. The present work contributes to the understanding of the underlying topographical patterns in the motor-related circuits associated with pain after amputations.


Assuntos
Córtex Motor , Membro Fantasma , Humanos , Adulto , Pessoa de Meia-Idade , Espectroscopia de Luz Próxima ao Infravermelho , Brasil , Amputação Cirúrgica , Membro Fantasma/reabilitação , Extremidade Inferior
9.
Eur J Breast Health ; 20(1): 64-70, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38187105

RESUMO

Objective: The aim of this work was to describe a technique for building low-cost simulators for training in minimally invasive breast procedures guided by ultrasound (US) and stereotactic mammography (MMG), focusing mainly on training medical professionals studying related areas. Materials and Methods: Low-cost phantoms were developed using organic structures that mimic breast tissue, such as chicken breast and eggplant, and materials that simulate breast lesions. A step-by-step description of the preparation and use of these simulators was made, enabling the reproducibility of the technique by the physicians in training themselves. Results: The low-cost phantoms showed a high degree of echogenic and radiological similarity with human breast tissue, allowing adequate training in minimally invasive procedures. Conclusion: It was possible to build low-cost phantoms that allow training in US- and stereotactic MMG-guided minimally invasive breast procedures.

10.
Vasc Endovascular Surg ; 58(3): 343-349, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37944002

RESUMO

BACKGROUND: When treating aortic aneurysm patients with complex anatomical features, preprocedural planning aided by 3D-printed models offers valuable insights for endovascular intervention. This study highlights the use of stereolithographic (SLA) 3D printing to fabricate a phantom of a challenging aortic arch aneurysm with a complex neck anatomy. CLINICAL CASE: A 75-year-old female presented with a 58 mm descending thoracic aortic aneurysm (TAA) extending to the distal arch, involving the left subclavian artery (LSA) and the left common carotid artery (LCCA). The computed tomography (CT) scans underwent scrutiny by radiology and vascular teams. Nevertheless, the precise spatial relationships of the ostial origins proved to be challenging to ascertain. To address this, a patient-specific phantom of the aortic arch was fabricated utilizing an SLA printer and a biomedical resin. The thoracic endovascular aortic repair (TEVAR) procedure was simulated using fluoroscopy on the phantom to enhance procedural preparedness. Subsequently, the patient underwent a right carotid-left carotid bypass and a right carotid-left subclavian bypass. After a 24-hour interval, the patient underwent the TEVAR procedure, during which a 37 mm × 150 mm stent graft (CTAG, WL Gore and Associates, Flagstaff, AZ, USA) and a 40 mm × 200 mm stent graft (CTAG, WL Gore and Associates, Flagstaff, AZ, USA) were deployed, effectively covering the LSA and LCCA. Notably, the aneurysm exhibited complete sealing, with no indications of endoleaks or graft infoldings. At the 12-month follow-up, the patient remains in good health, with no evidence of endoleaks or any other surgery-related complication. CONCLUSION: This report showcases the successful use of a 3D-printed endovascular phantom in guiding the decision-making process during the preparation for a TEVAR procedure. The simulation played a pivotal role in selecting the appropriate stent graft, ensuring an intervention protocol optimized based on the patient-specific anatomy.


Assuntos
Aneurisma , Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Feminino , Humanos , Idoso , Correção Endovascular de Aneurisma , Prótese Vascular/efeitos adversos , Stents/efeitos adversos , Endoleak/etiologia , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Resultado do Tratamento , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/complicações , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma/cirurgia , Estudos Retrospectivos
11.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;82(1): s00441779051, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1533837

RESUMO

Abstract Background Phantom limb pain (PLP) occurs after amputations and can persist in a chronic and debilitating way. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neuromodulation method capable of influencing brain function and modulating cortical excitability. Its effectiveness in treating chronic pain is promising. Objective To evaluate the evidence on the efficacy and safety of using rTMS in the treatment of PLP, observing the stimulation parameters used, side effects, and benefits of the therapy. Methods This is a systematic review of scientific articles published in national and international literature using electronic platforms. Results Two hundred and fifty two articles were identified. Two hundred and forty six publications were removed because they were duplicated or met the exclusion criteria. After selection, six studies were reviewed, those being two randomized clinical trials and four case reports. All evaluated studies indicated some degree of benefit of rTMS to relieve painful symptoms, even temporarily. Pain perception was lower at the end of treatment when compared to the period prior to the sessions and remained during patient follow-up. There was no standardization of the stimulation parameters used. There were no reports of serious adverse events. The effects of long-term therapy have not been evaluated. Conclusion There are some benefits, even if temporary, in the use of rTMS to relieve painful symptoms in PLP. High-frequency stimulation at M1 demonstrated a significant analgesic effect. Given the potential that has been demonstrated, but limited by the paucity of high-quality studies, further controlled studies are needed to establish and standardize the clinical use of the method.


Resumo Antecedentes A dor do membro fantasma (DMF) ocorre após amputações e pode persistir de forma crônica e debilitante. A estimulação magnética transcraniana repetitiva (EMTr) é um método de neuromodulação não invasivo capaz de influenciar a função cerebral e modular a excitabilidade cortical. Sua eficácia no tratamento da dor crônica é promissora. Objetivo Avaliar as evidências sobre a eficácia e segurança do uso da EMTr no tratamento da DMF, observando os parâmetros de estimulação utilizados, efeitos colaterais e benefícios da terapia. Métodos Trata-se de uma revisão sistemática de artigos científicos publicados na literatura nacional e internacional utilizando plataformas eletrônicas. Resultados Foram identificados 252 artigos. Duzentas e quarenta e seis publicações foram removidas por estarem duplicadas ou atenderem aos critérios de exclusão. Após a seleção, foram revisados seis estudos, sendo dois ensaios clínicos randomizados e quatro relatos de caso. Todos os estudos avaliados indicaram algum grau de benefício da EMTr no alívio dos sintomas dolorosos, mesmo que temporariamente. A percepção da dor foi menor ao final do tratamento quando comparada ao período anterior às sessões e permaneceu durante o acompanhamento do paciente. Não houve padronização dos parâmetros de estimulação utilizados. Não houve relatos de eventos adversos graves. Os efeitos da terapia a longo prazo não foram avaliados. Conclusão Existem alguns benefícios, mesmo que temporários, no uso da EMTr para alívio dos sintomas dolorosos na DMF. A estimulação de alta frequência em M1 demonstrou um efeito analgésico significativo. Dado o potencial demonstrado, mas limitado pela escassez de estudos de alta qualidade, são necessários mais estudos controlados para estabelecer e padronizar o uso clínico do método.

12.
Gels ; 9(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38131930

RESUMO

Synthetic phantoms that recreate the characteristics of biological tissues are valuable tools for systematically studying and comprehending physiologies, pathologies, and biological processes related to tissues. The reproduction of mechanical and optical properties allows for the development and evaluation of novel systems and applications in areas such as imaging, optics, ultrasound, or dosimetry, among others. This paper proposes a methodology for manufacturing agarose-based phantoms that mimics the optical properties of healthy brain tissue within the wavelength infrared range of 800 to 820 nm. The fabrication of such phantoms enables the possibility of testing and experimentation in controlled and safe environments toward the design of new near-infrared multispectral imaging systems in neurosurgery. The results of an experimental optical characterization study indicate the validity and reliability of the proposed method for fabricating brain tissue phantoms in a cost-effective and straightforward fashion.

13.
Phys Med Biol ; 68(20)2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37733054

RESUMO

Objective.To present an innovative approach for the design of a 3D mammographic phantom for medical equipment quality assessment, estimation of the glandular tissue percentage in the patient's breast, and emulation of microcalcification (µC) breast lesions.Approach.Contrast-to noise ratio (CNR) measurements, as well as spatial resolution and intensity-to-glandularity calibrations under mammography conditions were performed to assess the effectiveness of the phantom. CNR measurements were applied to different groups of calcium hydroxyapatite (HA) and aluminum oxide (AO)µCs ranging from 200 to 600µm. Spatial resolution was characterized using an aluminum plate contained in the phantom and standard linear figures of merit, such as the line spread function and modulation transfer function (MTF). The intensity-to-glandularity calibration was developed using an x-ray attenuation matrix within the phantom to estimate the glandular tissue percentage in a breast with a compressed thickness of 4 cm.Main results.For the prototype studied, the minimum confidence level for detecting HAµCs is 95.4%, while for AOµCs is above 68.3%. It was also possible to determine that the MTF of the commercial mammography machine used for this study at the Nyquist frequency is 41%. Additionally, a one-to-one intensity-to-glandularity calibration was obtained and verified with Monte-Carlo simulation results.Significance.The phantom provides traditional arrangements presented in accreditation phantoms, which makes it competitive with available devices, but excelling in regarding affordability, modularity, and inlays distribution. Moreover, its design allows to be positioned in close proximity to the patient's breast during a medical screening for a simultaneous x-ray imaging, such that the features of the phantom can be used as reference values to specify characteristics of the real breast tissue, such as proportion of glandular/adipose composition and/orµC type and size lesions.


Assuntos
Mama , Mamografia , Humanos , Mamografia/métodos , Mama/diagnóstico por imagem , Simulação por Computador , Imagens de Fantasmas , Raios X
14.
Appl Radiat Isot ; 200: 110978, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37603966

RESUMO

This work aims to model and characterize the radiation beam of one Accuray tomotherapy equipment using the Monte Carlo Code MCNP5 (Monte Carlo N-Particle). This tomotherapy equipment is used for delivering high doses of radiation in tumor regions to kill cancer cells and shrink the tumor during radiation therapy of cancer patients, however, the radiation can damage surrounding areas and nearby organs at risk (OAR) if the radiation field is not well delimited. In particular, intensity-modulated radiotherapy treatments (IMRT) with tomotherapy equipment offer great benefits to patients allowing treatment of tumor regions without affecting surrounding areas and OAR. Nowadays, it is well known that a correct simulation of transport of radiation in tomotherapy equipment facilitates considerably the estimation of ideal doses in the tumor, surrounding regions, and OAR. For that reason, in this work, we simulated the geometry of the 6 MV ACCURAY Tomotherapy equipment of the CECAN using the MCNP5. The model includes a TomoLINAC consisting of an electron source that emits Gaussian distribution particles with an average energy of 5.7 MeV and width of 0.3 MeV. The emitted particles impact the tungsten target and pass through primary collimators and jaws that define the irradiation field in the isocenter. To validate the geometry and radiation transport in the TomoLINAC the curves of depth dose percentage (PDD) estimated by simulation and the curves measured experimentally were tuned. In the same way, the simulated transverse and longitudinal profiles were compared with the experimental results. In addition, a comparison between the qualities of the radiation beam characterized with MCNP and measured experimentally in CECAN showed a deviation of 1%. For the simulations, cylindrical detectors located inside a water phantom were considered and it was employed the tally *F8. A good agreement was observed between the PDD's curves obtained from the simulation and those measured experimentally for a field of 5 × 10 cm2 in the isocenter and SSD (distance from the source to the surface) of 85 cm. Also, the comparison between the simulated and experimental transverse profiles obtained at 1.5 cm, 10 cm and 15 cm depth with a radiation field of 5 × 40 cm2 showed very good agreement. The longitudinal profiles were estimated with the same depths as the transverse ones, but for each of them, the openings of the jaws were 5.0 cm, 2.5 cm and 1.0 cm in the longitudinal direction, which corresponds to the direction in which the patient's table moves. The comparison between the simulated and experimental longitudinal profiles showed good concordance too. Once the radiation beam of the ACCURAY tomotherapy equipment had been characterized, experimental dose measurements were made using a Cheese phantom and two A1SL ionization chambers. These results obtained experimentally were compared with those estimated with MCNP for a field of 5 × 40 cm2 at the isocenter and SAD of 85 cm and, it was concluded that both results were similar considering the regions of uncertainty. Finally, we must highlight that the modeling and characterization of the radiation beam of CECAN's ACCURAY tomotherapy equipment can be a key tool for dose estimations in different cancer treatment plans and future research.

15.
Bioelectrochemistry ; 154: 108549, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37639773

RESUMO

Electrochemotherapy (ECT) and Irreversible electroporation (IRE) are cancer treatments based on electric field distribution in tissues. Solanum tuberosum (potato tissue) phantom is known to mimic changes in the electrical conductivity that occur in animal tissues during electroporation (EP). Electric field distribution is assessed through enzymatic staining. However, the 24-h wait for this assessment could slow agile response scenarios. We developed and validated the Musa acuminata (cavendish banana) conductivity model, which quickly evaluates EP by tissue staining. We investigated the frequency response of the tissue using impedance spectroscopy analysis, conductivity changes, and enzymatic staining. We optimized three usual EP models: adapted Gompertz, smoothed Heaviside, and the sigmoid or logistic function. We found dielectric parameters in banana tissue similar to those in potato (electrical conductivity of 0.035 S/m and relative permittivity of 4.1×104). The coefficients of determination R2 were 99.94% (Gompertz), 99.85% (Heaviside), and 99.58% (sigmoid). The sigmoid and Heaviside functions described the calibration and validation electric currents with 95% confidence. We observed the electroporated areas in bananas 3h30m after EP. Staining was significant after 450 V/cm. The conductivity model of Musa acuminata suits treatment planning, hardware development, and training scenarios. Banana phantom supports the 3Rs practice and is a reliable alternative for potato in EP studies.


Assuntos
Eletroquimioterapia , Musa , Animais , Terapia com Eletroporação , Eletroporação , Condutividade Elétrica
16.
J Ultrason ; 23(93): e73-e79, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37520745

RESUMO

Aim: We sought to create and describe a self-made simulator designed and created for teaching purposes: a high-fidelity ultrasound phantom for demonstrating antral follicle count, ultrasound supervision of controlled of ovarian stimulation, and ultrasound-guided oocyte retrieval. Materials and methods: The uterus and ovaries of the ultrasound phantom were made from beef tongue, a male condom, latex gloves, cotton suture threads, bi-distilled water, and ultrasound gel. The components were placed in a pelvis created using three-dimensional (3D) printing. The phantom was presented to and evaluated by a group of 14 physicians pursuing a postgraduate course in reproductive medicine. Two training stations were structured: one to simulate antral follicle count and controlled ovarian stimulation and the other to simulate ultrasound-guided oocyte retrieval. Future specialists were requested to complete a feedback questionnaire evaluating the self-made simulator and the two practice stations. Results: The transvaginal ultrasound phantom was successfully created, making it possible to simulate antral follicle count, ultrasound control of ovarian hyperstimulation, and oocyte retrieval, and to capture ultrasound images. A review of the answers provided in the feedback questionnaire showed that the phantom had a good appearance and design, was realistic, helped to improve motor coordination, and could be a useful tool in the training of specialists in assisted reproduction. Conclusion: This phantom was designed to enable instruction and practice in the evaluation of ovarian follicles and ultrasound-guided oocyte retrieval in a supervised training environment. This self-made simulator is proposed as a training tool that could be included in the curricular structure of residency and postgraduate programs in reproductive medicine.

17.
J Pain Palliat Care Pharmacother ; 37(2): 194-208, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929710

RESUMO

OBJECTIVE: Painful Phantom Limb Syndrome (PPLS) occurs in 50 to 80% of patients undergoing amputation, having a great impact on quality of life, productivity and psychosocial sphere. The objective of this review is to summarize the pharmacological and non-pharmacological strategies, surgical optimization, and provide a multidisciplinary approach aimed at reducing the incidence of chronic pain associated with PPLS in patients undergoing limb amputation. METHODS: A narrative review was carried out using Medline, Pubmed, Proquest, LILACS and Cochrane, searching for articles between 2000 and 2021. Articles describing the epidemiology, pathophysiological considerations, and current treatments were selected after a screening process. RESULTS: A multidisciplinary and multimodal approach is required in PPLS, and should include the use of regional techniques, and adjuvants such as NSAIDs, ketamine, lidocaine and gabapentinoids. In addition, an evaluation and continuous management of risk factors for chronic pain in conjunction with the surgical team is necessary. CONCLUSION: The current literature does not support that a single technique is effective inthe prevention of PPLS. However, adequate acute pain control, rehabilitation and early restoration of the body scheme under a multidisciplinary and multimodal approach have shown benefit in the acute setting.


Assuntos
Dor Crônica , Membro Fantasma , Humanos , Membro Fantasma/tratamento farmacológico , Dor Crônica/tratamento farmacológico , Dor Crônica/etiologia , Qualidade de Vida , Amputação Cirúrgica , Manejo da Dor/métodos
18.
Magn Reson Med ; 89(6): 2402-2418, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36695213

RESUMO

PURPOSE: QSM outside the brain has recently gained interest, particularly in the abdominal region. However, the absence of reliable ground truths makes difficult to assess reconstruction algorithms, whose quality is already compromised by additional signal contributions from fat, gases, and different kinds of motion. This work presents a realistic in silico phantom for the development, evaluation and comparison of abdominal QSM reconstruction algorithms. METHODS: Synthetic susceptibility and R 2 * $$ {R}_2^{\ast } $$ maps were generated by segmenting and postprocessing the abdominal 3T MRI data from a healthy volunteer. Susceptibility and R 2 * $$ {R}_2^{\ast } $$ values in different tissues/organs were assigned according to literature and experimental values and were also provided with realistic textures. The signal was simulated using as input the synthetic QSM and R 2 * $$ {R}_2^{\ast } $$ maps and fat contributions. Three susceptibility scenarios and two acquisition protocols were simulated to compare different reconstruction algorithms. RESULTS: QSM reconstructions show that the phantom allows to identify the main strengths and limitations of the acquisition approaches and reconstruction algorithms, such as in-phase acquisitions, water-fat separation methods, and QSM dipole inversion algorithms. CONCLUSION: The phantom showed its potential as a ground truth to evaluate and compare reconstruction pipelines and algorithms. The publicly available source code, designed in a modular framework, allows users to easily modify the susceptibility, R 2 * $$ {R}_2^{\ast } $$ and TEs, and thus creates different abdominal scenarios.


Assuntos
Encéfalo , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Abdome/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos
19.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1441478

RESUMO

Introducción: La amputación de la extremidad con frecuencia da lugar a alteraciones sensoriales, dolorosas o no, tales como el síndrome del miembro fantasma, que dificulta el proceso de rehabilitación y afecta el estado psicológico del paciente. El dolor de miembro fantasma ha sido descrito como una condición en la que los pacientes experimentan una sensación dolorosa en el miembro ausente. Objetivo: Describir aspectos esenciales del dolor fantasma como complicación en los pacientes amputados Métodos: Se realizó una búsqueda de la literatura publicada durante el período comprendido entre enero de 2015 y diciembre de 2021 que hiciera referencia al dolor en miembro fantasma en paciente amputado. Resultados: Entre las causas que conllevan a la amputación de una extremidad se encuentran los problemas vasculares, trauma, cáncer y alteraciones congénitas, es importante tenerlas en consideración debido a los efectos psicológicos y socioeconómicos que puede tener en el paciente. El síndrome del miembro fantasma se divide en miembro o sensación fantasma, dolor de miembro fantasma y muñón doloroso. Es importante hacer distinciones entre ellos, lo que ayuda a evaluar la magnitud del problema y el tratamiento que es diferente. El tratamiento convencional no ha sido muy efectivo. Conclusiones: Se describieron los aspectos esenciales del dolor fantasma como complicación en los pacientes amputados, el manejo y tratamiento del dolor de miembro fantasma en miembros amputados, constituye una prioridad a vencer dentro de las pautas de la medicina moderna(AU)


Introduction: Limb amputation often gives rise to sensory alterations, painful or not, such as phantom limb syndrome, which hinders the rehabilitation process and affects the patient's psychological state. Phantom limb pain has been described as a condition in which patients experience a painful sensation in the missing limb. Objective: To describe essential aspects of phantom pain as a complication in amputee patients. Methods: A search of the literature published between January 2015 and December 2021 that referred to phantom limb pain in amputee patients was carried out. Results: Among the causes that lead to the amputation of a limb are vascular problems, trauma, cancer and congenital alterations, it is important to take them into consideration due to the psychological and socioeconomic effects that they can have on the patient. Phantom limb syndrome is divided into phantom limb or sensation, phantom limb pain, and painful stump. It is important to make distinctions between them, which helps to assess the magnitude of the problem and the treatment that is different. Conventional treatment has not been very effective. Conclusions: The management and treatment of phantom limb pain in amputated limbs is a priority to be overcome within the guidelines of modern medicine, which is why care intervention is necessary in order to improve the quality of life of the amputated patient and their better rehabilitation(AU)


Assuntos
Humanos
20.
Sensors (Basel) ; 22(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36560232

RESUMO

This work aimed to develop a real-time test platform for systems associated with the tactile internet area. The proposal comprises a master device, a communication channel and a slave device. The master device is a tactile glove (wearable technology) that works as a tactile interface based on vibratory feedback. The master device can interact with virtual elements (local or remote). The Matlab/Simulink environment and a robotics toolbox form the communication channel and the slave device. The communication channel introduces a bidirectional connection of variable latency, and the slave device is defined as a robotic phantom omni manipulator emulated in Matlab/Simulink. The virtual robotic manipulator, the slave device, can generate different types of tactile sensations in the tactile glove, that is, in the master device. The platform can model tactile sensations such as coarse roughness, fine roughness, smoothness, dripping and softness. The proposed platform presented adequate results and can be used to test various algorithms and methods correlated to the tactile internet.


Assuntos
Robótica , Interface Usuário-Computador , Tato , Robótica/métodos , Algoritmos , Retroalimentação , Desenho de Equipamento
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