Kazimierz T. Szopinski

Tissue Harmonic Imaging Utility in Breast Sonography

Objective. To determine the impact of tissue harmonic imaging on visualization of focal breast lesions and to compare gray scale contrast between focal breast lesions and fatty tissue of the breast between tissue harmonic imaging and fundamental frequency sonography. Methods. A prospective study was performed on 219 female patients (254 lesions) undergoing sonographically guided fine‐needle biopsy. The fundamental frequency and tissue harmonic images of all lesions were obtained on a scanner with a wideband 7.5‐MHz linear probe. Twenty‐three breast carcinomas, 6 suspect lesions, 9 fibroadenomas, 1 papilloma, 1 phyllodes tumor, 162 unspecified solid benign lesions, and 40 cysts were found. In 12 cases the fine‐needle aspiration did not yield sufficient material. The gray scale intensity of the lesions and adjacent fatty tissue was measured with graphics software, and the gray scale contrast between lesions and adjacent fatty tissue was calculated. Results. Tissue harmonic imaging improved the gray scale contrast between the fatty tissue and breast lesions in 230 lesions (90.6%; P < .001) compared with fundamental frequency images. The contrast improvement was bigger in breasts with predominantly fatty or mixed (fatty/glandular) composition than in predominantly glandular breasts. The overall conspicuity, lesion border definition, lesion content definition, and acoustic shadow conspicuity were improved or equal in the harmonic mode for all lesions. Conclusions. The tissue harmonic imaging technique used as an adjunct to conventional breast sonography may improve lesion detectability and characterization.

Shear Wave Elastography May Add a New Dimension to Ultrasound Evaluation of Thyroid Nodules: Case Series with Comparative Evaluation

Although elastography can enhance the differential diagnosis of thyroid nodules, its diagnostic performance is not ideal at present. Further improvements in the technique and creation of robust diagnostic criteria are necessary. The purpose of this study was to compare the usefulness of strain elastography and a new generation of elasticity imaging called supersonic shear wave elastography (SSWE) in differential evaluation of thyroid nodules. Six thyroid nodules in 4 patients were studied. SSWE yielded 1 true-positive and 5 true-negative results. Strain elastography yielded 5 false-positive results and 1 false-negative result. A novel finding appreciated with SSWE, were punctate foci of increased stiffness corresponding to microcalcifications in 4 nodules, some not visible on B-mode ultrasound, as opposed to soft, colloid-inspissated areas visible on B-mode ultrasound in 2 nodules. This preliminary paper indicates that SSWE may outperform strain elastography in differentiation of thyroid nodules with regard to their stiffness. SSWE showed the possibility of differentiation of high echogenic foci into microcalcifications and inspissated colloid, adding a new dimension to thyroid elastography. Further multicenter large-scale studies of thyroid nodules evaluating different elastographic methods are warranted.

Advantages and disadvantages of 3D ultrasound of thyroid nodules including thin slice volume rendering

BackgroundThe purpose of this study was to assess the advantages and disadvantages of 3D gray-scale and power Doppler ultrasound, including thin slice volume rendering (TSVR), applied for evaluation of thyroid nodules.MethodsThe retrospective evaluation by two observers of volumes of 71 thyroid nodules (55 benign, 16 cancers) was performed using a new TSVR technique. Dedicated 4D ultrasound scanner with an automatic 6-12 MHz 4D probe was used. Statistical analysis was performed with Stata v. 8.2.ResultsMultiple logistic regression analysis demonstrated that independent risk factors of thyroid cancers identified by 3D ultrasound include: (a) ill-defined borders of the nodule on MPR presentation, (b) a lobulated shape of the nodule in the c-plane and (c) a density of central vessels in the nodule within the minimal or maximal ranges. Combination of features provided sensitivity 100% and specificity 60-69% for thyroid cancer.Calcification/microcalcification-like echogenic foci on 3D ultrasound proved not to be a risk factor of thyroid cancer.Storage of the 3D data of the whole nodules enabled subsequent evaluation of new parameters and with new rendering algorithms.ConclusionsOur results indicate that 3D ultrasound is a practical and reproducible method for the evaluation of thyroid nodules. 3D ultrasound stores volumes comprising the whole lesion or organ. Future detailed evaluations of the data are possible, looking for features that were not fully appreciated at the time of collection or applying new algorithms for volume rendering in order to gain important information. Three-dimensional ultrasound data could be included in thyroid cancer databases. Further multicenter large scale studies are warranted.

Tissue harmonic imaging of thyroid nodules: Initial experience

Objective. To determine the impact of tissue harmonic imaging on visualization of the thyroid and gray scale contrast between thyroid nodules and adjacent thyroid parenchyma. Methods. A prospective study was performed on 144 patients (148 lesions) undergoing sonographically guided fineneedle biopsy. The fundamental frequency and tissue harmonic images were obtained on a scanner with a wideband 7.5‐MHz linear probe. One hundred forty‐two benign nodules, 2 papillary carcinomas, 1 anaplastic carcinoma, and 1 metastatic lesion were found. In 1 case a suggestion of a follicular carcinoma was raised, and in 1 case no diagnostic material was obtained. The gray scale intensity of the lesions and adjacent thyroid tissue was measured with graphics software, and the gray scale contrast between lesions and adjacent thyroid tissue was calculated. Additionally, the overall conspicuity and border definition were evaluated by 2 independent observers. Results. Tissue harmonic imaging improved the gray scale contrast between thyroid nodules and adjacent thyroid parenchyma in 116 lesions (78.4%). The overall conspicuity and border definition were improved or equal in the harmonic mode for most lesions. Conclusions. The tissue harmonic imaging technique used as an adjunct to conventional thyroid sonography may improve lesion detectability and characterization.