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1.
Reprod Domest Anim ; 57 Suppl 5: 34-44, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35748405

RESUMO

Ultrasound technology has led to new lines of research in equine reproduction, and it has helped to greatly improve clinical diagnosis and reproductive outcomes in equine practice. This review aims to discuss the potential clinical uses and new approaches of ultrasonography in equine reproduction. Doppler modalities are usually used to evaluate the vascularization of the follicles, corpus luteum (CL), and the uterus in the mare for diagnostic purposes. Inclusion of Doppler ultrasound in artificial insemination and embryo transfer programs could improve the reproductive outcome of these techniques. Better selection of recipients based on CL functionality, early pregnancy diagnosis 7-8 days postovulation of the donor before flushing or diagnosis of mares with endometritis with pathological increases of blood flow are examples of clinical applications in the mare. In the stallion, colour Doppler ultrasound has improved the diagnostic potential of B-mode ultrasound, improving the differential diagnosis of pathologies such as testicular torsion (decrease or absence of blood flow in the cord) and orchitis (increased blood flow in the cord). The incorporation of pulsed Doppler ultrasound into the reproductive evaluation of the stallion has enabled early identification of stallions with testicular dysfunction, thus allowing administration of timely treatment and subsequent improvements of the fertility prognosis for these animals. In addition, this technique has been used in the monitoring of patients undergoing medical and surgical treatments, thus verifying their efficacy. Recently, computer-assisted pixel analysis using specific software has been performed in research work in order to semi-quantitatively evaluate the vascularization (colour and power Doppler) and echotexture of different organs. These softwares are now being developed for clinical purposes, as is the case with Ecotext, a computer program developed for the evaluation of testicular echotexture, providing information on testicular functionality.


Assuntos
Corpo Lúteo , Medicina Reprodutiva , Animais , Corpo Lúteo/irrigação sanguínea , Feminino , Cavalos , Inseminação Artificial/veterinária , Masculino , Gravidez , Ultrassonografia/veterinária , Ultrassonografia Doppler em Cores
2.
Sensors (Basel) ; 21(21)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34770599

RESUMO

A multiple-input multiple-output (MIMO) method that shares the same frequency band can efficiently increase radar performance. An essential element of a MIMO radar is the orthogonality of the waveform. Typically, orthogonality is obtained by spreading different signals into divided domains such as in time-domain multiplexing, frequency-domain multiplexing, and code domain multiplexing. This paper proposes a method of spreading the interference signals outside the range bins of interest for pulse doppler radars. This is achieved by changing the pulse repetition frequency under certain constraints, and an additional gain can be obtained by doppler processing. This method is very effective for improving the angular accuracy of the MIMO radar for a small number of air targets, although it may have limitations in use for many targets or in high clutter environments.

3.
J Obstet Gynaecol ; 41(6): 870-875, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33064041

RESUMO

We analysed the effectiveness of transvaginal ultrasonographic and foetal/maternal pulse Doppler findings as predictors of labour onset within 1 week. We included 22 single normal pregnancies and evaluated the one-point and short- and long-term differences in uterine artery pulsatility index (PI), umbilical artery PI, middle cerebral artery PI (MCA-PI), peak systolic velocity, and cervical length (CL). Presence of funnelling and membrane separation over the internal cervical os was evaluated. Significant changes were observed in the one-point measurement of and short-term and long-term differences in CL, the one-point measurement of and long-term difference in MCA-PI, and the presence of membrane separation (Grade 2). In multivariate analysis, the significant predictors were short-term differences in CL (odds ratio [OR]: 5.27), long-term differences in MCA-PI (OR: 13.3), and presence of membrane separation (Grade 2) (OR: 5.38). Transvaginal ultrasonographic and foetal pulse Doppler findings were effective predictors of labour onset within 1 week.Impact statementWhat is already known on this subject? Parameters reported to predict labour onset include the Bishop score, cervical length, decreased long-term cervical length, funnelling of the internal cervical os, and adrenal gland volume.What do the results of this study add? Short-term changes in cervical length, long-term changes in middle cerebral artery pulsatility index, and the presence of membrane separation Grade 2 were found to be useful predictive factors of labour onset in this study.What are the implications of these findings for clinical practice and/or further research? The prediction of labour onset enables clinicians to properly manage pregnancy and delivery considering maternal and foetal conditions.


Assuntos
Início do Trabalho de Parto , Ultrassonografia Doppler/estatística & dados numéricos , Ultrassonografia Pré-Natal/estatística & dados numéricos , Adulto , Medida do Comprimento Cervical/estatística & dados numéricos , Feminino , Humanos , Artéria Cerebral Média/diagnóstico por imagem , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Gravidez , Fluxo Pulsátil , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal/métodos , Artéria Uterina/diagnóstico por imagem , Adulto Jovem
4.
Sensors (Basel) ; 20(9)2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344899

RESUMO

Linear frequency modulation (LFM) waveforms have high Doppler-shift endurance because of the relative wide modulation bandwidth to the Doppler variation. The Doppler shift of the moving objects, nevertheless, constantly introduces obscure detection range offsets despite the exceptional Doppler tolerance in detection energy loss from LFM. An up-down-chirped LFM waveform is an efficient scheme to resolve the true target location and velocity by averaging the detection offset of two detection pairs from each single chirp LFM in opposite slopes. However, in multiple velocity-vary-target scenarios, without an efficient grouping scheme to find the detection pair of each moving target, the ambiguous detection results confine the applicability of precise target estimation by using these Doppler-tolerated waveforms. A succinct, three-multi-Doppler-shift-compensation (MDSC) scheme is applied to resolve the range and velocity of two moving objects by sorting the correct LFM detection pair of each target, even though the unresolvable scenarios of two close-by targets imply a fatal disability of detecting objects under a cluttered background. An innovative clutter-suppressed multi-Doppler-shift compensation (CS-MDSC) scheme is introduced in this research to compensate for the critical insufficient of resolving two overlapping objects with different velocities by solely MDSC. The CS-MDSC has been shown to successfully overcome this ambiguous scenario by integrating Doppler-selective moving target indication (MTI) filters to mitigate the distorting of near-zero-Doppler objects.

5.
Sensors (Basel) ; 19(8)2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31013743

RESUMO

We examine a multiple object tracking problem by jointly optimizing the transmit waveforms used in a multimodal system. Coexisting sensors in this system were assumed to share the same spectrum. Depending on the application, a system can include radars tracking multiple targets or multiuser wireless communications and a radar tracking both multiple messages and a target. The proposed spectral coexistence approach was based on designing all transmit waveforms to have the same time-varying phase function while optimizing desirable performance metrics. Considering the scenario of tracking a target with a pulse-Doppler radar and multiple user messages, two signaling schemes were proposed after selecting the waveform parameters to first minimize multiple access interference. The first scheme is based on system interference minimization, whereas the second scheme explores the multiobjective optimization tradeoff between system interference and object parameter estimation error. Simulations are provided to demonstrate the performance tradeoffs due to different system requirements.

6.
Sensors (Basel) ; 18(5)2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29751525

RESUMO

In previous works, an optical technique for extraction and separation of remote static vibrations has been demonstrated. In this paper, we will describe an approach in which RF speckle movement is used to extract remote vibrations of a static target. The use of conventional radar Doppler methods is not suitable for detecting vibrations of static targets. In addition, the speckle method has an important advantage, in that it is able to detect vibrations at far greater distances than what is normally detected in classical optical methods. The experiment described in this paper was done using a motorized vehicle, which engine was turned on and off. The results showed that the system was able to distinguish between the different engine states, and in addition, was able to determine the vibration frequency of the engine. The first step towards real time detection of human vital signs using RF speckle patterns is presented.

7.
Heart Vessels ; 32(6): 708-713, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27882404

RESUMO

Wild-type transthyretin amyloidosis (ATTRwt) is often overlooked in elderly patients with left ventricular hypertrophy (LVH). Impaired atrial function, in addition to ventricular diastolic dysfunction, is one of the hallmarks of cardiac amyloidosis. Here, we assessed the hypothesis that atrial function evaluated by A-velocity in pulse Doppler echocardiography is useful to differentiate ATTRwt in elderly patients with LVH. We analyzed 133 consecutive patients who underwent tissue biopsy to rule out infiltrative cardiomyopathy in our institute. We excluded patients younger than 50 years, without LVH (LV thickness was less than 12 mm), with other types of cardiac amyloidosis and patients with chronic atrial fibrillation, and analyzed remaining 51 patients (ATTRwt: 16, non-ATTRwt: 35). ATTRwt patients were significantly older and had advanced heart failure compared with non-ATTRwt group. In echocardiography, E/A, E/e', and relative wall thickness was significantly higher in ATTRwt group than non-ATTRwt group. A-velocity was significantly decreased in ATTRWT group compared with non-ATTRwt group (40.8 ± 20.8 vs. 78.7 ± 28.2 cm/s, p = 0.0001). Multivariate logistic analysis using eight forced inclusion models identified trans-mitral Doppler A-wave velocity was more significant factor of cardiac amyloidosis in ATTRwt. In receiver operating characteristic (ROC) analysis, the area under the curve (AUC) for A-wave velocity in discrimination between ATTRwt and non-ATTRwt were 0.86 (CI 0.76-0.96, p < 0.001). The cut-off value was 62.5 cm/s, and it yielded the best combination of sensitivity (69.7%) and specificity (87.5%) for prediction of amyloidosis. We concluded that reduced A-velocity predicts the presence of ATTRwt in elderly patients with LVH in sinus rhythm.


Assuntos
Neuropatias Amiloides Familiares/complicações , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Neuropatias Amiloides Familiares/diagnóstico por imagem , Neuropatias Amiloides Familiares/patologia , Ecocardiografia Doppler , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etiologia , Japão/epidemiologia , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Onda de Pulso , Curva ROC , Estudos Retrospectivos
8.
JSES Int ; 6(4): 623-630, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35813140

RESUMO

Background: An association has been reported between rotator cuff tear and inflammation. We hypothesized that blood flow in the anterior humeral circumflex artery would reflect synovial inflammation in the shoulder. This study aimed to clarify the association of blood flow in the anterior humeral circumflex artery with synovial inflammation and shoulder pain in patients with rotator cuff tears. Methods: In this prospective, cross-sectional study, tissue samples from the synovium in the rotator interval were obtained from 33 patients undergoing arthroscopic rotator cuff repair. Reverse transcription-polymerase chain reaction and real-time polymerase chain reaction were performed to determine the messenger RNA expression of inflammatory mediators, growth factors, and matrix metalloproteinases. Additional tissue samples were fixed for histologic evaluation. Before surgery, we measured the peak systolic velocity in the anterior humeral circumflex artery using pulse Doppler ultrasonography. Results: The peak systolic velocity in the anterior humeral circumflex artery was positively correlated with the messenger RNA expression of interleukin 1ß, interleukin 8, and matrix metalloproteinase 3 genes (r = 0.49, P = .004; r = 0.55, P = .001; and r = 0.39, P = .026, respectively), as well as histologic synovitis scores (r = 0.48, P = .005). Additionally, it was significantly higher in patients with resting pain than in those without resting pain (P = .048). Conclusion: The peak systolic velocity in the anterior humeral circumflex artery is associated with the severity of synovial inflammation. Our results suggest that assessing the peak systolic velocity in the anterior humeral circumflex artery is useful for evaluating the severity of synovial inflammation.

9.
J Vasc Access ; : 11297298221109662, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35791079

RESUMO

BACKGROUND: MicroBubbles Time test (MBT), consisting in the rapid infusion of saline with addition of air microbubbles, visualized by B-mode echocardiography, represents a potential alternative to Intracavitary ECG (IC-ECG) and chest X-ray for central venous catheters (CVCs) tip location. Even if promising, this technique lacks of standardization: a clear time cut-off between bubble infusion and their detection in heart's right chambers hasn't been yet established. At these regard, microbubbles could be also detected as microembolic signals (MES) with an alternative ultrasound technique: the pulse wave Doppler (PW). OBJECTIVE AND METHODS: The first aim of this pilot study is to establish agreement of MBT with PW test (MBT-PW) compared with reference standard IC-ECG and normal MBT for tip location on CVCs. Corrected tip's position was established through reference standard IC-ECG, afterward MBT-PW was performed, with the sample volume placed at tricuspid valve to detect MES simultaneously with micro-bubbles injection in CVCs. The second aim was to evaluate inter-observer variability for MES detection and grading. RESULTS: Eight patients were enrolled; we obtained three records for each patients (24 with MBT and 24 with MBT-PW, the two techniques were acquired simultaneously). Inter-methods agreement through reference standard IC-ECG versus MBT-PW and MBT versus MBT-PW methodic was satisfying (Cohen's kappa value = 1). MBT-PW and MBT signals were recorded within the first heart beat after microbubble infusion in all patients. Mean time delay thorough MBT-PW and MBT was 0.76 ±0.07 and 0.78 ± 0.07 s respectively; Intraclass correlation coefficient was 0.992 (95% CI: 0.981-0.996) suggesting excellent correlation. Inter-observer variability for positive MBT-PW evaluation was optimal (Cohen's kappa value was 1), while indicated substantial agreement for MES grade evaluation (Fleiss' Kappa value was 0.704; 95% CI: 0.328-1.000). CONCLUSIONS: Our study supports agreement between MBT-PW and reference standard IC-ECG for tip location. Satisfactory agreement was observed also for MBT-PW and MBT.

10.
Animals (Basel) ; 10(11)2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182393

RESUMO

Pulsed-wave Doppler ultrasonography (PwD) is a method used to rapidly and noninvasively assess blood flow dynamics of the canine prostate. Modifications in gland vascularization can affect seminal plasma production and consequently sperm quality. The aim of this study was to determine the normal blood flow parameters of the prostate artery in beagle dogs and to analyze the correlations between vascular flow and semen quality characteristics. PwD was performed on five beagle dogs (5-6 years) measuring vascular features in four different locations of the prostatic artery (cranial, subcapsular, parenchymal and caudal); the measured features were peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI). Ejaculates were obtained using digital manipulation and semen quality was evaluated by determining macroscopic (total volume, sperm-rich fraction volume, color and pH) and microscopic (sperm motility, morphology, viability and acrosome integrity) characteristics. The values of PSV, PI and RI in cranial and caudal prostatic arteries were significantly higher than in subcapsular and parenchymal arteries (p < 0.05). Moreover, a positive correlation of PSV value in the cranial region of the prostatic artery with total ejaculate volume (p < 0.01, r = 0.612) and sperm concentration (p < 0.01, r = 0.587) was determined. PI index was negatively correlated with sperm concentration (p < 0.01, r = -0.709). In conclusion, the results suggest that the prostatic artery blood flow parameters can affect macroscopic semen quality characteristics in healthy dogs.

11.
J Clin Sleep Med ; 14(7): 1249-1254, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29991417

RESUMO

STUDY OBJECTIVES: To validate Impulse radio ultra wideband pulse-doppler radar technology against polysomnography (PSG) for sleep assessment. METHODS: In all, 12 participants were recruited and their overnight sleep was assessed both by a Novelda XeThru radar and PSG. Two subjects had two nightly recordings, whereas 10 had one recording. Epoch by epoch (30 seconds) comparisons from bedtime to rise time were conducted. Concordance was estimated in terms of the mean difference between the radar and the PSG estimates regarding sleep onset latency, wake time after sleep onset and total sleep time. In addition, accuracy, sensitivity, specificity and Cohen kappa were calculated. RESULTS: The mean difference (minutes) between the radar and the PSG registrations was -5.7 minutes (standard deviation [SD] = 22.1 minutes) for sleep onset latency, 6.4 minutes (SD = 32.5 minutes) for wake after sleep onset, and 1.5 minutes (SD = 24.6 minutes) for total sleep time. The mean values obtained for accuracy, sensitivity, specificity and Cohen kappa were 0.931, 0.961, 0.695 and 0.670, respectively. CONCLUSION: Impulse radio ultra wideband radar technology is a promising tool in terms of affordable and practical objective sleep assessment. Further technical development and more validation studies are needed in order to conclude about the utility potential of this device.


Assuntos
Radar , Processamento de Sinais Assistido por Computador , Sono/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polissonografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tempo , Adulto Jovem
12.
Arq. bras. med. vet. zootec. (Online) ; 69(3): 618-622, jun. 2017. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-846903

RESUMO

Dioctophyme renale é um parasito que afeta tanto animais como humanos e tem como órgão de eleição o rim direito. Relata-se o caso clínico-cirúrgico de um paciente canino com histórico de eliminação de três exemplares de D. renale pela urina e presença de parasitos no rim esquerdo e na cavidade abdominal. No Hospital de Clínicas Veterinárias da Universidade Federal de Pelotas, foram realizados exames pré-cirúrgicos, entre eles a ultrassonografia abdominal, que identificou a localização dos nematódeos, e o exame de Doppler pulsado dos vasos intrarrenais, que demonstrou aumento nos índices resistivos nas regiões avaliadas. O paciente foi conduzido para a realização de laparotomia exploratória, sendo removidos 23 parasitos da cavidade abdominal. A presença de D. renale causa graves lesões nos rins e nos demais órgãos da cavidade abdominal, sendo essencial o diagnóstico precoce e a remoção dos nematódeos para recuperação do paciente.(AU)


Dioctophyme renale is a parasite that attacks animals as well as humans and has the right kidney as a preferred target organ. This document reports the case of a clinical-chirurgical canine patient with a history of elimination of three D. renale samples through its urine and presence of parasites at its left kidney and abdominal cavity. Pre-cirurgical exams were performed at the Veterinary Hospital of the Federal University of Pelotas. Among these exams, abdominal ultrasonography identified the nematode's location and the Pulse-Doppler of the intrarenal vessels showed an increase in the resistive indices of the evaluated areas. An Exploratory Laparotomy was conducted with the patient who had 23 parasites removed from its abdominal cavity. The presence of D. renale causes severe lesions at kidneys and other organs of the abdominal cavity, for this reason early diagnosis and nematode´s removal are essential for the patient's recovery.(AU)


Assuntos
Animais , Cães , Cavidade Abdominal/parasitologia , Dioctophymatoidea , Rim/parasitologia , Urina/parasitologia , Laparotomia/veterinária , Ultrassonografia Doppler de Pulso/veterinária
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