Search results for "Sound"
showing 10 items of 1845 documents
Localization of small islet-cell tumors. Preoperative and intraoperative ultrasound, computed tomography, arteriography, digital subtraction angiogra…
1985
A total of 42 islet-cell tumors were examined between 1972 and 1984. Problems of localization were only encountered in 31 tumors less than 2 cm in diameter. Of 31 small tumors, 27 were correctly localized using a combined diagnostic approach: ultrasound was successful in 12/20 tumors, CT in 9/21, angiography in 20/31, intraarterial digital subtraction angiography in 1/2, and pancreatic venous sampling in 13/16. The smallest tumor found by ultrasound and CT was 7 mm in diameter. Intraoperative ultrasound demonstrated all 9 insulinomas examined. Currently, the most useful techniques for localizing small islet-cell tumors are ultrasound, CT, and angiography. CT is particularly useful for tumor…
CT and MR imaging of chemotherapy-induced hepatopathy.
2019
Chemotherapy-induced hepatopathy includes a wide variety of parenchymal and vascular hepatic changes on imaging, including diffuse or focal hepatopathies (i.e. hepatitis, steatosis, fibrosis, pseudocirrhosis, or sinusoidal obstruction). These changes can profoundly alter the hepatic parenchyma on imaging and result in both false negative and false-positive diagnoses of hepatic metastases and lead to errors in patient management strategies. It is therefore important for radiologists to have a comprehensive knowledge of the imaging patterns that may develop following chemotherapy. The purpose of this review is to explore the broad spectrum of hepatic parenchymal and vascular chemotherapy-indu…
Interrater reliability of ultrasound in the diagnosis of sialolithiasis
2019
The aim of this study was to assess the interrater reliability of ultrasound for diagnosing sialolithiasis. A total of 100 consecutive patients with signs of obstructive sialadenopathy were evaluated. The patients all underwent ultrasound examinations in a standardized manner conducted by one specialist with extensive experience in the management of salivary gland disorders and proficiency in head and neck ultrasonography. The video recordings were sent to six colleagues with comparable experience without providing any further information about the patients' medical history and physical examination. The overall agreement between the seven observers was substantial, with a κ of 0.765 for th…
Poor Bone Quality in Patients With Amyotrophic Lateral Sclerosis
2020
Objective: Musculoskeletal functional deterioration in Amyotrophic lateral sclerosis (ALS) is associated with an increase in bone fractures. The purpose of this study was to evaluate the influence of sex, ALS type, on bone quality in patients with ALS compared to healthy controls. The impact on bone health of the clinical status and some metabolic parameters was also analyzed in ALS patients.Methods: A series of 33 voluntary patients with ALS, and 66 healthy individuals matched in sex and age underwent assessment of bone mass quality using quantitative ultrasound (QUS) of the calcaneus. Ultrasonic broadband attenuation (BUA), the speed of sound (SOS), stiffness index and T-score were measur…
Tomographic left ventricular volume determination in the presence of aneurysm by three-dimensional echocardiographic imaging. I: Asymmetric model hea…
1996
To improve the accuracy of measurements of left ventricular volume in the presence of an aneurysm, we used three-dimensional echocardiographic imaging to analyze the shape of left ventricles in 23 asymmetric model hearts with eccentric aneurysms of different sizes, shapes, and localizations. A standard 3.75 MHz ultrasound probe with a rotation motor device was used to obtain a three-dimensional data set. By rotating the probe stepwise 1 degree, 180 radial ultrasound pictures were digitized. On the basis of the three-dimensional data set, the following parameters were determined and compared with the dimensions of the model hearts obtained by direct measurement: total left ventricular volume…
Rectal advancement flaps for the treatment of transphincteric perianal fistulas: a three-dimensional endoanal ultrasound and quality of life assessme…
2020
This study quantifies the damage to the internal anal sphincter (IAS) after a rectal mucosal advancement flap for a high transphincteric fistula in 16 patients using 3D-endoanal ultrasound. This was correlated with postoperative incontinence and quality of life scores. The median length of involved IAS preoperatively was 50 % (20-100) and 93.72 % for EAS (47.4-100 %). IAS division did not influence continence (p > 0.05). Continence deteriorated between the pre-, postoperative (p = 0.014) and six-month follow-up (p = 0.005), with no significant differences after one year (p > 0.05). The FIQOL score and SF-36 deteriorated initially, with recovery in all domains except for mental health after …
Sonographische Darstellbarkeit und Größenbestimmung von Abdominalorganen bei gesunden Neugeborenen
1988
The determination of organ size is another important criterium in ultrasound examination. There are only few investigations in the neonatal group. Therefore in a prospective study the abdominal organs of 85 neonates were examined with a 7.5 MHz small part scanner. These organs were measured in standardized sections in order to establish normal values]
Right ventricular volume determination in isolated human hearts
1986
For right ventricular volume determination a new method was developed that took into account right ventricular imaging by apical two-dimensional echocardiography in the four- and two-chamber views. Right ventricular volume was calculated by subtraction of the partial volume of the left ventricle and interventricular septum from the total heart volume of the right and left ventricles including the interventricular septum. Accuracy of the subtraction method was evaluated in isolated human hearts by two-dimensional echocardiography and radiography. Regression analysis indicated that for both the echocardiographic and radiologic procedures, the subtraction method gave the best correlation with …
TRANS-FUSIMO - clinical translation of patient specific planning and conduction of FUS treatment in moving organs
2015
The movement of the target challenges the application of high intensive focused ultrasound (HiFU/MRgFUS) for the treatment of malignancies in moving abdominal organs such as liver and kidney. Moreover, the anatomical location of the lesion is often behind the rib cage. The physiology of the organs, the dynamic and complex blood perfusion impairs the energy disposition in the tissue due to the heat transfer within the organ. To explore the full potential of extracorporeal FUS to safely and precisely destroy tissue in the depth of a moving organ requires sophisticated software and advanced hardware. In the EU project FUSIMO (http://www.fusimo.eu) a software demonstrator for the patient specif…