Objectives—A survey was conducted of acoustic output data received by the US Food and Drug Administration for diagnostic ultrasound devices whose indications for use include fetal applications to assess trends in maximum available acoustic output over time.
Methods—Data were collected from 124 regulatory submissions received between 1984 and 2010. Data collection excluded transducers not indicated for diagnostic fetal imaging. The output parameters of ultrasonic power, mean center frequency, and bone thermal index (TIB) were extracted or computed from the submissions for 3 periods: 1984–1989, 1992–1997, and 2005–2010. The data were stratified according to the following imaging modes: M-mode, B/M-mode, pulsed wave Doppler, color flow Doppler, and continuous wave Doppler.
Results—Ultrasonic power and maximum TIB values have increased roughly an order of magnitude from pre-1991 to post-1991 periods; the center frequency has decreased somewhat (4.2 to 3.4 MHz). The percentage of Doppler-mode transducers has increased substantially over time, with the majority of the diagnostic fetal imaging transducers currently designed to operate in Doppler modes; this increase is particularly important, since Doppler modes generate much higher TIB levels than B/M-modes. Color flow Doppler ultrasound currently operates at the highest mean ultrasonic power level (with a 14-fold increase over time).
Conclusions—The observed trends in increased acoustic output for both Doppler and non-Doppler modes underscore the widely recognized importance of adherence to the ALARA (as low as reasonably achievable) principle and prudent use in fetal ultrasound imaging.
Objectives—The purpose of this study was to evaluate neuropsychological test data in school-aged children whose fetal sonograms revealed mild isolated cerebral ventriculomegaly without asymmetry of the lateral ventricles.
Methods—Nine of 52 children 6 years and older with sonographic evidence of mild isolated cerebral ventriculomegaly without asymmetry of the lateral ventricles were able to be recruited for follow-up school-aged neuropsychological testing. The children received a half-day battery of neuropsychological tests, including the Wechsler Abbreviated Scales of Intelligence; Beery-Buktenica Developmental Test of Visual Motor Integration, Fifth Edition; Wide Range Achievement Test, Fourth Edition; and Integrated Visual and Auditory Continuous Performance Test. Parents completed the Conners 3 Parent Short Form and the Personality Inventory for Children, Second Edition.
Results—In this small group, other risk factors for neurodevelopmental disorders were often present, including preterm birth, perinatal hypoxia, and a family history of psychiatric disease or substance abuse. Within this sample, the proportion of children with a pattern of test results showing poorer nonverbal intelligence than verbal intelligence scores and poorer math than reading performance, as well as meeting criteria for a diagnosis of attention deficit/hyperactivity disorder, was higher than the basal rates of these problems among children in general.
Conclusions—Particularly given the complexity of various factors affecting neurodevelopment, follow-up neuropsychological evaluation is warranted in children with sonographic evidence of mild isolated cerebral ventriculomegaly without asymmetry of the lateral ventricle (eg, in the context of poor school performance).
Objectives—The purpose of this study was to develop new formulas for the expected fetal lung area-to-head circumference ratio in normal singleton pregnancies between 20 and 40 weeks’ gestation.
Methods—The lung-to-head ratio and complete fetal biometric parameters of 126 fetuses between 20 and 40 weeks’ gestation were prospectively measured. The lung-to-head ratio was measured by 3 different methods (longest diameter, anteroposterior diameter, and tracing). Formulas for predicting right and left lung-to-head ratios with regard to gestational age and biometric parameters were derived by stepwise regression analysis.
Results—New formulas for calculating right and left lung-to-head ratios by each measurement method were derived. The formulas included gestational age only and no biometric parameters.
Conclusions—The new formulas for estimating the expected lung-to-head ratio by the 3 different methods in normal singleton pregnancies up to 40 weeks’ gestation may help improve the prognostic power of observed-to-expected lung-to-head ratio assessment in fetuses with congenital diaphragmatic hernias.
Objective—To evaluate the causes of bidirectional flow in the vertebral artery detected by Doppler sonography and its differential diagnosis.
Methods—Twenty-nine patients with bidirectional flow in the vertebral artery were retrospectively studied. The vertebral artery parameters, including peak antegrade velocity (PAV), peak reversed velocity (PRV), maximum peak velocity (MPV), peak systolic velocity, resistive index (RI), and diameter, were measured. The MPV was defined as the MPV of bidirectional flow regardless of the velocity of antegrade or retrograde flow. To better predict the cause of bidirectional flow, receiver operating characteristic curves were constructed for these parameters, and the best cutoff values were obtained. The cause of bidirectional flow was determined by angiography.
Results—The causes of bidirectional flow were classified as the subclavian steal phenomenon (n = 21) and factors unrelated to the steal phenomenon (n = 8, including a hypoplastic vertebral artery [n = 4] and proximal vertebral artery stenosis and occlusion [n = 4]). Significant differences were observed between the steal phenomenon and non–steal phenomenon groups (P< .05) for MPV, PRV, PAV, target vertebral artery diameter, and contralateral RI. To determine the cause of bidirectional flow, areas under the receiver operating characteristic curves for the different parameters were obtained: 0.929 for MPV, 0.881 for PRV, 0.824 for PAV, 0.753 for target vertebral artery diameter, and 0.845 for contralateral RI. The cutoff value for MPV was 26.1 cm/s, and the accuracy was 93% (27 of 29).
Conclusions—Bidirectional flow in the vertebral artery is not always indicative of the subclavian steal phenomenon. Measurement of hemodynamic parameters in the vertebral artery, such as MPV, can facilitate determination of the cause of bidirectional flow.
Objectives—The purpose of this study was to investigate the changes in myocardial function in patients after coronary artery bypass graft (CABG) surgery using longitudinal and circumferential strain on speckle-tracking imaging.
Methods—A total of 145 patients who successfully underwent CABG surgery with a left ventricular ejection fraction (LVEF) of 50% or greater were enrolled in this study. Patients were classified into 4 groups based on age: group 1 (33–59 years), group 2 (60–64 years), group 3 (65–69 years), and group 4 (70–79 years). Routine echocardiography and longitudinal and circumferential strain measurements on speckle-tracking imaging were performed 1 week before and 1, 3, and 6 months after the CABG.
Results—In all groups, longitudinal strain increased significantly at 3 and 6 months after CABG therapy compared to baseline (P < .05). A significant increase in circumferential strain was found 1 month after the CABG in groups 1, 2, and 3, and a continuous increase in the parameter was observed in all groups 3 months after therapy (P < .05). However, the LVEF, left ventricular end-diastolic dimension, and stroke volume measured by routine echocardiography were not significantly changed after successful CABG treatment in all groups during 6 months of follow-up.
Conclusions—Based on the results of our study in all age groups, speckle-tracking imaging parameters are more effective than the LVEF, left ventricular end-diastolic dimension, and stroke volume for monitoring improvement in myocardial function after CABG surgery.
Objectives—Sonography for measuring intra-abdominal fat is more accurate than anthropometric measurements. Computed tomographic (CT) angiography has become an accurate noninvasive method for detection of coronary artery disease (CAD). We examined the associations between both sonographic and anthropometric measurements of abdominal adiposity and the presence of CAD on CT angiography.
Methods—We evaluated 83 consecutive patients (70% men; mean age ± SD, 56 ± 10.8 years) who were referred for CT angiography. Clinical and laboratory variables were determined, and CT angiography was performed using a 64-slice scanner. The severity of CAD was defined by visual assessment of any plaque, either calcified or noncalcified. Preperitoneal fat, subcutaneous fat, and visceral fat thicknesses were determined on sonography, and the abdominal fat index was calculated as the preperitoneal fat thickness-to-subcutaneous fat thickness ratio.
Results—Coronary artery disease was detected in 56 patients (67%). Patients with CAD had higher visceral fat thickness (9.3 ± 2.0 versus 8.2 ± 2.2 cm; P = .035) and a higher waist-to-hip ratio (0.97 ± 0.07 versus 0.92 ± 0.07; P = .018) than those without CAD. The preperitoneal fat thickness, subcutaneous fat thickness, and abdominal fat index were not correlated with the CAD status. After adjusting for traditional cardiovascular risk factors, however, only a waist-to-hip ratio higher than 0.95 remained significantly associated with the presence of CAD (odds ratio, 4.03; 95% confidence interval, 1.2–13.4).
Conclusions—This study shows that sonographically based obesity measurements are not superior to anthropometric indices in predicting the presence of CAD.
Objectives—The purpose of this study was to calculate a number of thyroid grayscale and Doppler sonographic parameters in healthy individuals and patients with Hashimoto thyroiditis or Graves disease and assess their sensitivity and specificity for the diagnosis of autoimmune thyroid disease using receiver operating characteristic curves.
Methods—A consecutive series of 153 patients (70 euthyroid and 54 hypothyroid patients with Hashimoto thyroiditis and 29 patients with Graves disease), all selected from an outpatient endocrine clinic, and 48 age- and sex-matched healthy control participants were evaluated with grayscale and power Doppler sonography.
Results—An irregular echo pattern in the thyroid parenchyma had 92.8% sensitivity for the diagnosis of autoimmune thyroid disease, and a left inferior thyroid artery peak systolic velocity (PSV) greater than 26.11 cm/s had 91.7% specificity. Of 8 patients with Hashimoto thyroiditis and normal grayscale sonographic characteristics, 6 had a left inferior thyroid artery PSV greater than 26.11 cm/s. A left inferior thyroid artery PSV greater than 61.65 cm/s had 82.8% sensitivity and 86.9% specificity for differentiating Hashimoto thyroiditis from Graves disease.
Conclusions—The left inferior thyroid artery PSV was the most accurate sonographic parameter for the diagnosis of autoimmune thyroid disease. Measurement of the inferior thyroid artery PSV could be used in patients with a normal grayscale sonographic appearance and inconclusive clinical and biochemical parameters to substantiate the diagnosis of autoimmune thyroid disease. Further studies are needed to evaluate and expand the use of this index.
Objectives—Patients with Hashimoto thyroiditis show structural changes of the thyroid that can be identified by a variety of sonographic criteria. We conducted this study to investigate whether there is a correlation between sonography and antibody activity and to assess the role of sonography in the diagnosis and follow-up of Hashimoto thyroiditis. In addition, we present a new classification system (termed the VESINC system [volume, echogenicity, sonographic texture, pseudonodular hypoechoic infiltration, nodules, and cysts]), which helps improve the clarity of sonographic findings.
Methods—The study included 223 consecutive patients with previously diagnosed Hashimoto autoimmune thyroiditis who attended the thyroid clinic of the German Armed Forces Central Hospital in Koblenz for follow-up examinations between 2006 and 2008. Laboratory tests were performed to measure the levels of free triiodothyronine, free thyroxine, thyrotropin, anti-thyroglobulin antibodies (TgAbs), and antithyroid peroxidase antibodies (TPOAbs). Sonography was performed according to a strict protocol. We then assessed whether a correlation existed between antibody activity and the 6 sonographic variables of the VESINC system.
Results—Hypoechogenicity, heterogeneity, and pseudonodular hypoechoic infiltration were associated with significantly higher TPOAb activity (P < .001). There were no significant correlations between the other sonographic variables examined (cysts, nodules, and volume) or the biometric data with the TPOAb and TgAb levels. In addition, an assessment of TgAb levels did not show significant differences in correlations with any of the sonographic variables.
Conclusions—Sonography is a noninvasive diagnostic imaging modality that provides information about the level of inflammatory activity. Markedly decreased echogenicity, heterogeneity, and multifocal pseudoinodular hypoechoic infiltration are indicative of a high level of inflammatory activity. The sonographic classification system presented here (VESINC system) can be a useful tool for comparing sonographic findings in a rapid and objective manner during follow-up of Hashimoto thyroiditis.
Objectives—First, we investigated the accuracy of carpal tunnel syndrome diagnosis by comparing the cross-sectional area of the median nerve measured at the level of proximal inlet of the carpal tunnel with that measured at the level of the distal radioulnar joint on sonography. Second, we evaluated the correlation between sonographic and neurophysiologic findings and clinical findings assessed by the Carpal Tunnel Syndrome Instrument of the Japanese Society for Surgery of the Hand (JSSH).
Methods—Fifty wrists in 34 patients and 81 wrists in 45 healthy volunteers were examined. The proximal cross-sectional area and the difference (Δ) between the proximal and distal cross-sectional areas were calculated for each wrist. Nerve conduction velocity tests were performed for all patients with carpal tunnel syndrome. The proximal, distal, and Δ cross-sectional areas were compared for the two groups. We examined the correlation between the proximal, distal, and Δ areas, nerve conduction velocity findings, and JSSH scores in the patients.
Results—The diagnosis of carpal tunnel syndrome determined by the Δ cross-sectional area was more accurate than the diagnosis determined by the proximal area on receiver operating characteristic curve analysis (P = .006). Statistically significant correlations were found between proximal area, Δ area, and nerve conduction velocity findings (proximal, r = 0.45; P = .0013; Δ, r = 0.44; P = .001). The proximal and distal areas were positively correlated with the JSSH symptom severity score (proximal, r= 0.39; P= .005; distal, r = 0.35; P = .014).
Conclusions—The cross-sectional area method using sonography has excellent performance for diagnosing carpal tunnel syndrome. It was useful for measuring the proximal and distal cross-sectional areas to evaluated the symptom severity and for calculating the Δ cross-sectional area to assess motor nerve damage in patients with carpal tunnel syndrome.
Objectives—Intensivist-performed focused sonography, including renal sonography, is becoming accepted practice. Whether internal medicine residents can be trained to accurately rule out renal obstruction and identify sonographic findings of chronic kidney disease is unknown. The purpose of this study was to test the ability of residents to evaluate for this specific constellation of findings.
Methods—Internal medicine residents were trained in a 5-hour module on focused renal sonography evaluating renal length, echogenicity, hydronephrosis, and cysts on a convenience sample of medical ward, intermediate care, and medical intensive care unit patients. All patients underwent comprehensive sonography within 24 hours. The primary outcome was represented by the Fleiss κ statistic, which indicated the degree of interobserver agreement between residents and radiologists. Sensitivity, specificity, and positive and negative predictive values were calculated using the comprehensive radiologist-read examination as the reference.
Results—Seventeen internal medicine residents imaged 125 kidneys on 66 patients. The average number of studies performed was 7.3 (SD, 6.6). Residents demonstrated excellent agreement with radiologists for hydronephrosis (κ = 0.73; P < .001; SE, 0.15; sensitivity, 94%; specificity, 93%), moderate agreement for echogenic kidneys (κ = 0.43; P < .001; SE, 0.13; sensitivity, 40%; specificity, 98%), and substantial agreement for renal cysts (κ = 0.61; P < .001; SE, 0.12; sensitivity, 60%; specificity, 96%). Residents showed sensitivity of 100% and specificity of 88% for identification of atrophic kidneys, defined as length less than 8 cm.
Conclusions—After a 5-hour training course, medical residents accurately identified hydronephrosis and key sonographic findings of chronic kidney disease in a cohort of medical patients. Screening for hydronephrosis and renal atrophy can be performed by medical residents after adequate training.
Objectives—The purpose of this study was to retrospectively evaluate the accuracy and safety of sonographically guided transhepatic biopsies of right upper renal and adrenal masses.
Methods—Ten sonographically guided transhepatic biopsies were performed in 10 patients with 6 right upper renal masses and 4 right adrenal masses that were invisible or inaccessible via an extrahepatic route. The control population comprised 19 sonographically guided extrahepatic biopsies that were performed in 19 patients with 18 right upper renal masses and 1 right adrenal mass. Transhepatic and extrahepatic biopsies were compared with respect to the diagnostic and complication rates. The mass sizes, biopsy distances, numbers and lengths of cores, and biopsy durations were also compared.
Results—The diagnostic rates of transhepatic and extrahepatic biopsies were 90% (9 of 10) and 89% (17 of 19), respectively (P > .999). The complication rates of transhepatic and extrahepatic biopsies were 10% (1 of 10) and 21% (4 of 19; P > .999). None of these biopsies resulted in major complications. The mean mass sizes, biopsy distances, and numbers of cores ± SD for transhepatic and extrahepatic biopsies were 33.0 ± 14.3 and 46.9 ± 18.5 mm, 100.5 ± 17.9 and 76.5 ± 9.9 mm, and 2.7 ± 0.9 and 4.0 ± 0.7, respectively (P = .046, .038, and .001). However, the core lengths and biopsy durations were not significantly different between these biopsies (P = .91 and .077).
Conclusions—Sonographically guided transhepatic core biopsies appear to be feasible and safe procedures for the histologic diagnosis of right upper renal and adrenal masses that are either invisible or inaccessible via an extrahepatic route.
Objectives—We hypothesized that sonographically guided core biopsy is an effective method for the differential diagnosis of adnexal masses and evaluated patients who underwent core biopsies in our gynecologic oncology department.
Methods—We reviewed the medical records of 55 patients who underwent sonographically guided core biopsies in our gynecologic oncology department between 2010 and 2013. Patients with suspected ovarian malignancies who were unsuitable for optimal debulking surgery and patients at risk for higher morbidity and mortality because of a poor performance status, suspected nongynecologic tumors, and peritoneal tuberculosis were indicated for sonographically guided biopsy.
Results—The indications for sonographically guided core biopsy were candidacy for suboptimal cytoreduction (n = 32 [58.2%]), a poor performance status (n = 11 [20.0%]), and suspected nongynecologic tumors (n = 12 [21.8%]). Histopathologic evaluations revealed primary ovarian tumors in 36 patients (65.5%). Tuberculosis was found to be the second most common disease (n = 8 [14.5%]) among the patients who underwent core biopsies. In 2 patients (3.6%), histologic examination revealed metastatic colorectal cancer.
Conclusions—Sonographically guided core biopsy may be preferred as a minimally invasive procedure for managing adnexal masses, particularly in patients with advanced ovarian cancer and high comorbidities who might benefit from neoadjuvant chemotherapy and in cases of suspected nongynecologic tumors, including pelvic tuberculosis.