In the last 30 years, the contrast-to-noise ratio (CNR) has been used to estimate the contrast and lesion detectability in ultrasound images. Recent studies have shown that the CNR cannot be used ...with modern beamformers, as dynamic range alterations can produce arbitrarily high CNR values with no real effect on the probability of lesion detection. We generalize the definition of CNR based on the overlap area between two probability density functions. This generalized CNR (gCNR) is robust against dynamic range alterations; it can be applied to all kind of images, units, or scales; it provides a quantitative measure for contrast; and it has a simple statistical interpretation, i.e., the success rate that can be expected from an ideal observer at the task of separating pixels. We test gCNR on several state-of-the-art imaging algorithms and, in addition, on a trivial compression of the dynamic range. We observe that CNR varies greatly between the state-of-the-art methods, with improvements larger than 100%. We observe that trivial compression leads to a CNR improvement of over 200%. The proposed index, however, yields the same value for compressed and uncompressed images. The tested methods showed mismatched performance in terms of lesion detectability, with variations in gCNR ranging from -0.08 to +0.29. This new metric fixes a methodological flaw in the way we study contrast and allows us to assess the relevance of new imaging algorithms.
Hidradenitis suppurativa (HS) is a chronic inflammatory disease that leads to the formation of nodules, abscesses and fistulas, with the formation of scars and fibrosis, causing significant ...impairment in patient quality of life. The diagnosis is clinical, using scores to classify the severity of the condition; currently the most recommended classification is the International Hidradenitis Suppurativa Severity Scoring System (IHS4). Doppler ultrasound has been used to complement the clinical evaluation of patients with HS. It is possible to observe subclinical lesions that change the staging, the severity of the case, and its treatment, either clinical or surgical. Correct treatment is essential to minimize the consequences of this disease for the patient.
To establish an outpatient protocol for the use of Doppler ultrasound in the care of patients with HS.
A narrative review of the literature was carried out on the use of Doppler ultrasound in patients with hidradenitis suppurativa; a referring protocol and technique orientations for imaging assessment in HS were created.
Recommendation to perform ultrasound evaluation of symptomatic areas eight weeks after using antibiotics and four, 12, and 24 weeks after starting immunobiologicals; apply SOS-HS ultrasound severity classification.
The review did not cover all literature on ultrasound and HS; no systematic review was carried out, but rather a narrative one.
The correct assessment of patients staging must be carried out using dermatological ultrasound to avoid progression to scars and fibrosis, which compromise patients quality of life.
To develop evidence-based recommendations for the use of imaging modalities in primary large vessel vasculitis (LVV) including giant cell arteritis (GCA) and Takayasu arteritis (TAK). European League ...Against Rheumatism (EULAR) standardised operating procedures were followed. A systematic literature review was conducted to retrieve data on the role of imaging modalities including ultrasound, MRI, CT and
F-fluorodeoxyglucose positron emission tomography (PET) in LVV. Based on evidence and expert opinion, the task force consisting of 20 physicians, healthcare professionals and patients from 10 EULAR countries developed recommendations, with consensus obtained through voting. The final level of agreement was voted anonymously. A total of 12 recommendations have been formulated. The task force recommends an early imaging test in patients with suspected LVV, with ultrasound and MRI being the first choices in GCA and TAK, respectively. CT or PET may be used alternatively. In case the diagnosis is still in question after clinical examination and imaging, additional investigations including temporal artery biopsy and/or additional imaging are required. In patients with a suspected flare, imaging might help to better assess disease activity. The frequency and choice of imaging modalities for long-term monitoring of structural damage remains an individual decision; close monitoring for aortic aneurysms should be conducted in patients at risk for this complication. All imaging should be performed by a trained specialist using appropriate operational procedures and settings. These are the first EULAR recommendations providing up-to-date guidance for the role of imaging in the diagnosis and monitoring of patients with (suspected) LVV.
AIM: To evaluate the use of translumenal pancreatography with placement of endoscopic ultrasonography(EUS)-guided drainage of the pancreatic duct.METHODS: This study enrolled all consecutive patients ...between June 2002 and April 2014 who underwent EUSguided pancreatography and subsequent placement of a drain and had symptomatic retention of fluid in the pancreatic duct after one or more previous unsuccessful attempts at endoscopic retrograde cannulation of the pancreatic duct. In all,94 patients underwent 111 interventions with one of three different approaches:(1) EUS-endoscopic retrograde drainage with a rendezvous technique;(2) EUS-guided drainage of the pancreatic duct; and(3) EUS-guided,internal,antegrade drainage of the pancreatic duct.RESULTS: The mean duration of the interventions was 21 min(range,15-69 min). Mean patient age was 54 years(range,28-87 years); the M:F sex ratio was 60:34. The technical success rate was 100%,achieving puncture of the pancreatic duct including pancreatography in 94/94 patients. In patients requiring drainage,initial placement of a drain wassuccessful in 47/83 patients(56.6%). Of these,26 patients underwent transgastric/transbulbar positioning of a stent for retrograde drainage; plastic prostheses were used in 11 and metal stents in 12. A ring drain(antegrade internal drainage) was placed in three of these 26 patients because of anastomotic stenosis after a previous surgical intervention. The remaining 21 patients with successful drain placement had transpapillary drains using the rendezvous technique; the majority(n = 19) received plastic prostheses,and only two received metal stents(covered self-expanding metal stents). The median follow-up time in the 21 patients with transpapillary drainage was 28 mo(range,1-79 mo),while that of the 26 patients with successful transgastric/transduodenal drainage was 9.5 mo(range,1-82 mo). Clinical success,as indicated by reduced or absence of further pain after the EUS-guided intervention was achieved in 68/83 patients(81.9%),including several who improved without drainage,but with manipulation of the access route.CONCLUSION: EUS-guided drainage of the pancreatic duct is a safe,feasible alternative to endoscopic retrograde drainage when the papilla cannot be reached endoscopically or catheterized.
For health professionals, the absence of pulse checked by manual palpation is a primary indicator for initiating chest compressions in patients considered to have cardiopulmonary arrest (CA). ...However, using a pulse check to evaluate perfusion during CA may be associated with some risks of its own. Our objective was to compare the efficiency of cardiac ultrasonography (CUSG), Doppler ultrasonography (DUSG), and manual pulse palpation methods to check the pulse in CA patients.
This study was prospectively performed in 137 patients older than 16 years of age who underwent cardiopulmonary resuscitation (CPR). CUSG, DUSG, and manual pulse palpation were practiced simultaneously as suggested in the relevant guidelines. Findings of the patients were recorded at the first min, at min 15 and at the end of CPR. SPSS 18.0 was used for statistical analysis.
A total of 72.3% (n = 99) of the cardiopulmonary arrest incidents occurred out-of-hospital. CUSG (4.76 ± 2.19, 4.33 ± 2.17, and 3.68 ± 2.14 s), DUSG (9.59 ± 2.37, 8.22 ± 2.86, and 7.60 ± 2.83 s), and manual pulse palpation (10.76 ± 1.03, 9.72 ± 3.01, and 9.29 ± 3.36 s) measurements of the first, second, and last inspections were detected, respectively. The false negative rates (100%, 28%, and 0%) and false positive rates (5.3%, 3.5%, and 0%) of manual pulse palpation the first, second, and last inspections were calculated, respectively, as well.
The use of real-time CUSG during resuscitation provides a substantial contribution to the resuscitation team. CUSG will allow earlier and more accurate detection of pulse than manual pulse palpation and DUSG.
Purpose
To provide clinicians with an evidence-based overview of all topics related to ultrasound vascular access.
Methods
An international evidence-based consensus provided definitions and ...recommendations. Medical literature on ultrasound vascular access was reviewed from January 1985 to October 2010. The GRADE and the GRADE-RAND methods were utilised to develop recommendations.
Results
The recommendations following the conference suggest the advantage of 2D vascular screening prior to cannulation and that real-time ultrasound needle guidance with an in-plane/long-axis technique optimises the probability of needle placement. Ultrasound guidance can be used not only for central venous cannulation but also in peripheral and arterial cannulation. Ultrasound can be used in order to check for immediate and life-threatening complications as well as the catheter’s tip position. Educational courses and training are required to achieve competence and minimal skills when cannulation is performed with ultrasound guidance. A recommendation to create an ultrasound curriculum on vascular access is proposed. This technique allows the reduction of infectious and mechanical complications.
Conclusions
These definitions and recommendations based on a critical evidence review and expert consensus are proposed to assist clinicians in ultrasound-guided vascular access and as a reference for future clinical research.
Therapeutic endoscopic ultrasonography (EUS) procedures using the forward-viewing convex EUS (FV-EUS) have been reviewed based on the articles reported to date. The earliest reported procedure is the ...drainage of pancreatic pseudocysts using FV-EUS. However, the study on drainage of pancreatic pseudocysts focused on showing that drainage is possible with FV-EUS rather than leveraging its features. Subsequently, studies describing the characteristics of FV-EUS have been reported. By using FV-EUS in EUS-guided choledochoduodenostomy, double punctures in the gastrointestinal tract can be avoided. In postoperative modified anatomical cases, using the endoscopic function of FV-EUS, procedures such as bile duct drainage from anastomosis, pancreatic duct drainage from the afferent limb, and abscess drainage from the digestive tract have been reported. When a perpendicular puncture to the gastrointestinal tract is required or when there is a need to insert the endoscope deep into the gastrointestinal tract, FV-EUS is considered among the options.