Feasibility of common carotid artery point of care ultrasound in cardiac output measurements compared to invasive methods

Background

Cardiac output (CO) measurement in the intensive care unit (ICU) requires invasive devices such as the pulmonary artery (PA) catheter or arterial waveform pulse contour analysis (PCA). This study tests the accuracy and feasibility of point of care ultrasound (POCUS) of the common carotid artery to estimate the CO non-invasively and compare it to existing invasive CO measurement modalities.

Methods

Patients admitted to the surgical and cardiothoracic ICU in a tertiary university-affiliated academic center during a 4-month period, with invasive hemodynamic monitoring devices for management, were included in this cohort study. Common carotid artery POCUS was performed to measure the CO and the results were compared to an invasive device.

Results

Intensivists and ICU fellows, using ultrasound of the common carotid artery, obtained the CO measurements. Images of the Doppler flow and volume were obtained at the level of the thyroid gland. Concurrent CO measured via invasive devices was recorded. The patient cohort comprised 36 patients; 52 % were females. The average age was 59 ± 13 years, and 66 % were monitored via PCA device and 33 % via PA catheter. Intraclass correlation coefficient (ICC) analysis demonstrated almost perfect correlation (0.8152) between measurements of CO via ultrasound vs. invasive modalities. The ICC between POCUS and the invasive measurement via PCA was 0.84 and via PA catheter 0.74, showing substantial agreement between the ultrasound and both invasive modalities.

Conclusions

Common carotid artery POCUS offers a non-invasive method of measuring the CO in the critically ill population.     

Diagnostic accuracy of emergency physician performed graded compression ultrasound study in acute appendicitis: a prospective study

Purpose

Accurate early diagnosis of appendicitis can decrease its complications and minimize the mortality, morbidity and costs. This prospective study evaluates the accuracy of bedside emergency physician performed ultrasound study diagnosis in acute appendicitis.

Methods

Patients who were suspicious to have appendicitis based on their clinical findings were included and underwent emergency physician performed ultrasound study. Then they were followed up until the recognition of final diagnosis based on pathology report or identification of an alternative diagnosis. Ultrasound studies were done by post-graduate year three emergency medicine residents or emergency medicine attending physicians who were attended in a 4 h didactic and practical course and with 7.5 MHz linear probe both in longitudinal and axial axes.

Results

Ninety-seven patients were included and analyzed. 27 (27.8 %) of patients had appendicitis according to the results of emergency physicians performed ultrasound studies. 19 (70.37 %) of them had appendicitis according to their pathologic reports too. Forty-three (44.3 %) of patients had appendicitis according to pathology reports. Only 19 (44.18 %) of them were diagnosed by emergency physicians. Emergency physician performed ultrasound study had a sensitivity of 44.18 %, specificity of 85.18 %, positive predictive value of 70.37 %, negative predictive value of 65.71 % and overall accuracy of 67.01 % in diagnosing appendicitis in patients clinically suspicious to have acute appendicitis.

Conclusion

Emergency physician performed bedside ultrasound has an acceptable overall accuracy but its sensitivity is low thus it can help emergency physicians to diagnose the acute appendicitis when used in conjunction with other clinical and para-clinical evaluations but not per se.     

A rare case of sigmoid colon obstruction in patient with ulcerative colitis: role of transabdominal ultrasound-guided biopsy

Introduction

Endometriosis is a common chronic gynaecological disease affecting 10 % of women of reproductive age. Of these 5–12 % may present bowel endometriosis that may be asymptomatic or associated with aspecific symptoms even bowel obstruction.

Case presentation

The case of a 41-year-old woman with history of ulcerative colitis, previous diagnosis of ovarian endometriosis, recurrent abdominal pain not related to the menstrual cycle, with abdominal pain and obstinate constipation for 2 weeks was referred. The patient underwent colonoscopy, transabdominal ultrasound and ultrasound-guided fine-needle biopsy to have a diagnosis.

Discussion

Endometriosis should be considered in the differential diagnosis of every woman of childbearing age who presents with gastrointestinal or abdominal symptoms. As demonstrated in our case and by the burgeoning literature in this field, we believe that the role of transabdominal ultrasound should be reconsidered in the management of abdominal diseases because this examination associated with ultrasound-guided fine-needle biopsy allows, in expert hands, to obtain adequate histological samples avoiding patients to undergo more invasive tests to get a diagnosis.     

Assessment of articular disc displacement of temporomandibular joint with ultrasound

Purpose

To assess pattern of articular disc displacement in patients with internal derangement (ID) of temporomandibular joint (TMJ) with ultrasound.

Materials and methods

Prospective study was conducted upon 40 TMJ of 20 patients (3 male, 17 female with mean age of 26.1 years) with ID of TMJ. They underwent high-resolution ultrasound and MR imaging of TMJ. The MR images were used as the gold standard for calculating sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) of ultrasound for diagnosis of anterior or sideway displacement of the disc.

Results

The anterior displaced disc was seen in 26 joints at MR and 22 joints at ultrasound. The diagnostic efficacy of ultrasound for anterior displacement has sensitivity of 79.3 %, specificity of 72.7 %, accuracy of 77.5 %, PPV of 88.5 %, NPV of 57.1 %, PLR of 2.9 and NLR of 0.34. The sideway displacement of disc was seen in four joints at MR and three joints at ultrasound. The diagnostic efficacy of ultrasound for sideway displacement has a sensitivity of 75 %, specificity of 63.6 %, accuracy of 66.7 %, PPV of 42.8, NPV of 87.5 %, PLR of 2.06, and NLR of 0.39.

Conclusion

We concluded that ultrasound is a non-invasive imaging modality used for assessment of anterior and sideway displacement of the articular disc in patients with ID of TMJ.     

Knee bursitis: a sonographic evaluation

Objective

To evaluate the use of ultrasound for the diagnosis of knee bursitis.

Materials and methods

One-hundred and fifty-eight patients who, from May 2013 to May 2014, had an ultrasound examination of the knee and magnetic resonance imaging (MRI) of the knee during the following month were eligible for the study. The exams were reviewed by two musculoskeletal radiologists with 20 years of experience.

Results

Of these patients, 15 (7 men, 8 women) had bursitis, while 143 (76 men, 67 women) had no bursitis. In evaluating knee bursitis, US, when compared to MRI, correctly identified 13 out of 15 cases of bursitis, showing a sensitivity of 86.67 %, specificity 100 %, and K index of 0.92. Particularly in the suprapatellar bursa, ultrasound showed bursitis in 5 cases versus 7 by MRI (sensitivity of 71.4 %, specificity of 100 %, and K index of 0.82).

Conclusion

Ultrasound can be used as a valuable tool for the evaluation of bursitis of the superficial bursae in patients who cannot undergo MRI.     

Acute abdominal pain in childhood and adolescence: assessing the impact of sonography on diagnosis and treatment

Purpose

To assess the impact of ultrasonography on defining the diagnostic and therapeutic pathways for pediatric patients admitted to the emergency department for acute abdominal pain.

Methods

We performed a retrospective study of all patients aged <16 years with acute abdominal pain who underwent ultrasound examination at our Diagnostic Imaging Department from October 2010 to March 2012. We investigated for each patient the pathway following ultrasound examination and definitive diagnosis. The impact of ultrasonography was defined based on the frequency with which the information resulting from this examination confirmed or denied the diagnostic suspicion made by the emergency physician on the basis of clinical and laboratory findings.

Results

In 497/729 patients (69 %), ultrasound examination did not determine variations in the diagnostic and therapeutic pathways, either because it confirmed the outcome of clinical examination and laboratory tests, or because, even addressing in the opposite direction to these, the emergency physician did not consider its result because of being particularly alarmed or sufficiently reassured by clinical examination and laboratory tests. In the remaining 232/729 cases (31 %), ultrasound examination determined an increase or a reduction of the provided care and attention (subsequently proved justified in the vast majority of cases) in spite of what was initially assessed based on clinical examination and laboratory tests.

Conclusions

The results of our retrospective study demonstrated that ultrasonography was a valuable tool in the management of pediatric patients with acute abdominal pain together with clinical examination and laboratory tests.     

Ultrasound assessment of elbow enthesitis in patients with seronegative arthropathies

Background

Enthesopathy is an evolving area for applied clinical research. MRI is the gold standard in the diagnosis of elbow joint pathology, but recent reports indicate that ultrasound imaging is more sensitive and accurate than MRI in detecting enthesopathy of the heels and knees. Too many patients are under-diagnosed and/or misdiagnosed because the early pathological changes of enthesitis in the different types of seronegative arthropathies are not detected.

Objectives

This study was undertaken to describe the ultrasound features of elbow enthesitis in patients with seronegative arthropathies.

Methods

We studied 38 diseased elbows in 38 patients with spondyloarthropathies (26 men and 12 women, mean age 32 years). All had elbow enthesopathy without typical conventional radiographic findings. Patients with histories of degenerative changes and/or local steroid injections were excluded. An HDI 3000 ATL ultrasound machine was used with a 5–12 MHz linear transducer to examine the affected elbow joints. The elbows of 10 normal healthy individuals were examined as normal controls. The patients were examined in the supine position with the elbow flexed 30°–50°. Longitudinal and transverse scans were obtained of the radiohumeral joint, the ulnahumeral joint, and the olecranon fossa. Two independent observers unaware of the clinical diagnosis read the ultrasound images and assessed the collateral ligaments, intratendinous echogenicity, tendon calcification, tendon thickness, presence of fluid, synovial proliferation, and bony changes. The reliability of the sonographic images was assessed by review of video recordings of the ultrasound examinations.

Results

Ultrasound revealed loss of the fibrillar echopattern (100 %), lack of a homogenous pattern with loss of the tightly packed echogenic dots (100 %), peritendinous edema with flaring of the tendon margins (84.2 %), irregular fusiform tendon thickening (100 %), and hyperechoic intratendinous lesions with ill-defined focal defects (18.4 %). Ultrasound also detected intratendinous calcifications of both the common extensor and common flexor tendons (52.6 %). Bony erosions were seen at the tendon insertions into the lateral epicondyles (13.15 %).

Conclusion

Ultrasonographic features of elbow enthesitis differed from those described in knee and heel enthesitis. Ultrasound clearly showed early signs of tendon calcification, tendon edema, peritendinitis, and bony entheseal erosions. However, in elbow enthesitis the early bone erosion was associated with bone marrow edema, and the common extensor tendon was diffusely thickened. Ultrasound is a reliable, reproducible bedside imaging procedure. It improves the documentation of disease activity, progression, and treatment responses in patients with spondyloarthropathies. We recommend its use for the diagnosis and post-treatment follow-up of patients with enthesitis and seronegative spondyloarthropathies.     

Role of US in evaluating breast implant integrity

Purpose

To assess the diagnostic accuracy and inter-observer variability of ultrasound (US) in recognizing signs of intra or extra-capsular rupture of silicone breast implants by using the magnetic resonance imaging (MRI) findings as the reference standard.

Methods

150 patients for a total of 300 implants underwent breast US and subsequently MR examination searching for signs of intra or extra-capsular rupture. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated for breast US having MRI findings as the reference standard. Cohen’s kappa statistics was used in order to assess inter-observer agreement for US.

Results

170/300 (57 %) implant ruptures were detected at US (intra-capsular n = 110, extra-capsular n = 60). By comparing US findings with MR results, overall sensitivity, specificity, accuracy, PPV, and NPV of 79, 63, 70, 65, and 77 %, respectively, were found for breast US. In case of intra-capsular rupture, sensitivity, specificity, accuracy, PPV, and NPV of 63, 63, 63, 45, and 77 %, respectively, were obtained; 100 % values were found for extra-capsular rupture US diagnosis.

Conclusion

US can be used as the first examination in patients with breast implants. US intra-capsular rupture detection requires further evaluation by MRI; in case of extra-capsular rupture US diagnosis, surgical implant removal could be proposed without further investigations.     

Sonoelastography findings of biceps tendinitis and tendinosis

Objective

The purpose of this study was to evaluate sonoelastography (SE) in the assessment of the long head of biceps tendon (LHBT) in patients with symptoms of biceps tendinitis or tendinosis and in patients without biceps lesion. The findings were compared with those obtained at clinical examination, using ultrasonography (US).

Materials and methods

36 shoulders of 34 consecutively registered patients with clinical symptoms and US findings of biceps tendinitis or tendinosis, and 114 shoulders of 98 patients without biceps lesions were assessed with SE. Transverse and longitudinal images of LHBT were obtained using SE. SE images were evaluated by reviewers using an experimentally proven color grading system.

Results

The transverse images of SE showed a mean sensitivity of 69.4 %, a mean specificity of 95.6 % and a mean accuracy of 89.3 %. Good correlation of conventional ultrasound findings was found (p < 0.001, r = 0.763). The longitudinal images of SE showed a mean sensitivity of 94.4 %, a mean specificity of 92.1 % and a mean accuracy of 92.7 %. Good correlation of conventional ultrasound findings was found (p < 0.001, r = 0.585). Inter-observer reliability of SE was in “almost perfect agreement” with a weighted kappa coefficient of 0.84.

Conclusions

SE has potential to be clinically useful in the detection of the intratendinous and peritendinous alterations of LHBT and has excellent accuracy and excellent correlation with conventional ultrasound findings.     

Joint effusion of the knee: potentialities and limitations of ultrasonography

Purpose

This study aimed at comparing the diagnostic accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) for the detection of joint effusion of the knee.

Methods

For this retrospective study, approbation by the institutional review board was not required, and written informed consent from the patients was waived. One hundred and fifty-eight patients (83 men and 75 women; median age 41.2 years; age range 13–81 years) who underwent US and MRI of the knee were included in the study. The sensitivity and specificity of US with respect to MRI in the evaluation of the effusion of the knee and in each recess were compared.

Results

In evaluating joint effusion of the knee, compared with MRI, US correctly identified 78 of 96 patients with joint effusion, showing a sensitivity of 81.3 % and a specificity of 100 %, with a positive predictive value (PPV) of 100 % and a negative predictive value (NPV) of 77.5 % (p value = 0.001). Various results were obtained comparing ultrasound with MRI, regarding the various recesses.

Conclusion

US showed high specificity and sensitivity in diagnosing knee joint effusion and could be used in patients who cannot undergo MRI.

Electronic supplementary material

The online version of this article (doi:10.1007/s40477-015-0180-3) contains supplementary material, which is available to authorized users.     

LOWER LIMB ASYMMETRIES IN RHYTHMIC GYMNASTICS ATHLETES

Background

Different limb training demands and limb preference may determine anthropometric and muscle force inter-limb asymmetries in Rhythmic Gymnastics (RG) athletes.

Purpose

The purpose of this study was to evaluate the influence of lateral preference of the lower extremity on anthropometric, range of motion, and isokinetic torque measurements of RG athletes.

Study Design

Cross sectional study

Methods

Lower limb anthropometric measurements (girth, estimated anatomical cross-sectional area), hip, knee and ankle range of motion, flexor and extensor isokinetic torques (angular velocities = 60, 180, e 240 °·s⁻¹) and bilateral asymmetry index were evaluated in 11 international level Rhythmic Gymnastics athletes (17.9 ± 4.0 years of age; 9.1 ± 5,1 years of experience; 26.8 ± 6.0 weekly training hours).

Results

The preferred limb showed larger thigh girth and anatomical cross-sectional area, higher ankle dorsiflexor range of motion, higher hip flexor torque at 60 °·s⁻¹ and higher plantarflexor torque at 180 °·s⁻¹ compared to the non-preferred limb.

Conclusions

The observed differences seem to be strictly related to lateral preference and rhythmic gymnastics training.

Levels of Evidence

3     

CEUS in the study of bladder,method, administration and evaluation,a technical note

Purpose

Contrast-enhanced ultrasound (CEUS) is the application of ultrasound contrast agents (UCAs) to traditional medical sonography. The development of UCAs allowed to overcome some of the limitations of conventional B-mode and Doppler ultrasound techniques and enabled the display of the parenchymal microvasculature. Purpose of this paper is to delineate the elements of a solid and science-based technique in the execution of urinary bladder CEUS.

Methods

We describe the technical execution of urinary bladder CEUS and the use of perfusion softwares to perform contrast enhancement quantitative analysis with generation of time–intensity curves from regions of interest.

Results

During CEUS, normal bladder wall shows a wash-in time of 13 s, a time to peak (TTP) >40 s, a signal intensity (SI) <45 % and a wash-out time >80 s; Low-grade urothelial cell carcinoma (UCC) shows a wash-in time of 13 s, a time to peak TTP >28 s, a SI <45 % and a wash-out time of 40 s; High-grade UCC shows a wash-in time of 13 s, a TTP >28 s, a SI >50 % and a wash-out time of 58 s.

Conclusions

CEUS is a useful tool for an accurate characterization of bladder UCC although it has some drawbacks. To avoid misunderstandings, a widely accepted classification and a standardized terminology about the most significant parameters of this application should be adopted in the immediate future.     

Evaluation with contrast ultrasound of the prevalence of splenic infarction in left-sided infective endocarditis

Purpose

To prospectively evaluate the prevalence of the embolization of the spleen in patients with definite left-sided infective endocarditis (IE) using a contrast-enhanced ultrasound (CEUS).

Methods

From March 2012 through September 2013, 18 consecutive patients (9 females and 9 males, aged 21–83 years) evaluated at our hospital and with definite left-sided IE according to the revised Duke criteria were enrolled. All of the patients gave informed written consent and the study was performed in conformity with the ethical guidelines of the Declaration of Helsinki. All of the patients were submitted to a CEUS of the spleen within 10 days after the definite diagnosis of IE. For the CEUS, a blood pool second-generation contrast agent and an ultrasound machine with a contrast harmonic imaging technology were used.

Results

The splenic CEUS showed infarctions in 11 patients (61 %) and resulted positive in the 2 patients with negative echocardiography.

Conclusions

In this study, CEUS of the spleen, a repeatable and low-cost imaging technique, easily allowed the bedside detection of asymptomatic and even tiny infarctions and showed a high rate of embolization in patients with definite left-sided IE. Therefore, in the setting of IE (possible or definite), CEUS of the spleen has the potential to better define or accelerate the diagnosis itself.

Electronic supplementary material

The online version of this article (doi:10.1007/s40477-014-0131-4) contains supplementary material, which is available to authorized users.     

Sonography of the optic nerve sheath beyond the hyperacute stage of intracerebral hemorrhage

Purpose

To evaluate the feasibility and utility of serial measuring of the optic nerve sheath diameter beyond the hyperacute and acute stage of intracerebral hemorrhage (ICH).

Methods

Four patients with extensive ICH in the left basal ganglia were followed using ultrasound (US) and cerebral CT scans.

Results

Optic nerve sheath diameter values assessed beyond the acute stage of ICH showed a high correlation (ρ = 0.84, p = 0.0022) with midline shift of the third ventricle seen on CT scans.

Conclusions

Optic nerve sonography can be useful to evaluate patients with extensive ICH beyond the acute stage and help monitoring clinical evolution in these patients, when ICP monitoring is not feasible.     

The value of superficial parts and endoanal ultrasonography in evaluating pilonidal disease and exclusion of perianal sepsis

Introduction

Pilonidal disease is a benign anorectal inflammatory disease that involves the subcutaneous adipose tissue overlying the sacrococcygeal region.

The aim of the work

The current study aimed to assess the value of preoperative evaluation of pilonidal disease and the exclusion of perianal sepsis using superficial parts ultrasonography and endoanal ultrasound.

Methodology

Referred 30 patients were clinically diagnosed as pilonidal disease, all were examined with superficial parts ultrasonography and if the disease was extending to the perianal region further endoanal US was performed to exclude perianal sepsis.

Results

7 patients showed subcutaneous abscesses and 23 patients showed pilonidal sinus tracts. Among patients with pilonidal sinus tracts, six tracts (26 %) seen as superficially situated, short narrow tracts with straight course, no side branches and with a blind end situated away from the anal canal wall. 2 (9 %) tracts showed vertical orientation and three tracts (13 %) were wide and deeply situated reaching the presacral fascia. 7 cases (30 %) showed branching pilonidal sinus tracts, two cases of them showed more than one external opening. 5 patients (22 %) showed abnormally long tracts seen reaching the perianal region.

Conclusion

Ultrasonography is an available, inexpensive, safe imaging modality that yields a high degree of accuracy in evaluating pilonidal disease and in exclusion of perianal sepsis.     

Transrectal ultrasound guidance for early transurethral recatheterization after radical prostatectomy

Purpose

To study the usefulness of transrectal ultrasound (TRUS) for catheter guidance in cases of early reinsertion after radical prostatectomy (RP).

Methods

Since 2007, we have used TRUS for catheter guidance when early reinsertion after RP is required. A preliminary TRUS examination is done to carefully check the state of the vesicourethral anastomosis. The entire catheter insertion, from bulbar urethra to the bladder, is followed step by step by transrectal ultrasound imaging that tracks, while the probe pushes the catheter through a correct entering line. This prevents the incorrect placement of the catheter across the posterior aspect of the anastomosis in a posterior extravesical place.

Results

Between 2007 and 2011, 2,165 RPs were performed at reference hospital for prostate cancer. Early catheter reinsertion was required for 56 patients (2.6 %). All procedures were successful. The incidence of vesicourethral stricture after long-term follow-up was not different from that of patients without early recatheterization who were operated with RP in the same period of the study (4.4 vs 4.2 %, respectively; p = 0.47).

Conclusions

If early recatheterization is required in patients recently operated with RP, we suggest catheter guidance with TRUS.     

Four-dimensional ultrasound guidance during epidural anaesthesia

Background

Four-dimensional (4D) ultrasound scanning (3D real-time mode) can improve the orientation of the anatomy of the area of interest and navigation by controlling the needle position. The objectives of this study were to identify the optimal technique for navigation and to assess clinically the efficacy of 4D ultrasound navigation for epidural anaesthesia at lower thoracic and lumbar levels.

Design

Single-centre case series study was performed.

Methods

Sixteen patients were included. First, conventional 2D scanning was performed, followed by 4D reconstruction, and the basic tissues with high acoustic impedance (bone structures) and available acoustic windows were determined. Movement of the needle was controlled on the sagittal plane in 2D mode and at the same time in 4D mode (3D real-time mode). To improve the visibility of the needle, the 3D reconstruction was rotated during manipulation.

Results

The 4D scanning mode provided 100 % visibility of compact bone tissues and 93 % visibility of the posterior complex. Needle visualisation strongly depended on the rotation of the reconstructed image with the sensor remaining motionless. The needle was redirected in one patient (7 %) because it was in contact with the vertebral lamina. Dilation of the epidural space during saline injection was observed in five patients (36 %). A change in the puncture level was not required any patients; no complications associated with epidural puncture were observed.

Conclusions

Ultrasound navigation in 4D could improve epidural anaesthesia due to the enhanced spatial orientation of the operator. The technique of “position contrast” should be used for reliable needle visualisation.

Electronic supplementary material

The online version of this article (doi:10.1007/s40477-014-0150-1) contains supplementary material, which is available to authorized users.     

Role of transrectal ultrasound in the diagnosis of extracapsular prostate cancer

Introduction

Transrectal ultrasound (TRUS) has significantly improved the diagnostic rate, nevertheless, the correlation between findings on TRUS and clinically significant prostate cancer (PCa) is not completely understood. The purpose of this study was to evaluate the diagnostic accuracy and utility of preoperative TRUS in patients with PCa to define the sonographic signs of cohesion of the Denonvilliers’ fascia (DF) to prostate capsula (PC) to detect the local advancement of the disease.

Methods

Between April 2010 and May 2013, at our Department of Urology, the clinical anatomy of preoperative regions and excised specimens was reviewed macroscopically for 68 cases of radical retropubic prostatectomy for PCa and compared to ultrasound images obtained by TRUS.

Results

Pathological analysis detected on the surface of the prostate the DF fused with the PC at the midpoint of the prostatic posterior surface in 94 % of the cases, in 4 % the DF remained at a certain distance from PC in this region and in 1 case lateral pelvic fascia fused with PC and little adipose tissue was present between them (P < 0.005). The TRUS allowed a more precise result in terms of tumor extension to DF with a detection rate of 95 %. (P < 0.001).

Conclusion

In our opinion, it is very important to recognize preoperatively the possibility of cancer extracapsular extension to the DF and to the rectum wall, using a simple and low cost examination as TRUS. The knowledge of the fascial structures anatomy around the prostate is necessary to perform a nerve-sparing radical prostatectomy, avoiding excessive bleeding, iatrogenic positive surgical margin, and post-operative complications.     

Quantification of LV function and mass by cardiovascular magnetic resonance: multi-center variability and consensus contours

Background

High reproducibility of LV mass and volume measurement from cine cardiovascular magnetic resonance (CMR) has been shown within single centers. However, the extent to which contours may vary from center to center, due to different training protocols, is unknown. We aimed to quantify sources of variation between many centers, and provide a multi-center consensus ground truth dataset for benchmarking automated processing tools and facilitating training for new readers in CMR analysis.

Methods

Seven independent expert readers, representing seven experienced CMR core laboratories, analyzed fifteen cine CMR data sets in accordance with their standard operating protocols and SCMR guidelines. Consensus contours were generated for each image according to a statistical optimization scheme that maximized contour placement agreement between readers.

Results

Reader-consensus agreement was better than inter-reader agreement (end-diastolic volume 14.7 ml vs 15.2–28.4 ml; end-systolic volume 13.2 ml vs 14.0–21.5 ml; LV mass 17.5 g vs 20.2–34.5 g; ejection fraction 4.2 % vs 4.6–7.5 %). Compared with consensus contours, readers were very consistent (small variability across cases within each reader), but bias varied between readers due to differences in contouring protocols at each center. Although larger contour differences were found at the apex and base, the main effect on volume was due to small but consistent differences in the position of the contours in all regions of the LV.

Conclusions

A multi-center consensus dataset was established for the purposes of benchmarking and training. Achieving consensus on contour drawing protocol between centers before analysis, or bias correction after analysis, is required when collating multi-center results.     

Contrast-enhanced ultrasound with SonoVue in the evaluation of postoperative complications in pediatric liver transplant recipients

Purpose

To evaluate the utility of contrast-enhanced sonography in the study of pediatric liver transplant recipients and its potential impact in reducing the need for invasive diagnostic procedures.

Materials and methods

From October 2002 to December 2003 we performed routine color Doppler ultrasound and contrast-enhanced ultrasound studies on 30 pediatric patients who had undergone liver transplantation. Findings indicative of complications were confirmed with invasive studies (angiography, computed tomography, and PTC).

Results

Contrast-enhanced sonography correctly identified four of the five cases of hepatic artery thrombosis and all those involving the portal (n = 6) and hepatic vein (n = 3) thrombosis. It failed to identify one case of hepatic artery thrombosis characterized by collateral circulation arising from the phrenic artery and the single case of hepatic artery stenosis. The latter was more evident on color Doppler, which revealed a typical tardus parvus waveform. The use of contrast offered no significant advantages in the study of biliary complications although it did provide better visualization of bile leaks.

Conclusions

Contrast-enhanced sonography improves diagnostic confidence and reduces the need for more invasive imaging studies in the postoperative follow-up of pediatric liver transplant recipients.