Self-reported skills and self-confidence in point-of-care ultrasound: a cross-sectional nationwide survey amongst Finnish emergency physicians.

BACKGROUND: The use of point-of-care ultrasound (POCUS) is increasing. Numerous investigators have evaluated the learning curves in POCUS, but there are no published studies on how emergency physicians perceive their own competence level with this skill. METHODS: A nationwide survey amongst Finnish emergency physicians was conducted. The respondents reported their use of POCUS and how it has affected their clinical decision-making. The number of POCUS examinations performed was compared to the self-assessed skill level with different applications. Cut-off values were determined for the number of examinations required to acquire a good self-assessed skill level in each POCUS application. The correlation between self-confidence and the self-estimated skill level was analyzed. Several different statistical methods were used, such as Student's t-test, Pearson's correlation test, Loess method and ROC curve analysis. RESULTS: A total of 134 out of 253 Finnish emergency medicine specialists and residents (52%) responded to the survey. The most commonly used POCUS applications were POCUS-assisted procedures, pleural effusion and pneumothorax, inferior vena cava and lower extremity deep venous thrombosis. The initial rate of perceived skill acquisition was very steep with the curve flattening with greater skill and more experience. The number of examinations performed to reach a self-assessed good competence varied from seven to 75 with different applications. The lowest cut-off point for self-assessed good competence was obtained for rapid ultrasound for the shock and hypotension-protocol and the highest for focused cardiac examinations. There was an excellent correlation between self-confidence and the self-assessed skill level. CONCLUSIONS: The Finnish emergency practitioners' self-assessed development of POCUS skills parallels the previously published learning curves of POCUS. The correlation of self-confidence and the self-assessed skill level was found to be excellent. These findings add information on the development of perceived POCUS skills amongst emergency physicians and could complement a formal performance assessment.

Contrast-enhanced ultrasound: a new tool for imaging the superficial lymphatic vessels of the upper limb.

BACKGROUND: Despite the new lymphatic imaging methods, there is still a need for a straightforward method of detecting lymphatic abnormalities. Our goal was to investigate the feasibility of applying a contrast enhanced ultrasound (CEUS) procedure as a new approach for visualising the superficial lymphatic vessels of the upper limb. METHODS: Thirty healthy volunteers were examined with CEUS after bilateral intradermal injection of Sonazoid® contrast agent in distal antebrachium. We registered factors affecting intradermal injections, imaging of the superficial lymphatic vessels and the enhancement time of contrast agent reaching the levels of elbow and axilla. RESULTS: CEUS imaging of superficial lymphatic vessels was successful in 59 of 60 upper limbs (98.3%). Median [interquartile ranges] enhancement times of contrast agent to reach the elbow (right 18 s [11-25], left 15 s [12-25]) and axilla (right 77 s [33-118], left 66 s [42-115]) were equally fast. Successful intradermal injections were found to result in two types of contrast enhancement (strong or moderate), while the enhancement time depended on the type of the successful injection. No major differences in enhancement times were observed related to sex, body mass index, age, or side of the arm. CONCLUSIONS: The superficial lymphatic pathways of the upper limb can be visualised with CEUS imaging. Since enhancement time is dependent on the success of intradermal injections, one must pay attention to the injection technique. Further studies are needed to evaluate the method in patients with lymphatic function disorders such as breast cancer therapy related lymphoedema.

2D-shear wave elastography in the evaluation of suspicious superficial inguinal lymph nodes: Reproducibility and region of interest selection.

PURPOSE: To assess the ability of 2D-Shear wave elastography (2D-SWE) to evaluate its reproducibility, to define the optimal orientation and size of the region of interest (ROI), and to differentiate benign from malignant inguinal lymph nodes (LNs). METHOD: Thirty-two suspicious inguinal LNs from 21 patients were evaluated with 2D-SWE. SWE measurements were obtained in two orthogonal planes. To investigate reproducibility, sensitivity and specificity, circular ROIs with a diameter of 1 mm, 2 mm, 3 mm and 5 mm were placed on the cortex of the LNs. Additionally, one freehand ROI was drawn covering majority of the LN. Two observers performed five sets of SWE measurements for each ROI size. All LNs underwent core needle biopsy or were surgically removed. RESULTS: The 3 mm ROI for Mean-E in axial plane showed high interrater agreement [intraclass correlation coefficient (ICC) 0.899] with the cut-off value of 7.31 kPa resulting in 88.9% sensitivity and 60.9% specificity for differentiating malignant from benign LNs. In benign LNs, mean elasticity of the ROI was lower (7.68 ± 3.82 kPa; range, 3.41-15.40 kPa) compared to the malignant LNs (15.81 ± 10.61 kPa; range, 3.86-36.45 kPa). CONCLUSIONS: The most reproducible way to measure stiffness in inguinal LNs is a 3 mm circular ROI centered on the cortex of the LN in axial plane. Elasticity values were higher in the malignant LNs reflecting the stiffer nature of the metastatic LNs. 2D-SWE offers a noninvasive ultrasonographic tool to assess superficial inguinal lymph nodes with high reproducibility.

Cost-minimization modeling of venous thromboembolism diagnostics: performing limited compression ultrasound in primary health care reduces costs compared to referring patients to a hospital.

BACKGROUND: The aim of this retrospective study was to determine whether diagnosing a deep venous thrombosis (DVT) in primary health care using limited compression ultrasound (LCUS) can save resources compared to referring these patients to hospital. According to the current literature, LCUS is as safe as a standard protocol based on a whole-leg ultrasound (US). METHODS: We created a standardized patient for this cost-analysis model based on 76 patients that were referred to hospital for a suspected DVT. Travel distance to the health care centre and hospital was calculated based on the home address. Hospital costs were acquired from the hospital price list and Finnish legislation. Time spent in the hospital was retrieved from hospital statistics. Time spent in the health care centre and travelling were estimated and monetized based on average salary. The cost of participating physicians attending a US training course was estimated based on the national average salary of a general practitioner as well as the course participation fee. A cost-minimization modeling was performed for this standardized patient comparing the total costs, including private and public costs, of standard and LCUS strategies. RESULTS: The total costs per patient of standard and LCUS pathways were 1151.52€ and 301.94€ [difference 849.59€ (95% CI 800.21€-898.97€, p < 0.001)], respectively. The real-life costs of these strategies, considering that some patients are probably referred to hospital every year and including training costs, are 1151.53€ and 508.69€ [difference 642.84€ (95% CI 541.85€-743.82€)], respectively. CONCLUSION: Using LCUS in diagnosing DVT in primary health care instead of referring these patients to the hospital is shown to save a significant amount of public and private resources.

Teaching limited compression ultrasound to general practitioners reduces referrals of suspected DVT to a hospital: a retrospective cross-sectional study.

BACKGROUND: The aim of this study was to retrospectively determine whether teaching limited compression ultrasound (LCUS) to general practitioners (GP) would reduce the number of patients with a suspected lower extremity DVT referred to a hospital for ultrasound (US) examination. According to the current literature, an LCUS protocol is a safe way to diagnose or exclude lower extremity deep venous thrombosis (DVT) and a good option to radiologist-performed whole-leg ultrasound (US), especially in remote health care units where there may be a limited availability of radiological services. METHODS: Between 2015 and 2016, altogether 13 GPs working in the same primary care unit were trained in LCUS for DVT diagnostics. The number of annual referrals due to a suspected DVT from Saarikka primary care unit to the closest hospital was evaluated before and after training. The incidence of DVT was considered to be constant. Thus, the reduction of referrals was attributed to the fact that these patients were diagnosed and treated in primary health care. Incidence rate ratio of hospital referrals was calculated. As a measure of safety, all patients diagnosed with a pulmonary embolism in the nearest hospital were evaluated to determine if they had undergone LCUS by a GP in primary care. RESULTS: Before training in 2014, there were 60 annual referrals due to a suspected DVT; in 2017, after training, the number was reduced to 16, i.e., a 73.3% decrease. The incidence of referrals decreased from 3.21 to 0.89 per 1000 person-years. (IRR 3.58, 95% CI 2.04-6.66, p < 0.001). No patient with a pulmonary embolism diagnosis had LCUS performed previously, indicating that there were no false negatives, resulting in pulmonary embolism. CONCLUSIONS: Teaching LCUS to GPs can safely reduce the number of patients with a suspected DVT referred to a hospital substantially.

Dynamic contrast-enhanced perfusion parameters in ovarian cancer: Good accuracy in identifying high HIF-1α expression.

BACKGROUND: Hypoxia significantly influences treatment response and clinical outcome in solid tumors. A noninvasive marker for hypoxia will help physicians in treatment planning and encourage the efficient use of hypoxia targeted therapies. The purpose of this study was to investigate whether pharmacokinetic dynamic contrast-enhanced (DCE) perfusion parameters are associated with a specific marker of hypoxia, hypoxia-inducible factor 1 alpha (HIF-1α) in ovarian cancer (OC). MATERIALS AND METHODS: Thirty-eight patients with primary OC were enrolled in this prospective study approved by the local ethical committee. Patients underwent dynamic gadolinium-enhanced 3.0 T MRI as part of their staging investigations. Pharmacokinetic perfusion parameters, including a rate constant for transfer of contrast agent from plasma to extravascular extracellular space (EES) (Ktrans) and a rate constant from EES to plasma (Kep), were measured by drawing two types of regions of interest (ROIs): a large solid lesion (L-ROI) and a solid, most enhancing small area (S-ROI) (NordicICE platform). Tissue samples for immunohistochemical analysis were collected during surgery. Kruskal-Wallis, Mann-Whitney U and Chi-square tests were used in statistical analyses. Receiver Operating Characteristic curve analyzes were done for DCE parameters to discriminate high HIF-1α expression. RESULTS: Pharmacokinetic perfusion parameters Ktrans and Kep were inversely associated with HIF-1α expression (Ktrans L-ROI P = 0.021; Ktrans S-ROI P = 0.018 and Kep L-ROI P = 0.032; Kep S-ROI P = 0.033). Ktrans and Kep showed good accuracy in identifying high HIF-1α expression (AUC = 0.832 Ktrans L-ROI; 0.840 Ktrans S-ROI; 0.808 Kep L-ROI and 0.808 Kep L-ROI). CONCLUSION: This preliminary study demonstrated that pharmacokinetic DCE-MRI perfusion parameters are associated with the hypoxia specific marker, HIF-1α in OC. DCE-MRI may be a useful supplementary tool in the characterization of OC tumors in a staging investigation.

Prognostic value of preoperative dynamic contrast-enhanced magnetic resonance imaging in epithelial ovarian cancer.

OBJECTIVES: To investigate whether semi-quantitative and pharmacokinetic perfusion dynamic contrast-enhanced (DCE) parameters are associated with traditional prognostic factors and can predict clinical outcome in ovarian cancer (OC). METHODS: This prospective study, approved by local ethical committee, enrolled 38 patients with primary OC, 2011-2014. After preoperative DCE-MRI (3.0 T), two observers measured perfusion (Ktrans, Kep, Ve, Vp) and semi-quantitative parameters (area under the curve, peak, time-to-peak) by drawing regions of interest (ROIs) covering the large solid lesion (L-ROI) and the most enhancing small area (S-ROI) (NordicICE platform). Kruskal-Wallis was used to analyze associations between MRI parameters and classified prognostic factors. RESULTS: Mean Ktrans values were higher in high-grade serous OC than in other types (L-ROI, P = 0.041; S-ROI, P = 0.018), and lower mean Ktrans values predicted residual tumor (L-ROI P = 0.030; S-ROI, P = 0.012). Higher minimum Vp values were associated with higher International Federation of Gynecology and Obstetrics (FIGO) stage (S-ROI, P = 0.023).Shorter recurrence-free survival was predicted by higher Ve (minimum L-ROI, P = 0.035; maximum S-ROI, P = 0.046), Vp (maximum S-ROI, P = 0.033), and lower time-to-peak (maximum S-ROI, P = 0.047) in Kaplan-Meier analysis. Multiparametric MRI variables combining DCE and diffusion weighted data were also predictive for survival. CONCLUSION: DCE-MRI parameters may represent imaging biomarkers for predicting tumor aggressiveness and prognosis in OC. Higher Ktrans levels were associated with better results in cytoreductive surgery but with earlier recurrence.

Primary and metastatic ovarian cancer: Characterization by 3.0T diffusion-weighted MRI.

OBJECTIVES: We aimed to investigate whether apparent diffusion coefficients (ADCs) measured by 3.0T diffusion-weighted magnetic resonance imaging (DWI) associate with histological aggressiveness of ovarian cancer (OC) or predict the clinical outcome. This prospective study enrolled 40 patients with primary OC, treated 2011-2014. METHODS: DWI was performed prior to surgery. Two observers used whole lesion single plane region of interest (WLsp-ROI) and five small ROIs (S-ROI) to analyze ADCs. Samples from tumours and metastases were collected during surgery. Immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to measure the expression of vascular endothelial growth factor (VEGF) and its receptors. RESULTS: The interobserver reliability of ADC measurements was excellent for primary tumours ICC 0.912 (WLsp-ROI). Low ADCs significantly associated with poorly differentiated OC (WLsp-ROI P = 0.035). In primary tumours, lower ADCs significantly associated with high Ki-67 (P = 0.001) and low VEGF (P = 0.001) expression. In metastases, lower ADCs (WLsp-ROI) significantly correlated with low VEGF receptors mRNA levels. ADCs had predictive value; 3-year overall survival was poorer in patients with lower ADCs (WLsp-ROI P = 0.023, S-ROI P = 0.038). CONCLUSION: Reduced ADCs are associated with histological severity and worse outcome in OC. ADCs measured with WLsp-ROI may serve as a prognostic biomarker of OC. KEY POINTS: • Reduced ADCs correlate with prognostic markers: poor differentiation and high Ki-67 expression • ADCs also significantly correlated with VEGF protein expression in primary tumours • Lower ADC values are associated with poorer survival in ovarian cancer • Whole lesion single plane-ROI ADCs may be used as a prognostic biomarker in OC.

[Axillary ultrasound for a breast cancer patient and changing international treatment practices]. / Rintasyöpäpotilaan kainalon kaikukuvaus ja muuttuvat kansainväliset hoitokäytännöt.

INTRODUCTION: We explored the effects of novel treatment practices on radiological examinations of the axilla in Finland. PATIENTS AND METHODS: Axillary ultrasound was performed for 178 new breast cancer patients preoperatively. A core biopsy was taken from the suspected lymph nodes, and the finding was compared with the postoperative results. RESULTS: Ultrasound in combination with the core biopsy detects 61.6% of the macrometastases. Ultrasound detected almost all axilla having a high tumor burden. CONLUSIONS: Preoperative axillary ultrasound and core biopsy for suspected lymph nodes before the operation is still recommended for all breast cancer patients. Frozen section examination of the sentinel lymph node can be omitted if preoperatively the primary tumour is unifocal, less than 15mm and the axillary ultrasound finding negative.

Diffusion-Weighted Imaging in 3.0 Tesla Breast MRI: Diagnostic Performance and Tumor Characterization Using Small Subregions vs. Whole Tumor Regions of Interest.

INTRODUCTION: Apparent diffusion coefficient (ADC) values are increasingly reported in breast MRI. As there is no standardized method for ADC measurements, we evaluated the effect of the size of region of interest (ROI) to diagnostic utility and correlation to prognostic markers of breast cancer. METHODS: This prospective study was approved by the Institutional Ethics Board; the need for written informed consent for the retrospective analyses of the breast MRIs was waived by the Chair of the Hospital District. We compared diagnostic accuracy of ADC measurements from whole-lesion ROIs (WL-ROIs) to small subregions (S-ROIs) showing the most restricted diffusion and evaluated correlations with prognostic factors in 112 consecutive patients (mean age 56.2±11.6 years, 137 lesions) who underwent 3.0-T breast MRI. RESULTS: Intra- and interobserver reproducibility were substantial (κ = 0.616-0.784; Intra-Class Correlation 0.589-0.831). In receiver operating characteristics analysis, differentiation between malignant and benign lesions was excellent (area under curve 0.957-0.962, cut-off ADC values for WL-ROIs: 0.87×10-3 mm2s-1; S-ROIs: 0.69×10-3 mm2s-1, P<0.001). WL-ROIs/S-ROIs achieved sensitivities of 95.7%/91.3%, specificities of 89.5%/94.7%, and overall accuracies of 89.8%/94.2%. In S-ROIs, lower ADC values correlated with presence of axillary metastases (P = 0.03), high histological grade (P = 0.006), and worsened Nottingham Prognostic Index Score (P<0.05). In both ROIs, ADC values correlated with progesterone receptors and advanced stage (P<0.01), but not with HER2, estrogen receptors, or Ki-67. CONCLUSIONS: ADC values assist in breast tumor characterization. Small ROIs were more accurate than whole-lesion ROIs and more frequently associated with prognostic factors. Cut-off values differed significantly depending on measurement procedure, which should be recognized when comparing results from the literature. Instead of using a whole lesion covering ROI, a small ROI could be advocated in diffusion-weighted imaging.

Contrast-enhanced ultrasound -guided axillary lymph node core biopsy: Diagnostic accuracy in preoperative staging of invasive breast cancer.

OBJECTIVES: To evaluate accuracy of contrast enhanced ultrasound (CEUS)-sentinel procedure followed by core biopsy (CB) and marking in patients with breast cancer. To compare the axillary metastatic tumour burden in patients with positive vs. negative CB results. METHODS: Two radiologists in our tertiary care hospital performed axillary CEUS sentinel procedures on consecutive US node negative breast cancer patients. The first enhancing lymph node (LN) was core biopsied and marked with a breast coil. The results were compared to final histopathology. We analysed the diagnostic performance of CEUS CB and its ability to detect patients with higher axillary burden (>2 metastasis). RESULTS: During the study period between January 2013 and December 2014, altogether 54 patients (mean age 60.4 years) were included in the statistical analysis. The sensitivity for CEUS CB was 66.7%, specificity 100%, PPV 100%, NPV 93.8% and overall accuracy 94.4%. The method correctly recognised all the axillae with higher tumour burdens (sensitivity 100%, N=3) and 59.3% of coils marking the LNs were discovered. CONCLUSION: CEUS -guided axillary CB proved to be feasible and accurate procedure with moderate sensitivity and it clearly identified the higher axillary tumour burden. The coil marking of LNs as used cannot be recommended. In clinical routine, CEUS procedure might be recommended in selective patient populations.

Very low mammographic breast density predicts poorer outcome in patients with invasive breast cancer.

OBJECTIVES: To examine the prognostic value of mammographic breast density (MBD) and mammographic features and their relationship with established prognostic factors in patients with invasive breast cancer. METHODS: Mammographic characteristics of 270 patients were analyzed. MBD was classified according to percentile density (<5%, 5-10%, 10-25%, 25-50%, 50-75%, >75%) and further categorized into very low density (VLD; <10%), low density (LOD; <25%) and mixed density (MID; >25%). Mammographic features were compared with established prognostic factors and patient outcomes while correcting for possible confounders. RESULTS: MBD was inversely associated with tumour grade (p = 0.019). Patients with LOD breasts had worse prognoses compared to those with MID breasts (disease-free survival 74.7% vs. 84.8%, p = 0.048; overall survival 75.3% vs. 90.2%, p = 0.003). Patients with VLD breasts showed the strongest significance compared to the remaining patients, even after adjusting for age, body mass index, and menopausal status. No other mammographic feature was prognostically significant. In Cox regression analysis, VLD proved to be an independent, poor prognostic feature (hazard ratio = 3.275; p < 0.001). CONCLUSION: In patients with newly diagnosed breast cancer, very low MBD proved to be an independent prognostic feature, associated with higher tumour grade and predicted worse survival even after correcting for possible confounders. KEY POINTS: • Percentile mammographic breast density was associated with patient prognosis. • Very low density proved to be an independent poor prognostic factor. • Only patients with densities <10% displayed this difference in survival. • Mammographic breast density was inversely associated with histological tumour grade.

Preoperative axillary staging with 3.0-T breast MRI: clinical value of diffusion imaging and apparent diffusion coefficient.

The axillary staging in newly diagnosed breast cancer is under major evolution. The aims of this study were to define the diagnostic performance of 3.0-T diffusion-weighted imaging (DWI) in the detection of axillary metastases in newly diagnosed breast cancer, to assess apparent diffusion coefficients (ADCs) for histopathologically confirmed metastatic lymph nodes in a clinical setting. Altogether 52 consecutive breast cancer patients underwent magnetic resonance imaging and DWI in addition to axillary ultrasound. ADCs of axillary lymph nodes were analysed by two breast radiologists and ultrasound-guided core biopsies were taken. In a separate reading by one radiologist two types of region of interests were used for a smaller group of patients. Altogether 56 axillae (121 lymph nodes) were included in the statistical analysis. Metastatic axillae (51.8%) had significantly lower ADCs (p<0.001). Mean ADCs were 0.663-0.676 x 10(-3) mm2/s for the histologically confirmed metastatic LNs and 1.100-1.225 x 10(-3) mm2/s for the benign. The sensitivity, specificity, and accuracy of DWI were 72.4%, 79.6%, and 75.9%, respectively with threshold ADC 0.812 x 10(-3) mm2/s. Region of interest with information on the minimum value increased the diagnostic performance (area under the curve 0.794 vs. 0.619). Even though ADCs are significantly associated with histopathologically confirmed axillary metastases the diagnostic performance of axillary DWI remains moderate and ultrasound-guided core biopsies or sentinel lymph node biopsies cannot be omitted.

Axillary lymph node biopsy in newly diagnosed invasive breast cancer: comparative accuracy of fine-needle aspiration biopsy versus core-needle biopsy.

PURPOSE: To compare the diagnostic accuracy of ultrasonographically (US)-guided fine-needle aspiration biopsy (FNAB) and core-needle biopsy (CNB) of the axillary lymph nodes (LNs) of patients with newly diagnosed invasive breast cancer. MATERIALS AND METHODS: This prospective single-center study had institutional review board approval, and written informed consent was obtained. Between April 2011 and March 2012, 178 consecutive patients (182 axillae) were evaluated by using axillary US. Sixty-six axillae fulfilled the inclusion criteria (cortical thickness greater than 2 mm or abnormal morphologic characteristics), and patients with these axillae underwent US-guided axillary LN biopsy. Both FNAB and CNB were obtained from the same suspicious LN. Patients with biopsy-proved metastasis underwent axillary clearance, and those with a negative biopsy underwent sentinel LN biopsy with completion axillary clearance if needed. Diagnostic performance was calculated separately for US, FNAB, and CNB. Statistical differences in sensitivities were evaluated by using the McNemar test. RESULTS: From the total study population, 45.6% (83 of 182 axillae) had metastases. A total of 66 axillae underwent both FNAB and CNB. The sensitivity for US was 61.4% (51 of 83 axillae), and specificity was 84.8% (84 of 88 axillae). The sensitivities for FNAB and CNB were 72.5% (37 of 51 axillae) and 88.2% (45 of 51 axillae), respectively (P = .008). Specificity for both was 100% (15 of 15 axillae). The negative predictive value for FNAB was 81.7%, and that for CNB was 91.2%. The positive predictive value was 100% for both methods. CONCLUSION: When accurate preoperative staging of the axilla is needed in patients with newly diagnosed invasive breast cancer, CNB is more sensitive than FNAB.