Hektor Grazhdani

Ultrasound elastography in the evaluation of thyroid pathology. Current status

Thyroid pathology including thyroid nodules and diffuse thyroid diseases represents often a diagnosing challenge for clinicians. US, although highly accurate in identifying thyroid nodules and diffuse thyroid diseases, is still not sufficiently accurate to evaluate them. US-elastography has been introduced in order to further increase US accuracy in many fields and eventually for thyroid disease. The aim of the present paper it to provide an update of the literature on different available techniques and the results reported both for thyroid nodules differentiation and for diffuse thyroid disease evaluation. Advantages and limitations of elastography are also discussed.

3D CT protocol in the assessment of the esophageal neoplastic lesions: can it improve TNM staging?

The purpose of this prospective observational study was the evaluation of the usefulness of MPR reconstructions and virtual endoscopy in the study of the esophageal carcinoma. Thirty-nine patients with esophageal cancer proved by means of endoscopy, underwent preoperative TNM staging with dynamic CT of the chest and abdomen with the aid of 3D rendering. Twenty-six patients underwent surgery, and the CT results were compared with histopathologic findings. In staging the T parameter, the CT with 3D reconstructions and virtual endoscopy, showed a sensitivity of 92% and an accuracy of 88%. In staging lymph nodes, the sensitivity in our study was 85%, the specificity 58%, and the accuracy 69%. Our protocol of the study of the esophageal cancer with 3D CT and virtual endoscopy, demonstrated a high concordance with the surgical and pathologic findings. The 3D reconstructed images were very helpful to the surgeons regarding preoperative planning. We performed an observational enquiry, and although this was a small study, it has, however, confirmed that the 3D imaging of the esophagus represents a valuable advantage to conventional imaging. Further studies with a larger number of patients are needed to prove its superiority to traditional CT imaging of the esophagus.

Growing indications for CEUS: The kidney, testis, lymph nodes, thyroid, prostate, and small bowel

Contrast enhanced ultrasonography (CEUS) is increasingly used for non-hepatic applications as well, so that nearly all organs have been investigated. Among them, there is a growing clinical use for a variety of pathologies of the kidney, testis, and small bowel. The possibility to differentiate benign from malignant nodes in cancer patients has been investigated. A new application is in the detection of sentinel nodes after intradermal microbubble injection. The need to distinguish thyroid nodules eligible for fine needle aspiration cytology has led to the use of CEUS in thyroid examinations as well. The potential of CEUS for prostate cancer detection has been extensively investigated, with encouraging initial results. Early promise, however, has not been fulfilled. New perspective regards evaluation of the extent of prostate tissue devascularization following ablative treatments.

Liver metastases: Contrast-enhanced ultrasound compared with computed tomography and magnetic resonance

The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound (US) for several applications, especially for the detection of metastases. In particular, contrast enhanced ultrasonography (CEUS) allows the display of the parenchymal microvasculature, enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases, which is similar to contrast-enhanced computed tomography (CT) and contrast-enhanced magnetic resonance imaging. Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US. Furthermore, studies have shown that CEUS yields sensitivities comparable to CT. In this review, we describe the state of the art of CEUS for detecting colorectal liver metastases, the imaging features, the literature reports of metastases in CEUS as well as its technique, its clinical role and its potential applications. Additionally, the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.

Strain US elastography for the characterization of thyroid nodules: Advantages and limitation

Thyroid nodules, with their high prevalence in the general population, represent a diagnostic challenge for clinicians. Ultrasound (US), although absolutely reliable in detecting thyroid nodules, is still not accurate enough to differentiate them into benign and malignant. A promising novel modality, US elastography, has been introduced in order to further increase US accuracy. The purpose of this review article is to assess the thyroid application of US strain elastography, also known as real-time elastography or quasistatic elastography. We provide a presentation of the technique, and of up-to-date literature, analyzing the most prominent results reported for thyroid nodules differentiation. The practical advantages and limitations of strain elastography are extensively discussed herein.

Diagnostic Accuracy and Interobserver Agreement of Quasistatic Ultrasound Elastography in the Diagnosis of Thyroid Nodules

PURPOSE To assess the best technique and the diagnostic accuracy of Quasistatic Ultrasound Elastography (QUE) in thyroid nodules. Interobserver agreement was also evaluated. MATERIALS AND METHODS A preliminary study of 50 patients with 54 thyroid nodules was performed with quantitative software in order to define the best cut-off value of different imaging methods. All patients underwent total thyroidectomy and histopathology findings served as the standard of reference. Thereafter, 154 nodules in 137 consecutive patients were prospectively evaluated by three operators. Findings at fine-needle aspiration cytology and histopathology (N = 60) served as the standard of reference. RESULTS The most accurate technique was the axial peri-intranodular measurement method which achieved an area under the ROC curve of 0.961 (95 %CI 0.848 - 1.00) and had an optimal cut-off value of 3.00. QUE in the differentiation of thyroid nodules showed for operator 1: sensitivity 90 % (95 %CI 73.5 - 97.9 %), specificity 92.7 % (95 %CI 86.7 - 96.6 %), LR+ 12.40 (6.54 - 23.50), LR- 0.11 (0.04 - 0.32) and accuracy 91.4 % (95 %CI 85.4 - 97.3 %); for operator 2: sensitivity 86.7 % (95 %CI 69.3 - 96.2 %), specificity 87.1 % (95 %CI 79.9 - 92.4 %), LR+ 6.72 (4.16 - 10.80), LR- 0.15 (0.06 - 0.38) and accuracy 86.9 % (95 %CI 80.0 - 93.7 %); for operator 3: sensitivity 80 % (95 %CI 61.4 - 92.3 %), specificity 83.9 % (95 %CI 76.2 - 89.9 %), LR+ 4.96 (3.20 - 7.70), LR- 0.24 (0.12 - 0.49) and accuracy 81.9 % (95 %CI 74.0 - 89.9 %). Interobserver agreement values between operator 1 and operator 2 (k = 0.79) (p < 0.05, 95 %CI 0.684 - 0.904), between operator 1 and operator 3 (k = 0.73, 95 %CI: 0.607 - 0.854) and between operator 2 and operator 3 (k = 0.71, 95 %CI: 0.584 - 0.835) were significant. CONCLUSION QUE provides accurate quantitative evaluation of thyroid nodules with low interobserver variability.

Elastography: A Practical Approach

The first two chapters cover basic fundamental principles of elastography, with subsequent chapters exploring pathology-specific utilization. The authors cover the extensively validated and implemented use of elastography for diffuse liver disease, and diseases of the breast andthyroid gland. They also discuss the potential benefits and limitations for the prostate, spleen, pancreas, kidneys, musculoskeletal system, salivary glands, lymph nodes, and testes. The book concludes with a chapter on potential future applications of this ever-evolving technology.