Optimización de la exploración eco Doppler mediante la manipulación de los controles del equipo (knobology); primera parte / Doppler ultrasound exploration optimization by manipulating the controls of the equipment: knobology; part one

La ecografía Doppler es una modalidad diagnóstica dependiente de un operador indispensable por disponibilidad, eficacia y costes. además de conocimientos anatómicos y clínicos, exige un mínimo conocimiento de sus principios físicos y tecnológicos. Conocer, practicar, ajustar las funciones del eco Doppler de forma ordenada y en función del paciente y de la exploración indicada harán que nuestras exploraciones sean más sencillas, rápidas, seguras y precisas. este artículo de formación intenta repasar y esquematizar cómo ajustar las principales aplicaciones del equipo mediante los botones y controles del dispositivo ("knobology").(AU)

doppler ultrasound is an operator-dependent diagnostic modality, essential due to its availability, efficacy and costs.in addition to anatomical and clinical knowledge, it requires a minimum knowledge of its physical and technologicalprinciples. the knowledge, training, and set up the functions of the duplex scan in a properly way depending onthe patient and kind of exploration, will make our examinations easier, faster, safer, and more precise. this papertries to review and outline how to adjust the main applications of the equipment using the buttons and controlsof the device (knobology).(AU)

Vascular Diagnostic and Surgical Treatments Before Lower Limb Amputations in Patients with Arterial Vascular Diseases: A Population Based Study from 2013 to 2015 in Germany.

OBJECTIVE: Patients with peripheral artery disease (PAD) have an increased risk of lower limb amputation. Given the international wide variance in major amputations, the high mortality rates and follow up costs as well as the significantly reduced quality of life of patients with amputations, vascular diagnostics and vascular surgery treatments are of great importance for lower limb preservation in patients with PAD. This study examines these guideline based procedures in patients before a first lower limb amputation and PAD. METHODS: This was a retrospective longitudinal study. Data from a large German statutory health insurance scheme were examined on patients with first amputation of lower extremities and PAD between 2013 and 2015 (incidence). Pre-defined vascular diagnostic and vascular surgical procedures were considered, as specified by guidelines within inpatient and outpatient care in a defined time before lower limb amputation. RESULTS: The overall estimated incidence of lower extremity amputations in the total population was 0.12% from 2013 to 2015. Of these, 51.7% had PAD; 81.8% of patients received at least one vascular diagnostic measure and 61.0% a vascular surgery procedure before the lower extremity amputation. There were only minor variations in the use of diagnostic or surgical treatments between patients with major and minor amputation. In total, 63.9% of patients had vascular surgery before the incident major amputation compared with 60.0% of patients with a minor amputation. Noticeable regional differences were found ranging from 91% (Berlin) to 67% (Bremen) regarding diagnostic procedures provided before amputation, and from 83% (Hamburg) to 55% (Saxony-Anhalt) regarding vascular surgery before amputations. CONCLUSION: Of patients with PAD, 18.2% did not receive a vascular diagnostic examination before amputation as specified in the guidelines, which reflects an underuse of health services. In one third of patients who did not receive vascular surgery, major amputation probably could have been avoided.

Ultrasound in decompression research: fundamentals, considerations, and future technologies.

It is widely accepted that bubbles are a necessary but insufficient condition for the development of decompression sickness. However, open questions remain regarding the precise formation and behavior of these bubbles after an ambient pressure reduction (decompression), primarily due to the inherent difficulty of directly observing this phenomenon in vivo. In decompression research, information about these bubbles after a decompression is gathered via means of ultrasound acquisitions. The ability to draw conclusions regarding decompression research using ultrasound is highly influenced by the variability of the methodologies and equipment utilized by different research groups. These differences play a significant role in the quality of the data and thus the interpretation of the results. The purpose of this review is to provide a technical overview of the use of ultrasound in decompression research, particularly Doppler and brightness (B)-mode ultrasound. Further, we will discuss the strengths and limitations of these technologies and how new advancements are improving our ability to understand bubble behavior post-decompression.

Effect of fluid strategy on stroke volume, cardiac output, and fluid responsiveness in adult patients undergoing major abdominal surgery: a sub-study of the Restrictive versus Liberal Fluid Therapy in Major Abdominal Surgery (RELIEF) trial.

BACKGROUND: We designed a prospective sub-study of the larger Restrictive versus Liberal Fluid Therapy in Major Abdominal Surgery (RELIEF) trial to measure differences in stroke volume and other haemodynamic parameters at the end of the intraoperative fluid protocols. The haemodynamic effects of the two fluid regimens may increase our understanding of the observed perioperative outcomes. METHODS: Stroke volume and cardiac output were measured with both an oesophageal Doppler ultrasound monitor and arterial pressure waveform analysis. Stroke volume variation, pulse pressure variation, and plethysmographic variability index were also obtained. A passive leg raise manoeuvre was performed to identify fluid responsiveness. RESULTS: Analysis of 105 patients showed that the primary outcome, Doppler monitor-derived stroke volume index, was higher in the liberal group: restrictive 38.5 (28.6-48.8) vs liberal 44.0 (34.9-61.9) ml m-2; P=0.043. Similarly, there was a higher cardiac index in the liberal group: 2.96 (2.32-4.05) vs 2.42 (1.94-3.26) L min-1 m-2; P=0.015. Arterial-pressure-based stroke volume and cardiac index did not differ, nor was there a significant difference in stroke volume variation, pulse pressure variation, or plethysmographic variability index. The passive leg raise manoeuvre showed fluid responsiveness in 40% of restrictive and 30% of liberal protocol patients (not significant). CONCLUSIONS: The liberal fluid group from the RELIEF trial had significantly higher Doppler ultrasound monitor-derived stroke volume and cardiac output compared with the restrictive fluid group at the end of the intraoperative period. Measures of fluid responsiveness did not differ significantly between groups. CLINICAL TRIAL REGISTRATION: ACTRN12615000125527.

Updating the use of the Madrid Sonographic Enthesis Index (MASEI): a systematic review of the literature.

OBJECTIVE: To perform a systematic review of the literature to evaluate the use of the enthesis ultrasound Madrid Sonographic Entesis Index (MASEI) from its publication. METHODS: A systematic search of MEDLINE, EMBASE, and Cochrane Central Register databases was performed. The search strategy was constructed to identify publications containing terms related to enthesis and ultrasound. The only applied filter was studies conducted in humans. One reviewer systematically screened the search. A second reviewer verified the selection. The data extraction was focused on study characteristics, including population and components of the OMERACT filter. RESULTS: Sixty-eight of the 1581 identified studies had used MASEI, including 41 (60%) abstracts and 27 (40%) articles. Of the 27 articles, MASEI was mainly used for spondyloarthritis and related diseases in 12 (44%) articles, followed by both psoriatic arthritis and rheumatoid arthritis in five (19%) articles; however, it was also used in diseases such as Behçet disease, FM, familiar Mediterranean fever, SS, crystal arthropathies and systemic sclerosis. The feasibility of MASEI was reported in three (11%) articles, and the reliability in 12 (44%) with good to excellent values. No article evaluated the responsiveness to treatment. The construct validity of MASEI was assessed using biomarkers in seven (26%) articles, clinical examination in 13 (48%) and imaging procedures (only X-rays) in two (7%). The discriminative validity was assessed in 16 (59%) articles, not only in SpAs. CONCLUSION: MASEI is a feasible, reliable and valid ultrasound score for the study of enthesis in spondyloarthritis, psoriatic arthritis and other diseases.

Implications of habitual endurance and resistance exercise for dynamic cerebral autoregulation.

NEW FINDINGS: What is the central question of this study? Does habitual resistance and endurance exercise modify dynamic cerebral autoregulation? What is the main finding and its importance? To the authors' knowledge, this is the first study to directly assess dynamic cerebral autoregulation in resistance-trained individuals, and potential differences between exercise training modalities. Forced oscillations in blood pressure were induced by repeated squat-stands, from which dynamic cerebral autoregulation was assessed using transfer function analysis. These data indicate that dynamic cerebral autoregulatory function is largely unaffected by habitual exercise type, and further document the systemic circulatory effects of regular exercise. ABSTRACT: Regular endurance and resistance exercise produce differential but desirable physiological adaptations in both healthy and clinical populations. The chronic effect of these different exercise modalities on cerebral vessels' ability to respond to rapid changes in blood pressure (BP) had not been examined. We examined dynamic cerebral autoregulation (dCA) in 12 resistance-trained (mean ± SD, 25 ± 6 years), 12 endurance-trained (28 ± 9 years) and 12 sedentary (26 ± 6 years) volunteers. The dCA was assessed using transfer function analysis of forced oscillations in BP vs. middle cerebral artery blood velocity (MCAv), induced via repeated squat-stands at 0.05 and 0.10 Hz. Resting BP and MCAv were similar between groups (interaction: both P ≥ 0.544). The partial pressure of end-tidal carbon dioxide ( PETCO2 ) was unchanged (P = 0.561) across squat-stand manoeuvres (grouped mean for absolute change +0.6 ± 2.3 mmHg). Gain and normalized gain were similar between groups across all frequencies (both P ≥ 0.261). Phase showed a frequency-specific effect between groups (P = 0.043), tending to be lower in resistance-trained (0.63 ± 0.21 radians) than in endurance-trained (0.90 ± 0.41, P = 0.052) and -untrained (0.85 ± 0.38, P = 0.081) groups at slower frequency (0.05 Hz) oscillations. Squat-stands induced mean arterial pressure perturbations differed between groups (interaction: P = 0.031), with greater changes in the resistance (P < 0.001) and endurance (P = 0.001) groups compared with the sedentary group at 0.05 Hz (56 ± 13 and 49 ± 11 vs. 35 ± 11 mmHg, respectively). The differences persisted at 0.1 Hz between resistance and sedentary groups (49 ± 12 vs. 33 ± 7 mmHg, P < 0.001). These results indicate that dCA remains largely unaltered by habitual endurance and resistance exercise with a trend for phase to be lower in the resistance exercise group at lower fequencies.

Evaluation of Lower Extremities' Vascular Characteristics in Myelomeningocele Patients: A Case-Control Study.

OBJECTIVE: Myelomeningocele (MMC) is the most common neural tube defect. Patients with MMC have multiple risk factors for venous thrombosis, but this complication rarely occurs. This lower rate of venous thrombosis in MMC children could be related to some characteristics of the vessels in the lower extremities. This study aimed at finding explanations for this dilemma. METHODS: A case-control study was designed in the Children's Hospital Medical Center, Tehran considering paraplegic patients with MMC as the case group and nonparaplegic MMC patients as a control group. Doppler ultrasound was performed to evaluate femoral and popliteal arterial and venous properties. RESULTS: Patients aged from 8 months to 12 years were evaluated. The mean diameter of the femoral arteries was 3.73 ± 0.23 and 4.72 ± 0.39 mm among paraplegic and nonparaplegic MMC patients, respectively (p = 0.02). The femoral artery flow was 0.52 ± 0.08 and 0.75 ± 0.06 L/min, respectively in the case and control groups (p = 0.015). The diameters of the femoral veins were 4.85 ± 0.34 and 5.13 ± 0.32 mm in the case and control groups, respectively (p > 0.05). Besides, the blood flows of the case and control groups' femoral veins were 0.27 ± 0.08 and 0.14 ± 0.01 L/min, respectively (p = 0.6). It turned out that lower extremities' arteries in the case group had significantly lower blood flow and diameter compared to those of the control group. However, the same venous properties did not show any significant differences. CONCLUSION: The decreased arterial flow along with the unchanged venous properties leads to less stasis and better drainage of the blood, which in turn might result in a lower incidence of deep vein thrombosis.

Role of imaging techniques in liver veno-occlusive disease diagnosis: recent advances and literature review.

INTRODUCTION: Veno-occlusive-disease (VOD), known also as sinusoidal-obstruction-syndrome (SOS), is one of the main complications of haematopoietic stem cell transplantation and is related to the treatment with pyrrolizidine alkaloids or other toxic agents (chemotherapy for liver-metastasis). Clinical diagnosis using the recent criteria from the European Society for Blood and Marrow Transplantation, is the reference for VOD/SOS diagnosis. However, increasing evidence suggests the emerging role of several imaging methods that could help the clinician in VOD/SOS assessment. Areas covered: This review evaluates the current literature on the various imaging techniques used in VOD/SOS diagnosis in several clinical scenarios. Literature searches were performed using several keywords on MEDLINE/Ovid/In-Process/Cochrane Library/EMBASE and PubMed up to July 2018. Expert commentary: Hepatic-gradient-measurement (HVPG) and contextual transjugular-liver-biopsy are invasive and should always be considered in unclear cases. The main studies revolve around ultrasound with Doppler evaluation, identifying numerous findings suggestive of VOD/SOS. However, their accuracy and validation are still suboptimal and controversial. CT-Scan and MRI have shown encouraging data in other contexts in which VOD/SOS can develop, but studies on the post-HSCT patient are lacking. Elastography techniques measuring liver stiffness (LSM) represent the most recent and promising approach for an accurate and early diagnosis of VOD/SOS. In our view, a multidisciplinary approach to the VOD/SOS diagnosis should be highly encouraged.

Prognostic value of dual imaging stress echocardiography following coronary bypass surgery.

AIMS: To assess the prognostic value of dual imaging stress echocardiography after coronary artery bypass grafting (CABG). Dual imaging stress echocardiography, combining the evaluation of regional wall motion and Doppler echocardiographic derived coronary flow velocity reserve (CFVR) of the left anterior descending artery (LAD), is the state-of-the-art methodology during vasodilatory stress. METHODS AND RESULTS: In a prospective, multicenter, observational study, 349 patients (270 men; 69 ±â€¯9 years; 262 symptomatic) with history of CABG underwent high-dose dipyridamole (0.84 mg/kg over 6 min) stress echocardiography with CFVR evaluation of LAD by Doppler. The composite endpoint of death and myocardial infarction was considered in the survival analysis. Positivity rate with either criteria was 13% in the 262 symptomatic patients with appropriate and 6% in the 87 asymptomatic patients with maybe/rarely appropriate indications on the basis of 2014 American College of Cardiology Foundation guidelines. During a median follow-up of 22 months (1st quartile 8, 3rd quartile 44), there were 56 (16%) events: 21 deaths, and 35 nonfatal myocardial infarctions. At Cox analysis, ischemia at stress echo (HR 4.80, 95% CI 2.69-8.55; p < 0.0001), and CFVR of LAD ≤2 (HR 2.28, 95% CI 1.32-3.95; p = 0.003) were multivariable prognostic predictors. Considering the group with no ischemia, patients with CFVR ≤2 showed 2.5 fold higher yearly hard events as compared to those with CFVR >2 (7.5 vs 2.9%; p = 0.002). CONCLUSIONS: Dual imaging stress echocardiography provides useful prognostic information following CABG. Inducible ischemia and abnormal CFVR are strong and independent prognostic indicators in patients with appropriate and rarely/maybe appropriate indications.

Time-intensity curve analysis of contrast-enhanced ultrasound is unable to differentiate renal dysfunction in the early post-transplant period - a prospective study.

BACKGROUND: Contrast enhanced ultrasonography (CEUS) assessment of kidney allografts mainly focuses on graft rejection. However, studies on delayed graft function (DGF) without acute rejection are still lacking. The aim of this study was to build a time-intensity curve (TIC) using CEUS in non-immunological DGF to understand the utility of CEUS in early transplantation. METHODS: Twenty-eight patients in the short-term postoperative period (<14 days) were divided according to the need for dialysis (early graft function [EGF] and [DGF]) and 37 subjects with longer than 90 days follow-up were divided into creatinine tertiles. Time to peak [TTP] and rising time [RT were compared between groups. RESULTS: EGF and DGF were similar, except for creatinine. In comparison to the late group, medullary TTP and RT were shorter in the early group as well as the delay regarding contrast arrival in the medulla (in relation to cortex) and reaching the medullary peak (in relation to artery and cortex). In the late group, patients with renal dysfunction showed shorter temporal difference to reach medullary peak in relation to artery and cortex. CONCLUSIONS: Although it was not possible to differentiate EGF and DGF using TIC, differences between early and late groups point to blood shunting in renal dysfunction.

What's new in musculoskeletal ultrasound in pediatric rheumatology?

Musculoskeletal ultrasound (MSUS) has become almost indispensable in the rheumatology settings nowadays, allowing early diagnosis, careful guidance during procedures such as joint injections and therapy monitoring. Nonetheless, the applicability of MSUS in pediatric population is still limited. Recently, a standardized MSUS examination procedure in pediatric patients with rheumatic diseases, definitions for synovitis and the sonographic features of joints in healthy children has been developed. Also, important data on age-related  vascularization and ossification of joints in children have been published. Much work still needs to be done in the field. As juvenile idiopathic arthritis seems to be the most common use of MSUS in pediatric rheumatology, specific definitions and assessment techniques for enthesitis, tenosynovitis, bone and cartilage damage in children are very much expected. In this article, we will review briefly the current evidence-based knowledge regarding MSUS potential applications in the pediatric rheumatology clinical practice, along with an overview of the recent information about US appearance of musculoskeletal structures in healthy children.

Association between carotid atheroma and cerebral cortex structure at age 73 years.

OBJECTIVE: To examine the relationship between carotid atherosclerosis and cerebral cortical thickness and investigate whether cortical thickness mediates the association between carotid atheroma and relative cognitive decline. METHODS: We assessed 554 community-dwelling subjects (male/female: 296/258) from the Lothian Birth Cohort 1936 who underwent brain magnetic resonance imaging and carotid Doppler ultrasound studies at age 73 years. The relationship between carotid atherosclerosis markers (internal carotid artery stenosis, intima-media thickness, velocity, pulsatility, and resistivity indexes) and vertex-wide cerebral cortical thickness was examined cross-sectionally, controlling for gender, extensive vascular risk factors (VRFs), and intelligence quotient at age 11 (IQ-11). We also determined the association between carotid stenosis and a composite measure of fluid intelligence at age 73 years. A mediation model was applied to examine whether cortical thickness mediated the relationship between carotid stenosis and cognitive function. RESULTS: A widespread negative association was identified between carotid stenosis (median = 15%) and cerebral cortical thickness at age 73 years, independent of the side of carotid stenosis, other carotid measures, VRFs, and IQ-11. This association increased in an almost dose-response relationship from mild to severe degrees of carotid stenosis, across the anterior and posterior circulation territories. A negative association was also noted between carotid stenosis and fluid intelligence (standardized beta coefficient = -0.151, p = 0.001), which appeared partly (approximately 22%) mediated by carotid stenosis-related thinning of the cerebral cortex. INTERPRETATION: The findings suggest that carotid stenosis represents a marker of processes that accelerate aging of the cerebral cortex and cognition that is in part independent of measurable VRFs. Cortical thinning within the anterior and posterior circulation territories partially mediated the relationship between carotid atheroma and fluid intelligence. Ann Neurol 2018;84:576-587.

Screening for fetal growth restriction and placental insufficiency.

Fetal growth restriction (FGR) continues to be a leading cause of preventable stillbirth and poor neurodevelopmental outcomes in offspring, and furthermore is strongly associated with the obstetrical complications of iatrogenic preterm birth and pre-eclampsia. The terms small for gestational age (SGA) and FGR have, for too long, been considered equivalent and therefore used interchangeably. However, the delivery of improved clinical outcomes requires that clinicians effectively distinguish fetuses that are pathologically growth-restricted from those that are constitutively small. A greater understanding of the multifactorial pathogenesis of both early- and late-onset FGR, especially the role of underlying placental pathologies, may offer insight into targeted treatment strategies that preserve placental function. The new maternal blood biomarker placenta growth factor offers much potential in this context. This review highlights new approaches to effective screening for FGR based on a comprehensive review of: etiology, diagnosis, antenatal surveillance and management. Recent advances in novel imaging methods provide the basis for stepwise multi-parametric testing that may deliver cost-effective screening within existing antenatal care systems.

Trends in the Management of Acute Appendicitis in a Single-Center Quality Register Cohort of 5,614 Patients.

Acute appendicitis is one of the most common reasons for emergency surgery. At Stockholm South General Hospital, information on all patients - 15 years or older - undergoing surgery for acute appendicitis is included in a quality register. Data on surgical method, preoperative imaging, hospital stay, intraoperative findings, and 30-day complications were recorded for each patient. From January 2004 to December 2014, 5,614 consecutive patients were registered. The percentage of patients examined with preoperative imaging increased from 30% in 2004 to 93% in 2014. The use of laparoscopic appendectomy increased from 6 to 79%. Negative appendectomies decreased from 7.5-10 to 1.7%. The mean perforation rate was 28.6%. Some form of postoperative complication occurred in 6.6% of those on whom laparoscopy was performed and 10.5% of those who underwent an open surgery, with a significant difference (p < 0.001) in the rate of surgical site infections (surgical site infections, higher in open cases) but with no difference in the number of deep postoperative abscesses. The overall hospital stay decreased from 2004 to 2014 for perforated and non-perforated appendicitis. The overall 30-day mortality rate was 0.12%. Changes in preoperative imaging and treatment strategy for appendicitis during this period resulted in a lower rate of negative appendectomies with acceptable complication rates and shortened hospital stay.

Prenatal prediction of pulmonary hypoplasia.

Pulmonary hypoplasia, although rare, is associated with significant neonatal morbidity and mortality. Conditions associated with pulmonary hypoplasia include those which limit normal thoracic capacity or movement, including skeletal dysplasias and abdominal wall defects; those with mass effect, including congenital diaphragmatic hernia and pleural effusions; and those with decreased amniotic fluid, including preterm, premature rupture of membranes, and genitourinary anomalies. The ability to predict severe pulmonary hypoplasia prenatally aids in family counseling, as well as obstetric and neonatal management. The objective of this review is to outline the imaging techniques that are widely used prenatally to assess pulmonary hypoplasia and to discuss the limitations of these methods.

Detection of microembolic signals in the common carotid artery using Doppler sonography in the porcine model of acute heart failure treated by veno-arterial extracorporeal membrane oxygenation.

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a method used for the treatment most severe cases of decompensated heart failure. The purpose of this study was to evaluate the risk of the formation of microembolisms during VA-ECMO-based therapy. Heart failure was induced with simultaneous detection of microembolisms and the measurement of blood flow rate in the common carotid artery (CCA) without VA-ECMO (0 l/min) and at the VA-ECMO blood flow rate of 1, 2, 3 and 4 l/min. If embolisms for VA-ECMO 0 l/min and the individual regimes for VA-ECMO 1, 2, 3, 4 l/min are compared, a higher VA-ECMO flow rate is accompanied by a higher number of microembolisms. The final microembolism value at 16 min was for the VA-ECMO flow rate of 0 l/min 0.0 (0, 1), VA-ECMO l/min 7.5 (4, 19), VA-ECMO 2 l/min 12.5 (4, 26), VA-ECMO 3 l/min, 21.0 (18, 57) and VA-ECMO 4 l/min, 27.5 (21, 64). Such a comparison is statistically significant if VA-ECMO 0 vs. 4 l/min p<0.0001, 0 vs. 3 l/min p<0.01 and 1 vs. 4 l/min p<0.01 are compared. The results confirm that high VA-ECMO flow rates pose a risk with regards to the formation of a significantly higher number of microemboli in the blood circulation and that an increase in blood flow rates in the CCA corresponds to changes in the VA-ECMO flow rates.

High frequency ultrasound with color Doppler in dermatology.

Ultrasonography is a method of imaging that classically is used in dermatology to study changes in the hypoderma, as nodules and infectious and inflammatory processes. The introduction of high frequency and resolution equipments enabled the observation of superficial structures, allowing differentiation between skin layers and providing details for the analysis of the skin and its appendages. This paper aims to review the basic principles of high frequency ultrasound and its applications in different areas of dermatology.

High frequency ultrasound with color Doppler in dermatology

Abstract: Ultrasonography is a method of imaging that classically is used in dermatology to study changes in the hypoderma, as nodules and infectious and inflammatory processes. The introduction of high frequency and resolution equipments enabled the observation of superficial structures, allowing differentiation between skin layers and providing details for the analysis of the skin and its appendages. This paper aims to review the basic principles of high frequency ultrasound and its applications in different areas of dermatology.