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1.
Animals (Basel) ; 14(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38791622

RESUMO

In this multicenter, prospective, observational study, abdominal aortic flow was examined with pulsed-wave Doppler ultrasound in dogs with a left-to-right shunting patent ductus arteriosus (PDA) and in apparently healthy dogs. Forty-eight dogs with a PDA and 35 controls were included. In the dogs with a PDA, 37/48 had hemodynamically significant PDAs (hsPDAs) while 11/48 had non-hsPDAs, based on the presence or absence of echocardiographic signs of left-sided volume overload, respectively. In 12 dogs (4/35 control dogs, 7/37 dogs with an hsPDA and 1/11 dogs with a non-hsPDA), the diastole was too short to visualize the end-diastolic flow. Antegrade end-diastolic flow was observed in 30/35 controls and 6/11 dogs with a non-hsPDA. Absent end-diastolic flow was observed in 1/35 control dogs and 3/11 dogs with a non-hsPDA. Retrograde end-diastolic flow was observed in 30/37 dogs with an hsPDA and 1/11 dogs with a non-hsPDA. Twenty-one dogs (15 with an hsPDA and 6 with a non-hsPDA) were reassessed after PDA closure, and, in 19/21, end-diastolic flow was visualized: 17/19 showed an antegrade flow, 1/19 an absent flow and 1/19 a retrograde flow. Sensitivity and specificity of retrograde end-diastolic flow for detection of hsPDAs were 100% and 90%, respectively. In conclusion, ultrasonographic assessment of abdominal aortic flow was feasible in dogs with PDA. However, end-diastolic flow was not always visualized. The presence of a retrograde end-diastolic flow was an accurate finding for discriminating hsPDAs and non-hsPDAs.

2.
Fetal Diagn Ther ; : 1-8, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38643759

RESUMO

INTRODUCTION: No evidence-based protocols exist for fetal cardiac monitoring during fetoscopic myelomeningocele (fMMC) repair and intraprocedural spectral Doppler data are limited. We determined the feasibility of continuous fetal echocardiography during fMMC repair and correlated Doppler changes with qualitative fetal cardiac function during each phase of fMMC repair. METHODS: Patients undergoing fMMC repair had continuous fetal echocardiography interpreted in real-time by pediatric cardiology. Fetal data included fetal heart rate (FHR), qualitative cardiac function, mitral and tricuspid valve inflow waveforms, and umbilical artery (UA), umbilical vein (UV), ductus arteriosus (DA), and ductus venosus (DV) Dopplers. RESULTS: UA abnormalities were noted in 14/25 patients, UV abnormalities were observed in 2 patients, and DV and DA abnormalities were each noted in 4 patients. Qualitative cardiac function was normal for all patients with the exception of one with isolated left ventricular dysfunction during myofascial flap creation, concurrent with an abnormal UA flow pattern. All abnormalities resolved by the first postoperative day. CONCLUSIONS: Continuous fetal echocardiography was feasible during all fMMC repairs. Spectral Doppler changes in the UA were common during fMMC procedures but qualitative cardiac dysfunction was rare. Abnormalities in the UV, DV, and DA Dopplers, FHR, and cardiac function were less common findings.

3.
Endocr Pract ; 30(5): 465-469, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38331386

RESUMO

OBJECTIVE: To assess the bedside utility of Spectral Doppler Ultrasound (SDUS) in the initial evaluation of patients presenting with thyrotoxicosis. METHODS: This is a retrospective cross-sectional study of patients diagnosed with thyrotoxicosis at an academic outpatient endocrinology clinic from August 2019 to November 2022. The thyroid arteries' peak systolic velocities (PSV) were measured bilaterally using SDUS. PSV ≥40 cm/s in at least a single thyroid artery was considered a reasonable cut-off for Graves' disease and PSV of perinodular artery ≥ 25 cm/s for toxic adenoma. RESULTS: We identified 73 patients. Mean age ± standard deviation 45.2 ± 16.4 years, 54 (74.0%) were female, 49 (67.1%) were Caucasian, 23 (31.5%) were African American, and 1 (1.4%) was Asian. The confirmed diagnoses were 48 (65.8%) Graves' disease, 13 (17.8%) thyroiditis, four (5.5%) toxic adenoma, four (5.5%) amiodarone-induced thyroiditis type 2, 1 (1.4%) toxic multinodular goiter, 1 (1.4%) had an unremarkable repeat thyroid function testing, and two (2.7%) were unconfirmed. Diagnosis based on the SDUS initial assessment was accurate in 65 (89.0%) of the patients, and it was conclusive and confirmatory during the initial encounter in 55 (75.3%) of the patients before additional testing. A thyroid scan was obtained in nine (12.3%) patients. Incorrectly diagnosed patients were observed in two patients of each of the following categories: Graves' disease, thyroiditis, toxic adenoma, and unconfirmed diagnoses. CONCLUSIONS: SDUS can be a valuable, efficient, and cost-effective bedside tool in the initial assessment of patients presenting with thyrotoxicosis.


Assuntos
Glândula Tireoide , Tireotoxicose , Humanos , Feminino , Tireotoxicose/diagnóstico por imagem , Estudos Transversais , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Glândula Tireoide/diagnóstico por imagem , Doença de Graves/diagnóstico por imagem , Ultrassonografia Doppler , Testes Imediatos
4.
Ultrasound Med Biol ; 50(3): 434-444, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38143187

RESUMO

OBJECTIVE: Post-operative brain injury in neonates may result from disturbed cerebral perfusion, but accurate peri-operative monitoring is lacking. High-frame-rate (HFR) cerebral ultrasound could visualize and quantify flow in all detectable vessels using spectral Doppler; however, automated quantification in small vessels is challenging because of low signal amplitude. We have developed an automatic envelope detection algorithm for HFR pulsed wave spectral Doppler signals, enabling neonatal brain quantitative parameter maps during and after surgery. METHODS: HFR ultrasound data from high-risk neonatal surgeries were recorded with a custom HFR mode (frame rate = 1000 Hz) on a Zonare ZS3 system. A pulsed wave Doppler spectrogram was calculated for each pixel containing blood flow in the image, and spectral peak velocity was tracked using a max-likelihood estimation algorithm of signal and noise regions in the spectrogram, where the most likely cross-over point marks the blood flow velocity. The resulting peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistivity index (RI) were compared with other detection schemes, manual tracking and RIs from regular pulsed wave Doppler measurements in 10 neonates. RESULTS: Envelope detection was successful in both high- and low-quality arterial and venous flow spectrograms. Our technique had the lowest root mean square error for EDV, PSV and RI (0.46 cm/s, 0.53 cm/s and 0.15, respectively) when compared with manual tracking. There was good agreement between the clinical pulsed wave Doppler RI and HFR measurement with a mean difference of 0.07. CONCLUSION: The max-likelihood algorithm is a promising approach to accurate, automated cerebral blood flow monitoring with HFR imaging in neonates.


Assuntos
Hemodinâmica , Ultrassonografia Doppler , Recém-Nascido , Humanos , Ultrassonografia , Ultrassonografia Doppler/métodos , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/diagnóstico por imagem , Algoritmos
5.
Animals (Basel) ; 13(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37889732

RESUMO

Udder health of dairy cows is related to their productivity and welfare. The period from dry-off to calving and early lactation is crucial. Ultrasonography is a useful and practical tool for the examination of the mammary parenchyma and blood flow. This observational study investigated the relationship between udder echotexture features, blood flow volume (BFVol) in the milk vein, milk somatic cell count (SCC) and daily milk yield (DMY) from late lactation, throughout the dry period and consecutive early lactation. Seventeen repeated measurements were performed on twenty-one Holstein cows. The udder parenchyma was examined with B-mode ultrasonography. Udder echotexture was studied using 15 features: Numerical Pixel Value (NPV), Pixel Standard Deviation (PSD), Skewness, Excess, Contrast, Homogeneity, Correlation, Entropy, Run Percentage, Long-Run Emphasis, Grey Value Distribution, Runlength Distribution, Gradient Mean Value, Gradient Variance and Percentage of Non-zero Gradients. Blood flow in the milk vein was examined with spectral Doppler. Linear mixed-effects models were employed to investigate relationships between BFVol, udder echotexture features, SCC and DMY throughout the study period. Our models showed that a 1 kg increase in DMY was associated with a significant increase of 0.25 L/min in the expected BFVol and that a 1,000,000-cells/mL increase in SCC was associated with a significant BFVol decrease of 0.49 L/min, keeping all other variables constant. Multivariable models showed significant associations between DMY and NPV, between PSD and Long-Run Emphasis, and between SCC and NPV, PSD, Gradient Mean Value, Homogeneity, Gradient Variance and Entropy. In conclusion, udder echotexture and BFVol in the milk vein are related to SCC and milk yield. Ultrasonography can be used for the comprehensive assessment of udder health in support of precision dairy farming.

6.
Med Phys ; 50(11): 6704-6713, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37793117

RESUMO

BACKGROUND: Pulsed wave Doppler ultrasound is a useful modality for assessing vascular health as it quantifies blood flow characteristics. To facilitate accurate diagnosis, accuracy and consistency of this modality should be assessed through Doppler quality assurance (QA). PURPOSE: The purpose of this study was to characterize the accuracy, reproducibility, and inter-scanner variability of ultrasound flow velocity measurements via a flow phantom, with a focus on the effect of systematic acquisition parameters on measured flow velocity accuracy. METHODS: Using a manufacturer-calibrated flow phantom, pulsed wave measurements were acquired on five clinical systems (iU22, Philips) with three models of transducers, including both linear and curvilinear models. The peak and mean flow velocities were estimated by vendor-supplied spectral analysis tools. To investigate intra- and inter-scanner variability, measurements were repeated using each scanner-transducer pair under a standardized set of conditions. Inter-scanner variability was assessed using ANOVA. Flow velocity accuracy was investigated by mean absolute percentage error. The impacts of receive gain, measurement depth, and beam steering on measured flow velocity accuracy were examined by varying each parameter over its available range and comparing to the ground truth flow velocity. RESULTS: Inter-scanner variability was statistically significant for peak flow measurements made using both linear and curvilinear transducers, though absolute differences in measured velocity were small. Inter-scanner variability was not statistically significant for mean flow velocity. Receive gain, measurement depth, and beam steering were all found to impact the accuracy of measured flow characteristics for linear transducers. Accuracy of the flow measurements made with the curvilinear transducer demonstrated high consistency to changes in receive gain at a constant depth, though were impacted by increasing the measurement depth. CONCLUSIONS: Carefully and consistently selected acquisition and set-up parameters are essential in order to establish a reliable and meaningful QA program.


Assuntos
Ultrassonografia Doppler , Reprodutibilidade dos Testes , Velocidade do Fluxo Sanguíneo/fisiologia , Ultrassonografia , Imagens de Fantasmas
7.
Trop Anim Health Prod ; 55(5): 318, 2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37740068

RESUMO

The aim of this study was to determine if ejaculation modifies the testicular and accessory sex glands' blood flow after ejaculation, and if those changes differ according to the process that leads to ejaculation. Twelve adult Corriedale rams were used and assigned at random to the four procedures that lead to ejaculation: (G1) electroejaculation; (G2) artificial vagina; (G3) transrectal ultrasound-guided massage of the accessory sex glands; (G4) natural mating. Hemodynamic characteristics evaluation of the male reproductive system was conducted immediately before and at 30 and 90 min after ejaculation. The internal iliac artery peak systolic velocity (PSV) decreased (P=0.01) and supratesticular artery PSV increased (P=0.042) 90 min after ejaculation in all groups. In conclusion, ejaculation modifies the reproductive system's blood flow, with slight variations depending on the studied ejaculation methods. Additionally, ejaculation altered the internal iliac and supratesticular arteries PSV, and the supratesticular artery end-diastolic velocity (EDV) in rams. The supratesticular artery PSV was the only studied variable that differed according to the procedure that triggered the ejaculation.


Assuntos
Ejaculação , Sêmen , Masculino , Feminino , Animais , Ovinos , Genitália , Reprodução , Carneiro Doméstico , Hemodinâmica
8.
Res Vet Sci ; 162: 104955, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37459800

RESUMO

In dairy cows, the liver supports the increased nutrient demands of the udder for milk production. Blood flow is key for the transport of these nutrients. This study investigated portal vein blood flow volume (PVBFVol) in relation to daily milk yield (DMY), milk vein blood flow volume (MVBFVol) and body condition parameters of high-producing dairy cows, starting from late lactation, throughout dry period, and consecutive early lactation. Seventeen repeated examinations were performed on 19 Holstein cows and 313 measurement days were finally included. Vein morphology and blood flow were examined via B-mode and spectral Doppler (triplex) ultrasonography, respectively. Body condition parameters recorded were body condition score (BCS), backfat thickness (BFT) measurement with ultrasonography, heart girth circumference (HG) and withers height (WH). Longitudinal relationship of PVBFVol with MVBFVol, DMY, BCS, BFT, HG and WH was analyzed with linear mixed models, with random intercept effects, using restricted cubic splines. A significant increase of 8.28% (p < 0.01) in PVBFVol appeared for every 1 L/min increase in MVBFVol in the univariable model. PVBFVol presented a significant negative association with BCS (p < 0.01) and BFT (p = 0.02), while interaction with production stage was significant, too. PVBFVol significantly increased by 0.38% (p = 0.04) for every 1 kg increase in DMY in the multivariable model. In conclusion, the increased PVBFVol during lactation accompanies the escalation in metabolic activity of the liver and the increased blood circulation through the udder, coping with the udder's escalating nutrient demands for milk synthesis.


Assuntos
Leite , Veia Porta , Feminino , Bovinos , Animais , Leite/metabolismo , Veia Porta/diagnóstico por imagem , Cor , Lactação/fisiologia , Fígado/metabolismo , Dieta
9.
Echocardiography ; 40(5): 440-441, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37026793

RESUMO

Spectral Doppler examination is necessary for full hemodynamic assessment of patients with systolic heart failure. It is fully incorporated into comprehensive echocardiographic examination. In this manuscript, we describe two uncommon findings in patients with established severe left ventricular systolic dysfunction: notched aortic regurgitation and merged mitral regurgitation.


Assuntos
Insuficiência da Valva Aórtica , Insuficiência Cardíaca , Insuficiência da Valva Mitral , Humanos , Ecocardiografia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/diagnóstico por imagem , Ultrassonografia Doppler , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/diagnóstico por imagem
10.
J Ultrasound Med ; 42(9): 1907-1921, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36896465

RESUMO

Imaging pitfalls commonly occur in carotid Doppler ultrasound and may lead to false positive diagnosis of stenosis, missed diagnosis of stenosis, and errors in grading stenosis severity. These pitfalls may result from suboptimal technique and/or patient-specific factors including coexisting cardiovascular pathology, contralateral high-grade stenosis/occlusion, tortuous vessels, tandem lesions, long-segment stenosis, nearly occlusive stenosis, and heavily calcified plaque. Awareness of these pitfalls and careful assessment of the extent of plaque on grayscale and color Doppler as well as analysis of the spectral Doppler waveforms can help avoid misinterpretation of the carotid Doppler examination.


Assuntos
Estenose das Carótidas , Humanos , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/patologia , Constrição Patológica , Artéria Carótida Interna/diagnóstico por imagem , Ultrassonografia Doppler/métodos
11.
J Am Soc Echocardiogr ; 36(5): 447-463, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36754099

RESUMO

Greater interest in imaging the superior vena cava (SVC) in recent years has arisen because of increased focus on disorders of the right heart; the growing use of transvenous access lines, dialysis catheters, and device leads; and the emergence of right ventricular mechanical circulatory support systems via the transcatheter approach. As a low-pressure venous conduit in the right upper mediastinum, the SVC is prone to compression by various pathologic processes, to invasion by malignancies originating in nearby structures, and to complications arising from intraluminal device leads and indwelling catheters. Computed tomography and magnetic resonance venography are the modalities of choice for structural imaging of the SVC. Ultrasound allows a reasonable, yet less detailed anatomic assessment of this venous conduit. Spectral and color Doppler imaging by ultrasound are the most valuable noninvasive tools for the interrogation of SVC blood flow, a marker of the filling pattern of the right heart. Analysis of the velocity, duration, and direction of the Doppler waveforms and their phasic response to respiration makes it possible to distinguish normal from abnormal flow patterns and offers diagnostic insights into disorders that affect right heart function. The aims of this review are to demonstrate the added value SVC imaging provides during transthoracic and transesophageal echocardiographic studies, to outline its usefulness for the detection and evaluation of structural abnormalities, and to detail the role of spectral Doppler imaging in aiding the diagnosis of various disorders that affect the right heart.


Assuntos
Ecocardiografia Transesofagiana , Veia Cava Superior , Humanos , Veia Cava Superior/diagnóstico por imagem , Veia Cava Superior/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Ultrassonografia Doppler
12.
Echocardiography ; 40(2): 96-102, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36607145

RESUMO

OBJECTIVE: To compare the fetal pulmonary artery Doppler indices of pregnant women with autoimmune diseases such as systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), and antiphospholipid syndrome (APS) with healthy pregnant women. METHODS: Thirty-nine pregnancies were included in the case group, 19 of them SLE, 12 with SS, and eight with APS. The gestational age-matched 54 healthy pregnant women were included in the control group. Peak systolic velocity, time-averaged velocity, systolic/diastolic ratio, pulsatility index, resistance index, acceleration time (AT), ejection time (ET), and AT/ET ratio were obtained from pulmonary artery waveform by using spectral Doppler ultrasound. RESULTS: Significantly shorter AT and lower AT/ET ratio were detected in the case group (p = < .001, p = < .001, respectively). The shortening of AT and decreasing of the AT/ET ratio were more predominant in the APS group. However, there was no significant difference between the SLE, SS, and APS groups in fetal pulmonary artery Doppler indices. Also, a moderate correlation was found between maternal disease duration (years) and fetal pulmonary artery AT (r = -.516, p = .001) and AT/ET ratio (r = -.558, p = < .001). CONCLUSION: Fetal pulmonary artery Doppler indices may be affected in maternal autoimmune diseases. Further studies are needed to evaluate fetal pulmonary Doppler indices such as AT and AT/ET ratio to predict neonatal respiratory morbidity and lung maturation in pregnant women with SLE, SS, and APS.


Assuntos
Síndrome Antifosfolipídica , Doenças Autoimunes , Lúpus Eritematoso Sistêmico , Recém-Nascido , Humanos , Gravidez , Feminino , Artéria Pulmonar/diagnóstico por imagem , Estudos de Casos e Controles , Estudos Prospectivos , Ultrassonografia Doppler , Lúpus Eritematoso Sistêmico/complicações , Doenças Autoimunes/complicações , Doenças Autoimunes/diagnóstico por imagem , Pulmão , Ultrassonografia Pré-Natal
13.
Pediatr Surg Int ; 39(1): 38, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36480074

RESUMO

PURPOSE: One of the most important complications of undescended testis (UDT) surgery is testicular atrophy (TA). We aimed to investigate the factors associated with TA in children who underwent orchiopexy for unilateral UDT. METHODS: The data of 215 patients aged < 15 years who underwent orchiopexy for unilateral UDT between November 2019 and September 2022 were analyzed retrospectively. Clinical, radiological, surgical, and follow-up findings were recorded. RESULTS: TA was observed in 29 (13.5%) patients. Mean resistive index (RI) values were 0.44 ± 0.06, 0.54 ± 0.09 and 0.69 ± 0.1 in low, middle and high testicular locations, respectively, and intratesticular RI increased significantly as the testis location raised (p < 0.001). After orchiopexy, the mean testis volume ratio (TVR) increased significantly (0.63 ± 0.13 vs. 0.77 ± 0.15, p < 0.001). Besides, the mean RI values decreased significantly in the postoperative follow-up (0.53 ± 0.12 vs. 0.47 ± 0.13, p < 0.001). In multivariate regression analysis, testicular high location (OR 4.332, 95% CI 2.244-6.578, p = 0.002), deferens-epididymal anomaly (OR 3.134, 95% CI 1.345-7.146, p = 0.021), TVR ≤ 0.5 (OR 5.679, 95% CI 2.953-12.892, p < 0.001) and RI ≥ 0.6 (OR 7.158, 95% CI 3.936-14.569, p < 0.001) were independent predictive factors for TA after orchiopexy. CONCLUSION: Higher testis location, deferens-epididymis anomaly, preoperative TVR and RI were independent predictive factors for TA after orchiopexy in unilateral UDT. The results of the study will help surgeons to predict TA before orchiopexy.


Assuntos
Criptorquidismo , Criança , Masculino , Humanos , Criptorquidismo/diagnóstico por imagem , Criptorquidismo/cirurgia , Estudos Retrospectivos , Atrofia
14.
Ultrasound Int Open ; 8(2): E36-E42, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36408371

RESUMO

Purpose Doppler ultrasound (DUS) is widely used to detect vascular complications after pediatric liver transplantation (LT). This study aimed to assess the moment of first detection of vascular complications with DUS, and to determine the positive predictive value (PPV) of DUS. Materials and Methods Patients aged 0-18 years who underwent LT between 2015 and 2019 were retrospectively included. 92 LTs in 83 patients were included (median age: 3.9 years, interquartile range: 0.7-10.5). Patients underwent perioperative (intra-operative and immediately postoperative) and daily DUS surveillance during the first postoperative week, and at 1, 3, and 12 months. Vascular complications were categorized for the hepatic artery, portal vein, and hepatic veins. DUS findings were compared to surgical or radiological findings during the 1-year follow-up. Results 52 vascular complications were diagnosed by DUS in 35/92 LTs (38%). 15 out of 52 (28.8%) were diagnosed perioperatively, 29/52 (55.8%) were diagnosed on postoperative days 1-7, and 8/52 (15.4%) after day 7. The PPV for all vascular complications diagnosed with DUS was 92.3%. During the 1-year follow-up, 18/19 (94.7%) hepatic artery complications, 19/26 (73.1%) portal vein complications, and 7/7 (100%) hepatic vein complications were diagnosed perioperatively or during the first week. Conclusion The majority of vascular complications during the first year after pediatric LT were diagnosed by DUS perioperatively or during the first week, with a high PPV. Our findings provide important information regarding when to expect different types of vascular complications on DUS, which might improve DUS post-LT surveillance protocols.

15.
Vasc Med ; 27(6): 542-550, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36000474

RESUMO

INTRODUCTION: This study aims to evaluate changes in the arterial spectral Doppler waveform in a canine artery stenosis model. METHODS: Canine femoral artery stenosis models were established in 12 beagle dogs. Doppler waveforms were recorded in the femoral artery preoperatively and postoperatively in the femoral artery and at the ankle after formation of a 50%, 70%, and 90% stenosis or occlusion. Major descriptors for arterial Doppler waveform were used to analyse waveforms. RESULTS: The proportion of multiphasic waveforms proximal to a moderate stenosis decreased compared to normal baseline, although the difference was not statistically significant, whereas the decreases at the stenosis, distal to the stenosis, and at the ankle were significant (p < 0.05). The decreases in arteries with a more severe stenosis or occlusion were significant at all locations (p < 0.05). The proportion of high resistive waveforms decreased significantly at the ankle in the arteries with a moderate stenosis (50%) (p = 0.002), but the decreases proximal to, at, and distal to the stenosis were not significant. The decreases were significant at all locations in the arteries with a more severe stenosis (p < 0.05). The decrease was significant at the ankle in the arteries with an occlusion (p < 0.001) but not significant pre, at, and post an occlusion. CONCLUSIONS: Phasicity and resistance of Doppler waveforms alter in canine femoral arteries with a stenosis. Phasicity change seems more sensitive in response to an arterial stenosis than resistance change. Additional information on arterial resistance could be obtained using end-diastolic ratios, resistive indices, and potentially end-systolic notch velocity measurements.


Assuntos
Artéria Femoral , Humanos , Animais , Cães , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Constrição Patológica
16.
Res Vet Sci ; 150: 131-136, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-35820267

RESUMO

Pulmonary hypertension (PH) triggers hemodynamic changes within the right heart, which may affect hepatic venous flow. The aims of this study were three-fold: to investigate, prospectively, the reliability of the hepatic vein Doppler waveform to diagnose and characterize the magnitude of PH in dogs; to evaluate whether a correlation exists between hepatic venous flow waves and the structural and functional characteristics of the right ventricle (RV); and to determine whether age, gender, body weight, heart rate (HR), heart rhythm and systolic blood pressure affect the hepatic venous waveform pattern. A cross-sectional observational study was carried out in 43 dogs with varying degrees of PH and a control group of 15 healthy dogs. The velocities of the hepatic A, S, V and D spectral waves and the phasic pattern varied according to the severity of PH. Weak to moderate correlations were documented between hepatic vein waves and age, HR, and the structural and functional variables of the RV. A D Wave cut-off of 11.6 cm ∙ s-1 had a sensitivity of 100% and specificity of 35% for differentiation of dogs with severe PH from healthy dogs. Doppler assessment of hepatic venous flow was shown to be a reliable technique for screening dogs for PH.


Assuntos
Doenças do Cão , Hipertensão Pulmonar , Animais , Velocidade do Fluxo Sanguíneo , Estudos Transversais , Doenças do Cão/diagnóstico por imagem , Cães , Veias Hepáticas/diagnóstico por imagem , Veias Hepáticas/fisiologia , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/veterinária , Reprodutibilidade dos Testes , Ultrassonografia Doppler
17.
Emerg Radiol ; 29(2): 371-375, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35013851

RESUMO

PURPOSE: The use of spectral Doppler, peak systolic velocity (PSV), and resistive index (RI) imaging criteria to improve the accuracy of acute appendicitis diagnosis is hypothesized. METHODS: Graded compression ultrasound was performed for suspected patients. The spectral Doppler evaluation was conducted while observing the appendix. A total of 152 patients (82 males and 70 females, ages 4-63 years, mean age of 24.5 years) were examined using the spectral Doppler waveform between 2018 and 2019. RI and PSV values of patients with and without appendicitis were compared to histopathologic findings. SPSS 26 was used to analyze the data, including using descriptive statistics and measures of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: Appendicitis was confirmed in 95 patients (62.5%) and rejected in 57 patients (37.5%). For the diagnosis of appendicitis, the area under the curve (AUC) of receiver operating characteristic (ROC) for RI (0.92 with 95% confidence interval (CI): 0.88, 0.97; P = 0.001) and PSV (0.96, with 95% CI: 0.93, 1.00; P = 0.001) was calculated. The discriminatory RI ≥ 0.49 demonstrated high sensitivity (90.5%) and low specificity (86%), and the discriminatory PSV ≥ 9.6 cm/s had high specificity (94.7%) and sensitivity (94.7%) for appendicitis. CONCLUSION: By incorporating spectral Doppler criteria into routine graded compression ultrasound, the diagnostic accuracy of acute appendicitis was increased. In comparison, high PSV and RI values of the appendix with a cut-off point of 9.6 cm/s and 0.49 differ significantly between positive and negative appendectomy patients.


Assuntos
Apendicite , Adolescente , Adulto , Apendicite/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Ultrassonografia Doppler/métodos , Adulto Jovem
18.
Int J Cardiovasc Imaging ; 37(9): 2717-2726, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33844115

RESUMO

PURPOSE: To establish reference values for the systolic-to-diastolic duration ratio (SDR) of the left ventricle (LV) using spectral Doppler, as well as for the SDR' of the interventricular septum (SEP), LV, and right ventricles (RV) using tissue Doppler of the fetal heart. METHOD: This prospective and cross-sectional study evaluated 374 low-risk singleton pregnancies from 20 to 36 + 6 weeks of gestation. The ventricular filling time (FT) was obtained from LV inflow using spectral Doppler. Tissue Doppler was used to assess the FT of each ventricle by placing the cursor at the atrioventricular junction marked by the mitral and tricuspid valves, respectively. SDR was calculated as the sum of the isovolumic contraction time (ICT) and the ejection time (ET) divided by the sum of the isovolumic relaxation time (IRT) and the ventricular FT. We used regression analysis to obtain the best-fit model polynomial equation for the parameters. The concordance correlation coefficient (CCC) was used to assess intra- and inter-observer reproducibility. RESULTS: SDR and SDR' LV showed a progressive decrease with gestational age (GA); the SDR' RV and SDR' SEP did not show a significant decrease with advancing GA. The SDR LV (r = 0.29, p < 0.0001), SDR' RV (r = 0.21, p < 0.0001), SDR' LV (r = 0.20, p = 0.0001), and SDR' SEP (r = 0.25, p < 0.0001) showed a significant weak positive correlation with fetal heart rate. The inter-observer SDR' SEP measurements demonstrated poor reproducibility (CCC: 0.50), whereas intra-observer SRD LV measurements demonstrated moderate reproducibility (CCC: 0.78). CONCLUSIONS: Reference values for SDR SEP, LV, and RV using spectral and tissue Doppler of fetal heart were established between 20 and 36+6 weeks of gestation.


Assuntos
Ventrículos do Coração , Ultrassonografia Pré-Natal , Estudos Transversais , Feminino , Coração Fetal/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes
19.
J Obstet Gynaecol ; 41(7): 1116-1120, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33427547

RESUMO

We evaluated cervical volume and spectral Doppler parameters: peak systolic velocity (PSV), resistance index (RI) and pulsatility index (PI) in the tumour dominant vessel of 50 patients with cervical squamous cell carcinoma (SCC) staged IIB and IIIB and their changes during treatment. The patients underwent transvaginal Doppler ultrasonography prior to treatment, after external beam radiation therapy (EBRT) and 6 weeks after brachytherapy. Radiotherapy decreased cervical volume and PSV values of the tumour dominant vessel. The PSV values before EBRT in G1 + G2 tumours were higher than in G3 tumours. No correlations between cervical volume, PSV, RI and PI values with disease-free survival (DFS) and overall survival (OS) were found. We concluded, that sonographic assessment of changes in cervical volume of patients with locally advanced cervical SCC during treatment did not allow to predict treatment results. Spectral Doppler parameters PSV, RI and PI of tumour dominant vessel did not predict prognosis for these patients.Impact StatementWhat is already known on this subject? Transvaginal Doppler sonography is considered as a useful diagnostic method in patients with cervical carcinoma. However, despite numerous studies, the value of spectral Doppler parameters in tumour dominant vessel and cervical volume of patients with locally advanced cervical SCC is still not well defined.What the results of this study add? In our prospective study, we found that sonographic assessment of changes in cervical volume of patients with locally advanced cervical SCC during treatment did not allow to predict treatment results and spectral Doppler parameters of tumour dominant vessel did not predict prognosis for these patients.What the implications are of these findings for clinical practice and/or further research? Our study underlines the limited value of spectral Doppler technique in patients with cervical carcinoma. Further research should be focussed on identifying and validating novel prognostic and predictive factors.


Assuntos
Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/diagnóstico por imagem , Ultrassonografia Doppler , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Carcinoma de Células Escamosas/patologia , Colo do Útero/irrigação sanguínea , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tamanho do Órgão , Valor Preditivo dos Testes , Estudos Prospectivos , Fluxo Pulsátil , Taxa de Sobrevida , Carga Tumoral , Neoplasias do Colo do Útero/patologia , Vagina/diagnóstico por imagem , Resistência Vascular
20.
J Emerg Med ; 59(6): 906-910, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32771317

RESUMO

BACKGROUND: Portal venous gas (PVG) is a rarely observed clinical finding generally associated with intestinal ischemia. The proper clinical response to the finding of PVG depends somewhat on the setting in which it is observed. Here we describe a case in which extensive arterial gas emboli (AGE) were encountered during point-of-care ultrasound (POCUS) and subsequent computed tomography (CT) identified PVG secondary to gastric wall ischemia as the likely source. CASE REPORT: A 69-year-old woman with history of metastatic colon cancer presented to the emergency department (ED) with altered mental status. On arrival, she was hypotensive, hypothermic, cachectic, and with abdominal distension. POCUS was performed to evaluate the source of the patient's hypotension, revealing the presence of PVG, as well as gas bubbles in all four chambers of the heart and the aorta. CT scan revealed gastric wall ischemia and confirmed the presence of significant air emboli throughout the portal venous system. Given the overall poor prognosis, the decision was made to forego further chemotherapy or surgery and the patient died later that week while under hospice care. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: AGE can occur in the setting of PVG. This may cause multi-organ failure by disrupting blood flow to organs, especially in patients with circulatory dysfunction, such as shock. Depending on the setting in which it is diagnosed, early detection of PVG may expedite earlier assessments of a patient's negative prognosis or initiation of attempted life-saving treatment. In this case report, we show that POCUS can be used to obtain an expedited diagnosis in a critically ill patient.


Assuntos
Embolia Aérea , Sistemas Automatizados de Assistência Junto ao Leito , Idoso , Embolia Aérea/diagnóstico por imagem , Embolia Aérea/etiologia , Feminino , Humanos , Veia Porta/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ultrassonografia
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