Superficial Echogenic Lesions Detected on Neonatal Cranial Sonography
Possible Indicators of Severe Birth Injury
Objectives—The purpose of this study was to evaluate the characteristics and importance of superficial echogenic lesions around cranial sutures on neonatal cranial sonography.
Methods—We retrospectively reviewed the clinical records and neuroimaging studies of 40 neonates who had superficial echogenic lesions around sutures on neonatal cranial sonography. Magnetic resonance imaging (n = 18) and computed tomography (n = 2) were performed within 2 weeks after sonography. We correlated sonographic findings with computed tomographic and magnetic resonance imaging findings and analyzed them. We also evaluated the associated lesions, neurologic signs, and follow-up changes.
Results—Sonographically, the superficial echogenic lesions involved both sulci and perisulcal parenchyma in 39 neonates and were located in the frontal and parietal areas around the sagittal suture in 38 neonates. Magnetic resonance imaging revealed a pattern of hypoxic ischemic encephalopathy in 9 neonates, birth trauma in 3 neonates, a mixed pattern of hypoxic ischemic encephalopathy and trauma in 3 neonates, nonspecific single infarctions in 2 neonates, and lack of a defined lesion in 1 neonate. The associated lesions were subdural hemorrhage (n = 12), epidural hematoma (n = 4), germinal matrix hemorrhage (n = 3), intraventricular hemorrhage (n = 2), and periventricular leukomalacia (n = 1). All epidural hematomas were associated with scalp hematoma, and 2 patients had skull fractures. One neonate with epidural hematoma associated with a hypoxic ischemic encephalopathy pattern showed mild spasticity in both ankles until 16 months.
Conclusions—Superficial echogenic lesions detected around cranial sutures on neonatal sonography may be an indicator of more serious intracranial lesions such as more extensive hypoxic ischemic encephalopathy and intracranial hematomas, including epidural hematoma.
Evaluation of Underlying Lymphocytic Thyroiditis With Histogram Analysis Using Grayscale Ultrasound Images
Objectives—The purpose of this study was to evaluate diagnostic performance of histogram analysis using grayscale ultrasound (US) images in the diagnosis of lymphocytic thyroiditis.
Methods—Three radiologists reviewed a total of 505 US images and classified the images according to the presence/existence of lymphocytic thyroiditis. After 2 months, each reviewer repeated the process with the same 505 images in a randomly mixed order. The intraobserver and interobserver variability was analyzed with a generalized κ value. Four histogram parameters (mean value, standard deviation, skewness, and kurtosis) were obtained, and an index was calculated from principal component analysis. Diagnostic performances were compared.
Results—Of 505 patients, 125 (24.8%) had lymphocytic thyroiditis, and 380 (75.2%) had normal thyroid parenchyma on pathologic analysis. The κ value for intraobserver variance ranged from −0.002 to 0.781, and the overall κ values for interobserver variance were 0.570 and 0.214 in the first and second tests, respectively. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for the 3 reviewers versus the principal component analysis index were 28.0% to 83.2%, 43.7% to 82.6%, 53.5% to 79.0%, 24.6% to 56.2%, and 75.2% to 88.9% versus 58.4%, 72.4%, 68.9%, 41.0%, and 84.1%.
Conclusions—Histogram analysis of grayscale US images provided confirmable and quantitative information about lymphocytic thyroiditis and was comparable with performers’ assessments in diagnostic performance.
Noninvasive Evaluation of Benign and Malignant Superficial Lymph Nodes by Virtual Touch Tissue Quantification
A Pilot Study
Objectives—The purpose of this study was to investigate the value of Virtual Touch tissue quantification (Siemens Medical Solutions, Erlangen, Germany) for differentiation of benign and malignant superficial lymph node lesions.
Methods—Shear wave velocity (SWV) values were analyzed in 113 patients, who also had diagnoses by pathologic examination. The diagnostic performance of the SWV was evaluated by sensitivity and specificity at the optimum cutoff value and the area under the receiver operating characteristic curve (AUROC).
Results—A total of 60 benign lesions (32 reactive hyperplasia and 28 tuberculosis) and 53 malignant lesions (27 lymphomas and 26 metastatic carcinomas) were studied. The SWV was significantly different between benign (mean ± SD, 3.137 ± 0.857 m/s) and malignant (7.042 ± 1.427 m/s) lesions (P< .001) and yielded sensitivity of 92.5% (95% confidence interval [CI], 81.8%–97.9%) and specificity of 96.7% (95% CI, 88.5%–99.6%) at an optimum cutoff value of 4.645 m/s. The AUROC was 0.973 (95% CI, 0.924–0.994). To separate reactive hyperplasia from tuberculosis within benign lesions, a cutoff value of 2.978 m/s provided sensitivity of 92.9% (95% CI, 76.5%–99.1%) and a specificity of 100% (95% CI, 89.1%–100%), with an AUROC of 0.989 (95% CI, 0.920–1.000). To separate lymphoma from metastatic carcinoma within malignant lesions, a cutoff value of 7.302 m/s provided sensitivity of 88.5% (95% CI, 69.8%–97.6%) and specificity of 81.5% (95% CI, 61.9%–93.7%), with an AUROC of 0.906 (95% CI, 0.764–0.969).
Conclusions—Virtual Touch tissue quantification provides a promising noninvasive strategy for differentiation of benign and malignant superficial lymph node lesions.
Guidelines for Performing Dermatologic Ultrasound Examinations by the DERMUS Group
Objectives—To support standardization for performing dermatologic ultrasound examinations.
Methods—An international working group, called DERMUS (Dermatologic Ultrasound), was formed, composed of physicians who have been working on a regular basis and publishing in peer-reviewed articles on dermatologic ultrasound. A questionnaire on 5 critical issues about performance of the examinations was prepared and distributed by e-mail. The areas of discussion included technical aspects, main areas of application, minimum number of examinations per year required for assessing competence, qualifications of the personnel in charge of the examination, and organization of courses. Final recommendations were approved on the basis of the agreement of more than 50% of the members.
Results—The minimum frequency recommended for performing dermatologic examinations was 15 MHz. Routine use of color Doppler ultrasound and the performance of spectral curve analysis for assessing the main vascularity of lesions were suggested. Three-dimensional reconstructions were considered optional. The main dermatologic applications were benign tumors, skin cancer, vascular anomalies, cosmetic field, nail disorders, and inflammatory diseases. The minimum number of examinations per year suggested by the group for assessing competence was 300. A physician and not a sonographer was recommended to be the person in charge of performing the examination. On course organization, a minimum of 2 levels of complexity (basic and advanced) was suggested.
Conclusions—There is a need to standardize the performance and quality of dermatologic ultrasound examinations. The present guidelines written by an international group of specialists in the field may support this objective.
Evaluation of Parotid Glands With Real-time Ultrasound Elastography in Children
Objectives—The aim of this study was to determine the strain index for parotid glands in children by using ultrasound elastography.
Methods—In this prospective study, apparently healthy children were referred from the ear-nose-throat clinic to the radiology clinic for elastographic examinations. Conventional sonographic and elastographic examinations of the parotid glands were performed. A linear 5–12-MHz transducer was used to obtain the images.
Results—A total of 54 children were enrolled in this prospective study. The normal mean strain index value ± SD for the parotid glands was 1.24 ± 0.67 (range, 0.29–1.39) regardless of sex. The mean age of girls was 7.42 ± 2.94 years (range, 3–14 years), and the age of boys was 8.50 ± 3.46 years (range, 4–16 years). The strain index values for the parotid glands in boys was 1.25 ± 0.76, and in girls it was 1.22 ± 0.55. There was no statistically significant difference in the strain index values between girls and boys (P= .986). There was no correlation between the strain index and age (r = 0.026) or body mass index (r = 0.066).
Conclusions—This study determined the mean strain index values for apparently healthy children. Such information can serve as a baseline from which pathologic parotid diseases can be diagnosed with ultrasound elastography in combination with other sonographic criteria.
Abdominal pain is very common in the pediatric population (under18 years of age). Sonography is a safe modality that can often differentiate the frequently encountered causes of abdominal pain in children. This pictorial essay will discuss the sonographic findings of acute appendicitis, including the imaging appearance of a perforated appendicitis. It will also present the sonographic features of the relatively common mimics of appendicitis, such as mesenteric adenitis/gastroenteritis, intussusception, Meckel diverticulum, and ovarian torsion.