Showing papers in "Journal of Ultrasound in Medicine in 2005"

Ultrasonographic differentiation between metastatic and benign lymph nodes in patients with papillary thyroid carcinoma.

Abstract: Objective. The purpose of this study was to evaluate the ultrasonographic characteristics of metastatic lymph nodes in patients with papillary thyroid carcinoma. Methods. The ultrasonographic characteristics of lymph nodes were analyzed in 112 consecutive patients who underwent thyroidectomy and lymph node dissection, with the diagnosis being confirmed by anatomopathologic examination. Results. A total of 198 lymph nodes were metastatic, and 152 were benign (normal or with nonspecific lymphadenitis). Minimum axial diameters of 7 mm for level II (upper internal jugular chain) and 6 mm for the rest of the neck were observed in 93% of metastatic lymph nodes, absence of an echogenic hilum in 88%, hyperechogenicity in relation to the adjacent muscles in 86%, a round shape in 80%, calcifications in 49.5%, and intranodal cystic necrosis in 20%. These ultrasonographic characteristics were observed in 17%, 10%, 4.5%, 29.5%, 0%, and 0% of benign lymph nodes, respectively. Conclusions. Even basic ultrasonographic characteristics (shape, echogenicity and echogenic hilum, calcifications, and intranodal cystic necrosis) help in the differentiation between metastatic and

Rudimentary horn pregnancy: first-trimester prerupture sonographic diagnosis and confirmation by magnetic resonance imaging.

Abstract: Objective. Two cases of rudimentary horn pregnancy diagnosed in the first trimester by sonography and confirmed by magnetic resonance imaging (MRI) are reported. We suggest criteria for early, prerupture sonographic diagnosis of this rare condition. Methods. We report a case in which pregnancy in a rudimentary horn was suspected on routine sonographic examination. In the second case, sonographic examination at 11 weeks’ gestation revealed a right unicornuate uterus and a noncommunicating left rudimentary horn containing a gestational sac. In both cases, MRI clearly confirmed the sonographic diagnosis, showing an empty cavity of the uterine body and a pregnant uterine horn without an endometrial communication to the uterine body. Results. Both patients underwent surgery, and the pregnant rudimentary horns were resected with no complications. Conclusions. We suggest the following criteria for sonographic diagnosis of rudimentary horn pregnancy: (1) a pseudopattern of a asymmetrical bicornuate uterus, (2) absent visual continuity tissue surrounding the gestational sac and the uterine cervix, and (3) the presence of myometrial tissue surrounding the gestational sac. Typical hypervascularization of placenta accreta may support the diagnosis. Additionally, MRI can be used to confirm the diagnosis before an invasive procedure is undertaken.

Clinical utility of sonography in diagnosing plantar fasciitis.

Abstract: OBJECTIVE The purpose of this study was to investigate the efficacy of sonography in the detection of plantar fasciitis (PF) compared with magnetic resonance imaging (MRI) findings in subjects with inferior heel pain. METHODS Seventy-seven patients with unilateral (n = 9) and bilateral (n = 68) heel pain were studied. Seventy-seven age- and sex-matched asymptomatic subjects served as a control group. Magnetic resonance imaging was used to establish a diagnosis of PF with sagittal T1-weighted, T2-weighted, and short tau inversion recovery sequences. The sonographic appearances of PF were compared with MRI findings. Plantar fascia and heel pad thickness were also measured on both imaging modalities. RESULTS Compared with MRI, sonography showed 80% sensitivity and 88.5% specificity in assessing PF. A strong correlation was found between plantar fascia and fat pad thickness measurements done by sonography (P < .001; r = 0.854) and MRI (P < .001; r = 0.798). Compared with the asymptomatic volunteers, patients with PF had significant increases in plantar fascia and heel pad thicknesses, weight, and body mass index (P = .0001). Heel pad thickness was also significantly increased with pain duration (P = .021). CONCLUSIONS Although MRI is the modality of choice in the morphologic assessment of different plantar fascia lesions, sonography can also serve as an effective tool and may substitute MRI in the diagnosis of PF.

Contrast-enhanced ultrasonography in the diagnosis of solid renal tumors.

Abstract: Objective The purpose of this study was to evaluate the usefulness of contrast-enhanced ultrasonography (CEUS) in the diagnosis of solid renal tumors. Methods Twenty-nine patients with solid tumors detected on gray scale ultrasonography underwent resection for suspected renal malignancy. Findings of arterial phase contrast computed tomography (CT) and CEUS were compared for each diagnosis. Results Histopathologic examination of resected lesions showed malignancy in 26 patients (clear cell carcinoma, n = 18; papillary renal cell carcinoma, n = 6; collecting duct carcinoma, n = 1; and infiltrative urothelial carcinoma, n = 1) and benign tumors in 3 patients (oncocytoma, n = 2; and angiomyolipoma, n = 1). Contrast CT failed to show tumor blood flow in 5 of 29 patients, whereas CEUS showed this in all patients. Positive predictive values of CEUS and contrast CT in the diagnosis of renal malignancy were 100% and 82.8%, respectively. Among clear cell carcinomas, hypervascularity was observed on contrast CT in 16 of 18 patients and on CEUS in 17 of 18 patients. On the basis of hypervascularity, diagnostic sensitivity values for clear cell carcinoma were 94.4% for CEUS and 88.9% for contrast CT, whereas specificity values were 45.5% for CEUS and 72.7% for contrast CT. Among papillary cell carcinomas, contrast CT showed avascular lesions in 4 of 6 patients. However, CEUS showed blood flow in these lesions, leading to diagnosis of hypovascular renal tumors. Conclusions Contrast-enhanced ultrasonography was more sensitive for detecting slight tumor blood flow than contrast CT and was useful in preoperatively diagnosing malignant hypovascular renal tumors but was less so for hypervascular renal tumors.

Interlaboratory comparison of ultrasonic backscatter coefficient measurements from 2 to 9 MHz.

Abstract: Objective As are the attenuation coefficient and sound speed, the backscatter coefficient is a fundamental ultrasonic property that has been used to characterize many tissues. Unfortunately, there is currently far less standardization for the ultrasonic backscatter measurement than for the other two, as evidenced by a previous American Institute of Ultrasound in Medicine (AIUM)-sponsored interlaboratory comparison of ultrasonic backscatter, attenuation, and speed measurements (J Ultrasound Med 1999; 18:615-631). To explore reasons for these disparities, the AIUM Endowment for Education and Research recently supported this second interlaboratory comparison, which extends the upper limit of the frequency range from 7 to 9 MHz. Methods Eleven laboratories were provided with standard test objects designed and manufactured at the University of Wisconsin (Madison, WI). Each laboratory was asked to perform ultrasonic measurements of sound speed, attenuation coefficients, and backscatter coefficients. Each laboratory was blinded to the values of the ultrasonic properties of the test objects at the time the measurements were performed. Results Eight of the 11 laboratories submitted results. The range of variation of absolute magnitude of backscatter coefficient measurements was about 2 orders of magnitude. If the results of 1 outlier laboratory are excluded, then the range is reduced to about 1 order of magnitude. Agreement regarding frequency dependence of backscatter was better than reported in the previous interlaboratory comparison. For example, when scatterers were small compared with the ultrasonic wavelength, experimental frequency-dependent backscatter coefficient data obtained by the participating laboratories were usually consistent with the expected Rayleigh scattering behavior (proportional to frequency to the fourth power). Conclusions Greater standardization of backscatter measurement methods is needed. Measurements of frequency dependence of backscatter are more consistent than measurements of absolute magnitude.

Suboptimal second-trimester ultrasonographic visualization of the fetal heart in obese women: should we repeat the examination?

Abstract: Objective. The purpose of this study was to determine whether a repeated antenatal ultrasound examination improves fetal cardiac visualization for the obese and nonobese population. Methods. A computerized ultrasound database (October 1999-June 2003) was used to identify singleton pregnancies undergoing repeated prenatal ultrasound examinations because of initial suboptimal ultrasonographic visualization (SUV) of the 4-chamber view, outflow tracts, or both. Women with maternal diabetes, abnormal maternal serum screening results, or known fetal anomalies at the initial examination were excluded. Patients were classified by maternal body mass index (BMI): less than 30 kg/mg 2 (nonobese), 30 to 34.9 kg/mg 2 (class I obesity), 35 to 39.9 kg/mg 2 (class II obesity), and 40 kg/mg 2 or greater (morbid obesity). The association between maternal BMI and SUV of the fetal heart was analyzed. Results. Three hundred seventy-two patients were abstracted from the database. The median gestational age was 19.0 weeks at the initial visit (range, 18.0-21.9 weeks) and 21.4 weeks at the second visit (range, 18.9-23.9 weeks). The median BMI was 32.6 kg/m 2 (range, 164-58.7 kg/m 2 ). Sixty-three percent of patients were obese (BMI ≥30). Cardiac anatomy continued to have SUV in 11 % of the women. The rate of SUV was associated with the obesity class (1.5% for nonobese, 12% for obesity I, 17% for obesity II, and 20% for morbid obesity; P <.0001). A cardiac anomaly was found in 1 of 372 repeated examinations (arteriovenous canal defect) for a patient with BMI of 24.8 kg/m 2 . Conclusions. Repeated ultrasound examination for SUV of the fetal heart at a later gestational age dramatically reduces SUV. However, obese patients continue to have much higher rates of persistent SUV.

Three- and 4-dimensional ultrasound in obstetrics and gynecology: proceedings of the American Institute of Ultrasound in Medicine Consensus Conference.

Abstract: The American Institute of Ultrasound in Medicine convened a panel of physicians and scientists with interest and expertise in 3-dimensional (3D) ultrasound in obstetrics and gynecology to discuss the current diagnostic benefits and technical limitations in obstetrics and gynecology and consider the utility and role of this type of imaging in clinical practice now and in the future. This conference was held in Orlando, Florida, June 16 and 17, 2005. Discussions considered state-of-the-art applications of 3D ultrasound, specific clinical situations in which it has been found to be helpful, the role of 3D volume acquisition for improving diagnostic efficiency and patient throughput, and recommendations for future investigations related to the utility of volume sonography in obstetrics and gynecology.

Imaging of focal liver lesions: low-mechanical-index real-time ultrasonography with SonoVue.

Abstract: Objective. The purpose of this study was to evaluate the usefulness of a contrast-enhanced contrastspecific ultrasonographic technique with a low mechanical index for characterization of focal liver lesions. Methods. Contrast-specific ultrasonography was used to assess 144 patients with 147 focal liver lesions: 87 primary liver carcinomas, 27 hemangiomas, 16 focal nodular hyperplasias, 5 hepatic abscesses, 3 inflammatory pseudotumors of the liver, and 9 metastases. A sulfur hexafluoride gas‐based contrast agent was used with a mechanical index of 0.08 to 0.11. Results. On contrastenhanced ultrasonography, the typical hemodynamic pattern of primary liver carcinoma was the whole-lesion enhancement or mosaic enhancement in the arterial phase with an enhancement defect in the late phase (sensitivity, 92.0%; specificity, 86.7%). The most common enhancement pattern of hemangioma was that enhancement appeared in the periphery first and progressively filled into the lesion center (sensitivity, 96.3%; specificity, 97.5%). The enhancement pattern of focal nodular hyperplasia was that the whole lesion enhanced early and rapidly in the arterial phase with a centrifugal radiating configuration and appeared isoechoic or hyperechoic until the late phase (sensitivity, 87.6%; specificity, 94.5%). The central scar was detected in 31.3% of cases in the late phase. The specific enhancement of a hepatic abscess was the honeycomblike enhancement in all phases (sensitivity, 80.0%; specificity, 100%). No enhancement of a lesion in all phases was specific for an inflammatory pseudotumor of the liver. Conclusions. Contrast-enhanced real-time ultrasonography is a promising approach in the noninvasive characterization of focal liver lesions and can be useful as a first-line

Cerebroplacental Doppler ratio and adverse perinatal outcomes in intrauterine growth restriction: evaluating the impact of using gestational age-specific reference values.

Abstract: Objective The purpose of this study was to compare the impact of using gestational age-specific reference levels of the cerebroplacental Doppler ratio (CPR) with categorical threshold in the prediction of adverse perinatal outcomes in growth-restricted pregnancies. Methods A retrospective cohort study of cases of intrauterine growth restriction over a 3-year period was conducted. The umbilical artery and middle cerebral artery pulsatility indices were converted to CPRs. The efficacy of using gestational age-specific reference levels of CPRs in predicting adverse outcomes was compared with the use of a CPR of less than 1.08. Adverse perinatal outcomes evaluated included cesarean delivery for nonreassuring fetal heart tones, umbilical artery pH less than 7.0, 5-minute Apgar scores less than 7.0, intraventricular hemorrhage greater than grade 2, periventricular leukomalacia, respiratory distress syndrome, and perinatal death. Results Of 183 pregnancies meeting our inclusion criteria, there were 70 with at least 1 adverse outcome. With the use of a CPR ratio below the 5th percentile for gestational age, the sensitivity, specificity, and positive and negative predictive values for predicting an adverse outcome were 65%, 73%, 73%, and 65%, respectively, with an odds ratio (95% confidence interval) of 5.2 (1.4-19.4; area under the receiver operating characteristic curve, 0.69). With a CPR threshold of less than 1.08, the sensitivity, specificity, and positive and negative predictive values were 72%, 62%, 68%, and 67%, with an odds ratio (95% confidence interval) of 4.2 (1.2-15.3; area under the receiver operating characteristic curve, 0.67). Conclusions An abnormal CPR is associated with adverse perinatal outcomes in growth-restricted fetuses. The accuracy of using gestational age-specific reference levels was similar to that of using a categorical threshold.

Fetal magnetic resonance imaging in the evaluation of fetuses referred for sonographically suspected abnormalities of the corpus callosum.

Abstract: Objective. Fetal magnetic resonance imaging (MRI) has been shown to be useful in assessing the developing central nervous system. However, its utility in specific brain disorders has not been well investigated. We hypothesized that fetal MRI can better assess the integrity of the brain in cases with sonographically suspected callosal abnormalities. Methods. We retrospectively reviewed fetal MRI and prenatal sonographic studies of 10 fetuses referred for MRI for sonographically suspected callosal abnormalities. Results. An abnormal corpus callosum was identified on fetal MRI in 80% of cases. The type of callosal abnormality (complete or partial agenesis) was similar on both prenatal sonography and fetal MRI in all cases. All sonographically identified additional brain abnormalities were detected on fetal MRI, with the exception of choroid plexus cysts. Furthermore, in 63% (5 of 8) of cases with a callosal abnormality on both sonography and fetal MRI, additional brain abnormalities were detected on fetal MRI that were not apparent on sonography. These sonographically occult findings were confirmed on postnatal MRI or autopsy in 3 of 5 patients. Conclusions. Fetal MRI is an important adjunct to sonography in assessing the corpus callosum and other aspects of brain development when agenesis of the corpus callosum is suspected. It can identify frequent additional findings that are not visible on sonography such as abnormal sulcation. In light of the association between additional brain abnormalities and worse neurodevelopmental outcome, the potential of fetal MRI as an important

Three- and 4-dimensional ultrasound in obstetric practice: does it help?

Abstract: Objective The purpose of this article was to review the published literature on 3-dimensional ultrasound (3DUS) and 4-dimensional ultrasound (4DUS) in obstetrics and determine whether 3DUS adds diagnostic information to what is currently provided by 2-dimensional ultrasound (2DUS) and, if so, in what areas. Methods A PubMed search was conducted for articles reporting on the use of 3DUS or 4DUS in obstetrics. Seven-hundred six articles were identified, and among those, 525 were actually related to the subject of this review. Articles describing technical developments, clinical studies, reviews, editorials, and studies on fetal behavior or maternal-fetal bonding were reviewed. Results Three-dimensional ultrasound provides additional diagnostic information for the diagnosis of facial anomalies, especially facial clefts. There is also evidence that 3DUS provides additional diagnostic information in neural tube defects and skeletal malformations. Large studies comparing 2DUS and 3DUS for the diagnosis of congenital anomalies have not provided conclusive results. Preliminary evidence suggests that sonographic tomography may decrease the examination time of the obstetric ultrasound examination, with minimal impact on the visualization rates of anatomic structures. Conclusions Three-dimensional ultrasound provides additional diagnostic information for the diagnosis of facial anomalies, evaluation of neural tube defects, and skeletal malformations. Additional research is needed to determine the clinical role of 3DUS and 4DUS for the diagnosis of congenital heart disease and central nervous system anomalies. Future studies should determine whether the information contained in the volume data set, by itself, is sufficient to evaluate fetal biometric measurements and diagnose congenital anomalies.

Sonographic evaluation of upper extremity deep venous thrombosis.

Abstract: Objective The purpose of this presentation is to review the techniques of performing an upper extremity Doppler examination, in addition to illustrating the sonographic appearances of acute and chronic upper extremity deep venous thrombosis (UEDVT). Methods The risk factors and complications of UEDVT are discussed, and the anatomy of the upper extremity deep venous system as well as examination techniques are described. Cases of acute and chronic deep venous thrombosis were also chosen to illustrate the spectrum of sonographic appearances. Results Color Doppler sonography is accurate in the diagnosis of UEDVT. However, in cases of equivocal Doppler findings, or when the sonographic findings are normal but clinical suspicion for central venous thrombosis is high, magnetic resonance or contrast venography is necessary for further evaluation. Conclusions Color Doppler sonography is a rapid and noninvasive technique in the evaluation of venous disease in the upper extremity and is the modality of choice in screening for UEDVT.

Flow Pattern and Vascular Resistive Index as Predictors of Malignancy Risk in Thyroid Follicular Neoplasms

Abstract: OBJECTIVES The purpose of this study was to evaluate whether flow pattern and resistive index (RI) are useful parameters for distinguishing benign from malignant thyroid follicular neoplasms (FNs). METHODS Eighty-six thyroid nodules that underwent sonographically guided fine-needle aspiration and were diagnosed as cases of FN were evaluated by power and duplex Doppler sonography. Pathologic correlation was available for all nodules. The flow pattern seen via power Doppler examination was ranked for each nodule on a scale of 0 to 4, in increasing flow order. For each nodule, the RI value was considered the average of 1 to 3 values obtained with different flow signals. RESULTS Ten nodules (11.63%) were malignant (3 follicular carcinomas, 5 follicular variants of papillary carcinoma, and 2 papillary carcinomas). Fourteen nodules (16.27%) were adenomas, and 62 (72%) were non-neoplastic nodules. The average RI in non-neoplastic nodules was 0.588 (P < .001, chi(2) test): 0.662 in adenomas and 0.763 in malignant nodules. None of the nodules had flow pattern type 0. Flow patterns 1 and 2 (peripheral flow only or predominantly) were present in 58 non-neoplastic nodules (93.5%), 10 adenomas (71.4%), and 2 malignant nodules (20%). Flow pattern type 3 (predominantly central flow) was present in 7 malignant nodules (70%), 4 adenomas (28.6%), and 4 non-neoplastic nodules (6.5%). Only 1 nodule, a papillary carcinoma, had flow pattern type 4 (internal flow only). CONCLUSIONS In FNs, there were significant positive associations between predominantly central flow and malignancy and between predominantly peripheral flow and benign disease (P < .0001, Fisher exact test). However, power Doppler characteristics could not be used to rule out malignancy because 20% of malignant nodules had predominantly peripheral flow. For predicting malignancy, an RI cutoff of 0.75 had good accuracy, specificity, and negative predictive value but had low sensitivity and positive predictive value (respectively, 91%, 97%, 92%, 40%, and 67%). Resistive index values in non-neoplastic nodules were lower than in adenomas and malignant nodules (P < .001, chi(2) test).

Middle Cerebral Artery Peak Systolic Velocity Technique and Variability

Abstract: Objective The aim of this work was to review the use of middle cerebral artery peak systolic velocity (MCA PSV) for the diagnosis of fetal anemia. Methods With the use of a computerized database (MEDLINE), articles on the diagnosis of fetal anemia with ultrasonography were reviewed. Other pertinent references were obtained from the references cited in these articles. In addition, my own institution's clinical experience of the past 18 years was reviewed. Results Several ultrasonographic parameters have been used to diagnose noninvasive fetal anemia. On the basis of robust data, the MCA PSV is the best ultrasonographic parameter used in the management of fetuses at risk for anemia due to different causes. It is also superior to amniocentesis for the diagnosis of fetal anemia in cases of red cell alloimmunization. Conclusions Middle cerebral artery peak systolic velocity is effective for diagnosis of noninvasive moderate and severe fetal anemia. This parameter should not yet be considered the global standard of care for diagnosis of fetal anemia because incorrect use by an inexperienced operator may cause more harm than good; however, if there is a reasonably close medical center with sonographers or sonologists trained to assess the MCA PSV, patients at risk for fetal anemia should be referred to this center.

The Sonographic and Color Doppler Features of Retained Products of Conception

Abstract: Objective. The purpose of this study was to identify the sonographic features of retained products of conception (RPOCs). Methods. Cases of clinically suspected RPOCs referred for pelvic sonography between September 1994 and July 2001 were identified. Patient age, indication, gestational age at delivery, and days postpartum were recorded and sonographic findings were reviewed. Outcomes were determined from medical records and pathology reports. Results. One hundred sixty-three cases were identified. Indications for pelvic sonography included vaginal bleeding in 82 (50%), pelvic pain in 77 (47%), and fever in 55 (34%). Gestational age at delivery ranged from 14 to 43 weeks (mean, 37 weeks), and the sonographic examination was performed from 0 to 95 days postpartum (mean, 21 days). Thirty-six patients underwent surgical intervention, and 28 of these had RPOCs. The remaining 127 patients were followed clinically. An endometrial mass was the most sensitive (79%) and specific (89%) sonographic feature for RPOCs. The isolated finding of either complex fluid in the endometrial canal or a thick endometrium measuring greater than 10 mm had low sensitivity, specificity, and negative and positive predictive values. None of the patients with RPOCs had normal sonographic findings. The absence of an endometrial mass or complex fluid and an endometrial thickness of less than 10 mm were considered normal findings. Color Doppler flow was detected in the endometrium somewhat more often when RPOCs were present than in the absence of RPOCs (75% versus 40%). Conclusions. An endometrial mass is the most sensitive finding for RPOCs. If no mass

Sonographic evaluation of optic nerve diameter in children with raised intracranial pressure.

Abstract: OBJECTIVE The optic nerve is part of the central nervous system, and a rise in intracranial pressure (ICP) can directly affect the perioptic nerve space, leading to an increase in nerve diameter. Transorbital sonography is a safe and easy-to-perform method to measure optic nerve diameter for rapid diagnosis of increased ICP. METHODS The optic nerve diameter was measured in 3 individual occasions by transorbital sonography in the transverse view, 3 mm posterior to the papilla in both eyes, and the mean was calculated. Two groups were examined: a control group of children with normal ICP and normal ophthalmologic and optic nerve examination results and a case group with increased ICP as determined by an alternative method. RESULTS The sample consisted of 156 children, of which 78 (50%) were in the case group and 78 (50%) were in the control group. Eighty-four subjects (53.7%) were male, and 72 (46.1%) were female. The mean +/- SD ages were 6.9 +/- 5.6 years in the case group and 6.8 +/- 5.5 years in the control group. The mean optic nerve diameters were 5.6 +/- 0.6 mm (range, 4.55 +/- 0.7 to 7.6 +/- 0.6 mm) in the case group and 3.3 +/- 0.6 mm (range, 2 +/- 0.6 to 4.35 +/- 0.6 mm) in the control group. The difference in the means was significant at P < .001. CONCLUSIONS Optic nerve diameter, measured by transorbital sonography, was significantly greater in pediatric patients with increased ICP compared with a control group. Transorbital sonography can be used to identify pediatric patients with raised ICP.

Contrast-enhanced sonographic imaging of lymphatic channels and sentinel lymph nodes.

Abstract: Objective. The purpose of this study was to determine whether lymphatic channels (LCs) and sentinel lymph nodes (SLNs) could be detected on sonographic imaging after subcutaneous, submucosal, or parenchymal injections of a sonographic contrast agent (ie, lymphosonography) in a variety of anatomic locations in several animal models. Methods. Eight swine, 7 canines, 4 rabbits, and a monkey were used for these evaluations. Gray scale pulse inversion harmonic imaging of the LCs and the SLNs was performed after subcutaneous (n = 58), submucosal (n = 14), or parenchymal (n = 8) injections of a tissue-specific sonographic contrast agent (Sonazoid; GE Healthcare, Oslo, Norway). In many instances, blue dye was injected into the same locations as Sonazoid, and surgical dissection of the SLNs and LCs was performed for comparison. Scanning electron microscopy (SEM) of contrast-enhanced and control lymph nodes from 2 rabbits was performed to determine the mechanism of contrast agent uptake and retention within SLNs. Results. After subcutaneous, submucosal, or parenchymal contrast agent injections, gray scale pulse inversion harmonic imaging could be used to identify the number and location(s) of LCs and SLNs. After subcutaneous, submucosal, or parenchymal contrast agent injections, Sonazoid was confined to the SLNs (ie, contrast enhancement was not detected in the second-echelon nodes). There was good agreement between the results of lymphosonography and blue dye with surgical dissection in identifying the regional LCs and SLNs. Scanning electron microscopy identified vacuoles representing intact contrast microbubbles within contrast-enhanced SLN macrophages, which were not present in the control lymph nodes. Conclusions. Lymphosonography can be used to detect lymphatic drainage pathways and SLNs in a variety of animal models.

The common ultrasonographic features of pilomatricoma.

Abstract: Objectives. The purpose of this series was to describe typical ultrasonographic features of 20 cases of pilomatricoma and to improve its diagnostic rate with the use of an ultrasonographic approach. Methods. For 20 pilomatricomas in 19 patients with preoperative ultrasonography from 1995 to 2004, we reviewed age, sex, symptoms, duration, referring clinician, and tumor sites. The ultrasonographic findings were retrospectively analyzed for tumor location, shape, size, margin, echo texture, echogenicity, presence, amount, and shape of calcification, presence of a hypoechoic rim, and Doppler flow pattern. Results. The mean age of the 19 patients was 6.9 years (range, 1‐21 years), and the female-male ratio was 1.1:1. Patients had a painful palpable mass in 10 cases (50%). Nine lesions occurred in the neck, 5 in the cheek, 2 in the preauricular region, and 4 in the extremity. All tumors were located in the subcutaneous layer. The mean size of the tumors was 13.4 mm. Fourteen pilomatricomas (70%) appeared as well-defined oval masses. Tumors were heterogeneously hyperechoic in 80% of cases. All tumors had internal echogenic foci. A hypoechoic rim was seen in 17 cases (85%). Doppler flow signals were observed in the peripheral region in 14 cases (70%). A correct preoperative diagnosis was made in 33% on the basis of clinical findings and in 76% by ultrasonography. Conclusions. Diagnosis of pilomatricoma should be considered when a well-defined mass with inner echogenic foci and a peripheral hypoechoic rim or a completely echogenic mass with strong posterior acoustic shadowing in the subcutaneous layer of the head, neck, or extremity is found on ultra

Real-time sonographic imaging for periradicular injections in the lumbar spine: a sonographic anatomic study of a new technique.

Abstract: Objective. We conducted this study to develop a sonographically guided approach to the spinal nerve of the lumbar spine and to assess its feasibility and accuracy by means of computed tomography (CT). Methods. Fifty sonographically guided approaches at 5 levels (L1‐S1) were performed on 5 embalmed cadavers, which were positioned prone. The spinal nerves of the lumbar spine were shown under sonographic guidance. In 1 cadaver, the most lateral aspect of the roof of the intervertebral foramen was defined as a reference point. Its position was computed as a distance from the tip of the spinal process (A), the midline (B), and the intervertebral disk (C). Subsequently, axial transverse CT scans were made to verify these distances. In a second part of the experiment, a spinal needle was advanced under sonographic guidance to the spinal nerves for each lumbar spinal level on 1 embalmed cadaver. The exact placement of the needle tips was checked with the help of CT. Results. This technique for a sonographically guided approach to the periradicular area proved to be feasible and accurate. Sonography and CT provided the same mean measurements of 4.0, 2.5, and 1.4 cm for distances A, B, and C, respectively. The Pearson correlation coefficient was 0.99 (P < .001) between sonography and CT. In the experimental study, all 10 needle tips were placed periradicular to the spinal nerves. Conclusions. Sonographic guidance is a useful adjunct to increase the safety and efficacy of peri

Teaching medical students diagnostic sonography.

Abstract: Objective The purpose of this pilot project was to train medical students in sonography. Methods Thirty-three medical students participated in a pilot sonography course, which included exposure to ultrasound physics, knobology of a compact ultrasound scanner, training in scanning and anatomy of the aorta and right kidney, and reading assignments in these areas. Pretraining and posttraining examinations were given in these areas to analyze the degree of knowledge gained by these methods. Results Nearly all of the medical students increased their basic knowledge of sonography and improved their scanning skills. The improvement was statistically significant in all areas. Conclusions Training in sonography for medical students could be used as a foundation for later, more specialty-specific training to improve the overall medical sonography skills for all physicians.

Ruptured abdominal aortic aneurysm: categorization of sonographic findings and report of 3 new signs.

Abstract: Objective The purpose of this study was to categorize the sonographic findings seen in patients with a ruptured abdominal aortic aneurysm (AAA) and to describe 3 previously undescribed sonographic findings. Methods From January 1997 to December 2003, we evaluated 388 consecutive patients with an AAA (transverse aortic diameter >30 mm). Among these patients, 29 had surgical or computed tomographic demonstration of aneurysm rupture. The remaining 359 were asymptomatic and had no evidence of AAA rupture at follow-up. Results Findings recognized among 29 positive cases included AAA deformation (n = 12), luminal thrombus inhomogeneity (n = 20), clear interruption of a luminal thrombus (n = 5), retroperitoneal hematoma (n = 22), and hemoperitoneum (n = 11). In addition, 3 previously unreported findings were noted: an intraluminal floating thrombus layer (n = 8), a parietal hypoechoic focus due to aneurysm wall interruption (n = 3), and a para-aortic hypoechoic area adjacent to the bleeding side (n = 4). Aside from AAA deformation and thrombus heterogeneity, no other signs were recognized among subjects with a nonruptured aneurysm. Conclusions In the past, sonography has been used mainly to rapidly confirm aneurysm presence in the clinical setting of a patient with a suspected rupture. Instead, this retrospective series shows how this imaging technique can frequently identify several direct and indirect signs of aneurysm rupture itself. Moreover, 3 new indicators of AAA rupture have been observed.

Rates of malignancy in incidentally discovered thyroid nodules evaluated with sonography and fine-needle aspiration.

Abstract: Objective. The purpose of this study was to compare the rate of malignancy in thyroid nodules discovered incidentally on magnetic resonance imaging, computed tomography, and sonography with the rate of malignancy in nonincidentally discovered nodules. Methods. All thyroid sonographic and fine-needle aspiration (FNA) procedures performed during a 6-month period were retrospectively reviewed. Study indications were categorized as incidental (thyroid nodules found on magnetic resonance imaging, computed tomography, or sonography performed for nonthyroid indications) or nonincidental (studies prompted by abnormal physical examination findings or laboratory values or signs or symptoms suggestive of thyroid disease). Rates of malignancy in patients with incidentally discovered nodules were compared with rates in patients with nonincidental thyroid abnormalities by the Fisher exact test. Results. Of 225 thyroid sonographic studies, 35 (16%) were performed for incidentally discovered thyroid nodules, and 190 (84%) were performed for evaluation of nonincidental thyroid abnormalities. A total of 21 patients (60%) in the incidental group and 90 patients (47%) in the nonincidental group underwent FNA. The rate of malignancy in nodules examined by biopsy in the incidental group was 17% compared with 3% in the nonincidental group (P = .020). Patient sex, multiplicity of nodules, nodule size, echo texture, and presence of calcifications did not differ significantly between the groups. The mean age of patients in the incidental group was significantly higher (61 versus 51 years; P = .007); however, advanced age was not associated with a greater rate of malignancy. Conclusions. This study identified an unexpectedly high rate of malignancy in incidentally discovered thyroid nodules, suggesting that incidentally discovered thyroid nodules should be evaluated with follow-up thyroid sonography and FNA.

A magnetic resonance imaging-compatible, large-scale array for trans-skull ultrasound surgery and therapy.

Abstract: Objective. Advances in ultrasound transducer array and amplifier technologies have prompted many intriguing scientific proposals for ultrasound therapy. These include both mildly invasive and noninvasive techniques to be used in ultrasound brain surgery through the skull. In previous work, it was shown how a 500-element hemisphere-shaped transducer could correct the wave distortion caused by the skull with a transducer that operates at a frequency near 0.8 MHz. Because the objective for trans-skull focusing is its ultimate use in a clinical context, a new hemispheric phased-array system has now been developed with acoustic parameters that are optimized to match the values determined in preliminary studies. Methods. The transducer was tested by focusing ultrasound through ex vivo human skulls and into a brain phantom by means of a phase-adaptive focusing technique. Simultaneously, the procedure was monitored by the use of magnetic resonance guidance and thermometry. Results. The ultrasound focus of a 500-element 30-cm-diameter, 0.81-MHz array could be steered electronically through the skull over a volume of approximately 30 × 30 × 26 mm. Furthermore, temperature monitoring of the inner and outer surfaces of the skull showed that the array could coagulate targeted brain tissue without causing excessive skull heating. Conclusions. The successful outcome of these experiments indicates that intensities high enough to destroy brain tissue can be produced without excessive heating of the surrounding areas and without producing large

Sonographic Assessment of the Normal Limits and Percentile Curves of Liver, Spleen, and Kidney Dimensions in Healthy School-Aged Children

Abstract: Objective The purpose of this study was to determine the normal standards of liver, spleen, and kidney dimensions and the relationship of each with sex, age, body weight, height, body mass index, and body surface area in healthy school-aged children. Methods Seven hundred twelve healthy school-aged children (7-15 years) in 2 neighboring cities, including rural areas and city centers, were evaluated prospectively. Sex, age, weight, height, body mass index, and body surface area were determined for each case. Organ dimensions were measured 3 times, and the mean values were recorded. All measured organs had a normal position, shape, and echo texture. The children were separated into 5 groups according to body weight. Results There were no significant differences in organ dimensions with respect to sex (P > .05). The mean right kidney length was shorter than the left kidney length, and the difference was significant (P = .009). Body weight showed the best correlation with liver, spleen, and kidney dimensions. The results were also supported by the variance and covariance of the correlation coefficients. Conclusions The normal limits of the liver, spleen, and kidneys are important parameters during a sonographic examination. This study revealed that organ dimensions showed the best correlation with body weight. To our knowledge, in clinical practice there are no pediatric organ dimension percentile graphs for interpretation of sonographic examinations. We hope this study contributes to daily practice in radiology clinics.

Ultrasonography in tarsal tunnel syndrome.

Abstract: Objective The purpose of this study was to clarify the diagnostic value of ultrasonography in tarsal tunnel syndrome. Methods Seventeen patients (17 feet) with tarsal tunnel syndrome were treated between 1988 and 2003. Preoperative ultrasonography was performed, and the cause of the syndrome was confirmed intraoperatively in all cases. Long and short axes of the tarsal tunnel were scanned to ascertain the presence of any space-occupying lesion. Results The causes of tarsal tunnel syndrome, as confirmed by surgery, were ganglia (n = 10), talocalcaneal coalition (n = 1), talocalcaneal coalition associated with ganglia (n = 3), and varicose veins (n = 3). Among the cases involving ganglia, hypoechoic or anechoic regions were observed. The mean sizes +/- SD of these regions were 19.4 +/- 8.8 mm in the long axis, 15.2 +/- 6.3 mm in the short axis, and 10.4 +/- 3.8 mm in depth. Of these, 3 ganglia were not clearly palpable before surgery and were small: 10 x 10 x 7, 13 x 11 x 9, and 9 x 8 x 7 mm. Among the cases involving talocalcaneal coalition, ultrasonography indicated a beak-shaped bony process on the short axis images. Although these 3 cases were associated with ganglia, this could not be determined by preoperative palpation. Conclusions As a diagnostic imaging technique for tarsal tunnel syndrome, ultrasonography is extremely useful for identifying space-occupying lesions. Ultrasonography should be performed routinely in patients with suspected tarsal tunnel syndrome.

First-Trimester Cesarean Scar Pregnancy Evolving Into Placenta Previa/Accreta at Term

Abstract: Placenta accreta is a rare but serious obstetric condition that is associated with considerable maternal morbidity and mortality. 1 A preoperative diagnosis of placenta accreta is difficult, and it is usually established at cesarean delivery or on histologic examination after obstetric hysterectomy for post-partum hemorrhage. In women with placenta previa, an abnormally adherent placenta is suspected when there is an absent decidual interface between the placenta and the myometrium. Another sign is the presence of unusually dilated vessels at the placental site. 2 , 3 Although the reported accuracy of sonographic diagnosis in the third trimester is reasonably high, late detection is of limited value because it does not prevent the serious complications of placenta accreta. The first-trimester diagnosis of pregnancy implantation in a previous cesarean delivery scar has been reported in recent years. 4 , 5 This condition is difficult to differentiate from cervical pregnancy, and it is likely that before the use of high-resolution transvaginal sonography, cesarean scar pregnancies were diagnosed and treated as cervical ectopic pregnancies. Cervical pregnancies rarely progress to term, whereas cesarean scar pregnancies may do so because of their position at the level of the internal os. In 60% to 70% of cesarean scar pregnancies, there is clear evidence of trophoblast penetrating the endometrial-myometrial junction. It has been postulated that first-trimester cesarean scar pregnancies that invade the myometrium may develop into placenta previa/accreta if the pregnancy is allowed to progress. 5 In this report, we describe the case of a first-trimester cesarean scar pregnancy with evidence of myometrial involvement that was managed expectantly and developed into placenta previa/accreta at term.

How sonographic tomography will change the face of obstetric sonography: a pilot study.

Abstract: Objective. This study was undertaken to determine whether 3-dimensional (3D) volume sonography (sonographic tomography) can yield a far quicker and equally accurate anatomic examination of the second-trimester fetus compared with traditional 2-dimensional (2D) scanning. Methods. Twenty-five consecutive second-trimester fetuses with normal structural surveys on standard 2D imaging underwent 5 standard 3D volume acquisitions each (in the regions of the head, chest, abdomen, face, and lower extremities) immediately after the 2D scan. The 2D and 3D images were subsequently compared in relation to the completeness of the fetal survey, measurements of the biparietal diameter and femur length, and time required to obtain the fetal survey. Results. The structural surveys were complete in 20 of 25 cases using 3D reconstructed volumes. One fetus had an incomplete evaluation of the face on 3D volumes (and limited on 2D imaging because of the prone position of the fetus). The other 4 fetuses with incomplete surveys done on 3D volumes had missing images of a hand or foot. Three-dimensional reconstructions slightly overmeasured the biparietal diameter compared with the 2D reference standard (mean difference, 1.1 mm; P <.001). For femur length, the mean difference was not statistically significant. It took a mean time of 1.1 minutes to obtain the 3D volumes and 5.5 minutes to reconstruct the complete surveys by the 3D volume method. With the standard 2D technique, the structural surveys were done in a mean time of 13.9 minutes. The mean time difference between both methods was 7.3 minutes (P = 2.4 x 10 - 9 ). Conclusions. Using 3D volume acquisition, it is feasible to perform and interpret a structural survey in half the time in which a 2D survey is performed. Further research is necessary to standardize the acquisition of volumes to minimize artifacts and produce uniform images.

Characterization of breast masses with sonography: can biopsy of some solid masses be deferred?

Abstract: Objective. To determine whether sonography can be used to categorize some solid breast masses as probably benign so that biopsy can be deferred. Methods. We prospectively characterized 844 sonographically visible solid breast masses referred for biopsy. Mammographic and sonographic features of the masses were recorded, and all masses were categorized by American College of Radiology Breast Imaging Reporting and Data System classification before biopsy. Of the 844 masses, 148 were categorized as probably benign (Breast Imaging Reporting and Data System category 3). Sonographically guided biopsy (n = 804) or fine-needle aspiration (n = 40) was performed for pathologic correlation. Results. Of the 148 masses that met the sonographic criteria for probably benign masses, there was 1 malignancy, for a negative predictive value of 99.3%. Conclusions. Follow-up can be an acceptable alternative to biopsy for sonographically probably benign solid masses.

Diagnosing Carotid Stenosis by Doppler Sonography State of the Art

Abstract: Objective. The goal of this review article is to present the state of the art in the clinical applications and technical performance and interpretation of carotid sonographic examinations. Methods. Relevant publications regarding color and duplex Doppler sonography (CDDS) of the carotid arteries extracted from a computerized database (MEDLINE) and from references cited in these articles not appearing on the Internet were reviewed. Results. The ability to quickly and efficiently identify stenosis in the carotid artery is an important goal for clinicians and vascular surgeons. Identification of potentially treatable carotid stenosis enables selection of appropriate candidates for endarterectomy or stent implantation. Advances in performance and interpretation of carotid sonographic studies over the last 20 years have been driven by technological improvements in gray scale and CDDS examinations and have made carotid sonography an important means to reach this goal. On the basis of CDDS, intimamedia thickness measurements and plaque location and characterization on gray scale imaging, flow disturbance and areas of stenosis on color Doppler sonography, and flow velocities on spectral Doppler sonography are obtained. The degree of the diameter of a stenosis of the internal carotid artery is the main parameter used for therapeutic approaches. Advantages and limitations of the method are included. Conclusions. Carotid sonography is a unique imaging method for the investigation of carotid abnormalities. Noninvasive, accurate, and cost-effective, it provides morphologic and functional information. It is increasingly becoming the first and often the sole imaging study before endarterectomy, whereas costly and invasive procedures are reserved for special cases.

The use of contrasted transvaginal sonography in the diagnosis of gynecologic diseases: a preliminary study.

Abstract: Objective The purpose of this study was to evaluate the efficacy of a new contrast-dedicated ultrasound technology, contrast-tuned imaging (CnTI), implemented on an endovaginal probe and using the second-generation contrast agent SonoVue (Bracco International BV, Amsterdam, the Netherlands), compared with the standard ultrasound examination in different gynecologic diseases. Methods Eighty-nine patients were enrolled in the study in 4 different clinical centers. The study included 40 patients with uncertain pelvic adnexal masses, 10 patients with pelvic masses indicative of recurrences of gynecologic tumors, 26 patients with uterine pathologic features, and 13 patients with cervical lesions. Results Application of CnTI technology after the SonoVue injection gave a picture of the intralesional microvascularization dramatically different from that obtained during color Doppler examination. Of the 40 pelvic masses, 15 (37.5%) were considered benign and 25 (62.5%) were considered malignant at B-mode and color Doppler examinations. Contrast-enhanced sonography showed no intralesional contrast perfusion in 11 (73%) of 15 cases, and all these were benign at final diagnosis. Of the 4 (27%) cases that had perfusion, 2 were malignant. Conversely, of the 25 cases with positive findings at color Doppler examination and therefore expected to show the appearance of contrast tissue-filling morphologic characteristics, 13 (52%) were malignant at final diagnosis. For evaluation of uterine pathologic features, the CnTI-SonoVue technology did not appear to be superior to the B-mode and color Doppler examinations; however, for the evaluation of cervical cancer, CnTI-SonoVue technology revealed a better definition of the margins of the neoplastic lesions in 4 (40%) of 10 cases. Conclusions In the evaluation of uncertain pelvic masses, the CnTI technology led to an improvement in the ability of the practitioner to differentiate benign from malignant adnexal lesions.