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Thứ Tư, 25 tháng 2, 2015

Ultrasound +Lab Tests can reliably spot Pediatric Appendicitis


By Erik L. Ridley, AuntMinnie staff writer
February 24, 2015 -- Combining blood tests with sonography findings significantly outperformed ultrasound alone for diagnosing or ruling out pediatric appendicitis, and the combination could also reduce the number of CT scans in children, according to research published online in the Journal of the American College of Surgeons.

In a retrospective study of 845 children seen in the emergency department between 2010 and 2012 for suspected appendicitis, researchers from Boston Children's Hospital found that 51% of ultrasound studies were considered to be equivocal. However, the use of blood test data -- specifically, white blood cell (WBC) count and polymorphonuclear leukocyte differential (PMN%) -- increased negative predictive value (NPV) from 41.9% to 95.8% in these patients, a statistically significant difference (p under 0.001).
In the 18% of patients who had only primary signs of appendicitis on ultrasound, such as increased blood flow or thickening of the appendix wall, the risk of appendicitis increased from 79.1% to 91.3% when the lab studies indicated a bacterial infection. In the 24% of patients who had only secondary signs of appendicitis, such as fat near the appendix, the appendicitis risk climbed from 89.1% to 96.8% when laboratory results were abnormal (JACS, January 30, 2015).
Notably, the researchers said that using the tests could obviate the need for CT. Following guidelines recommending against the use of CT for very high-risk and low-risk categories based on combined ultrasound and laboratory data would have avoided 101 (27.1%) of the 373 CT exams performed during the study period.
"Although our results reflect the experience of a single freestanding children's hospital, the conceptual approach described in this study for characterizing predictive profiles on the basis of laboratory and sonographic data is likely to be generalizable to many, if not all, hospitals that treat appendicitis in the pediatric population," said senior author and pediatric surgeon Dr. Shawn Rangel.
However, instead of suggesting that other institutions adopt their sonographic categories or lab value thresholds for pediatric appendicitis, the researchers advocate that hospitals work with their own radiologists and emergency department physicians to develop a customized approach for categorizing sonographic findings. They should then "develop risk profiles that are tailor-made for their patients after incorporation of their institution's laboratory data," he said in a statement.
"Institutions can use the risk profiles as educational vehicles and clinical guideline decision tools to help emergency department physicians and surgeons avoid unnecessary [CT] scans and admissions for observation for very low-risk patients, and avoid treatment delays in very high-risk patients," Rangel said.

Copyright © 2015 AuntMinnie.com

Thứ Hai, 23 tháng 2, 2015

Superb Micro-Vascular Imaging (SMI)

Ultrasound Doppler mode detects low-grade MSK inflammation
By Erik L. Ridley, AuntMinnie staff writer
February 17, 2015 -- A new Doppler ultrasound technique can provide better visualization of low-grade inflammation in joints and tendons than power Doppler ultrasound, yielding clinical information that often influences patient management, a team of U.K. researchers recently found.  

The technique, called Superb Micro-Vascular Imaging (SMI, Toshiba Medical Systems), offered better visualization of microvasculature, enabling the detection of low-grade inflammation not previously identified with power Doppler, concluded Dr. Adrian Lim, from Imperial College Healthcare National Health Service (NHS) Trust, and colleagues.

"This has significant clinical impact, leading to a change in management in 25% of our patients in this study population," said Lim, who presented the research at the RSNA 2014 meeting in Chicago.

Chủ Nhật, 22 tháng 2, 2015

ElastPQ and LIVER FIBROSIS, [PQ=point quantification]

Liver stiffness values obtained by Elast PQ technique are significantly lower than those obtained by ARFI elastography and future studies are needed to establish the best LS cut-offs assessed by ElastPQ for predicting different liver fibrosis stages.



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ElastPQ (Philips)

from JSUM Ultrasound Elastography Practice Guideline Liver

 Masatoshi Kudo1*, Tsuyoshi Shiina2, Fuminori Moriyasu3, Hiroko Iijima4, Ryosuke Tateishi5, Norihisa Yada1, Kenji Fujimoto6, 7, Hiroyasu Morikawa8, Masashi Hirooka9, Yasukiyo Sumino10, Takashi Kumada11

 A) Introduction
  Name: ElastPQ (PQ: point quantification)
  Equipment: The iU22 xMATRIX ultrasound system (iU: Intelligent Ultrasound)

 ElastPQ is a non-invasive diagnostic tool to measure tissue stiffness using an ARFI-based technology. Immediately after image acquisition, the screen displays the image and measurement results, including the mean and median values and the deviations in kPa or m/s (Fig. 33).
*If measurement reliability is low, 0.00 kPa will be displayed as the result.
    Elastic value E [kPa] is calculated using the equation E = 3ρVs where Vs [m/s] is defined as the       shear wave propagation velocity and ρ as tissue density (whose approximated value in the human       body is 1). 
    An ROI can be placed anywhere but at a depth of uder  8 cm.

B) Indication

 1. Quantitative assessment of liver fibrosis in diffuse liver diseases
 2. Neoplastic lesions of the liver

C) Procedures (including Tips and Tricks)

 1. Perform right intercostal scanning to visualize the liver
 2. Steadily place the probe with minimum compression
 3. Set the ROI with a depth of under 8 cm.
 4. Ask the patient to breath hold (if not possible, ask the patient to breathe as shallowly as possible).
 5. Push the” Update” button for quantification 
 6. The use of a mean value from more than 10 measurements is recommended.

 Approach the right hepatic lobe from the right intercostal space. Avoid the left hepatic lobe because the measurement is affected by cardiac movement. Breath hold without exerting abdominal pressure. The most appropriate ROI is the center of the image, namely, immediately below the probe, and 3–5 cm from the probe surface. Avoid blood vessels, any necrotic areas, the boundary between organs, and areas influenced by cardiac movement (ex. left hepatic lobe). Three frequencies (R1/RP/P1) are available. The measurement sensitivity of areas deep inside the body can be improved by using a lower frequency. 

 D) Results (What does the value mean?)

 ・Healthy liver: 4 kPa (2.5–4.7 kPa, 1–1.5 m/s) 
 ・Mild fibrosis: 7 kPa (4.7–12.0 kPa, 1.5–2.0 m/s) 
 ・Moderate–severe fibrosis: 12 kPa (12.0–21.0 kPa, 2.0–2.5 m/s) 
 ・Severe fibrosis: over 21 kPa (over 2.5 m/s)

E) Limitations

・There is a limit to measurable depth.
・ElastPQ is affected by respiratory and body movement.
・Cardiac movement also affects the system.
・Accuracy of measurement depends on the skills of the examiner.
・Measurement accuracy is generally low at the sides of an image.
・Ribs may cast lateral acoustic shadows.

F) Recommendations

At present, the number of studies using ElastPQ is not large enough to reach a definitive conclusion. We look forward to having more study results in the near future.

The place of musculoskeletal ultrasonography in gout diagnosis

Daniela Fodor et al



Investigation questions

One of the problems in US investigation of gouty patients is which sites to be investigated (only symptomatic joints or structures or more extensive examination) and what findings to be search (MSU deposits, effusion, synovial hypertrophy, vascularisation) in order to have good sensibility and specificity of the method. In a recent published paper by Naredo et al [17] the authors found that US examination of 12 anatomical sites (bilateral radio-carpal joint, first metatarsal head cartilage, talar cartilage, second metacarpal head, knee femoral condyle cartilage, patellar and triceps tendons) for DC sign and hyperechoic aggregates gives the best results for sensitivity and specificity (84.6% and 83.3%, respectively). This approach had high positive and good negative predictive values (92% and 71%, respectively) for diagnosing gout. Peiteado et al [57] studied the presence of six types of lesions in gouty patients: hyperechoic spots in the synovial fluid, HCA, bright stippled aggregates, DC sign, erosions, and the Doppler signal in 17 joints and 8 tendons. They found that the knees and MTP joints are the most frequent affected sites (in 93% of patients) and a six-minute US examination of four joints (knees and the 1st MTPs) allowed the detection of HCA or DC sign in 97% of cases. Clinical diagnosis of gout is sometimes difficult, even if the manifestations are in MTF-1 (classical podagra). Kienhorst et al [58] recently demonstrated that in patients with MTP-1 arthritis the gout was the correct diagnosed only in 77% of cases but the general practitioner supposed gout in 98% of cases. In these cases US examination of the joint could simplify the diagnosis process. This fact was demonstrated by Lamers-Karnebeek et al [59] in patients with monoarthrithis in which 48% of patients had MSU crystals-proven gout. In this cases sensitivity of DC sign and any US abnormality (DC sign, tophi, or snowstorm appearance of the joint effusion) was 77 and 96 %, respectively. The authors considered that the DC sign is an important informative finding for clinician, with positive predictive value of 74 % and negative predictive value of 78 %.




The new US techniques probably will increase the US capacity to detect the crystals aggregates. MicroPure, a new US image processing function designed to improve the visualization of microcalcifications, was used by Yin et al [60] in patients with gout. Significantly more microcalcifications were seen with MicroPure compared to gray scale US and the level of agreement between investigators was consistently improved. The method seems to be useful especially for the cases where the presence of gray scale US artifacts or unspecific findings make difficult the interpretation. The use of different imaging methods (dual energy CT, MRI, positron emission tomography) may improve the description of lesions [61].








 The main question is if there is a really need in clinical practice for such a complex approach. The need for good education and training for identification and interpretation of the US findings encountered in gout was underline by Filippucci et al [62].The authors highlight the necessity for dedicated training-programme to avoid the false positive and false negative results. After 7 days of training the rheumatologists with limited US experience gain satisfactory skills to identify MSU aggregates in different tissues. Due to the lower diagnostic utility of the clinical gouty features (exception tophi and response to colchicine) [63], there is an incremental need for imaging techniques to confirm the clinicians’ suppositions. The place of the US in patients suspected of gout must be clearly defined [59] due to the high numbers of patients presented with monoarthritis. The research agenda concerning the use of US in gouty patients is still busy despite of the recent achievements in this pathology. In conclusion in the assessment of the gouty patients US is an important and valuable tool. For a complete examination and a correct interpretation of the imagines the examiner need to have solid US knowledge about normal and pathological aspects of the musculoskeletal structures. Knowing the specific US aspects of MSU depositions will permit a rapid diagnosis. Moreover, when combining the clinical examination with US scan in patients with suspicion of gout a proper and rapid decisions for the patient management can be taken.


PLEURAL ULTRASOUND




Conclusions






 US is a very important diagnostic method for pleural pathology, providing high resolution images, useful in all kinds of clinical scenarios – emergency, diagnostic and interventional ultrasonography. It is superior to chest radiography for the diagnosis of pneumothorax and characterization of pleural effusions. US represents the best method for guiding fluid aspiration and transthoracic biopsy of pleural-based lesions. It is also a reliable method for evaluating the parietal infiltration of the lung tumors, but CT is superior providing more information concerning all parts of the pleura. The limit of this method is the inability to visualize the mediastinal pleura, and the lesions obscured by subcutaneous emphysema and the bony structures of the thorax – scapulae, sternum and the spine. US can provide useful information for almost all pleural pathology and it should be use more extensively for all these reasons, being also accessible, cheap and widely available for many medical specialties.

Thứ Sáu, 13 tháng 2, 2015

CAROTID PI and CV DISEASE




Discussion
In this population of aging Australian women, the ICA PI is demonstrated to be associated with cardiovascular disease. It was significantly correlated to aortic PWV and the Framingham 10-year cardiovascular risk. The ICA PI was significantly predicted by cardiovascular risk factors including age, systolic blood pressure, MAP, BMI, smoking and diabetes. The CCA PI was also significantly related to the Framingham risk score and femPWV, though this relationship was not as strong as for the ICA. Neither CCA nor ICA PI was a significant predictor of ischaemic heart disease over age and systolic blood pressure. Reasons for the stronger relationship of the ICA PI to cardiovascular risk over the CCA may include the following: 1 The normal cerebral circulation is maintained in a constant flow due to a well-developed system of autoregulation, where acute falls in perfusion pressure can have potentially disastrous consequences to cerebral function.16 It can be expected that arteriosclerotic changes will increase flow impedance and should be readily detectable in the ICA.17 2 Readings taken in the common carotid will be influenced by the external carotid artery, which supplies the high resistance vascular beds of the muscles and skin of the face and scalp. Assessment of the PI of the internal carotid is noninvasive and relatively easy to acquire. Only one patient (0.6%) could not be assessed due to high positioning of the carotid bifurcation. The intra- and inter-operator repeatability of this potential cardiovascular health measure is still to be established at this site. Reports are varied for the reliability of PI measures in other applications including trans-cranial Doppler assessment of the cerebral vessels19 and intrauterine assessment of foetal vessels,20,21 with both intra-operator repeatability and technician experience having a significant impact on results.
 The main limitations of this study include the following: 1 This is a cross-sectional analysis, and it therefore does not imply causality. 2 The delay between evaluation of PWV and PIs approached 2 years in some participants. 3 The rate of ischaemic heart disease was low relative to the population sample size, making estimates of the true effect size and odds ratio or risk measures more unreliable.22 4 We were unable to assess the relationship of PI to the prevalence of stroke as no participants had experienced either an ischaemic or haemorrhagic event.


In summary, the PI, as measured by carotid Doppler ultrasound, was significantly related to the Framingham 10-year cardiovascular risk and aortic stiffening as measured by carotid–femoral PWV. Of the two PIs measured, the ICA had the strongest relationship to cardiovascular risk factors and may relate more closely to cardiovascular disease progression. Neither index significantly contributed to prediction of ischaemic heart disease in this analysis.


Thứ Sáu, 6 tháng 2, 2015

PRP for ROTATOR CUFF TENDINOPATHY: US-Guided INJECTIONS


 PRP has been increasingly used in recent years to treat musculoskeletal injuries such as tendinopathy. While a number of studies have assessed the effectiveness of the therapy, researchers have primarily evaluated the clinical symptoms and functions of the treated patient. Furthermore, the studies have produced ambiguous and sometimes conflicting results, Arrigoni said.
As a result, the Italian team sought to evaluate the effectiveness of ultrasound-guided PRP injection of the supraspinatus tendon and compare it with medical and physical therapy alone. Patients were included in the study if they had a diagnosis of tendinosis or a focal tear of the supraspinatus tendon with a diameter of 1 cm or less. The researchers evaluated the success of each method based on morphological changes as seen on MRI and four years of follow-up.
Half of the 240 patients in the study were treated with ultrasound-guided PRP injection, while the other half received only medical and physical therapy. The hospital's blood transfusion department prepared the PRP. After being given local anesthesia with mepivacaine hydrochloride in the subacromial bursa, patients received one of two PRP injections under ultrasound guidance in the supraspinatus tendon. The second injection was provided 21 days later. Patients were immobilized with a soft brace for three days after injection.
Patients with a history of trauma or surgery during the four-year follow-up period were excluded, Arrigoni noted. MRI exams were performed on each patient before and four years after PRP injection, as well as on the group of patients who received medical and physical therapy.
Based on the MRI results, patients were classified as showing improvement, having stationary findings, or worsening. In addition, all patients were given a clinical and functional evaluation before therapy and after the four-year follow-up period. Pain was assessed using scores based on a visual analogue scale (VAS), while shoulder joint function was evaluated with Constant function scores.

"PRP injection in fact delays the degenerative changes of the tendons, and this is documented by the pain relief and functional improvement," Arrigoni said.