Sentinel Lymph Node Identification in Post Neoadjuvant Chemotherapy Breast Cancer Patients Undergoing Surgical Excision Using Lymphosonography.

OBJECTIVES: This study evaluated the efficacy of lymphosonography in the identification of sentinel lymph nodes (SLNs) in post neoadjuvant chemotherapy patients with breast cancer scheduled to undergo surgical excision. METHODS: Seventy-nine subjects scheduled for breast cancer surgery with SLN excision completed this IRB-approved study, out of which 18 (23%) underwent neoadjuvant chemotherapy before surgery. Subjects underwent percutaneous Sonazoid (GE Healthcare) injections around the tumor area for a total of 1.0 mL. Lymphosonography was performed using CPS on an S3000 HELX scanner (Siemens Healthineers) with a linear probe. Subjects received blue dye and radioactive tracer as part of their standard of care. Excised SLNs were classified as positive or negative for the presence of blue dye, radioactive tracer and Sonazoid. The results were compared between methods and pathology findings. RESULTS: Seventy-two SLNs were surgically excised from 18 subjects, 29 were positive for blue dye, 63 were positive for radioactive tracer and 57 were positive for Sonazoid. Comparison with blue dye showed that both radioactive tracer and lymphosonography achieved an accuracy of 53% (P > .50). Comparison with radioactive tracer showed that blue dye had an accuracy of 53%, while lymphosonography achieved an accuracy of 67% (P < .01). Of the 72 SLNs, 15 were determined malignant by pathology; the detection rate was 47% for blue dye (7/15), 67% for radioactive tracer (10/15) and 100% for lymphosonography (15/15) (P < .001). CONCLUSIONS: Lymphosonography achieved similar accuracy as radioactive tracer and higher accuracy than blue dye for identifying SLNs. The 15 SLNs positive for malignancy were all identified by lymphosonography.

Optimization of duplex velocity criteria for diagnosis of internal carotid artery (ICA) stenosis: A report of the Intersocietal Accreditation Commission (IAC) Vascular Testing Division Carotid Diagnostic Criteria Committee.

Diagnostic criteria to classify severity of internal carotid artery (ICA) stenosis vary across vascular laboratories. Consensus-based criteria, proposed by the Society of Radiologists in Ultrasound in 2003 (SRUCC), have been broadly implemented but have not been adequately validated. We conducted a multicentered, retrospective correlative imaging study of duplex ultrasound versus catheter angiography for evaluation of severity of ICA stenosis. Velocity data were abstracted from bilateral duplex studies performed between 1/1/2009 and 12/31/2015 and studies were interpreted using SRUCC. Percentage ICA stenosis was determined using North American Symptomatic Carotid Endarterectomy Trial (NASCET) methodology. Receiver operating characteristic analysis evaluated the performance of SRUCC parameters compared with angiography. Of 448 ICA sides (from 224 patients), 299 ICA sides (from 167 patients) were included. Agreement between duplex ultrasound and angiography was moderate (κ = 0.42), with overestimation of degree of stenosis for both moderate (50-69%) and severe (⩾ 70%) ICA lesions. The primary SRUCC parameter for ⩾ 50% ICA stenosis of peak-systolic velocity (PSV) of ⩾ 125 cm/sec did not meet prespecified thresholds for adequate sensitivity, specificity, and accuracy (sensitivity 97.8%, specificity 64.2%, accuracy 74.5%). Test performance was improved by raising the PSV threshold to ⩾ 180 cm/sec (sensitivity 93.3%, specificity 81.6%, accuracy 85.2%) or by adding the additional parameter of ICA/common carotid artery (CCA) PSV ratio ⩾ 2.0 (sensitivity 94.3%, specificity 84.3%, accuracy 87.4%). For ⩾ 70% ICA stenosis, analysis was limited by a low number of cases with angiographically severe disease. Interpretation of carotid duplex examinations using SRUCC resulted in significant overestimation of severity of ICA stenosis when compared with angiography; raising the PSV threshold for ⩾ 50% ICA stenosis to ⩾ 180 cm/sec as a single parameter or requiring the ICA/CCA PSV ratio ⩾ 2.0 in addition to PSV of ⩾ 125 cm/sec for laboratories using the SRUCC is recommended to improve the accuracy of carotid duplex examinations.

Imaging approach to COVID-19 associated pulmonary embolism.

The novel coronavirus disease-2019 (COVID-19) illness and deaths, caused by the severe acute respiratory syndrome coronavirus-2, continue to increase. Multiple reports highlight the thromboembolic complications, such as pulmonary embolism (PE), in COVID-19. Imaging plays an essential role in the diagnosis and management of COVID-19 patients with PE. There continues to be a rapid evolution of knowledge related to COVID-19 associated PE. This review summarises the current understanding of prevalence, pathophysiology, role of diagnostic imaging modalities, and management, including catheter-directed therapy for COVID-19 associated PE. It also describes infection control considerations for the radiology department while providing care for patients with COVID-19 associated PE.

Ultrasound for Lower Extremity Deep Venous Thrombosis: Multidisciplinary Recommendations From the Society of Radiologists in Ultrasound Consensus Conference.

Venous ultrasound is the standard imaging test for patients suspected of having acute deep venous thrombosis (DVT). There is variability and disagreement among authoritative groups regarding the necessary components of the test. Some protocols include scanning the entire lower extremity, whereas others recommend scans limited to the thigh and knee supplemented with serial testing. Some protocols use gray-scale ultrasound alone, whereas others include Doppler interrogation. Point-of-care ultrasound is recommended in some settings, and there is heterogeneity of these protocols as well. Heterogeneity of recommendations can lead to errors including incorrect application of guidelines, confusion among requesting physicians, and incorrect follow-up. In October 2016, the Society of Radiologists in Ultrasound convened a multidisciplinary panel of experts to evaluate the current evidence to develop recommendations regarding ultrasound protocols for DVT and the terminology used to communicate results to clinicians. Recommendations were made after open discussion and by unanimous consensus.The panel recommends a comprehensive duplex ultrasound protocol from thigh to ankle with Doppler at selected sites rather than a limited or complete compression-only examination. This protocol is currently performed in many facilities and is achievable with standard ultrasound equipment and personnel. The use of these recommendations will increase the diagnosis of calf DVT and provide better data to explain the presenting symptoms. The panel recommends a single point-of-care protocol that minimizes underdiagnoses of proximal DVT.The panel recommends the term chronic postthrombotic change to describe the residual material that persists after the acute presentation of DVT to avoid potential overtreatment of prior thrombus.Adoption of a single standardized comprehensive duplex ultrasound and a single point-of-care examination will enhance patient safety and clinicians' confidence.

Subdermal Ultrasound Contrast Agent Injection for Sentinel Lymph Node Identification: An Analysis of Safety and Contrast Agent Dose in Healthy Volunteers.

OBJECTIVES: Mapping of the lymphatic chain for identification of the sentinel lymph node (SLN) is an important aspect of predicting outcomes for patients with breast cancer, and it is usually performed as an intraoperative procedure using blue dye and/or radiopharmaceutical agents. Recently, the use of contrast-enhanced ultrasound (CEUS) has been proposed as an alternative imaging technique for this mapping. The objective of this study was to evaluate the use of subdermal administration of the ultrasound (US) contrast agent Sonazoid (GE Healthcare, Oslo, Norway) in terms of patient safety and to select the dose to be used for lymphatic applications in humans. METHODS: This study was performed in 12 female volunteers who received bilateral subdermal injections of Sonazoid (1 or 2 mL dose) in the mid-upper outer quadrant of their breasts at 2 different time points. Contrast-enhanced US examinations were performed 0, 0.25, 0.5, 1, 2, 4, 6, and 24 hours after injection to identify SLNs. RESULTS: Sentinel lymph nodes were identified within the first hour after injection as enhanced structures, and there was no significant difference by dose in the number of SLNs identified (P = .74). The volunteers only had minor adverse experiences (AEs) that resolved completely without intervention by study completion. CONCLUSIONS: The subdermal use of Sonazoid in this study showed only minor local and nonsignificant AEs that were completely resolved without any intervention. Two different doses were compared with no significant differences observed between them. Hence, the lower dose studied (1 mL) was selected for use in future clinical studies.

Accreditation Status and Geographic Location of Outpatient Echocardiographic Testing Facilities Among Medicare Beneficiaries: The VALUE-ECHO Study.

OBJECTIVES: Accreditation of echocardiographic testing facilities by the Intersocietal Accreditation Commission (IAC) is supported by the American College of Cardiology and American Society of Echocardiography. However, limited information exists on the accreditation status and geographic distribution of echocardiographic facilities in the United States. Our study aimed to identify (1) the proportion of outpatient echocardiography facilities used by Medicare beneficiaries that are IAC accredited, (2) their geographic distribution, and (3) variations in procedure type and volume by accreditation status. METHODS: As part of the VALUE-ECHO (Value of Accreditation, Location, and Utilization Evaluation-Echocardiography) study, we examined the proportion of IAC-accredited echocardiographic facilities performing outpatient echocardiography in the 2013 Centers for Medicare and Medicaid Services outpatient limited data set (100% sample) and their geographic distribution using geocoding in ArcGIS (ESRI, Redlands, CA). RESULTS: Among 4573 outpatient facilities billing Medicare for echocardiographic testing in 2013, 99.6% (n = 4554) were IAC accredited (99.7% in the 50 US states and 86.2% in Puerto Rico). The proportion IAC-accredited echocardiographic facilities varied by region, with 98.7%, 99.9%, 99.9%, 99.5%, and 86.2% of facilities accredited in the Northeast, South, Midwest, West, and Puerto Rico, respectively (P < .01, Fisher exact test). Of all echocardiographic outpatient procedures conducted (n = 1,890,156), 99.8% (n = 1,885,382) were performed in IAC-accredited echocardiographic facilities. Most procedures (90.9%) were transthoracic echocardiograms, of which 99.7% were conducted in IAC-accredited echocardiographic facilities. CONCLUSIONS: Almost all outpatient echocardiographic facilities billed by Medicare are IAC accredited. This accreditation rate is substantially higher than previously reported for US outpatient vascular testing facilities (13% IAC accredited). The uniformity of imaging and interpretation protocols from a single accrediting body is important to facilitate optimal cardiovascular care.

Detection of unsuspected pelvic DVTs on abdominopelvic CT scans: a potentially life-saving diagnosis.

Venous thromboembolism (VTE) is a serious common disorder with substantial cost and morbidity to society and can be life threatening in some cases. The majority of VTE is diagnosed on lower extremity ultrasound or CT pulmonary angiography, but some cases of deep venous thrombosis (DVT) may be occasionally diagnosed on CT of the abdomen and pelvis by the alert radiologist. The purpose of our study was to determine the fraction of new/unsuspected DVTs diagnosed on CTAP and the subsequent management and clinical course of these patients. After Institutional Review Board approval, a retrospective search of an institutional imaging database was performed for all cases of DVTs diagnosed on CTs of the abdomen and pelvis. Patients with positive studies were further investigated via clinical chart review for their subsequent management and clinical course. The 90-day mortality of the patients diagnosed with DVT on CTAP was also recorded. Sixty-two patients met the criteria for positive DVT on CTAP. Of these 62 cases, 26 (42 %) were new. Management was substantially changed in 24 out of 26 cases (92 %), most commonly initiation of anticoagulation. The 90-day mortality rate of patients diagnosed with pelvic DVTs on CTAP in our cohort was 21 %. Timely detection of pelvic DVTs can have serious implications for patient management, morbidity, and mortality. The pelvic veins should be included in the search pattern of all radiologists who review CTs of the abdomen and pelvis.

Intersocietal Accreditation Commission Accreditation Status of Outpatient Cerebrovascular Testing Facilities Among Medicare Beneficiaries: The VALUE Study.

OBJECTIVES: Accreditation of cerebrovascular ultrasound laboratories by the Intersocietal Accreditation Commission (IAC) and equivalent organizations is supported by the Joint Commission certification of stroke centers. Limited information exists on the accreditation status and geographic distribution of cerebrovascular testing facilities in the United States. Our study objectives were to identify the proportion of IAC-accredited outpatient cerebrovascular testing facilities used by Medicare beneficiaries, describe their geographic distribution, and identify variations in cerebrovascular testing procedure types and volumes by accreditation status. METHODS: As part of the VALUE (Vascular Accreditation, Location, and Utilization Evaluation) Study, we examined the proportion of IAC-accredited facilities that conducted cerebrovascular testing in a 5% Centers for Medicare and Medicaid Services random Outpatient Limited Data Set in 2011 and investigated their geographic distribution using geocoding. RESULTS: Among 7327 outpatient facilities billing Medicare for cerebrovascular testing, only 22% (1640) were IAC accredited. The proportion of IAC-accredited cerebrovascular testing facilities varied by region (χ(2)[3] = 177.1; P < .0001), with 29%, 15%, 13%, and 10% located in the Northeast, South, Midwest, and West, respectively. However, of the total number of cerebrovascular outpatient procedures conducted in 2011 (38,555), 40% (15,410) were conducted in IAC-accredited facilities. Most cerebrovascular testing procedures were carotid duplex, with 40% of them conducted in IAC-accredited facilities. CONCLUSIONS: The proportion of facilities conducting outpatient cerebrovascular testing accredited by the IAC is low and varies by region. The growing number of certified stroke centers should be accompanied by more accredited outpatient vascular testing facilities, which could potentially improve the quality of stroke care.

Acute nontraumatic splenic infarctions at a tertiary-care center: causes and predisposing factors in 123 patients.

Acute splenic infarcts classically present with left upper quadrant pain, but may be discovered incidentally in many hospitalized patients with otherwise vague complaints. The purpose of our study was to document causes or predisposing conditions in patients found to have acute splenic infarctions on imaging. Following IRB approval, a retrospective review of an imaging database from May 2008 to May 2015 was performed for cases of acute splenic infarctions. The electronic medical record was then reviewed for potential predisposing factors or known causes. Specific note was made of cases with active malignancy, vascular disorders, or inflammatory conditions with an increased risk of vasculopathy. Echocardiogram and electrocardiogram results were reviewed when available. One hundred twenty-three patients with acute splenic infarcts were identified, 65 female and 58 male. The average age was 57 years (range of 22 to 88). Active malignancy was present in 40 patients or 33 %. The most common malignancy in patient with nontraumatic splenic infarctions was pancreatic cancer, present in 16 patients (13 %). In these patients, splenic infarction was due to direct invasion of vessels in the splenic hilum. Acute pancreatitis (severe) was directly responsible for splenic infarction in seven additional cases (6 %). Additional visceral infarcts were present in 18 patients (15 %), most commonly concomitant hepatic or renal infarcts. Documented atrial fibrillation was present in 12 patients, but only 2 cases of left-sided cardiac thrombi were seen on CT (1 atrial, and 1 ventricular thrombus). Eight cases of endocarditis with valvular vegetations were documented on echocardiography (7 %). Splenomegaly was present in 32 patients (26 %) with acute splenic infarction. In patients with nontraumatic splenic infarctions, there appears to be a relatively high association with active malignancy (up to a third of patients). Pancreatic disorders, malignant and inflammatory, also appear to be an important cause of splenic infarction, presumably due to the close proximity of the pancreas to the splenic vessels.

Incidental left atrial and ventricular thrombi on routine CT: outcome and influence on subsequent management at an urban tertiary care referral center.

Incidental left-sided cardiac thrombi are occasionally encountered on CT. This study examined clinical findings and outcome in patients with incidental cardiac thrombi on CT. Our image database was reviewed for incidental left-sided cardiac thrombi on CT. These patients' charts were retrospectively reviewed. Thirty-five patients had incidental left-sided cardiac thrombi on CT, 26 of which were ventricular and 9 atrial. Thirty-two thrombi were unknown prior to the CT, and the radiologist interpretation triggered echocardiography or anticoagulation in most cases. Embolic complications occurred in 14 patients, 4 of which were fatal. Twelve patients had concomitant cancer, 6 of which were newly discovered. Incidental left-sided cardiac thrombi on CT appeared to confer substantial morbidity and mortality in our study. In many cases, the cardiac thrombi were new and led to changes in management. A high rate of malignancy was also noted, which may be related to the hypercoagulable state of malignancy.

Accreditation status and geographic location of outpatient vascular testing facilities among Medicare beneficiaries: the VALUE (Vascular Accreditation, Location & Utilization Evaluation) study.

OBJECTIVE: There is limited information on the accreditation status and geographic distribution of vascular testing facilities in the US. The Centers for Medicare & Medicaid Services (CMS) provide reimbursement to facilities regardless of accreditation status. The aims were to: (1) identify the proportion of Intersocietal Accreditation Commission (IAC) accredited vascular testing facilities in a 5% random national sample of Medicare beneficiaries receiving outpatient vascular testing services; (2) describe the geographic distribution of these facilities. METHODS: The VALUE (Vascular Accreditation, Location & Utilization Evaluation) Study examines the proportion of IAC accredited facilities providing vascular testing procedures nationally, and the geographic distribution and utilization of these facilities. The data set containing all facilities that billed Medicare for outpatient vascular testing services in 2011 (5% CMS Outpatient Limited Data Set (LDS) file) was examined, and locations of outpatient vascular testing facilities were obtained from the 2011 CMS/Medicare Provider of Services (POS) file. RESULTS: Of 13,462 total vascular testing facilities billing Medicare for vascular testing procedures in a 5% random Outpatient LDS for the US in 2011, 13% (n=1730) of facilities were IAC accredited. The percentage of IAC accredited vascular testing facilities in the LDS file varied significantly by US region, p<0.0001: 26%, 12%, 11%, and 7% for the Northeast, South, Midwest, and Western regions, respectively. CONCLUSIONS: Findings suggest that the proportion of outpatient vascular testing facilities that are IAC accredited is low and varies by region. Increasing the number of accredited vascular testing facilities to improve test quality is a hypothesis that should be tested in future research.

Characterizing Sentinel Lymph Node Status in Breast Cancer Patients Using a Deep-Learning Model Compared With Radiologists' Analysis of Grayscale Ultrasound and Lymphosonography.

ABSTRACT: The objective of the study was to use a deep learning model to differentiate between benign and malignant sentinel lymph nodes (SLNs) in patients with breast cancer compared to radiologists' assessments.Seventy-nine women with breast cancer were enrolled and underwent lymphosonography and contrast-enhanced ultrasound (CEUS) examination after subcutaneous injection of ultrasound contrast agent around their tumor to identify SLNs. Google AutoML was used to develop image classification model. Grayscale and CEUS images acquired during the ultrasound examination were uploaded with a data distribution of 80% for training/20% for testing. The performance metric used was area under precision/recall curve (AuPRC). In addition, 3 radiologists assessed SLNs as normal or abnormal based on a clinical established classification. Two-hundred seventeen SLNs were divided in 2 for model development; model 1 included all SLNs and model 2 had an equal number of benign and malignant SLNs. Validation results model 1 AuPRC 0.84 (grayscale)/0.91 (CEUS) and model 2 AuPRC 0.91 (grayscale)/0.87 (CEUS). The comparison between artificial intelligence (AI) and readers' showed statistical significant differences between all models and ultrasound modes; model 1 grayscale AI versus readers, P = 0.047, and model 1 CEUS AI versus readers, P < 0.001. Model 2 r grayscale AI versus readers, P = 0.032, and model 2 CEUS AI versus readers, P = 0.041.The interreader agreement overall result showed κ values of 0.20 for grayscale and 0.17 for CEUS.In conclusion, AutoML showed improved diagnostic performance in balance volume datasets. Radiologist performance was not influenced by the dataset's distribution.

Anatomy Versus Physiology: Is Breast Lymphatic Drainage to the Internal Thoracic (Internal Mammary) Lymphatic System Clinically Relevant?

Approximately 15%-25% of breast lymphatic drainage passes through the internal thoracic (internal mammary) lymphatic system, draining the inner quadrants of the breast. This study aimed to use lymphosonography to identify sentinel lymph nodes (SLNs) in the axillary and internal thoracic lymphatic systems in patients with breast cancer. Seventy-nine patients received subcutaneous ultrasound contrast agent injections around the tumor. Lymphosonography was used to identify SLNs. In 14 of the 79 patients (17.7%), the tumor was located in the inner quadrant of the breast. Lymphosonography identified 217 SLNs in 79 patients, averaging 2.7 SLNs per patient. The 217 identified SLNs in the 79 patients were located in the axillary lymphatic system; none were located in the internal thoracic (internal mammary) lymphatic system, although it was expected in two to four patients (i.e., 4-11 SLNs). These results implied that SLNs associated with breast cancer are predominantly located in the axillary lymphatic system.

Sentinel Lymph Node Identification in Patients With Breast Cancer Using Lymphosonography.

The objective of the work described here was to evaluate the efficacy of lymphosonography in identifying sentinel lymph nodes (SLNs) in patients with breast cancer undergoing surgical excision. Of the 86 individuals enrolled, 79 completed this institutional review board-approved study. Participants received subcutaneous 1.0-mL injections of ultrasound contrast agent (UCA) around the tumor. An ultrasound scanner with contrast-enhanced ultrasound (CEUS) capabilities was used to identify SLNs. Participants were administered with blue dye and radioactive tracer to guide SLN excision as standard-of-care. Excised SLNs were classified as positive or negative for the presence of blue dye, radioactive tracer and UCA, and sent for pathology. Two hundred fifty-two SLNs were excised; 158 were positive for blue dye, 222 were positive for radioactive tracer and 223 were positive for UCA. Comparison with blue dye revealed accuracies of 96.2% for radioactive tracer and 99.4% for lymphosonography (p > 0.15). Relative to radioactive tracer, blue dye had an accuracy of 68.5%, and lymphosonography achieved 86.5% (p < 0.0001). Of 252 SLNs excised, 34 were determined to be malignant by pathology; 18 were positive for blue dye (detection rate = 53%), 23 for radioactive tracer (detection rate = 68%) and 34 for UCA (detection rate = 100%) (p < 0.0001). Lymphosonography was similar in accuracy to radioactive tracer and higher in accuracy than blue dye in identifying SLNs. All 34 malignant SLNs were identified by lymphosonography.

Contrast enhanced ultrasound in the detection of liver metastases: a prospective multi-centre dose testing study using a perfluorobutane microbubble contrast agent (NC100100).

OBJECTIVE: To conduct a dose testing analysis of perfluorobutane microbubble (NC100100) contrast-enhanced ultrasound (CEUS) to determine the optimal dose for detection of liver metastases in patients with extra-hepatic primary malignancy. METHODS: 157 patients were investigated with conventional US and CEUS. CEUS was performed following intravenous administration of perfluorobutane microbubbles (using one dose of either 0.008, 0.08, 0.12 or 0.36 µL/kg body weight). Three blinded off-site readers recorded the number and locations of metastatic lesions detected by US and CEUS. Contrast enhanced CT and MRI were used as the "Standard Of Reference" (SOR). Sensitivity, specificity and accuracy of liver metastasis detection with US versus CEUS, for each dose group were obtained. Dose group analysis was performed using the Chi-square test. RESULTS: 165 metastases were present in 92 patients who each had 1-7 lesions present on the SOR. Sensitivity of US versus CEUS (for all doses combined) was 38% and 67% (p = 0.0001). The 0.12 dose group with CEUS (78%) had significantly higher sensitivity and accuracy (70%) compared to other dose groups (p < 0.05). CONCLUSION: The diagnostic performance of CEUS is dose dependent with the 0.12 µL/kg NC100100 dose group showing the greatest sensitivity and accuracy in detection of liver metastases.

Guidelines for Ultrasound in the Radiology Department During the COVID-19 Pandemic.

The coronavirus disease 2019 is caused by the severe acute respiratory syndrome coronavirus 2. The virus can be spread by close person-to-person contact primarily by respiratory droplets. Given the close proximity of the sonographer or sonologist with the patient during ultrasound examinations, special precautions should be taken to limit the exposure of radiology personnel to patients with coronavirus disease 2019 while still providing optimal patient care. Methods covered in this article include modified workflow, close scrutiny and prioritization of imaging orders, and design of targeted ultrasound protocols. These guidelines summarize the personal experience and insight of multiple colleagues who lead ultrasound sections or are experts in the field.

Influence of Data Parsing on Contrast Enhanced Ultrasound Exams.

RATIONALE AND OBJECTIVES: To explore the influence of data parsing (either selection of frames at set time intervals or by an experienced sonographer) of contrast-enhanced ultrasound (CEUS) exams on physician diagnoses and confidence levels. MATERIALS AND METHODS: Forty consecutive CEUS exams consisting of 10 cases each of indeterminate liver lesions, indeterminate renal lesions, renal cell carcinoma postablation follow-up, and hepatocellular carcinoma postchemoembolization follow-up were selected for analysis. Exams were parsed into sets consisting of five images selected by the performing sonographer and sets containing systematically stored frames every 10, 30, and 60 seconds. Three blinded physicians then reviewed the cine loop and each set of images in randomized order and provided a diagnosis and confidence level. RESULTS: For all clinical applications investigated, no statistically significant differences in diagnostic performance measures or reader confidence were observed between review of the entire cine loop and images selected by the performing sonographer (p > 0.42). Diagnostic performance at 10-second intervals did not show statically significant changes compared to the full cine loop review for all applications (p > 0.18), although reader confidence decreased. At 30-60-second intervals, both diagnostic performance and reader confidence showed statistically significant reduction compared to review of the full cine loop (p < 0.045). CONCLUSIONS: Transfer and review of large cine loops from CEUS exams represent a potential barrier to adoption within the United States workflows. This study demonstrates that images selected by a performing trained sonographer may provide the same value without the review time and data storage costs needed for full cine loop review. Parsing by time points reduced reader confidence and diagnostic performance.

Arterial occlusions increase the risk of in-stent restenosis after vertebral artery ostium stenting.

OBJECTIVE: The study was designed to investigate if vascular occlusion in the internal carotid artery (ICA) or the contralateral vertebral artery (VA) contribute to developing in-stent restenosis (ISR) in patients with vertebral artery ostium stenosis (VAOS). METHODS: 420 consecutive patients treated with VAOS stents (from a population of 8145 patients with VAOS) from January 2013 to December 2014 were analyzed in this retrospective study; 216 with drug eluted stents and 204 with bare metal stents. Based on pre-stent DSA findings, patients were divided into four groups: both carotid and vertebral arteries patent (PAT), ICA occlusion (ICA-OCC), contralateral VA occlusion (CVA-OCC), and combined occlusions (C-OCC). The incidence of ISR (stenosis >50%) was compared between groups using Cox regression analysis. RESULTS: Of the 420 patients, the mean incidence of ISR was 36.4%, with a median 12 months of follow-up (IQR 3-12). Logistic regression analysis showed that drug eluting stent had less ISR than bare metal stent (OR=0.38, 95% CI 0.19 to 0.75, P=0.01). Cox regression analysis showed that CVA-OCC (HR=1.63, P=0.02) and C-OCC (HR=3.30, P=0.001) were risk factors for ISR but not ICA-OCC (P=0.31). In the CVA-OCC and C-OCC groups, in-stent peak systolic velocity (PSV) ≥140 cm/s, 1 day after successful stenting, was associated with subsequent development of ISR (OR=2.81, 95% CI 1.06 to 7.43, P=0.04). CONCLUSION: Contralateral VA occlusion at the time of stenting increased the risk of ISR, especially if stent PSV on day 1 was >140 cm/s. Bare metal stents had more ISR than drug eluting stents.

Canine prostate: contrast-enhanced US-guided radiofrequency ablation with urethral and neurovascular cooling--initial experience.

PURPOSE: To prospectively evaluate in a canine model contrast material-enhanced ultrasonography (US) for guiding and monitoring radiofrequency (RF) ablation of the entire prostate, with urethral and vascular cooling to protect the surrounding structures. MATERIALS AND METHODS: After approval by the institutional animal use and care committee, an RF electrode was used to ablate the entire prostate in 15 dogs. During ablation, pulse-inversion harmonic US was performed by using an endocavitary probe after an intravenous bolus injection (0.04 mL/kg) and infusion (0.015 muL/kg/min) of a US contrast agent. In group 1 (n = 4), no cooling protection was used during ablation. In group 2 (n = 5), urethral and bladder protection was provided by inserting a 12-F catheter infused with cold saline (8 degrees C +/- 4 [standard deviation]) at a rate of 100 mL/min. In group 3 (n = 6), further protection of the neurovascular bundles (NVBs) was provided by infusing cold saline (8 degrees C +/- 4) into the iliac arteries at a rate of 50 mL/min by means of catheterization of the femoral artery. Pathologic findings among the three groups were compared by using the Wilcoxon rank sum test. RESULTS: The average volumes of prostate ablation achieved in the three groups were 96.6%, 91.9%, and 92%. Contrast-enhanced pulse-inversion harmonic US allowed visualization and monitoring of urethral and NVB blood flow during the ablation. Without protection, damage to the urethra and the NVB was demonstrated at both US and pathologic examination. There was highly significant difference in urethral damage between groups with and the group without urethral cooling (P = .002), while intraarterial cooling demonstrated a nonsignificant trend toward a decreased NVB damage (P = .069). CONCLUSION: Contrast-enhanced US can guide RF ablation of the entire prostate. Infusion of cold saline provides effective protection for the urethra during such procedures. The application of intraarterial cooling did not provide a significant improvement in the protection of the NVB in this small study.

Carotid stenosis assessed with a 4-dimensional semiautomated Doppler system.

OBJECTIVE: The purpose of this study was to compare peak systolic velocities (PSVs) and the degree of stenosis obtained with a real-time 3-dimensional (ie, 4-dimensional) Doppler ultrasound scanner (Encore PV; VueSonix Sensors Inc, Wayne, PA) to conventional Doppler ultrasound imaging of the carotid arteries (common [CCA], internal [ICA], and external [ECA]). A secondary goal was to assess Encore volume flow measurements. METHODS: Seventy patients referred for clinical carotid ultrasound participated in this pilot study. Peak systolic velocities of the CCA, ECA, and ICA were obtained bilaterally. The degree of stenosis in the ICA was calculated based on the ICA PSV and ICA/CCA PSV ratio. The Encore detects all 3-dimensional blood flow velocity vectors within 10-s longitudinal volumes of the ICA, ECA, and CCA. On the Encore, a reader determined the centerline of the vessels. The PSV and volume flow were then automatically calculated. The flow measurement error was obtained by comparing the CCA flow to the ICA and ECA flow. Data were compared using linear regression, intraclass correlation coefficients (ICCs), and Bland-Altman analysis. RESULTS: Due to technical difficulties, only 59 patients (323 vessel segments) were available for analysis. There was good agreement between methods for assessing the degree of stenosis based on the ICA PSV (ICC = 0.83; P < .0001) and, to a lesser degree, on the ICA/CCA PSV ratio (ICC = 0.65; P < .0001). Peak systolic velocity measurements obtained with conventional ultrasound and the Encore correlated in all vessels (r >or= 0.32; P < .002), and Bland-Altman analysis showed reasonable variations. The Encore mean volume flow error +/- SD was -4.1% +/- 66.4% and was not biased (P = .57). CONCLUSIONS: A new semiautomated 4-dimensional Doppler device is comparable to conventional Doppler ultrasound for assessment of carotid stenosis.