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Purpose: To assess the value of real-time sonographic (US) elastography in the diagnosis of subacute thyroiditis (SAT). Methods: This study included 29 lesions from 20 patients with SAT, 33 nodules from 24 patients with multinodular goiter, and 27 nodules from 23 patients with thyroid cancer. Eighty-nine lesions in these patients were examined by grayscale US and real-time US elastography. An elasticity score (ES), based on four classes of tissue stiffness (class 1 for soft lesions; class 2 and 3 for lesions intermediate in stiffness; class 4 for inelastic lesions), was introduced. The distribution of ESs for SAT and multinodular goiter or thyroid cancer was compared. Also, the correlation between serum-free thyroxine (FT4) concentrations and ESs for lesions in patients with SAT was analyzed. Results: Nineteen of 29 SAT lesions had an ES of 3; the rest had an ES of 4. Of 33 multinodular goiter nodules, 5 had an ES of 1, 23 had an ES of 2, and 5 had an ES of 3. Eleven of 27 malignant thyroid nodules had an ES of 3; 15 had an ES of 4, and 1 had an ES of 2. In the distribution of ESs, there was a statistically significant difference between SAT lesions and multinodular goiter nodules (p 0.05). No correlation existed between serum FT4 concentrations and ESs for the lesions in patients with SAT (p > 0.05). Conclusions: Real-time US elastography does not provide conclusive information in the diagnosis and differential diagnosis of SAT due to its inability to distinguish between SAT and thyroid cancer. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011

A new method to measure placental volume in mid-pregnancy using realtime ultrasound is described. The method is an adaptation of the B-mode parallel planimetric technique. The mean error of in vitro measurements on 45 balloons (mean volume 186 mL range: 88–485 mL) was −2.24 mL, standard deviation 6.76 mL. The error standard deviation of in vivo placental volume measurements was 16.4 mL (volume range: 173–396.5 mL). Placental measurements were made on 175 women between 14.3 weeks and 21.4 weeks, menstrual age (MA) and a smooth centile curve derived. Median volume increased linearly from 144 to 329 mL. The size of the ultrasound probe limits the technique to use before 20 weeks, MA. © 1994 John Wiley & Sons, Inc.

The retroplacental clear area is a hypoechoic region at the placental-endometrial interface which is frequently demonstrated with high-resolution equipment. During pulsed Doppler examination of the retroplacental clear area, venous signals were obtained in 26 of 27 cases. This is strong evidence that this region is composed of dilated veins.

In an effort to evaluate the efficacy of measuring abdominal circumference with real-time ultrasound, 53 patients were scanned with both contact scanning and linear array real time. Image measurements were made blindly from both types of equipment. Abdominal circumference measurements with real time compared favorably with those obtained from contact images (r = +0.984).

The physical principles and clinical applications of a high-resolution, dynamically focused phased-array real time ultrasound system are described. Advantages of the real time technique include rapid survey capability, efficient selection of an appropriate tomographic plane, identification of pulsating structures, and dynamic studies. The capabilities of a high resolution phased array with extended dynamic focusing to a range of 15-20 cm are demonstrated in vascular, abdominal, and obstetric imaging. Appropriate clinical examples showing normal and pathological anatomy are presented. Comparisons with conventional B scans are illustrated.

The adrenals were studied prospectively with real-time ultrasound in a series of 60 healthy individuals and 13 patients with small adrenal masses sized 8-20 mm in diameter. In only one of the 60 healthy subjects was a normal adrenal gland delineated as a distinct hypoechoic structure. In all other instances only the highly echogenic suprarenal fat could be displayed. Visualization of small tumors was successful in 12 of 13 patients. The suprarenal area and small lesions were best demonstrated by a lateral intercostal approach using longitudinal and transverse scanning planes. The best access was through the 9th/10th intercostal space at the junction with the anterior and middle axillary lines on the right and the posterior axillary line on the left. Indexing Words: Adrenal gland · Ultrasound.

Using a linear array real-time scanner and a video disc with slow-motion review capability, the pancreatic duct was seen in 86% of normal subjects. It appeared as a tubular structure in 65% of patients and as a single line echo in 21%. The normal pancreatic duct measures 2 mm in diameter or less.

Tongue movement during production of the speech sounds /a/, /i/, and /k/ was examined with a real-time sector scanner positioned submentally. With this technique, it is possible to obtain excellent visualization of the tongue surface and to identify much of the intrinsic soft tissue anatomy of the tongue and floor of the mouth. Tongue movement and configuration were found to be consistent for 10 normal speakers, especially for /i/ and /k/. Three patients with neurological disease and dysarthria showed varying but significant differences in articulation compared to normals. It appears that real-time ultrasound imaging of the oral cavity is a potentially valuable technique for the clinical investigation of normal and abnormal speech.

Improvements in ultrasound technology have now made possible detailed visualization of fetal intracranial anatomy. Structures such as the midbrain, thalami, and lateral ventricles can be routinely imaged. Measurements of the ratio between lateral ventricular width and cerebral hemispheric width demonstrate a steady decrease from a mean of 56% at 15 wk gestation to 28% at term reflecting the relatively more rapid growth of the cerebral hemispheres as compared with the cerebral ventricles. Application of this new ultrasound data greatly facilitates accurate and consistent biparietal diameter estimations and early diagnosis of fetal hydrocephalus and other fetal cranial anomalies. This article describes the axial fetal cranial anatomy as demonstrated sonically and includes a table for normal fetal ventricular size at various gestational ages, based on evaluation of 196 normal fetuses. Some of the more common fetal cranial anomalies amenable to ultrasound diagnosis in utero are discussed.

The high-resolution graphics facility of a microcomputer has been synchronized with real-time ultrasound images on a television monitor, allowing quick and accurate measurements of linear distances, arc lengths, perimeter lengths, and areas, whether regular or irregular in shape. No particular knowledge of computers is required, as the program gives step-by-step directions. However, the full facilities of a 48K microcomputer using BASIC language remain accessible, which is a considerable advantage over equivalent measuring systems currently available.

The frequent occurrence of low-level artifactual echoes in normally echo-free areas of real-time images is shown to be due to a range-ambiguity effect caused by the fast frame rate of real-time equipment. The experimental data demonstrates the range-ambiguous echoes to be present in linear array and mechanical sector scanner real-time images. Several suggestions are made to reduce the effect of the artifact in real-time images. A set of real-time acceptance tests that utilize this artifact are proposed.