Hana Petrášová

Contrast-enhanced ultrasonography in the evaluation of incidental focal liver lesions: A cost-effectiveness analysis

AIM To determine whether contrast-enhanced ultrasonography (CEUS) as the first-line method is more cost-effective in evaluating incidentally discovered focal liver lesions (FLLs) than is computed tomography (CT) and magnetic resonance imaging (MRI). METHODS Between 2010 and 2015, our prospective study enrolled 459 patients with incidentally found FLLs. The biological nature of FLLs was assessed by CEUS in all patients. CT or MRI examinations were added in unclear cases. The sensitivity and specificity of CEUS were calculated. The total costs of CEUS examinations and of the added examinations performed in inconclusive cases were calculated. Afterwards, the theoretical expenses for evaluating incidentally discovered FLLs using CT or MRI as the first-line method were calculated. The results were compared. RESULTS The total cost of the diagnostic process using CEUS for all enrolled patients with FLLs was 75884 USD. When the expenses for additional CT and MRI examinations performed in inconclusive cases were added, the total cost was 90540 US dollar (USD). If all patients had been examined by CT or MR as the first-line method, the costs would have been 78897 USD or 384235 USD, respectively. The difference between the cost of CT and CEUS was 3013 USD (4%) and that between MRI and CEUS was 308352 USD (406.3%). We correctly described 97.06% of benign or malignant lesions, with 96.99% sensitivity and 97.09% specificity. Positive predictive value was 94.16% and negative predictive value was 98.52%. In cases with 4 and more lesions, malignancy is significantly more frequent and inconclusive findings significantly less frequent (P < 0.001). CONCLUSION While the costs of CEUS and CT in evaluating FLLs are comparable, CEUS examination is far more cost-effective in comparison to MRI.

Contrast-enhanced ultrasonography compared to gray-scale and power doppler in the diagnosis of peripheral lymphadenopathy.

OBJECTIVES The aim of the study was to evaluate the ability of contrast-enhanced ultrasonography compared to gray-scale B-mode and power Doppler in distinction between benign and malignant lymphadenopathy. METHODS In a prospective study ultrasonography was performed in 133 patients with superficial lymphadenopathy (73 men, 60 women; mean age of 51 years, range: 18-86 years), who were examined for palpable mass in the neck, axilla or groin (104/133) and for clinical suspicion of lymphoma on the basis of positive PET/CT (29/133). 133 nodes were examined, subsequently preoperatively localized under ultrasound guidance and surgically removed; longitudinal to transverse ratio, location of nodal vessels by power Doppler and pattern of enhancement by contrast-enhanced ultrasonography with 1.5ml intravenous bolus of sulphur hexafluoride contrast agent were documented. The ultrasound findings were compared with the histology. RESULTS Of all the nodes extirpated, 33 were benign, 100 were malignant (40 metastases, 60 lymphomas). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of conventional techniques were 72%, 63.6%, 85.7%, 42.9%, 67.8% for longitudinal to transverse ratio; 73%, 60.6%, 84.9%, 42.6%, 68.3% for power Doppler versus 98.0%, 54.5%, 86.7%, 90.0%, 76.3% for contrast-enhanced ultrasonography according to Receiver Operating Characteristic analysis. CONCLUSIONS Receiver Operating Characteristic analysis confirmed higher degree of diagnostic accuracy of contrast-enhanced ultrasonography in comparison with conventional techniques. Evaluation of nodal perfusion after intravenous administration of microbubble contrast agent can be helpful in differentiation of benign from malignant nodes.