New Technologies in the Assessment of Carotid Stenosis: Beyond the Color-Doppler Ultrasound-High Frame Rate Vector-Flow and 3D Arterial Analysis Ultrasound.

Atherosclerotic plaque in the carotid artery is the main cause of ischemic stroke, with a high incidence rate among people over 65 years. A timely and precise diagnosis can help to prevent the ischemic event and decide patient management, such as follow up, medical, or surgical treatment. Presently, diagnostic imaging techniques available include color-Doppler ultrasound, as a first evaluation technique, computed tomography angiography, which, however, uses ionizing radiation, magnetic resonance angiography, still not in widespread use, and cerebral angiography, which is an invasively procedure reserved for therapeutically purposes. Contrast-enhanced ultrasound is carving out an important and emerging role which can significantly improve the diagnostic accuracy of an ultrasound. Modern ultrasound technologies, still not universally utilized, are opening new horizons in the arterial pathologies research field. In this paper, the technical development of various carotid artery stenosis diagnostic imaging modalities and their impact on clinical efficacy is thoroughly reviewed.

Qualitative Assessment of Contrast-Enhanced Ultrasound in Differentiating Clear Cell Renal Cell Carcinoma and Oncocytoma.

BACKGROUND: We aimed to assess whether clear cell renal cell carcinoma (ccRCC) can be differentiated from renal oncocytoma (RO) on a contrast-enhanced ultrasound (CEUS). METHODS: Between January 2021 and October 2022, we retrospectively queried and analyzed our prospectively maintained dataset. Renal mass features were scrutinized with conventional ultrasound imaging (CUS) and CEUS. All lesions were confirmed by histopathologic diagnoses after nephron-sparing surgery (NSS). A multivariable analysis was performed to identify the potential predictors of ccRCC. The area under the curve (AUC) was depicted in order to assess the diagnostic accuracy of the multivariable model. RESULTS: A total of 126 renal masses, including 103 (81.7%) ccRCC and 23 (18.3%) RO, matched our inclusion criteria. Among these two groups, we found significant differences in terms of enhancement (homogeneous vs. heterogeneous) (p < 0.001), wash-in (fast vs. synchronous/slow) (p = 0.004), wash-out (fast vs. synchronous/slow) (p = 0.001), and rim-like enhancement (p < 0.001). On the multivariate logistic regression, heterogeneous enhancement (OR: 19.37; p = <0.001) and rim-like enhancement (OR: 3.73; p = 0.049) were independent predictors of ccRCC. Finally, these two variables had an AUC of 82.5% and 75.3%, respectively. CONCLUSIONS: Diagnostic imaging for presurgical planning is crucial in the choice of either conservative or radical management. CEUS, with its unique features, revealed its usefulness in differentiating ccRCC from RO.

Multimodality ultrasound assessment of the spleen: Normal appearances and emergency abnormalities.

This paper summarizes the main splenic emergencies and their ultrasonographic findings to orient appropriate patient management. US requires minimal preparation time and allows to examine the parenchyma and to detect intraperitoneal fluid collections, which may be indirect evidence of solid organ injuries. In this paper, we analyze the role of B-mode, Doppler and Contrast-Enhanced Ultrasound in the diagnosis of splenic emergencies, with a particular focus on splenic infarction, infection, traumatic injuries and vascular splenic anomalies.

3D-Arterial analysis software and CEUS in the assessment of severity and vulnerability of carotid atherosclerotic plaque: a comparison with CTA and histopathology.

PURPOSE: Our purpose is to assess Multiparametric Ultrasound (MPUS) efficacy for evaluation of carotid plaque vulnerability and carotid stenosis degree in comparison with Computed Tomography angiography (CTA) and histology. MATERIAL AND METHODS: 3D-Arterial Analysis is a 3D ultrasound software that automatically provides the degree of carotid stenosis and a colorimetric map of carotid plaque vulnerability. We enrolled 106 patients who were candidates for carotid endarterectomy. Prior to undergoing surgery, all carotid artery plaques were evaluated with Color-Doppler-US (CDUS), Contrast-Enhanced Ultrasound (CEUS), and 3D Arterial analysis (3DAA) US along with Computerized Tomographic Angiography (CTA) to assess the carotid artery stenosis degree. Post-surgery, the carotid specimens were fixed with 10% neutral buffered formalin solution, embedded in paraffin and used for light microscopic examination to assess plaque vulnerability morphological features. RESULTS: The results of the CTA examinations revealed 91 patients with severe carotid stenoses with a resultant diagnostic accuracy of 82.3% for CDUS, 94.5% for CEUS, 98.4% for 3DAA, respectively. The histopathological examination showed 71 vulnerable plaques with diagnostic accuracy values of 85.8% for CDUS, 93.4% for CEUS, 90.3% for 3DAA, 92% for CTA, respectively. CONCLUSIONS: The combination of CEUS and 3D Arterial Analysis may provide a powerful new clinical tool to identify and stratify "at-risk" patients with atherosclerotic carotid artery disease, identifying vulnerable plaques. These applications may also help in the postoperative assessment of treatment options to manage cardiovascular risks.

Can strain US-elastography with strain ratio (SRE) improve the diagnostic accuracy in the assessment of breast lesions? Preliminary results.

PURPOSE: To assess the diagnostic value of strain ratio elastography (SRE), a semiquantitative elastosonographic method based on the displacement of the tissue from an external source (manual compression with the transducer), as compared and in combination with conventional ultrasound for the differentiation of breast lesions. METHODS: One hundred and eighty-two patients with breast lesions consecutively underwent B-mode, color Doppler US, and strain US-elastography. Each lesion was classified according to the BI-RADS lexicon by evaluating the size, the B-mode, and color Doppler features and then evaluated by SRE. Histology proven by biopsy was used as the gold standard and the patients with malignant lesions subsequently underwent operations. The diagnostic performance of each method was assessed with 2 × 2 contingency tables and ROC curve analysis. To maximize the SRE sensitivity and specificity, the SRE cut-off value was calculated using the Youden test. RESULTS: Histological examination revealed 66 benign and 116 malignant breast lesions. The conventional ultrasound showed sensitivity and specificity for the differentiation of benign and malignant lesions of 86.2% and 75.8%, respectively. Similar results were found for strain US-elastography with a cut-off of 2.49, with sensitivity and specificity of 89.7% and 72.7%, respectively. The association of conventional ultrasound with the SRE value increased the sensitivity (98.3%) but decreased the specificity compared with conventional US alone (63.6%). CONCLUSION: Strain US-elastography can be associated with BI-RADS US examination. According to our preliminary results, it helped increase the sensitivity although it decreased the specificity. However, further multicenter studies on a larger population are warranted.

Prospective evaluation of acoustic radiation force impulse technology in the differentiation of thyroid nodules: accuracy and interobserver variability assessment.

PURPOSE: The aim of this study is to assess the diagnostic efficacy and interobserver agreement of acoustic radiation force impulse (ARFI) elasticity imaging in differentiating thyroid nodules. METHODS: In our study, 74 consecutive patients (52 females, 22 males; age range 27-77 years, mean: 41 years) with 82 thyroid nodules (60 benign nodules, and 22 malignant) were examined by two radiologists with different experience. Patients underwent either cytology using fine needle aspiration cytology or thyroid surgery. The diagnostic performance of the two operators at ARFI with sensitivity, specificity, positive predictive and negative predictive value, and ROC curves was estimated. Inter-reader variability between the two operators was defined using Cohen's k. RESULTS: According to receiver operating characteristics ROC curves (AUROC = 0.86 for observer 1; 0.81 for observer 2) sensitivity, specificity, PPV and NPV of reader 1 and 2 were respectively: 90, 75, 90.91 and 96.55 %; (cut-off value of shear wave: 2.455 m/s); 90, 72, 90 and 96.90 % (cut-off value shear wave: 2.365 m/s). Concordance between the two operators was good (k = 0.755). CONCLUSIONS: This work is a feasibility study evaluating ARFI imaging. Its results suggest that ARFI imaging is a reproducible method which can be utilized with good diagnostic performance in the thyroid for discriminating benign and malignant nodules using the cut-off value of 2.455 m/s. However, larger studies are needed to validate this method.

Q-elastosonography of solid thyroid nodules: assessment of diagnostic efficacy and interobserver variability in a large patient cohort.

OBJECTIVE: Evaluation of the diagnostic efficacy and interobserver agreement of Q-elastography in the differentiation of benign from malignant thyroid nodules. METHODS: A total of 344 thyroid nodules in 288 patients were examined with grey-scale and colour Doppler ultrasound (CDUS) and Q-elastography by two independent operators. Nodules with hypoechogenicity, poorly defined margins, microcalcifications, and intralesional vascularity were classified as suspicious. Diagnostic performances of CDUS features and Q-elastography for predicting thyroid malignancy were estimated using ROC analysis. Cytology or histopathology was the reference standard. Interobserver agreement in the evaluation of CDUS and Q-elastography was assessed using Cohen's k-statistic. RESULTS: Q-elastography showed excellent diagnostic performance for the prediction of thyroid malignancy, with sensitivity of 93 % and specificity of 92 % for operator 1 (best cutoff at 2.02), and sensitivity of 84 % and specificity of 79 % for operator 2 (best cutoff at 1.86). Performance of Q-elastography was superior to that of CDUS. Reproducibility of the findings was excellent for both Q-elastography and CDUS features as assessed with Cohen's k, which was highest for strain ratio measurements (0.95) and lowest for the echogenicity score (0.83). CONCLUSIONS: Q-elastography showed excellent performance. It is a valid and reproducible diagnostic method as well as a promising tool for identifying suspicious solid thyroid nodules needing cytological assessment and surgery. KEY POINTS: • Elastography is an additional tool for optimal characterisation of malignant thyroid nodules. • The use of semiquantitative elastographic evaluation increases the diagnostic performance, • The interobserver agreement of quantitative elastography can be considered to be good.

MDCT assessment of ulcerative colitis: radiologic analysis with clinical, endoscopic, and pathologic correlation.

PURPOSE: Evaluate the utility of multidetector-row computed tomography (MDCT) in assessing the severity of ulcerative colitis (UC) in comparison with clinical assessment, colonoscopy, and histopathology. MATERIALS AND METHODS: Patients with UC evaluated with at least one abdominal contrast-enhanced CT study (CECT) within 7 days of colonoscopy with biopsy were included. CECT of 23 patients (12 male; mean age 40 years; age range, 20-72 years) were retrospectively evaluated in consensus by two radiologists. A total of 138 lower GI tract segments were evaluated by CECT and graded for the presence of bowel wall thickening, mucosal hyperenhancement, mural stratification, mesenteric hyperemia, pericolonic stranding, and lymph nodes. A cumulative CT severity score was calculated and correlated with clinical, colonoscopic, and histopathologic severity grades. RESULTS: The cumulative CT score and individual CECT scores for bowel wall thickening, mucosal hyperenhancement, and mural stratification showed positive correlation with clinical severity (P < 0.05). All individual CECT features as well as the cumulative CT score demonstrated statistically significant correlation with colonoscopic severity (P < 0.0001). Only wall thickening on CECT demonstrated significant correlation with histopathologic severity (P = 0.01). CONCLUSION: Disease severity assessment by MDCT demonstrates positive correlation with severity established by clinical assessment and colonoscopy. Only increasing wall thickness, as graded on MDCT, correlates with histopathologic disease severity.

Italian guidelines for noninvasive imaging assessment of focal liver lesions: development and conclusions.

OBJECTIVES: To develop guidelines for the noninvasive imaging assessment of focal liver lesions comparing different imaging modalities focused on (i) evaluating the imaging techniques in terms of (a) diagnostic accuracy; (b) role in the management of oncologic patients; (c) follow-up of benign lesions; and (ii) developing standard procedure for their use in patients with focal liver lesions that require targeted diagnostic characterization. METHODS: An explicit search strategy was used to conduct a systematic review of the literature in the English language from January 2000 to October 2007; the search covered PubMed, Embase, Pascal, SciSearch, and Cochrane Library databases. A panel of experts evaluated the selected studies and conveyed their view. RESULTS: The online search yielded 4960 titles and abstracts from which 176 studies were considered suitable for the final adherence-to-guidelines topic evaluation. An evidence grading system was not used as the guideline topic and the heterogeneity of the collected data did not fit with the currently used hierarchy of evidence. A panel of experts formulated several recommendations with grade and level which were expressed narratively and nonschematically. CONCLUSION: The recommendations reported in the study are based on an extensive literature evaluation and were developed by considering the appropriateness of the choice of the imaging techniques while noninvasively detecting and characterizing focal liver lesions.

Histologic assessment of biliary obstruction with different percutaneous endoluminal techniques.

BACKGROUND: Despite the sophisticated cross sectional image techniques currently available, a number of biliary stenosis or obstructions remain of an uncertain nature. In these pathological conditions, an "intrinsic" parietal alteration is the cause of biliary obstruction and it is very difficult to differentiate benign from malignant lesions using cross-sectional imaging procedures alone. We evaluated the efficacy of different endoluminal techniques to achieve a definitive pathological diagnosis in these situations. METHODS: Eighty patients underwent brushing, and or biopsy of the biliary tree through an existing transhepatic biliary drainage route. A subcoort of 12 patients needed balloon-dilatation of the bile duct and the material covering the balloon surface was also sent for pathological examination (balloon surface sampling). Pathological results were compared with surgical findings or with long-term clinical and instrumental follow-ups. Success rates, sensitivity, specificity, accuracy, confidential intervals, positive predictive value and negative predictive value of the three percutaneous techniques in differentiating benign from malignant disease were assessed.The agreement coefficient of biopsy and brushing with final diagnosis was calculated using the Cohen's "K" value. RESULTS: Fifty-six patients had malignant strictures confirmed by surgery, histology, and by clinical follow-ups. Success rates of brushing, balloon surface sampling, and biopsy were 90.7, 100, and 100%, respectively. The comparative efficacy of brushing, balloon-surface sampling, and biopsy resulted as follows: sensitivity of 47.8, 87.5, and 92.1%, respectively; specificity of 100% for all the techniques; accuracy of 69.2, 91.7 and 93.6%, Positive Predictive Value of 100% for all the procedures and Negative Predictive Value of 55, 80, and 75%, respectively. CONCLUSIONS: Percutaneous endoluminal biopsy is more accurate and sensitive than percutaneous bile duct brushing in the detection of malignant diseases (p < 0.01).

Contrast-enhanced US in the assessment of the ilio-caval axis in deep venous thrombosis.

PURPOSE: To assess the feasibility and the accuracy of a new technique in the evaluation of deep venous thrombosis (DVT) in the ilio-caval axis. MATERIALS AND METHODS: Thirty-eight patients with suspected DVT were prospectively examined with unenhanced and enhanced colour-Doppler ultrasonography, and ascending contrast venography. Thirty-five out of 38 patients underwent US phlebography, consisting in manual injection of Levovist (Schering Ag, Berlin, Germany) through a 21-G cannula in a suitable dorsal vein of the foot ipsilateral to the suspected DVT. Three patients in whom it was not possible to cannulate a dorsal vein of foot underwent contrast-enhanced US after injection of Levovist through an antecubital vein, but where excluded from the present study. A contrast venogram was nonetheless carried out in all out three patients for comparison with the US-phlebography findings. RESULTS: US-phlebography allowed better definition of the presence and extension of deep vein thrombosis in all patients, when compared to conventional color-Doppler US. In the evaluation of suspected acute thrombosis, the comparative efficacy of Doppler-US and US phlebography compared with ascending phlebography as the gold standard, was as follows: sensitivity of 85.7% and 90%, specificity of 71.4 and 100%, accuracy of 80.9 and 95.2%, PPV of 85.7, and 100%, and NPV of 71.4, and 75%, respectively. In the assessment of chronic thrombosis, US and US phlebography achieved a sensitivity of 90% and 100%, a specificity of 75% and 100%, an accuracy of 85.7% and 100%, a PPV of 100, 100%, a NPV of 87.5, 100%, respectively. No complications related to US phlebography were observed. CONCLUSIONS: US-phlebography is a promising tool in the assessment of deep vein thrombosis, being highly accurate and feasible. However, further studies based on larger series are mandatory to confirm our promising results and establish a standardised role for this new technique.