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Sample records for comparative ultrasound biomicroscopic

  1. A New Ultrasound Biomicroscopic Sign seen after Deep Sclerectomy (Dolphin Head Sign)

    PubMed Central

    Abdelrahman, Ahmed M; Cheweikh, Hala M El; Allam, Riham SHM

    2016-01-01

    ABSTRACT Purpose: To describe a new ultrasound biomicroscopic (UBM) sign seen in patients who underwent deep sclerectomy (DS) as a surgical procedure for the management of uncontrolled primary open-angle glaucoma (POAG). The presence of this sign in ultrasound biomicroscopy is suggested to be an indicator of successful surgery. We would like to name this sign as the “dolphin head sign.” Design: Prospective interventional study. Materials and methods: Twenty-eight eyes of 17 patients with POAG underwent DS with intraoperative mitomycin C (MMC) 0.3% applied for 2 minutes under the superficial scleral flap. Patients were followed up for a minimum of 6 months. Ultrasound biomicroscopy was done at the third postoperative month to evaluate the surgical area in both successful and failed cases. Results: The study included 28 eyes of 17 patients. The mean age of the study group was 42.90 ± 14.37 years (20–64 years). The study included 10 females and 7 males. The mean preoperative intraocular pressure (IOP) was 24.57 ± 6.37 mm Hg (20-38 mm Hg). The mean best corrected visual acuity (BCVA) was 0.57 ± 0.3 (0.05–1.00). Complete success has been achieved in 21 eyes (75%) during the follow-up period, with a mean IOP of 12.00 ± 3.86 mm Hg (6–20 mm Hg). The dolphin head sign was demonstrated only in successful cases, whereas the unsuccessful cases failed to show the typical sign. Conclusion: The presence of a “dolphin head” configuration in UBM images could be taken as an indicator of successful DS. How to cite this article: Abdelrahman AM, El Cheweikh HM, El-Fayoumi DMS, Allam RSHM. A New Ultrasound Biomicroscopic Sign seen after Deep Sclerectomy (Dolphin Head Sign). J Curr Glaucoma Pract 2016;10(2):56-59. PMID:27536048

  2. The suitability of the ultrasound biomicroscope for establishing texture in giant cell arteritis

    PubMed Central

    Roters, S.; Szurman, P.; Engels, B.; Brunner, R.

    2001-01-01

    AIM—To establish whether ultrasound biomicroscope (UBM) is a helpful tool in locating the arterial segment responsible in patients with segmental attacks in giant cell arteritis
METHODS—The superficial temporal arteries of 19 patients with suspected giant cell arteritis were examined with the UBM before biopsy.
RESULTS—20 specimens provided the histological proof of giant cell arteritis in five patients. Side differences, a dark perivascular halo, and high reflexivity of the intra-arterial space were found.
CONCLUSION—it is assumed that there are two types of arteritic inflammation: (1) the occlusion of intra-arterial space due to intimal fibrosis (UBM: high reflexive "filling"), and (2) inflammation of the perivascular zone with oedematous thickening and infiltration of the media (UBM: dark halo) and its combination. UBM is helpful in obtaining an indication of the side and segment for biopsy.

 PMID:11466252

  3. Ultrasound biomicroscopic evaluation of anterior segment cysts as a risk factor for ocular hypertension and closure angle glaucoma

    PubMed Central

    Dusak, Abdurrahim; Baykara, Mehmet; Ozkaya, Guven; Erdogan, Cuneyt; Ozcetin, Hikmet; Tuncel, Ercan

    2013-01-01

    AIM To investigate the relationship between the ultrasound biomicroscopic (UBM) features of anterior-segment cysts (ASCs) and increased intraocular pressure (IOP) as a risk factor for closed-angle glaucoma (CAG). METHODS Totally 24 eyes with recently diagnosed ASCs were divided into two groups. First group with ASC and ocular normotension (n=13), second group with ASC and ocular hypertension (n=11). An ophthalmologic examination, including tonometry, slit-lamp biomicroscopy (SLBM), gonioscopy, fundoscopy, pentacam, and UBM, was performed. The features of the ASCs were compared with the IOP. RESULTS ASCs were accurately diagnosed and delineated in 24 eyes using UBM. IOP was elevated in those ASCs with a secondary aetiology (P=0.027), iridociliary location (P=0.006), deformed shape (P=0.013), increased size (P=0.001) and elongated pupillary aperture (P=0.009). However, the count (P=0.343) of ASCs, anterior chamber depth (ACD; P=0.22) and axial lenght (AL; P=0.31) were not associated with ocular hypertension. Correlations were found between the IOP and ASC size (r=-0.712; P=0.003), anterior chamber angle (ACA; r=-0.985; P<0.001), angle opening area (AOA; r=0.885; P<0.001), angulation of iris (r=-0.776, P<0.001), and affected iris quadrant (r =-0.655, P=0.002). CONCLUSION Ocular hypertension in some eyes with ASC might be associated with various mechanisms, including secondary aetiology, iridociliary location, deformed shape, increased size and elongated pupill, which can be determined by UBM. PMID:23991389

  4. Ultrasound biomicroscopic findings of the iridocorneal angle in live healthy and glaucomatous dogs.

    PubMed

    Hasegawa, Takashi; Kawata, Manabu; Ota, Mitsuharu

    2016-01-01

    By using ultrasound biomicroscopy (UBM), the cross-sectional structures of the entire iridocorneal angle (ICA) which are unable to assess with gonioscopic examination were evaluated objectively and quantitatively in live healthy and glaucomatous dogs. The ICAs of normotensive eyes in healthy dogs with normal open angle (NOR), a predisposition to primary closed angle glaucoma (PCAG) (PREDIS) and suffering from unilateral PCAG (UNI), as well as the ICAs of hypertensive eyes with acute and chronic PCAG (ACG and CRG), were assessed. The opening of the ciliary cleft in PREDIS was smaller than that in NOR. In UNI, the opening and area of the ciliary cleft were significantly decreased compared with those of NOR and PREDIS. ACG had widespread structural abnormalities including marked decrease in the ciliary cleft and scleral venous plexus, and a thinner sclera than those in normotensive eyes, whereas the ICA collapsed in CRG with the thinnest sclera. Medical therapy-responsive glaucomatous cases had wider ciliary cleft and scleral venous plexus than unresponsive ones. These findings suggest that the ciliary cleft and scleral venous plexus of the ICA are key structures contributing to not only the pathophysiology of canine glaucoma but also the responsiveness to medical therapy in glaucomatous eyes, and cross-sectional entire structures of the ICA should be evaluated quantitatively with UBM when diagnosing and managing canine glaucoma.

  5. Ultrasound biomicroscopic analysis of iris-fixed acrylic intraocular lens in the absence of capsule support.

    PubMed

    Avitabile, Teresio; Bonfiglio, Vincenza; Castiglione, Francesco; Gagliano, Caterina; Reibaldi, Michele; Pulvirenti, Manuela; Reibaldi, Alfredo

    2012-12-01

    The aim of the study was to investigate postoperative complications and to determine with ultrasound biomicroscopy (UBM) the position of a foldable acrylic intraocular lens (IOL) implanted with a surgical technique of iris suturing in eyes without capsule support. Six eyes with iris-sutured IOLs were examined postoperatively with UBM. The examination included the position of haptics and their relationship to the surrounding structures. Other parameters studied were central anterior chamber depth, IOL iris contact and pigment dispersion. The position of all 12 haptics was determined. All haptics were in touch with the iris. Pigment dispersion was seen in two cases. The anterior chamber depth of the sutured eyes was normal. There was neither cystoid macular edema nor chronic uveitis postoperatively. In conclusion, in most cases surgical placement of iris-fixed lenses is a blind procedure and UBM could be an appropriate method to determine the position of IOL haptics postoperatively and to demonstrate that this surgical technique is reproducible, safe, and effective with the limitation of the difficulty of iris suturing IOL.

  6. 21 CFR 886.1850 - AC-powered slitlamp biomicroscope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered slitlamp biomicroscope. 886.1850... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1850 AC-powered slitlamp biomicroscope. (a) Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is...

  7. 21 CFR 886.1850 - AC-powered slitlamp biomicroscope.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered slitlamp biomicroscope. 886.1850... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1850 AC-powered slitlamp biomicroscope. (a) Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is...

  8. Comparative evaluation of ultrasound scanner accuracy in distance measurement

    NASA Astrophysics Data System (ADS)

    Branca, F. P.; Sciuto, S. A.; Scorza, A.

    2012-10-01

    The aim of the present study is to develop and compare two different automatic methods for accuracy evaluation in ultrasound phantom measurements on B-mode images: both of them give as a result the relative error e between measured distances, performed by 14 brand new ultrasound medical scanners, and nominal distances, among nylon wires embedded in a reference test object. The first method is based on a least squares estimation, while the second one applies the mean value of the same distance evaluated at different locations in ultrasound image (same distance method). Results for both of them are proposed and explained.

  9. Comparing Ultrasound and Mechanical Steering in a Biodiesel Production Process

    NASA Astrophysics Data System (ADS)

    Costa-Felix, Rodrigo P. B.; Ferreira, Jerusa R. L.

    The analysis of the kinetics of the transesterification reaction is crucial to compare different routes or routes with different catalysts or reaction accelerators. The use of ultrasound is considereda method for accelerating the biodiesel production. However, little effort has been done and is reported in the literature about how and under what conditions the use of ultrasound really speeds up the process, or the conditions under which its use is unnecessary or even harmful, burdening the process. Two dissimilar energy injections into a typical route were tested: ultrasound (@ 1 MHz and no heating) and mechanical steering (with heating), both applied in an 8:1 ratio of soybean oil and methanol, adding 1% of KOH as catalyzer. As results, during the first 10 minutes of reaction ultrasound showed unbearable effect on the transesterification, whilst mechanical steering and heating achieved almost 70% of conversion ratio. However, during the following 10 minutes, the mechanical steering and heating got nothing more than 80% of conversion, a considerable less efficient process than ultrasound assisted one, which achieved more than 90%. The straightforward explanation is that ultrasound continually inserts energy in a slower rate, what can result in a more stable conversion scenario. On the other hand, mechanical steering and heating provides more energy at a glance, but cannot push the final conversion rate beyond a limit, as the transesterification is a double-way chemical process. The instability mechanical steering and heating settles in the reaction medium pulls the components back to their original states more than pushes than to the converted equilibrium state of the matter.

  10. Ultrasound

    MedlinePlus

    ... your test will be done. Alternative Names Sonogram Images Abdominal ultrasound Ultrasound in pregnancy 17 week ultrasound ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  11. Ultrasound

    MedlinePlus

    Ultrasound is a type of imaging. It uses high-frequency sound waves to look at organs and ... liver, and other organs. During pregnancy, doctors use ultrasound to view the fetus. Unlike x-rays, ultrasound ...

  12. Three-dimensional ultrasound does not improve diagnosis of retained placental tissue compared to two-dimensional ultrasound.

    PubMed

    Belachew, Johanna; Axelsson, Ove; Eurenius, Karin; Mulic-Lutvica, Ajlana

    2015-01-01

    The study objective was to improve ultrasonic diagnosis of retained placental tissue by measuring the volume of the uterine body and cavity using three-dimensional (3D) ultrasound. Twenty-five women who were to undergo surgical curettage due to suspected retained placental tissue were included. The volume of the uterine body and cavity was measured using the VOCAL imaging program. Twenty-one women had retained placental tissue histologically verified. Three of these had uterine volumes exceeding the largest volume observed in the normal puerperium. Seventeen of the 21 women had a uterine cavity volume exceeding the largest volume observed in the normal puerperium. In all 14 cases examined 28 days or more after delivery the cavity volume exceeded the largest volume observed in the normal puerperium. A large cavity volume estimated with 3D ultrasound is indicative of retained placental tissue. However, 3D ultrasound adds little or no diagnostic power compared to 2D ultrasound.

  13. Comparative efficacy of pregabalin and therapeutic ultrasound versus therapeutic ultrasound alone on patients with post stroke shoulder pain.

    PubMed

    Rahman, M S; Uddin, M T

    2014-07-01

    The study was designed to compare the efficacy of pregabalin, an anticonvulsant on pain behavior of stroke patients with shoulder pain in a comparative study with ultrasound therapy and ultimately to recommend a better treatment option to improve pain and function in post stroke shoulder pain. This study was carried out in a private neurology Hospital in Dhaka during January to December 2010. Data were collected from 70 post stroke patients with shoulder pain and were divided into two groups. The patients in Group A were treated with pregabalin 100mg twice daily along with therapeutic ultrasound 10 minutes daily and group B were treated with therapeutic ultrasound alone for the same dose and duration. Pain free range of motion exercise was given to both groups as the therapeutic exercise. Pain parameters in the form of VAS were measured at one and two weeks and were compared. Seventy one percent of the patients were male with 80% were above 60 years old. Pain scoring in VAS of 100 was 21.32±6.01 in group A and 41±4.58 in groups B at the end of two weeks assuming the pretreatment VAS of all patients as 100. Marked improvement in shoulder pain were observed in both groups and Group A had better improvement in pain than group B. Therapeutic ultrasound when given with pregabalin found to have added benefit over therapeutic ultrasound alone in post stroke shoulder pain. Differences were statistically significant.

  14. Breast imaging with ultrasound tomography: a comparative study with MRI

    NASA Astrophysics Data System (ADS)

    Ranger, Bryan; Littrup, Peter; Duric, Neb; Li, Cuiping; Schmidt, Steven; Lupinacci, Jessica; Myc, Lukasz; Szczepanski, Amy; Rama, Olsi; Bey-Knight, Lisa

    2010-03-01

    The purpose of this study was to investigate the performance of an ultrasound tomography (UST) prototype relative to magnetic resonance (MR) for imaging overall breast anatomy and accentuating tumors relative to background tissue. The study was HIPAA compliant, approved by the Institutional Review Board, and performed after obtaining the requisite informed consent. Twenty-three patients were imaged with MR and the UST prototype. T1 weighted images with fat saturation, with and without gadolinium enhancement, were used to examine anatomical structures and tumors, while T2 weighted images were used to identify cysts. The UST scans generated sound speed, attenuation, and reflection images. A qualitative visual comparison of the MRI and UST images was then used to identify anatomical similarities. A more focused approach that involved a comparison of reported masses, lesion volumes, and breast density was used to quantify the findings from the visual assessment. Our acoustic tomography prototype imaged distributions of fibrous stroma, parenchyma, fatty tissues, and lesions in patterns similar to those seen in the MR images. The range of thresholds required to establish tumor volume equivalency between MRI and UST suggested that a universal threshold for isolating masses relative to background tissue is feasible with UST. UST has demonstrated the ability to visualize and characterize breast tissues in a manner comparable to MRI. Thresholding techniques accentuate masses relative to background anatomy, which may prove clinically useful for early cancer detection.

  15. Ultrasound

    MedlinePlus

    ... called multiples) To screen for birth defects, like spina bifida or heart defects . Screening means seeing if your ... example, if the ultrasound shows your baby has spina bifida, she may be treated in the womb before ...

  16. Ultrasound

    MedlinePlus Videos and Cool Tools

    ... baby's development in the uterus. Ultrasound uses inaudible sound waves to produce a two-dimensional image of the baby while inside the mother's uterus. The sound waves bounce off solid structures in the body ...

  17. Ultrasound detection of pneumothorax compared with chest X-ray and computed tomography scan.

    PubMed

    Nagarsheth, Khanjan; Kurek, Stanley

    2011-04-01

    Pneumothorax after trauma can be a life threatening injury and its care requires expeditious and accurate diagnosis and possible intervention. We performed a prospective, single blinded study with convenience sampling at a Level I trauma center comparing thoracic ultrasound with chest X-ray and CT scan in the detection of traumatic pneumothorax. Trauma patients that received a thoracic ultrasound, chest X-ray, and chest CT scan were included in the study. The chest X-rays were read by a radiologist who was blinded to the thoracic ultrasound results. Then both were compared with CT scan results. One hundred and twenty-five patients had a thoracic ultrasound performed in the 24-month period. Forty-six patients were excluded from the study due to lack of either a chest X-ray or chest CT scan. Of the remaining 79 patients there were 22 positive pneumothorax found by CT and of those 18 (82%) were found on ultrasound and 7 (32%) were found on chest X-ray. The sensitivity of thoracic ultrasound was found to be 81.8 per cent and the specificity was found to be 100 per cent. The sensitivity of chest X-ray was found to be 31.8 per cent and again the specificity was found to be 100 per cent. The negative predictive value of thoracic ultrasound for pneumothorax was 0.934 and the negative predictive value for chest X-ray for pneumothorax was found to be 0.792. We advocate the use of chest ultrasound for detection of pneumothorax in trauma patients.

  18. Estimating the keratoconus index from ultrasound images of the human cornea.

    PubMed

    Castiglione, F; Castiglione, F

    2000-12-01

    The keratoconus index (KI) is a new biometric parameter to make diagnosis and to follow the development of the keratoconus in human eyes. Using images from an ultrasound biomicroscope, we show a semi-automatic method to speed up the computation of the KI.

  19. An adaptive optics biomicroscope for mouse retinal imaging

    NASA Astrophysics Data System (ADS)

    Biss, David P.; Webb, Robert H.; Zhou, Yaopeng; Bifano, Thomas G.; Zamiri, Parisa; Lin, Charles P.

    2007-02-01

    In studying retinal disease on a microscopic level, in vivo imaging has allowed researchers to track disease progression in a single animal over time without sacrificing large numbers of animals for statistical studies. Historically, a drawback of in vivo retinal imaging, when compared to ex vivo imaging, is decreased image resolution due to aberrations present in the mouse eye. Adaptive optics has successfully corrected phase aberrations introduced the eye in ophthalmic imaging in humans. We are using adaptive optics to correct for aberrations introduced by the mouse eye in hopes of achieving cellular resolution retinal images of mice in vivo. In addition to using a wavefront sensor to drive the adaptive optic element, we explore the using image data to correct for wavefront aberrations introduced by the mouse eye. Image data, in the form of the confocal detection pinhole intensity are used as the feedback mechanism to control the MEMS deformable mirror in the adaptive optics system. Correction for wavefront sensing and sensor-less adaptive optics systems are presented.

  20. A pilot study comparing the DuoFertility® monitor with ultrasound in infertile women

    PubMed Central

    Rollason, Jennie CB; Outtrim, Joanne G; Mathur, Raj S

    2014-01-01

    Background The purpose of this study was to assess the accuracy of ovulation detection by the DuoFertility® monitor compared with transvaginal ultrasound in infertile women with regular menstrual cycles. Methods Eight infertile patients, aged 27–40 years, with a body mass index of 19–29, regular menses, normal ovaries on pelvic ultrasound scan, and normal early follicular luteinizing hormone (LH), follicle-stimulating hormone, and prolactin were recruited from infertility clinics in primary and secondary care for this pilot, prospective, observational study. The patients were asked to use the DuoFertility monitor for the whole cycle, with investigators and patients blind to DuoFertility data. Daily urine LH monitoring commenced on cycle day 8, with daily transvaginal ultrasound following the first positive LH until ovulation was observed. Ovulation was further confirmed by serum progesterone. The main outcome measure was detection of ovulation by the DuoFertility monitor, and correlation between day of ovulation assessed by DuoFertility and ultrasound. Results DuoFertility identified ovulation as having occurred within one day of that determined via ultrasound in all cycles. The sensitivity of ovulation detection was 100% (95% confidence interval 82–100). The specificity could not be concluded from the data. Conclusion In infertile women with regular cycles, the DuoFertility monitor appears to accurately identify ovulatory cycles and the day of ovulation. PMID:25075200

  1. Compare ultrasound-mediated heating and cavitation between flowing polymer- and lipid-shelled microbubbles during focused ultrasound exposures.

    PubMed

    Zhang, Siyuan; Zong, Yujin; Wan, Mingxi; Yu, Xiaojun; Fu, Quanyou; Ding, Ting; Zhou, Fanyu; Wang, Supin

    2012-06-01

    This paper compares the efficiency of flowing polymer- and lipid-shelled microbubbles (MBs) in the heating and cavitation during focused ultrasound exposures. Temperature and cavitation activity were simultaneously measured as the two types of shelled MBs and saline flowing through a 3 mm diameter vessel in the phantom with varying flow velocities (0-20 cm/s) at different acoustic power levels (0.6-20 W) with each exposure for 5 s. Temperature and cavitation for the lipid-shelled MBs were higher than those for the polymer-shelled MBs. Temperature rise decreased with increasing flow velocities for the two types of shelled MBs and saline at acoustic power 1.5 W. At acoustic power 11.1 W, temperature rise increased with increasing flow velocities for the lipid-shelled MBs. For the polymer-shelled MBs, the temperature rise increased with increasing flow velocities from 3-15 cm/s and decreased at 20 cm/s. Cavitation increased with increasing flow velocity for the two shelled MBs and there were no significant changes of cavitation with increasing flow velocities for saline. These results suggested that lipid-shelled MBs may have a greater efficiency than polymer-shelled MBs in heating and cavitation during focused ultrasound exposures.

  2. Nonlinear Ultrasound Propagation in Solid ^4{He} Compared with Shear Modulus Experiments

    NASA Astrophysics Data System (ADS)

    Iwasa, Izumi; Kojima, Harry

    2016-10-01

    Ultrasound attenuation (α ) and velocity (V) at 9.6 MHz are measured in polycrystalline hcp ^4{He} . The ultrasound signal above 200 mK is linear and understood in terms of resonant vibration of dislocation segments pinned between network nodes with an average pinning length of 3.7 μ m, much shorter than 59 μ m estimated from a shear modulus measurement. Dramatic changes in α and V are observed below 200 mK. The changes are strongly dependent on temperature and are nonlinear and hysteretic. These effects result from pinning of dislocations by ^3{He} impurities (nominal concentration of 0.3 ppm). The dislocation damping constant due to thermal phonons, the binding energy between dislocation and ^3{He} , and the average network pinning length obtained from the ultrasound data are compared with those from the shear modulus experiments.

  3. Ultrasound and Cadaveric Prosections as Methods for Teaching Cardiac Anatomy: A Comparative Study

    ERIC Educational Resources Information Center

    Griksaitis, Michael J.; Sawdon, Marina A.; Finn, Gabrielle M.

    2012-01-01

    This study compared the efficacy of two cardiac anatomy teaching modalities, ultrasound imaging and cadaveric prosections, for learning cardiac gross anatomy. One hundred and eight first-year medical students participated. Two weeks prior to the teaching intervention, students completed a pretest to assess their prior knowledge and to ensure that…

  4. Comparative kinetic analysis of silent and ultrasound-assisted catalytic wet peroxide oxidation of phenol.

    PubMed

    Rokhina, Ekaterina V; Repo, Eveliina; Virkutyte, Jurate

    2010-03-01

    The kinetic study of silent and ultrasound-assisted catalytic wet peroxide oxidation of phenol in water was performed to qualitatively assess the effect of ultrasound on the process kinetics. Various kinetic parameters such as the apparent kinetic rate constants, the surface utilization coefficient and activation energy of phenol oxidation over RuI(3) catalyst were investigated. Comparative analysis revealed that the use of ultrasound irradiation reduced the energy barrier of the reaction but had no impact on the reaction pathway. The activation energy for the oxidation of phenol over RuI(3) catalyst in the presence of ultrasound was found to be 13kJmol(-1), which was four times smaller in comparison to the silent oxidation process (57kJmol(-1)). Finally, 'figures-of-merit' was utilized to assess different experimental strategies such as sonolysis alone, H(2)O(2)-enhanced sonolysis and sono-catalytic oxidation of phenol in order to estimate the electric energy consumption based on the kinetic rate constants of the oxidation process.

  5. Two Crosslinking Technologies for Superficial Reticular Dermis Injection: A Comparative Ultrasound and Histologic Study

    PubMed Central

    Besse, Stéphanie; Sarazin, Didier

    2017-01-01

    Background: Few hyaluronic acid fillers have been developed for superficial injection. Objective: To compare the diffusion and integration properties of cohesive polydensified matrix and Vycross® technology hyaluronic acid fillers with lidocaine following injection into the superficial reticular dermis. Methods and materials: Two subjects received two injections each of cohesive polydensified matrix and Vycross® hyaluronic acid (0.2mL/site) in the superficial reticular dermis of the buttock under ultrasound control. Biopsies were obtained at Days 0, 15, and/or 90. Ultrasound and histologic analyses were performed, plus a series of simple rheological tests. Results: Day 0 ultrasound images showed cohesive polydensified matrix hyaluronic acid homogeneous with the surrounding dermis. Vycross® hyaluronic acid showed more heterogeneity and some leakage into the hypodermis. Day 15 and Day 90 images were similar to Day 0. Histologic examination of biopsy tissue showed cohesive polydensified matrix hyaluronic acid homogeneously distributed among collagen fibrils with no visible particles. Vycross® hyaluronic acid appeared as variable-sized pools with a particulate appearance. Neither gel was associated with an inflammatory reaction. Laboratory tests showed cohesive polydensified matrix hyaluronic acid to have greater cohesivity and resistance to traction forces than Vycross®. Conclusion: cohesive polydensified matrix gel with lidocaine is homogeneously distributed following injection in the superficial reticular dermis and may be particularly suited for aesthetic indications requiring superficial injection. PMID:28210379

  6. Ultrasound pregnancy

    MedlinePlus

    Pregnancy sonogram; Obstetric ultrasonography; Obstetric sonogram; Ultrasound - pregnancy; IUGR - ultrasound; Intrauterine growth - ultrasound; Polyhydramnios - ultrasound; Oligohydramnios - ultrasound; ...

  7. Transvaginal ultrasound

    MedlinePlus

    ... Uterine bleeding - transvaginal ultrasound; Menstrual bleeding - transvaginal ultrasound; Infertility - transvaginal ultrasound; Ovarian - transvaginal ultrasound; Abscess - transvaginal ultrasound

  8. Investigation of mass transfer intensification under power ultrasound irradiation using 3D computational simulation: A comparative analysis.

    PubMed

    Sajjadi, Baharak; Asgharzadehahmadi, Seyedali; Asaithambi, Perumal; Raman, Abdul Aziz Abdul; Parthasarathy, Rajarathinam

    2017-01-01

    This paper aims at investigating the influence of acoustic streaming induced by low-frequency (24kHz) ultrasound irradiation on mass transfer in a two-phase system. The main objective is to discuss the possible mass transfer improvements under ultrasound irradiation. Three analyses were conducted: i) experimental analysis of mass transfer under ultrasound irradiation; ii) comparative analysis between the results of the ultrasound assisted mass transfer with that obtained from mechanically stirring; and iii) computational analysis of the systems using 3D CFD simulation. In the experimental part, the interactive effects of liquid rheological properties, ultrasound power and superficial gas velocity on mass transfer were investigated in two different sonicators. The results were then compared with that of mechanical stirring. In the computational part, the results were illustrated as a function of acoustic streaming behaviour, fluid flow pattern, gas/liquid volume fraction and turbulence in the two-phase system and finally the mass transfer coefficient was specified. It was found that additional turbulence created by ultrasound played the most important role on intensifying the mass transfer phenomena compared to that in stirred vessel. Furthermore, long residence time which depends on geometrical parameters is another key for mass transfer. The results obtained in the present study would help researchers understand the role of ultrasound as an energy source and acoustic streaming as one of the most important of ultrasound waves on intensifying gas-liquid mass transfer in a two-phase system and can be a breakthrough in the design procedure as no similar studies were found in the existing literature.

  9. Comparing tongue shapes from ultrasound imaging using smoothing spline analysis of variance.

    PubMed

    Davidson, Lisa

    2006-07-01

    Ultrasound imaging of the tongue is increasingly common in speech production research. However, there has been little standardization regarding the quantification and statistical analysis of ultrasound data. In linguistic studies, researchers may want to determine whether the tongue shape for an articulation under two different conditions (e.g., consonants in word-final versus word-medial position) is the same or different. This paper demonstrates how the smoothing spline ANOVA (SS ANOVA) can be applied to the comparison of tongue curves [Gu, Smoothing Spline ANOVA Models (Springer, New York, 2002)]. The SS ANOVA is a technique for determining whether or not there are significant differences between the smoothing splines that are the best fits for two data sets being compared. If the interaction term of the SS ANOVA model is statistically significant, then the groups have different shapes. Since the interaction may be significant even if only a small section of the curves are different (i.e., the tongue root is the same, but the tip of one group is raised), Bayesian confidence intervals are used to determine which sections of the curves are statistically different. SS ANOVAs are illustrated with some data comparing obstruents produced in word-final and word-medial coda position.

  10. Advanced noise reduction in placental ultrasound imaging using CPU and GPU: a comparative study

    NASA Astrophysics Data System (ADS)

    Zombori, G.; Ryan, J.; McAuliffe, F.; Rainford, L.; Moran, M.; Brennan, P.

    2010-03-01

    This paper presents a comparison of different implementations of 3D anisotropic diffusion speckle noise reduction technique on ultrasound images. In this project we are developing a novel volumetric calcification assessment metric for the placenta, and providing a software tool for this purpose. The tool can also automatically segment and visualize (in 3D) ultrasound data. One of the first steps when developing such a tool is to find a fast and efficient way to eliminate speckle noise. Previous works on this topic by Duan, Q. [1] and Sun, Q. [2] have proven that the 3D noise reducing anisotropic diffusion (3D SRAD) method shows exceptional performance in enhancing ultrasound images for object segmentation. Therefore we have implemented this method in our software application and performed a comparative study on the different variants in terms of performance and computation time. To increase processing speed it was necessary to utilize the full potential of current state of the art Graphics Processing Units (GPUs). Our 3D datasets are represented in a spherical volume format. With the aim of 2D slice visualization and segmentation, a "scan conversion" or "slice-reconstruction" step is needed, which includes coordinate transformation from spherical to Cartesian, re-sampling of the volume and interpolation. Combining the noise filtering and slice reconstruction in one process on the GPU, we can achieve close to real-time operation on high quality data sets without the need for down-sampling or reducing image quality. For the GPU programming OpenCL language was used. Therefore the presented solution is fully portable.

  11. Comparative histomorphometric study of bone tissue synthesized after electric and ultrasound stimulation.

    PubMed

    Coman, Mălina; Hîncu, Mihaela; Surlin, Petra; Mateescu, Garofiţa; Nechita, A; Banu, Mihaela

    2011-01-01

    The clinical use of the alternative therapies in traumatology is conditioned by the knowledge and understanding of their actions on the bone tissue. The hereby study aims at the comparative assessment of the effectiveness of the direct current and ultrasounds in treating the fractures. Thus, we have proceeded to a comparative histological study of the bone tissue in the fractured area and the biomechanical description and the three-dimensional model of the stimulated bone's behavior by using micro-CT X-rays and the finite element analysis. The findings clearly show that the bone, which has been stimulated during a period of two weeks, has regained its functions, that is 85% of the compression one and 95% of the shearing one. These values prove that 90% of the bone structure has healed.

  12. Ultrasound and analysis of the deformation patterns of the masseter muscle: comparing surgical anatomy, ultrasound and functional anatomy

    PubMed Central

    BUSATO, A.; BALCONI, G.; VISMARA, V.; BERTELÈ, L.; GARO, G.; DE GREGORIO, D.

    2016-01-01

    SUMMARY Purpose We have tried to demonstrate whether the analysis of the muscle strain allows us to identify the three distinct functional areas of the architecture of the masseter, as one would see them by performing or viewing an anatomical dissection of said muscle, and whether these sections have behave differently in terms of origin and coping of the strain they face (quantitative analysis). Materials and methods This work has been elaborated by the use of an ultrasound machine (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5–12 MHz 40 mm) which allowed us to record a 45 frame per second video (DCM). Videos has been elaborated by use of an ultrasound machine (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5–12 MHz 40 mm) which allowed us to record a 45 frame per second video (DCM). We applied to the resulting video a software (Mudy 1.7.7.2 AMID Sulmona Italy) for the analysis of muscle deformation patters (contraction, dilatation, cross-plane, vertical strain, horizontal strain, vertical shear, horizontal shear, horizontal displacement, vertical displacement). The number of videos of masseter muscles in contraction at maximum exertion due to dental clenching made during this research is around 12,000. Out of these we chose 1,200 videos which examine 200 patients (100 females, 100 males). Results The deformation pattern analysis of the skeletal muscle on ultrasound basis seems to be an adequate instrument to use during the investigation of the functional structure of the masseter muscle given its ability to highlight the distinct activity of each separate part of the muscle. Conclusions Moreover the strain does not apply to the muscle uniformly; instead it varies according to the observed area. PMID:28280530

  13. Comparing efficiency of micro-RNA and mRNA biomarker liberation with microbubble-enhanced ultrasound exposure.

    PubMed

    Forbrich, Alex; Paproski, Robert; Hitt, Mary; Zemp, Roger

    2014-09-01

    Blood biomarkers are potentially powerful diagnostic tools that are limited clinically by low concentrations, the inability to determine biomarker origin and unknown patient baseline. Recently, ultrasound has been shown to liberate proteins and large mRNA biomarkers, overcoming many of these limitations. We have since demonstrated that adding lipid-stabilized microbubbles elevates mRNA concentration an order of magnitude compared with ultrasound without microbubbles, in vitro. Unfortunately the large size of some mRNA molecules may limit efficiency of release and hinder efficacy as an ultrasound-liberated biomarker. We hypothesize that smaller molecules will be released more efficiently with ultrasound than larger molecules. Although investigation of large libraries of biomarkers should be performed to fully validate this hypothesis, we focus on a small subset of mRNA and micro-RNAs. Specifically, we focus on miR-21 (22 base pairs [bp]), which is upregulated in certain forms of cancer, compared with previously investigated mammaglobin mRNA (502 bp). We also report release of micro-RNA miR-155 (22 bp) and housekeeping rRNA S18 (1869 bp). More than 10 million additional miR-21 copies per 100,000 cells are released with ultrasound-microbubble exposure. The low- molecular-weight miR-21 proved to be liberated 50 times more efficiently than high-molecular-weight mammaglobin mRNA, releasing orders of magnitude more miR-21 than mammaglobin mRNA under comparable conditions.

  14. Comparative study of ultrasound and computed tomography for incidentally detecting diffuse thyroid disease.

    PubMed

    Kim, Dong Wook; Jung, Soo Jin; Ha, Tae Kwun; Park, Ha Kyoung; Kang, Taewoo

    2014-08-01

    The aim of this study was to compare the diagnostic values of thyroid ultrasound (US) and neck computed tomography (CT) in incidentally detecting diffuse thyroid disease (DTD). A single radiologist made US and CT diagnoses of incidentally detected DTD in 130 consecutive patients before thyroidectomy for various malignancies. Histopathologic examinations confirmed normal thyroid (n = 80), Hashimoto thyroiditis (n = 20), non-Hashimoto lymphocytic thyroiditis (n = 28) and diffuse hyperplasia (n = 2). Receiver operating characteristic curves revealed that the best diagnostic indices of both imaging methods were achieved on the basis of two or more abnormal imaging findings. The sensitivity, specificity and accuracy of US and CT in incidentally detecting DTD by this classification were 72% and 72%, 87.5% and 91.3% and 81.5% and 83.8%, respectively. Thyroid US and neck CT have similar diagnostic values for differentiating incidental DTD from normal thyroid.

  15. Sensory and Quality Evaluation of Traditional Compared with Power Ultrasound Processed Corn (Zea Mays) Tortilla Chips.

    PubMed

    Janve, Bhaskar; Yang, Wade; Sims, Charles

    2015-06-01

    Power ultrasound reduces the traditional corn steeping time from 18 to 1.5 h during tortilla chips dough (masa) processing. This study sought to examine consumer (n = 99) acceptability and quality of tortilla chips made from the masa by traditional compared with ultrasonic methods. Overall appearance, flavor, and texture acceptability scores were evaluated using a 9-point hedonic scale. The baked chips (process intermediate) before and after frying (finished product) were analyzed using a texture analyzer and machine vision. The texture values were determined using the 3-point bend test using breaking force gradient (BFG), peak breaking force (PBF), and breaking distance (BD). The fracturing properties determined by the crisp fracture support rig using fracture force gradient (FFG), peak fracture force (PFF), and fracture distance (FD). The machine vision evaluated the total surface area, lightness (L), color difference (ΔE), Hue (°h), and Chroma (C*). The results were evaluated by analysis of variance and means were separated using Tukey's test. Machine vision values of L, °h, were higher (P < 0.05) and ΔE was lower (P < 0.05) for fried and L, °h were significantly (P < 0.05) higher for baked chips produced from ultra-sonication as compare to traditional. Baked chips texture for ultra-sonication was significantly higher (P < 0.05) on BFG, BPD, PFF, and FD. Fried tortilla chips texture were higher significantly (P < 0.05) in BFG and PFF for ultra-sonication than traditional processing. However, the instrumental differences were not detected in sensory analysis, concluding possibility of power ultrasound as potential tortilla chips processing aid.

  16. A Comparative Study of Fibroid Ablation Rates Using Radio Frequency or High-Intensity Focused Ultrasound

    SciTech Connect

    Meng Xin; He Guangbin; Zhang Jun; Han Zenghui; Yu Ming; Zhang Miaomiao; Tang Yu; Fang Ling; Zhou Xiaodong

    2010-08-15

    This study compared the technical success of fibroid devascularization using high-intensity focused ultrasound (HIFU) and radio frequency (RF) to provide an experimental basis for the clinical selection of a suitable, minimally invasive method for treating uterine fibroids. Patients were randomly divided into two groups and treated with HIFU or RF accordingly. The two groups of patients were divided again into subgroups A, B, and C based on fibroid diameter and subgroups A', B', and C' based on fibroid blood supply grades. The fibroid diameters in subgroups A, B, and C were 2.0 cm {<=} D < 4.0 cm, 4.0 cm {<=} D<6.0 cm and 6.0 cm {<=} D<8.0 cm, respectively, and fibroid blood supplies were classified into three grades corresponding to subgroups A', B', and C', respectively. The complete ablation rates of the two treatments were compared by contrast-enhanced ultrasound. Both treatments were effective, but the general complete ablation rate of RF was higher than that of HIFU (p < 0.05). The comparison between the two treatments in subgroup A and subgroup A' showed that the complete ablation rate of HIFU was as good as that of RF (p > 0.05). In other subgroups, the complete ablation rates of RF were better than those of HIFU (p < 0.05). No severe complications were observed after these two treatments. RF can be applied for the majority of fibroids. As a noninvasive therapy, HIFU could be the preferred method for the treatment of small, hypovascular fibroids.

  17. Duplex ultrasound and computed tomography angiography in the follow-up of endovascular abdominal aortic aneurysm repair: a comparative study*

    PubMed Central

    Cantador, Alex Aparecido; Siqueira, Daniel Emílio Dalledone; Jacobsen, Octavio Barcellos; Baracat, Jamal; Pereira, Ines Minniti Rodrigues; Menezes, Fábio Hüsemann; Guillaumon, Ana Terezinha

    2016-01-01

    Objective To compare duplex ultrasound and computed tomography (CT) angiography in terms of their performance in detecting endoleaks, as well as in determining the diameter of the aneurysm sac, in the postoperative follow-up of endovascular abdominal aortic aneurysm repair. Materials and Methods This was a prospective study involving 30 patients who had undergone endovascular repair of infrarenal aortoiliac aneurysms. Duplex ultrasound and CT angiography were performed simultaneously by independent radiologists. Measurements of the aneurysm sac diameter were assessed, and the presence or absence of endoleaks was determined. Results The average diameter of the aneurysm sac, as determined by duplex ultrasound and CT angiography was 6.09 ± 1.95 and 6.27 ± 2.16 cm, respectively. Pearson's correlation coefficient showing a statistically significant correlation (R = 0.88; p < 0.01). Comparing the duplex ultrasound and CT angiography results regarding the detection of endoleaks, we found that the former had a negative predictive value of 92.59% and a specificity of 96.15%. Conclusion Our results show that there is little variation between the two methods evaluated, and that the choice between the two would have no significant effect on clinical management. Duplex ultrasound could replace CT angiography in the postoperative follow-up of endovascular aneurysm repair of the infrarenal aorta, because it is a low-cost procedure without the potential clinical complications related to the use of iodinated contrast and exposure to radiation. PMID:27777476

  18. Reproducibility and accuracy of optic nerve sheath diameter assessment using ultrasound compared to magnetic resonance imaging

    PubMed Central

    2013-01-01

    Background Quantification of the optic nerve sheath diameter (ONSD) by transbulbar sonography is a promising non-invasive technique for the detection of altered intracranial pressure. In order to establish this method as follow-up tool in diseases with intracranial hyper- or hypotension scan-rescan reproducibility and accuracy need to be systematically investigated. Methods The right ONSD of 15 healthy volunteers (mean age 24.5 ± 0.8 years) were measured by both transbulbar sonography (9 – 3 MHz) and 3 Tesla MRI (half-Fourier acquisition single-shot turbo spin-echo sequences, HASTE) 3 and 5 mm behind papilla. All volunteers underwent repeated ultrasound and MRI examinations in order to assess scan-rescan reproducibility and accuracy. Moreover, inter- and intra-observer variabilities were calculated for both techniques. Results Scan-rescan reproducibility was robust for ONSD quantification by sonography and MRI at both depths (r > 0.75, p ≤ 0.001, mean differences < 2%). Comparing ultrasound- and MRI-derived ONSD values, we found acceptable agreement between both methods for measurements at a depth of 3 mm (r = 0.72, p = 0.002, mean difference < 5%). Further analyses revealed good inter- and intra-observer reliability for sonographic measurements 3 mm behind the papilla and for MRI at 3 and 5 mm (r > 0.82, p < 0.001, mean differences < 5%). Conclusions Sonographic ONSD quantification 3 mm behind the papilla can be performed with good reproducibility, measurement accuracy and observer agreement. Thus, our findings emphasize the feasibility of this technique as a non-invasive bedside tool for longitudinal ONSD measurements. PMID:24289136

  19. Duplex ultrasound

    MedlinePlus

    Vascular ultrasound; Peripheral vascular ultrasound ... A duplex ultrasound combines: Traditional ultrasound: This uses sound waves that bounce off blood vessels to create pictures. Doppler ultrasound: This ...

  20. A comparative evaluation of three hydrophones and a numerical model in high intensity focused ultrasound fields.

    PubMed

    Haller, Julian; Jenderka, Klaus-Vitold; Durando, Gianni; Shaw, Adam

    2012-02-01

    The pressure fields of two different high intensity focused ultrasound (HIFU) transducers operated in burst mode were measured at acoustical power levels of 25 and 50 W (continuous wave equivalent) with three different hydrophones: A fiber-optic displacement sensor, a commercial HIFU needle hydrophone, and a prototype of a membrane hydrophone with a protective coating against cavitation effects. Additionally, the fields were modeled using a freely available simulations software package. The measured waveforms, the peak pressure profiles, as well as the spatial-peak temporal-average intensities from the different devices and from the modeling are compared and possible reasons for differences are discussed. The results clearly show that reliable pressure measurements in HIFU fields remain a difficult task concerning both the reliability of the measured values and the robustness of the sensors used: Only the fiber-optic hydrophone survived all four exposure regimes and the measured spatial-peak temporal-average intensities varied by a factor of up to 1.5 between the measurements and the modeling and between the measurements among themselves.

  1. Critical assessment of intramodality 3D ultrasound imaging for prostate IGRT compared to fiducial markers

    SciTech Connect

    Meer, Skadi van der; Bloemen-van Gurp, Esther; Hermans, Jolanda; Voncken, Robert; Heuvelmans, Denys; Gubbels, Carol; Fontanarosa, Davide; Visser, Peter; Lutgens, Ludy; Gils, Francis van; Verhaegen, Frank

    2013-07-15

    Purpose: A quantitative 3D intramodality ultrasound (US) imaging system was verified for daily in-room prostate localization, and compared to prostate localization based on implanted fiducial markers (FMs).Methods: Thirteen prostate patients underwent multiple US scans during treatment. A total of 376 US-scans and 817 matches were used to determine the intra- and interoperator variability. Additionally, eight other patients underwent daily prostate localization using both US and electronic portal imaging (EPI) with FMs resulting in 244 combined US-EPI scans. Scanning was performed with minimal probe pressure and a correction for the speed of sound aberration was performed. Uncertainties of both US and FM methods were assessed. User variability of the US method was assessed.Results: The overall US user variability is 2.6 mm. The mean differences between US and FM are: 2.5 {+-} 4.0 mm (LR), 0.6 {+-} 4.9 mm (SI), and -2.3 {+-} 3.6 mm (AP). The intramodality character of this US system mitigates potential errors due to transducer pressure and speed of sound aberrations.Conclusions: The overall accuracy of US (3.0 mm) is comparable to our FM workflow (2.2 mm). Since neither US nor FM can be considered a gold standard no conclusions can be drawn on the superiority of either method. Because US imaging captures the prostate itself instead of surrogates no invasive procedure is required. It requires more effort to standardize US imaging than FM detection. Since US imaging does not involve a radiation burden, US prostate imaging offers an alternative for FM EPI positioning.

  2. Comparable Outcomes of Ultrasound versus Computed Tomography in the Guidance of Radiofrequency Ablation for Hepatocellular Carcinoma

    PubMed Central

    Lee, Lu-Hung; Hwang, Jen-I; Cheng, Yu-Chi; Wu, Chun-Ying; Lee, Shou-Wu; Yang, Sheng-Shun; Yeh, Hong-Zen; Chang, Chi-Sen; Lee, Teng-Yu

    2017-01-01

    Objectives To compare the efficacy and safety of ultrasound (US) and computed tomography (CT) in the guidance of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Materials and Methods We retrospectively analyzed consecutive treatment-naïve patients who received curative RFA for HCC from January 2008 to July 2013. Patients were divided into the US group or the CT group according to their RFA guidance instruments. Patients who were only suitable for US- or CT-guided RFA were excluded. Cumulative incidences of and hazard ratios for HCC recurrence were analyzed after adjusting for competing mortality risk. Results We recruited a total of 101 patients in the US group and 51 patients in the CT group. The baseline demographic characteristics were not significantly different in both groups. Initial response rates were similar between the two groups (US vs. CT: 89.1% vs. 92.2%, p = 0.54), and complete tumor ablation was finally achieved for all patients. However, more ablations per session were performed in US group (median 2.0 [1.0–3.0] vs. 1.0 [1.0–2.0]; p<0.01). The 1-, 2- and 3-year local tumor recurrence rates (US vs. CT: 13.0%, 20.9%, and 29.2% vs. 11.2%, 29.8% and 29.8%, respectively) and overall mortality rates (US vs. CT: 5.2%, 9.6% and 16.5% vs. 0%, 3.1% and 23.8%, respectively) were not significantly different. In multivariate analysis, tumor characteristics and underlying liver function, but not US or CT guidance, were independent prognostic factors. The complication rates were similar between the two groups (US vs. CT: 10.9% vs. 9.8%; p = 0.71), and there was no procedure-related mortality. Conclusions With comparable major outcomes, either US or CT can be used in the guidance of RFA in experience hands. PMID:28068369

  3. Is ultrasound of bone relevant for corticosteroid-treated patients? A comparative study with bone densitometry measured by DEXA.

    PubMed

    Oliveri, Beatriz; Di Gregorio, Silvana; Parisi, Muriel Solange; Solís, Fabiana; Mautalen, Carlos

    2003-02-01

    Corticosteroid treatment diminishes bone mass and alters bone quality. The objective was to evaluate bone in corticosteroid-treated patients and controls and in fractured and non-fractured patients treated with corticosteroids using both X-ray densitometry (DEXA) and ultrasound. We evaluated 34 women aged 58 +/- 14 years (X +/- SD), who had been on long-term low dose prednisone therapy for at least 6 months, and who had never received specific treatment for osteoporosis. Bone mineral density of total skeleton (TS), lumbar spine (LS), femoral neck (FN), and vertebral morphometry (MXA) were measured by DEXA. Speed of sound (SOS), broadband ultrasound attenuation (BUA) and stiffness were measured using an Achilles Plus system. Forty-two healthy women served as controls. Both densitometric and ultrasound parameters in the patients were significantly diminished compared with controls: TS: P < 0.002, LS: P < 0.025, FS: P < 0.005, Stiffness: P < 0.001, BUA: P < 0.002 and SOS: P < 0.002. The percentage of patients with a Z score below -2 was higher in Stiffness and BUA: 38% and 47%, respectively, compared with a range of 16-24% in the other parameters (P < 0.05 BUA vs. DEXA measurements). Eleven patients with previous bone fracture had values lower than the non-fractured patients, both according to DEXA and ultrasound measurements, but the difference was only significant for BUA (P < 0.02). BUA of the calcaneus was more effective in detecting the specific skeletal alterations and fracture risk of the group of patients receiving chronic corticosteroid treatment.

  4. Automatic Cataract Classification based on Ultrasound Technique Using Machine Learning: A comparative Study

    NASA Astrophysics Data System (ADS)

    Caxinha, Miguel; Velte, Elena; Santos, Mário; Perdigão, Fernando; Amaro, João; Gomes, Marco; Santos, Jaime

    This paper addresses the use of computer-aided diagnosis (CAD) system for the cataract classification based on ultrasound technique. Ultrasound A-scan signals were acquired in 220 porcine lenses. B-mode and Nakagami images were constructed. Ninety-seven parameters were extracted from acoustical, spectral and image textural analyses and were subjected to feature selection by Principal Component Analysis (PCA). Bayes, K Nearest-Neighbors (KNN), Fisher Linear Discriminant (FLD) and Support Vector Machine (SVM) classifiers were tested. The classification of healthy and cataractous lenses shows a good performance for the four classifiers (F-measure ≥92.68%) with SVM showing the highest performance (90.62%) for initial versus severe cataract classification.

  5. A Comparative Analysis of Ultrasound Velocity in Binary Liquid Systems of PPG by Mathematical and Experimental Methods

    NASA Astrophysics Data System (ADS)

    Gayathri, A.; Venugopal, T.; Venkatramanan, K.

    The estimation of the speed of ultrasound is the fundamental requirement for investigating the transport properties of liquid and solid systems. Ultrasonic velocities of liquid mixtures containing polar and non-polar groups are of considerable importance in understanding inter-molecular interaction between component molecules and they find applications in several industrial and technological processes. There are many standard mathematical methods available to measure the ultrasonic velocity. In the present study, interferometric technique is planned for experimental measurement of ultrasound velocity. In this paper, the speed of ultrasound waves in Polypropylene Glycol (PPG 400, PPG 4000) in toluene has been estimated for different concentrations (2%, 4%, 6%, 8% & 10%) at 303K and these experimental values compared with theoretical values obtained by using various mathematical methods like Nomotto's Relation, Vandeal Vangeal Relation, Impedance Relation, and Rao's specific sound velocity. The most reliable method that matches with experimental method is identified using Average Percentage Error (APE) and analysed in the light of molecular interactions occurring in the binary liquid systems. Comparison of evaluated theoretical velocities with experimental values will reveal the nature of interaction between component molecules in the mixtures. Such theoretical study is useful in defining a comprehensive theoretical model for a specific liquid mixture. Also, various molecular interaction parameters like free volume, internal pressure, viscous relaxation time, inter atomic free length, etc are calculated and discussed in terms of polymer-solvent interactions.

  6. Investigation of foreign objects in soft-tissue using a PE-CMOS ultrasound system: a preliminary comparative study

    NASA Astrophysics Data System (ADS)

    Liu, Chu-Chuan; Lo, Shih-Chung Ben; Freedman, Matthew T.; Lasser, Marvin E.; Lasser, Bob; Kula, John; Wang, Yue Joseph; Hsieh, Tsung-I.; Sarcone, Anita

    2006-03-01

    In this study, we have tested the ability of four imaging modalities to investigate foreign objects in soft tissue. We inserted wood, plastic, glass, and aluminum objects into a pork sample to simulate traumatized soft tissue. Each object was inserted into the skin, then passed through the fat tissue layer and penetrated into the muscle layer. We then took images of the pork sample using four different modalities: (1) a C-Scan imaging prototype which consists of an unfocused transducer, a compound acoustic lens, and a 2D ultrasound sensor array based on the piezoelectric sensing complementary metal-oxide semiconductor (PE-CMOS) technology; (2) a portable B-Scan ultrasound system; (3) a conventional X-ray system; (4) and a computed radiography (CR) X-ray system. We found that the aluminum and glass objects were clearly visible in both conventional X-ray and CR X-ray images with good contrast-to-noise ratio (CNR); however, the wood and plastic objects could not be clearly seen using these modalities. However, we found that the wood, plastic, and glass objects, as well as the thicker aluminum object, were clearly visible in the C-Scan ultrasound images. Furthermore, the fold fibro structures of the fat and muscle tissues in the pork were observable using this modality. The C-Scan prototype images produce neither speckle nor geometry distortion. Both of these issues are commonly seen in B-Scan ultrasound. The results of this study also indicate that the C-Scan images have better CNRs for most foreign objects when compared to other imaging modalities.

  7. Note: Comparative experimental studies on the performance of 2-2 piezocomposite for medical ultrasound transducers

    NASA Astrophysics Data System (ADS)

    Marinozzi, F.; Bini, F.; Biagioni, A.; Grandoni, A.; Spicci, L.

    2013-09-01

    The paper reports the experimental investigation of the behavior of 2-2 Lead Zirconate Titanate (PZT)-polymer composite transducers array for clinical ultrasound equipments. Several 2-2 plate composites having the same dicing pitch of 0.11 mm and different volume fractions were manufactured and investigated. Measurements were performed through different techniques such as electrical impedance, pulse-echo, and Laser Doppler Vibrometer. With the last one, maps of the surface displacement were presented relative to thickness mode and first lateral mode resonance frequencies. The transducers with volume fractions of the 40% resulted markedly inefficient, whereas the largest bandwidth and best band shape were achieved by the 50%.

  8. A randomized, double-blind clinical trial comparing the effects of continuous and pulsed ultrasound in patients with chronic rhinosinusitis.

    PubMed

    Ansari, Noureddin Nakhostin; Fathali, Mojtaba; Naghdi, Soofia; Hasson, Scott; Jalaie, Shohreh; Rastak, Mohammad Saeed

    2012-02-01

    The objective of the present study was to compare the effects of continuous ultrasound (CUS) with pulsed ultrasound (PUS) in patients with chronic rhinosinusitis (CRS). In this prospective, randomized, double-blind, parallel group study, 40 patients (10 losses) with CRS participated. Patients received either continuous or pulsed (1:9) 1 MHz ultrasound (US) using a US head of 1 cm2 at 1 W/cm2 and 0.5 W/cm2 for the maxillary and frontal sinuses, respectively. Treatment was performed in 10 sessions, 3 days per week, with US given every other day. The primary outcome measure was percent improvement in the Sinusitis Symptom Score. Measurements were taken before and after 10 treatment sessions. The patients were followed up monthly for 2 months. After treatment, both groups improved significantly on the Sinusitis Symptoms Score. Patients who received PUS had significantly decreased total symptom scores compared with patients receiving CUS (mean change 9.8 vs. 5.6, p = 0.049). The percent improvement in the Sinusitis Symptom Score between the PUS group (65.2 SD 23.1) and the CUS group (43.9 SD 40.7) was not statistically significant (p = 0.09). The effect size for each treatment was large; PUS: d = 3.92 and CUS: d = 1.93. Symptom improvement in both groups was similar at the 2-month follow-up. These results support the use of therapeutic US for CRS. This pilot study gives only marginal evidence to favor PUS over CUS.

  9. [Comparative study of the efficacy of ultrasound and sonophoresis in the treatment of painful shouder syndrome].

    PubMed

    Vlak, T

    1999-01-01

    This research tries to determine the difference between two forms of physical therapy, as regards their efficiency, in treating painful shoulder syndrome. They are ultrasound and sonophoresis. The research comprised 64 patients, divided in two groups. One group was treated by 10 ultrasound procedures (16 women and 17 men, average age 49.3 years), the other by 10 sonophoresis (14 women and 17 men, average age 45.1 years), both having in addition individual physical training (corrective medical exercises) for each patient. The difference in efficiency regarding both procedures were observed on the basis of objective measurable parameters (abduction, anteflexion, retroflexion, outer and inner rotation, the distance between vertebrae prominens and styloid radius) as well as in view of anamnestic terms (pain both at rest and in motion) recorded before the treatment started and after the application of 10 therapeutic procedures. The statistics results of data processing showed significant difference in efficiency, regarding the objective parameters--sonophoresis is more efficient (retroflexion--p < 0.05). Nevertheless, sonophoresis (diclofenac gel) proved much more efficient in reducing pain at rest (p < 0.01) and in motion (p < 0.05).

  10. Ultrasound detection of visceral adhesion after intraperitoneal ventral hernia treatment: a comparative study of protected versus unprotected meshes.

    PubMed

    Arnaud, J P; Hennekinne-Mucci, S; Pessaux, P; Tuech, J J; Aube, C

    2003-06-01

    Intraperitoneal (IP) ventral hernia repair has been proposed with the advantages of reducing dissection, operative time, and postoperative pain. The IP position of the mesh is suspected of increasing the risk of visceral adhesion and inducing complications. To overcome these drawbacks, a mesh protected on one side by a hydrophilic resorbable film (Parietex Composite) has been validated. Using a previously described ultrasound procedure, the purpose of this study was to compare the rate of visceral adhesion after intraperitoneal placement of a polyester mesh versus this protected mesh. Fifty-one patients who received a Parietex Composite mesh were prospectively compared to a retrospective series of 22 consecutive asymptomatic patients who received a Mersilene mesh. To objectively assess visceral adhesion toward the abdominal wall, an ultrasound (US) specific examination was firstly validated and secondly used to evaluate the adhesion incidence in both groups. Both groups were equivalent in terms of inclusion criteria and body mass index (BMI). Pre-operative US versus perioperative macroscopical findings determined the following parameters: sensitivity 83%, accuracy 78%, negative predictive value 81%. Using this procedure, 77% of the patients exhibited visceral adhesion to the mesh in the Mersilene group, against 18% in the Parietex Composite group (P<0.001, chi-square). US examination represents a suitable tool to evaluate postoperative adhesions to the abdominal wall. Using this procedure, a significant reduction of visceral adhesion in the Parietex Composite group was shown.

  11. Prostate volume estimations using magnetic resonance imaging and transrectal ultrasound compared to radical prostatectomy specimens

    PubMed Central

    Paterson, Nicholas R.; Lavallée, Luke T.; Nguyen, Laura N.; Witiuk, Kelsey; Ross, James; Mallick, Ranjeeta; Shabana, Wael; MacDonald, Blair; Scheida, Nicola; Fergusson, Dean; Momoli, Franco; Cnossen, Sonya; Morash, Christopher; Cagiannos, Ilias; Breau, Rodney H.

    2016-01-01

    Introduction: We sought to evaluate the accuracy of prostate volume estimates in patients who received both a preoperative transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) in relation to the referent pathological specimen post-radical prostatectomy. Methods: Patients receiving both TRUS and MRI prior to radical prostatectomy at one academic institution were retrospectively analyzed. TRUS and MRI volumes were estimated using the prolate ellipsoid formula. TRUS volumes were collected from sonography reports. MRI volumes were estimated by two blinded raters and the mean of the two was used for analyses. Pathological volume was calculated using a standard fluid displacement method. Results: Three hundred and eighteen (318) patients were included in the analysis. MRI was slightly more accurate than TRUS based on interclass correlation (0.83 vs. 0.74) and absolute risk bias (higher proportion of estimates within 5, 10, and 20 cc of pathological volume). For TRUS, 87 of 298 (29.2%) prostates without median lobes differed by >10 cc of specimen volume and 22 of 298 (7.4%) differed by >20 cc. For MRI, 68 of 298 (22.8%) prostates without median lobes differed by >10 cc of specimen volume, while only 4 of 298 (1.3%) differed by >20 cc. Conclusions: MRI and TRUS prostate volume estimates are consistent with pathological volumes along the prostate size spectrum. MRI demonstrated better correlation with prostatectomy specimen volume in most patients and may be better suited in cases where TRUS and MRI estimates are disparate. Validation of these findings with prospective, standardized ultrasound techniques would be helpful. PMID:27878049

  12. Shear Wave Elastography May Add a New Dimension to Ultrasound Evaluation of Thyroid Nodules: Case Series with Comparative Evaluation

    PubMed Central

    Slapa, Rafal Z.; Piwowonski, Antoni; Jakubowski, Wieslaw S.; Bierca, Jacek; Szopinski, Kazimierz T.; Slowinska-Srzednicka, Jadwiga; Migda, Bartosz; Mlosek, R. Krzysztof

    2012-01-01

    Although elastography can enhance the differential diagnosis of thyroid nodules, its diagnostic performance is not ideal at present. Further improvements in the technique and creation of robust diagnostic criteria are necessary. The purpose of this study was to compare the usefulness of strain elastography and a new generation of elasticity imaging called supersonic shear wave elastography (SSWE) in differential evaluation of thyroid nodules. Six thyroid nodules in 4 patients were studied. SSWE yielded 1 true-positive and 5 true-negative results. Strain elastography yielded 5 false-positive results and 1 false-negative result. A novel finding appreciated with SSWE, were punctate foci of increased stiffness corresponding to microcalcifications in 4 nodules, some not visible on B-mode ultrasound, as opposed to soft, colloid-inspissated areas visible on B-mode ultrasound in 2 nodules. This preliminary paper indicates that SSWE may outperform strain elastography in differentiation of thyroid nodules with regard to their stiffness. SSWE showed the possibility of differentiation of high echogenic foci into microcalcifications and inspissated colloid, adding a new dimension to thyroid elastography. Further multicenter large-scale studies of thyroid nodules evaluating different elastographic methods are warranted. PMID:22685685

  13. A Comparative Study on the Influence of Probe Placement on Quality Assurance Measurements in B-mode Ultrasound by Means of Ultrasound Phantoms

    PubMed Central

    Scorza, A; Conforto, S; D'Anna, C; Sciuto, S.A

    2015-01-01

    To check or to prevent failures in ultrasound medical systems, some tests should be scheduled for both clinical suitability and technical functionality evaluation: among them, image quality assurance tests performed by technicians through ultrasound phantoms are widespread today and their results depend on issues related to scanner settings as well as phantom features and operator experience. In the present study variations on some features of the B-mode image were measured when the ultrasound probe is handled by the technician in a routine image quality test: ultrasound phantom images from two array transducers are processed to evaluate measurement dispersion in distance accuracy, high contrast spatial resolution and penetration depth when probe is handled by the operator. All measurements are done by means of an in-house image analysis software that minimizes errors due to operator’s visual acuity and subjective judgment while influences of ultrasound transducer position on quality assurance test results are estimated as expanded uncertainties on parameters above (measurement reproducibility at 95 percent confidence level): depending on the probe model, they ranged from ±0.1 to ±1.9 mm in high contrast spatial resolution, from ±0.1 to ±5.5 percent in distance measurements error and from ±1 to ±10 mm in maximum depth of signal visualization. Although numerical results are limited to the two examined probes, they confirm some predictions based on general working principles of diagnostic ultrasound systems: (a) measurements strongly depend on settings as well on phantoms features, probes and parameters investigated; (b) relative uncertainty due to probe manipulation on spatial resolution can be very high, i.e. from 10 to more than 30 percent; (c) Field of View settings must be taken into account for measurement reproducibility as well as Dynamic Range compression and phantom attenuation. PMID:26312078

  14. Are Ultrasound-Guided Ophthalmic Blocks Injurious to the Eye? A Comparative Rabbit Model Study of Two Ultrasound Devices Evaluating Intraorbital Thermal and Structural Changes

    PubMed Central

    Palte, Howard D.; Gayer, Steven; Arrieta, Esdras; Shaw, Eric Scot; Nose, Izuru; Lee, Elizabete; Arheart, Kristopher L.; Dubovy, Sander; Birnbach, David J.; Parel, Jean-Marie

    2012-01-01

    Background Since Atkinson’s original description of retrobulbar block in 1936, needle-based anesthetic techniques have become integral to ophthalmic anesthesia. These techniques are unfortunately associated with rare, grave complications such as globe perforation. Ultrasound has gained widespread acceptance for peripheral nerve blockade but its translation to ocular anesthesia has been hampered because sonic energy, in the guise of thermal or biomechanical insult, is potentially injurious to vulnerable eye tissue. The United States Food and Drug Administration have defined guidelines for safe use of ultrasound for ophthalmic examination but most ultrasound devices used by anesthesiologists are not Food and Drug Administration-approved for ocular application because they generate excessive energy. Regulating agencies state that ultrasound examination can be safely undertaken as long as tissue temperatures do not increase >1.5°C above physiological levels. Methods Using a rabbit model, we investigated the thermal and mechanical ocular effects after prolonged ultrasonic exposure to single orbital and non-orbital-rated devices. In a dual-phase study, aimed at detecting ocular injury, the eyes of 8 rabbits were exposed to continuous 10-minute ultrasound examinations from two devices: 1) the Sonosite Micromaxx (non-orbital-rated) and 2) the Sonomed VuMax (orbital-rated) machines. In Phase I temperatures were continuously monitored via thermocouples implanted within specific eye structures (n=4). In Phase II the eyes were subjected to ultrasonic exposure without surgical intervention (n=4). All eyes underwent light microscopy examinations followed, at different intervals, by histology evaluations conducted by an ophthalmic pathologist. Results Temperature changes were monitored in the eyes of four rabbits. The non-orbital-rated transducer produced increases in ocular tissue temperature that surpassed the safe limit (increases> 1.50C ) in the lens of three rabbits (at 5

  15. [Comparative evaluation of bone mineral density in Mexican women using x-ray bone densitometry and ultrasound].

    PubMed

    Llaca Rodríguez, V; Aguilera Pérez, R; Ahued Ahued, R; Rio de la Loza, F; Mendoza Torres, L J; Coria Soto, I; Zambrana Castañeda, M M

    2000-03-01

    With lifestyle changes in women, smoking and use of beverages with caffeine, and sedentarism increasing, so the risk factors for decalcification, increase; which is a public health problem by the higher incidence of osteoporotic fractures, as the age advances, specially in the postmenopause woman, which means a greater secondary morbidity-mortality; an important cause of physical disability, which directly affects psychoemotional wellbeing in women. In this study two methods of bone densitometry, were used; one of x ray, and other with ultrasound in 138 women during postmenopause with an average index of corporal mass of 29. Both results were compared of bone density, T measurement with osteopenia and osteoporosis. Double densitometry, was done in the 138 patients of lumbar spine with DEXA equipment, and of calcaneum with DTU-one equipment, by the same technician, finding the difference of T punctuation in this double study.

  16. Comparative imaging study in ultrasound, MRI, CT, and DSA using a multimodality renal artery phantom

    SciTech Connect

    King, Deirdre M.; Fagan, Andrew J.; Moran, Carmel M.; Browne, Jacinta E.

    2011-02-15

    Purpose: A range of anatomically realistic multimodality renal artery phantoms consisting of vessels with varying degrees of stenosis was developed and evaluated using four imaging techniques currently used to detect renal artery stenosis (RAS). The spatial resolution required to visualize vascular geometry and the velocity detection performance required to adequately characterize blood flow in patients suffering from RAS are currently ill-defined, with the result that no one imaging modality has emerged as a gold standard technique for screening for this disease. Methods: The phantoms, which contained a range of stenosis values (0%, 30%, 50%, 70%, and 85%), were designed for use with ultrasound, magnetic resonance imaging, x-ray computed tomography, and x-ray digital subtraction angiography. The construction materials used were optimized with respect to their ultrasonic speed of sound and attenuation coefficient, MR relaxometry (T{sub 1},T{sub 2}) properties, and Hounsfield number/x-ray attenuation coefficient, with a design capable of tolerating high-pressure pulsatile flow. Fiducial targets, incorporated into the phantoms to allow for registration of images among modalities, were chosen to minimize geometric distortions. Results: High quality distortion-free images of the phantoms with good contrast between vessel lumen, fiducial markers, and background tissue to visualize all stenoses were obtained with each modality. Quantitative assessments of the grade of stenosis revealed significant discrepancies between modalities, with each underestimating the stenosis severity for the higher-stenosed phantoms (70% and 85%) by up to 14%, with the greatest discrepancy attributable to DSA. Conclusions: The design and construction of a range of anatomically realistic renal artery phantoms containing varying degrees of stenosis is described. Images obtained using the main four diagnostic techniques used to detect RAS were free from artifacts and exhibited adequate contrast

  17. Abdominal Ultrasound

    MedlinePlus

    ... Ultrasound - Abdomen Ultrasound imaging of the abdomen uses sound waves to produce pictures of the structures within ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  18. Hip Ultrasound

    MedlinePlus

    ... Index A-Z Hip Ultrasound Hip ultrasound uses sound waves to produce pictures of muscles, tendons, ligaments, ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  19. Obstetrical Ultrasound

    MedlinePlus

    ... Index A-Z Obstetric Ultrasound Obstetric ultrasound uses sound waves to produce pictures of a baby (embryo ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  20. Computer-aided diagnosis of Myocardial Infarction using ultrasound images with DWT, GLCM and HOS methods: A comparative study.

    PubMed

    Vidya, K Sudarshan; Ng, E Y K; Acharya, U Rajendra; Chou, Siaw Meng; Tan, Ru San; Ghista, Dhanjoo N

    2015-07-01

    Myocardial Infarction (MI) or acute MI (AMI) is one of the leading causes of death worldwide. Precise and timely identification of MI and extent of muscle damage helps in early treatment and reduction in the time taken for further tests. MI diagnosis using 2D echocardiography is prone to inter-/intra-observer variability in the assessment. Therefore, a computerised scheme based on image processing and artificial intelligent techniques can reduce the workload of clinicians and improve the diagnosis accuracy. A Computer-Aided Diagnosis (CAD) of infarcted and normal ultrasound images will be useful for clinicians. In this study, the performance of CAD approach using Discrete Wavelet Transform (DWT), second order statistics calculated from Gray-Level Co-Occurrence Matrix (GLCM) and Higher-Order Spectra (HOS) texture descriptors are compared. The proposed system is validated using 400 MI and 400 normal ultrasound images, obtained from 80 patients with MI and 80 normal subjects. The extracted features are ranked based on t-value and fed to the Support Vector Machine (SVM) classifier to obtain the best performance using minimum number of features. The features extracted from DWT coefficients obtained an accuracy of 99.5%, sensitivity of 99.75% and specificity of 99.25%; GLCM have achieved an accuracy of 85.75%, sensitivity of 90.25% and specificity of 81.25%; and HOS obtained an accuracy of 93.0%, sensitivity of 94.75% and specificity of 91.25%. Among the three techniques presented DWT yielded the highest classification accuracy. Thus, the proposed CAD approach may be used as a complementary tool to assist cardiologists in making a more accurate diagnosis for the presence of MI.

  1. Evaluation of cost-effectiveness from the funding body's point of view of ultrasound-guided central venous catheter insertion compared with the conventional technique

    PubMed Central

    Noritomi, Danilo Teixeira; Zigaib, Rogério; Ranzani, Otavio T.; Teich, Vanessa

    2016-01-01

    Objective To evaluate the cost-effectiveness, from the funding body's point of view, of real-time ultrasound-guided central venous catheter insertion compared to the traditional method, which is based on the external anatomical landmark technique. Methods A theoretical simulation based on international literature data was applied to the Brazilian context, i.e., the Unified Health System (Sistema Único de Saúde - SUS). A decision tree was constructed that showed the two central venous catheter insertion techniques: real-time ultrasonography versus external anatomical landmarks. The probabilities of failure and complications were extracted from a search on the PubMed and Embase databases, and values associated with the procedure and with complications were taken from market research and the Department of Information Technology of the Unified Health System (DATASUS). Each central venous catheter insertion alternative had a cost that could be calculated by following each of the possible paths on the decision tree. The incremental cost-effectiveness ratio was calculated by dividing the mean incremental cost of real-time ultrasound compared to the external anatomical landmark technique by the mean incremental benefit, in terms of avoided complications. Results When considering the incorporation of real-time ultrasound and the concomitant lower cost due to the reduced number of complications, the decision tree revealed a final mean cost for the external anatomical landmark technique of 262.27 Brazilian reals (R$) and for real-time ultrasound of R$187.94. The final incremental cost of the real-time ultrasound-guided technique was -R$74.33 per central venous catheter. The incremental cost-effectiveness ratio was -R$2,494.34 due to the pneumothorax avoided. Conclusion Real-time ultrasound-guided central venous catheter insertion was associated with decreased failure and complication rates and hypothetically reduced costs from the view of the funding body, which in this

  2. Comparative assessments of the effects of alcohol exposure on fetal brain development using optical coherence tomography and ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Sudheendran, Narendran; Bake, Shameena; Miranda, Rajesh C.; Larin, Kirill V.

    2013-02-01

    The developing fetal brain is vulnerable to a variety of environmental agents including maternal ethanol consumption. Preclinical studies on the development and amelioration of fetal teratology would be significantly facilitated by the application of high resolution imaging technologies like optical coherence tomography (OCT) and high-frequency ultrasound (US). This study investigates the ability of these imaging technologies to measure the effects of maternal ethanol exposure on brain development, ex vivo, in fetal mice. Pregnant mice at gestational day 12.5 were administered ethanol (3 g/Kg b.wt.) or water by intragastric gavage, twice daily for three consecutive days. On gestational day 14.5, fetuses were collected and imaged. Three-dimensional images of the mice fetus brains were obtained by OCT and high-resolution US, and the volumes of the left and right ventricles of the brain were measured. Ethanol-exposed fetuses exhibited a statistically significant, 2-fold increase in average left and right ventricular volumes compared with the ventricular volume of control fetuses, with OCT-derived measures of 0.38 and 0.18 mm3, respectively, whereas the boundaries of the fetal mouse lateral ventricles were not clearly definable with US imaging. Our results indicate that OCT is a useful technology for assessing ventriculomegaly accompanying alcohol-induced developmental delay. This study clearly demonstrated advantages of using OCT for quantitative assessment of embryonic development compared with US imaging.

  3. Comparing a volume based template approach and ultrasound guided freehand approach in multicatheter interstitial accelerated partial breast irradiation

    PubMed Central

    Koh, Vicky Y.; Buhari, Shaik A.; Tan, Poh Wee; Tan, Yun Inn; Leong, Yuh Fun; Earnest, Arul

    2014-01-01

    Purpose Currently, there are two described methods of catheter insertion for women undergoing multicatheter interstitial accelerated partial breast irradiation (APBI). These are a volume based template approach (template) and a non-template ultrasound guidance freehand approach (non-template). We aim to compare dosimetric endpoints between the template and non-template approach. Material and methods Twenty patients, who received adjuvant multicatheter interstitial APBI between August 2008 to March 2010 formed the study cohort. Dosimetric planning was based on the RTOG 04-13 protocol. For standardization, the planning target volume evaluation (PTV-Eval) and organs at risk were contoured with the assistance of the attending surgeon. Dosimetric endpoints include D90 of the PTV-Eval, Dose Homogeneity Index (DHI), V200, maximum skin dose (MSD), and maximum chest wall dose (MCD). A median of 18 catheters was used per patient. The dose prescribed was 34 Gy in 10 fractions BID over 5 days. Results The average breast volume was 846 cm3 (526-1384) for the entire cohort and there was no difference between the two groups (p = 0.6). Insertion time was significantly longer for the non-template approach (mean 150 minutes) compared to the template approach (mean: 90 minutes) (p = 0.02). The planning time was also significantly longer for the non-template approach (mean: 240 minutes) compared to the template approach (mean: 150 minutes) (p < 0.01). The template approach yielded a higher D90 (mean: 95%) compared to the non-template approach (mean: 92%) (p < 0.01). There were no differences in DHI (p = 0.14), V200 (p = 0.21), MSD (p = 0.7), and MCD (p = 0.8). Conclusions Compared to the non-template approach, the template approach offered significant shorter insertion and planning times with significantly improved dosimetric PTV-Eval coverage without significantly compromising organs at risk dosimetrically. PMID:25097558

  4. Management of myofascial pain by therapeutic ultrasound and transcutaneous electrical nerve stimulation: A comparative study

    PubMed Central

    Rai, Shalu; Ranjan, Vikash; Misra, Deepankar; Panjwani, Sapna

    2016-01-01

    Objective: The present comparative study was aimed to determine the effectiveness of Th US and TENS in the management of myofascial pain in TMD patients. Materials and Methods: The present randomized comparative study was on 90 patients who were further assigned in three different groups each having 30 patients; Group I was healthy control patients, Group II was receiving Th US therapy, and Group III was receiving TENS therapy. All the 90 patients were further evaluated for maximum inter incisor subjective evaluation regarding muscle pain, impediment to daily life, massage impression on visual analog scale (VAS) scale, and intensity and duration used in Th US massage. Results: The masseter muscle thickness in control group was 12.00 (standard deviation [SD] ±1.1) mm when compared with TMD patient of 13.00 (SD ± 1.1) mm before treatment. Statistical significant findings on VAS score of muscle pain, impediment to daily life, and massage impression were observed in Th US. After treatment, the anechoic areas disappeared or were reduced in Th US group by 95.6% and in TENS by 74.4%. Conclusion: Th US appeared to be subjectively better which was related to VAS score of massage impression, muscle pain, and impediment to daily life after treatment as well as sonographically related to existence of anechoic areas. PMID:27011739

  5. Lab-on-fiber platforms for ultrasound detection: a comparative study

    NASA Astrophysics Data System (ADS)

    Giaquinto, M.; Ricciardi, A.; Cutolo, A.; Cusano, A.

    2015-09-01

    Sub-wavelength metallo-dielectric gratings integrated on optical fibers tip and supporting plasmonic resonances were numerically investigated in their behavior as acousto-optical transducers. Different configurations have been analyzed and compared among them in terms of sensitivity, defined as reflectivity intensity variation (at fixed wavelength) with respect to dielectric layer thickness changes. Our results demonstrate that the maximum sensitivity is obtained when an interaction between different plasmonic modes occurs. Sensitivity enhancement up to a factor of 3 with respect to Fabry- Perot cavity like transducer with same materials and sizes can be achieved.

  6. Measurements of ultrasound velocity and attenuation in numerical anisotropic porous media compared to Biot's and multiple scattering models.

    PubMed

    Mézière, Fabien; Muller, Marie; Bossy, Emmanuel; Derode, Arnaud

    2014-07-01

    This article quantitatively investigates ultrasound propagation in numerical anisotropic porous media with finite-difference simulations in 3D. The propagation media consist of clusters of ellipsoidal scatterers randomly distributed in water, mimicking the anisotropic structure of cancellous bone. Velocities and attenuation coefficients of the ensemble-averaged transmitted wave (also known as the coherent wave) are measured in various configurations. As in real cancellous bone, one or two longitudinal modes emerge, depending on the micro-structure. The results are confronted with two standard theoretical approaches: Biot's theory, usually invoked in porous media, and the Independent Scattering Approximation (ISA), a classical first-order approach of multiple scattering theory. On the one hand, when only one longitudinal wave is observed, it is found that at porosities higher than 90% the ISA successfully predicts the attenuation coefficient (unlike Biot's theory), as well as the existence of negative dispersion. On the other hand, the ISA is not well suited to study two-wave propagation, unlike Biot's model, at least as far as wave speeds are concerned. No free fitting parameters were used for the application of Biot's theory. Finally we investigate the phase-shift between waves in the fluid and the solid structure, and compare them to Biot's predictions of in-phase and out-of-phase motions.

  7. Randomized double-blind clinical trial comparing two anesthetic techniques for ultrasound-guided transvaginal follicular puncture

    PubMed Central

    de Oliveira, Gilvandro Lins; Serralheiro, Fernando Cesar; Fonseca, Fernando Luiz Affonso; Ribeiro, Onésimo Duarte; Adami, Fernando; Christofolini, Denise Maria; Bianco, Bianca; Barbosa, Caio Parente

    2016-01-01

    ABSTRACT Objective: To compare the anesthetic techniques using propofol and fentanyl versus midazolam and remifentanil associated with a paracervical block with lidocaine in performing ultrasound-guided transvaginal oocyte aspiration. Methods: A randomized double-blind clinical trial (#RBR-8kqqxh) performed in 61 women submitted to assisted reproductive treatment. The patients were divided into two groups: anesthetic induction with 1mcg/kg of fentanyl associated with 1.5mg/kg of propofol (FP Group, n=32), in comparison with anesthetic induction using 0.075mg/kg of midazolam associated with 0.25mcg/kg/min of remifentanil, and paracervical block with 3mL of 2% lidocaine (MRPB Group, n=29). Main outcome measures: human reproduction outcomes, modified Aldrete-Kroulik index, hemodynamic parameters, and salivary cortisol. Results: The results revealed a higher number of embryos formed in the FP Group (p50=2 versus 1; p=0.025), gestation rate two times higher in the FP Group (44.4% versus 22.2%; p=0.127), less time to reach AK=10 in the MRPB Group (p50=10 versus 2; p<0.001), and lower mean of hemodynamic parameters in the MRPB Group (p<0.05). Conclusion: Anesthesia with fentanyl and propofol as well as with midazolam, remifentanil, and paracervical block offered satisfactory anesthetic conditions when performing assisted reproduction procedures, providing comfort for the patient and physician. PMID:27759816

  8. Comparative analysis of laparoscopic and ultrasound-guided biopsy methods for gene expression analysis in transgenic goats.

    PubMed

    Melo, C H; Sousa, F C; Batista, R I P T; Sanchez, D J D; Souza-Fabjan, J M G; Freitas, V J F; Melo, L M; Teixeira, D I A

    2015-07-31

    The present study aimed to compare laparoscopic (LP) and ultrasound-guided (US) biopsy methods to obtain either liver or splenic tissue samples for ectopic gene expression analysis in transgenic goats. Tissue samples were collected from human granulocyte colony stimulating factor (hG-CSF)-transgenic bucks and submitted to real-time PCR for the endogenous genes (Sp1, Baff, and Gapdh) and the transgene (hG-CSF). Both LP and US biopsy methods were successful in obtaining liver and splenic samples that could be analyzed by PCR (i.e., sufficient sample sizes and RNA yield were obtained). Although the number of attempts made to obtain the tissue samples was similar (P > 0.05), LP procedures took considerably longer than the US method (P = 0.03). Finally, transgene transcripts were not detected in spleen or liver samples. Thus, for the phenotypic characterization of a transgenic goat line, investigation of ectopic gene expression can be made successfully by LP or US biopsy, avoiding the traditional approach of euthanasia.

  9. [Comparative study of 2 dosage forms of liquid dimethicone for ultrasound premedication].

    PubMed

    Gladisch, R; Elfner, R; Ulrich, H; Heene, D L

    1990-04-01

    A double-blind study was carried out to compare the effects of a premedication with 4 x 500 mg dimethylpolysiloxane (DPS)/24 hours and with 2 x 500 mg/12 hours before abdominal ultrasonography. The investigations covered 13 abdominal regions in specified planes. The incidence of the unobscured presentation of the selected organs and organ sections per patient served as a basis for a sonography index. This index was 67%, without significant difference between the two groups. We believe that the optimal conditions for sonography are given when the patient is fasting and two 500 mg doses of DPS are administered, one in the evening before and one in the morning at the day of investigation.

  10. Dynamic telecytology compares favorably to rapid onsite evaluation of endoscopic ultrasound fine needle aspirates

    PubMed Central

    Buxbaum, James L.; Eloubeidi, Mohamad A.; Lane, Christianne J.; Varadarajulu, Shyam; Linder, Ami; Crowe, Amanda E.; Jhala, Darshana; Jhala, Nirag C.; Crowe, David R.; Eltoum, Isam A.

    2013-01-01

    Background and Aims Rapid onsite evaluation (ROSE) has been demonstrated to correlate with final cytologic interpretations and improves the diagnostic yield of EUS-FNA, however, its availability is variable across centers. The aim of this prospective study was to evaluate whether remote telecytology can substitute for ROSE. Methods Consecutive patients who underwent EUS-FNA for diverse indications at a high volume referral center were enrolled All samples were prospectively evaluated by three methods. ROSE was performed by a cytopathologist in the procedure room; simultaneously dynamic telecytology was done by a different cytopathologist in a remote location at our institution. The third method, final cytologic interpretation in the laboratory, was the gold standard. Telecytology was performed using an Olympus microscope system (BX) which broadcasts live images over the internet. Accuracy of telecytology and agreement with other methods were the principle outcome measurements. Results Twenty-five consecutive samples were obtained from participants 40–87 years (median age =63, 48% male). There was 88% agreement between telecytology and final cytology (p < 0.001) and 92% agreement between ROSE and final cytology (p <0.001). There was consistency between telecytology and ROSE (p-value for McNemar’s χ2 = 1.0). Cohen’s kappa for agreement for telecytology and ROSE was 0.80 (SE = 0.11), confirming favorable correlation. Conclusion Dynamic telecytology compares favorably to ROSE in the assessment of EUS acquired fine needle aspirates. If confirmed by larger trials, this system might obviate the need for onsite interpretation of EUS-FNA specimens. PMID:22729624

  11. Ultrasound -- Vascular

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  12. Ultrasound - Breast

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  13. Ultrasound -- Pelvis

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  14. Prostate Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  15. Abdominal Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  16. Obstetrical Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  17. Musculoskeletal Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  18. Hip Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  19. Ultrasound - Scrotum

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  20. Ultrasound - Breast

    MedlinePlus

    ... the examination. top of page What does the equipment look like? Ultrasound scanners consist of a console ... ultrasound that require biopsy are not cancers. Many facilities do not offer ultrasound screening, and the procedure ...

  1. Cranial Ultrasound/Head Ultrasound

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  2. Diagnostic value of CT compared to ultrasound in the evaluation of acute abdominal pain in children younger than 10 years old.

    PubMed

    Simanovsky, Natalia; Dola, Tamar; Hiller, Nurith

    2016-02-01

    To assess the diagnostic value of ultrasound compared to CT in evaluating acute abdominal pain of different causes in children 10 years of age and under, hospital records and imaging files of 4052 patients under age of 10 who had imaging for abdominal pain were reviewed. One-hundred-thirty-two patients (3 %), (74 males/58 females) who underwent ultrasound and CT within 24 h were divided by age: group I, ages 0-48 months (25 patients); group II, 49-84 months (53 patients); and group III, 85-120 months (54 patients). Diagnoses at ultrasound, CT, and discharge were compared. Cases of a change in diagnosis following CT and impact of the changed diagnosis on patient management were assessed. Non-diagnostic ultrasound or a diagnostic conundrum was present in a small percentage (3 %) of our patients. In the group of patients imaged with two modalities, CT changed the diagnosis in 73/132 patients (55.3 %). Patient management changed in 63/132 patients (47.7 %). CT changed the diagnosis in 46/64 patients with surgical conditions (71.8 %, p < 0.001). Among patients with surgical conditions, the difference between ultrasonography (US) and CT diagnoses was significant in groups 2 (p = 0.046) and 3 (p =  .001). The impact of the change in diagnosis in surgical patients imaged with two modalities was significant in the group as a whole and in each age group separately. Non-diagnostic or equivocal US in a small percentage of patients is probably sufficient to justify the additional radiation burden.

  3. Comparing microbubble cavitation at 500 kHz and 70 kHz related to micellar drug delivery using ultrasound.

    PubMed

    Diaz de la Rosa, Mario A; Husseini, Ghaleb A; Pitt, William G

    2013-02-01

    We have previously reported that ultrasonic drug release at 70kHz was found to correlate with the presence of subharmonic emissions. No evidence of drug release or of the subharmonic emissions were detected in experiments at 500kHz. In an attempt to understand the difference in drug release behavior between low- and mid-frequency ultrasound, a mathematical model of a bubble oscillator was developed to explore the difference in the behavior of a single 10-μm bubble under 500- and 70-kHz ultrasound. The dynamics were found to be fundamentally different; the 500-kHz bubble follows a period-doubling route to chaos while a 70-kHz bubble follows an intermittent route to chaos. We propose that this type of "intermittent subharmonic" oscillation behavior is associated with the drug release observed experimentally.

  4. COMPARATIVE STUDY OF THE EFFECTS OF LOW-LEVEL LASER AND LOW-INTENSITY ULTRASOUND ASSOCIATED WITH BIOSILICATE® ON THE PROCESS OF BONE REPAIR IN THE RAT TIBIA

    PubMed Central

    Oliveira, Poliani de; Fernandes, Kelly Rosseti; Sperandio, Evandro Fornias; Pastor, Fabio Alexandre Casarin; Nonaka, Keico Okino; Parizotto, Nivaldo Antonio; Renno, Ana Claudia Muniz

    2015-01-01

    Objective: Verify the effects of the association between Biosilicate® and ultrasound and, Biosilicate® and laser in bone consolidation process of rats, through the biomechanical and histological analysis. Methods: Forthy male rats were used. The animals were randomized into four groups (n=10): control group fracture no treated (CGF); group treated with Biosilicate® (BG); group treated with Biosilicate® and laser (BLG); group treated with Biosilicate® and ultrasound (BUG). Results: The biomechanical analysis showed no significant difference among any groups after 14 days post-surgery. In the morphometric analysis, the control group showed moderate presence of new formed bone tissue inside the defects areas and the Biosilicate® group showed similar results. Despite those facts, the biomaterial osteogenic potential was demonstrated by the great amount of cells and bone tissue around the particles. Curiously, the Biosilicate® plus laser or ultrasound groups showed lower amounts of bone tissue deposition when compared with control fracture and Biosilicate® groups. Conclusion: The data from this study can conclude that Biosilicate® was able to accelerate and optimized the bone consolidation, through the modulation of the inflammatory process and the stimulation of new bone formation. However, when resources were associated, there are no positive results. PMID:27027088

  5. A Prospective Comparative Study of High Resolution Ultrasound and MRI in the Diagnosis of Rotator Cuff Tears in a Tertiary Hospital of North India

    PubMed Central

    Chauhan, Narvir Singh; Ahluwalia, Ajay; Sharma, Yash Paul; Thakur, Lokesh

    2016-01-01

    Summary Background To evaluate the accuracy of high resolution ultrasound (USG) and MRI in the diagnosis of rotator cuff tears (RCT) and to determine if high resolution USG compares favorably in sensitivity and specificity to MRI in the diagnosis of rotator cuff injury. Material/Methods In this prospective comparative study, 40 patients with clinically suspected rotator cuff tears underwent both ultrasound and MRI of the shoulder. Out of these 40 patients, 31 patients who had positive findings for rotator cuff tears on ultrasound and/or MRI were finally included in the study while the remaining 9 patients with negative or unrelated findings were excluded. The USG and MRI were interpreted by two radiologists experienced in musculoskeletal radiology and blinded to findings of each other. Comparison was done using MRI as a standard reference. Results The agreement between USG and MRI for diagnosis of RCTs was statistically excellent; USG showed a sensitivity of 86.7% and a specificity of 100% for full-thickness tears, and a sensitivity of 89.7% and a specificity of 98.8% for partial-thickness tears; observed accuracy for full thickness tears was 98.4% and 95.9% for partial thickness tears. The Kappa coefficient of association was 0.91 for full thickness tears and 0.90 for partial thickness tears. Conclusions Considering the comparable diagnostic accuracy of USG and MRI, the former modality can be used as a first-line investigation for diagnosis of RCT. MRI should be used secondarily as a problem-solving tool either following an equivocal shoulder USG or for delineation of anatomy in cases where surgical correction is needed. PMID:27800039

  6. Correlation Between the Findings of Optical Coherent Retinal Tomography (OCT), Stereo Biomicroscopic Images from Fundus of an Eye and Values from Visual Acuity of Diabetic Macular Edema

    PubMed Central

    Nisic, Faruk; Turkovic, Samir; Mavija, Milka; Jovanovic, Nina; Alimanovic, Emina Halilovic-

    2014-01-01

    Introduction: Diabetic maculopathy is the major cause of reduced visual acuity in patients with non-proliferative diabetic retinopathy and occurs on average in 29% of patients who have diabetes for 20 or more years. Aim: The aim of this study is to re examine the correlation between the findings of optical coherence retinal tomography, stereo bio-microscopic images from fundus of an eye and values from visual acuity of diabetic macular edema. In addition, the aim is to show the importance of various ophthalmic tests for establishing diagnosis in time. Material and methods: The research sample consisted of 90 subjects-patients from Cabinet for photographic documentation, fluorescein angiography and laser photocoagulation in Department of Ophthalmology at the University Clinical Centre in Sarajevo. The study was a one-year long, prospective, clinical study. Results: Research has shown a positive correlation between the various tests that are applied for the diagnosis of diabetic macular edema. Accurate and early diagnosis is of great importance for the treatment in time of this disease by applying laser photocoagulation, intravitreal injections of Anti-VEGF drugs or surgical treatment by Pars Plana Vitrectomy. PMID:25395723

  7. Abdominal ultrasound

    MedlinePlus

    ... Kidney - blood and urine flow Abdominal ultrasound References Chen L. Abdominal ultrasound imaging. In: Sahani DV, Samir ... the Health on the Net Foundation (www.hon.ch). The information provided herein should not be used ...

  8. Endoscopic ultrasound

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/007646.htm Endoscopic ultrasound To use the sharing features on this page, please enable JavaScript. Endoscopic ultrasound is a type of imaging test. It is ...

  9. Thyroid ultrasound

    PubMed Central

    Chaudhary, Vikas; Bano, Shahina

    2013-01-01

    Thyroid ultrasonography has established itself as a popular and useful tool in the evaluation and management of thyroid disorders. Advanced ultrasound techniques in thyroid imaging have not only fascinated the radiologists but also attracted the surgeons and endocrinologists who are using these techniques in their daily clinical and operative practice. This review provides an overview of indications for ultrasound in various thyroid diseases, describes characteristic ultrasound findings in these diseases, and illustrates major diagnostic pitfalls of thyroid ultrasound. PMID:23776892

  10. Carotid Ultrasound

    MedlinePlus

    ... this page from the NHLBI on Twitter. Carotid Ultrasound Also known as carotid duplex. Carotid ultrasound is a painless imaging test that uses high- ... of your carotid arteries. This test uses an ultrasound machine, which includes a computer, a screen, and ...

  11. Added value of semi-quantitative breast-specific gamma imaging in the work-up of suspicious breast lesions compared to mammography, ultrasound and 3-T MRI

    PubMed Central

    Seymer, A; Keinrath, P; Holzmannhofer, J; Pirich, C; Hergan, K; Meissnitzer, M W

    2015-01-01

    Objective: To prospectively analyse the diagnostic value of semi-quantitative breast-specific gamma imaging (BSGI) in the work-up of suspicious breast lesions compared with that of mammography (MG), breast ultrasound and MRI of the breast. Methods: Within a 15-month period, 67 patients with 92 breast lesions rated as Category IV or V according to the breast imaging reporting and data system detected with MG and/or ultrasound were included into the study. After the injection of 740–1110 MBq of Technetium-99m (99mTc) SestaMIBI intravenously, scintigrams were obtained in two projections comparable to MG. The BSGI was analysed visually and semi-quantitatively by calculating a relative uptake factor (X). With the exception of two patients with cardiac pacemakers, all patients underwent 3-T breast MRI. Biopsy results were obtained as the reference standard in all patients. Sensitivity, specificity, positive- and negative-predictive values, accuracy and area under the curve were calculated for each modality. Results: Among the 92 lesions, 67 (72.8%) were malignant. 60 of the 67 cancers of any size were detected by BSGI with an overall sensitivity of 90%, only exceeded by ultrasound with a sensitivity of 99%. The sensitivity of BSGI for lesions <1 cm declined significantly to 60%. Overall specificity of ultrasound was only 20%. Specificity, accuracy and positive-predictive value were the highest for BSGI (56%, 80% and 85%, respectively). X was significantly higher for malignant lesions (mean, 4.27) and differed significantly between ductal types (mean, 4.53) and the other histopathological entities (mean, 3.12). Conclusion: Semi-quantitative BSGI with calculation of the relative uptake factor (X) can help to characterize breast lesions. BSGI negativity may obviate the need for biopsy of breast lesions >1 cm with low or intermediate prevalence for malignancy. Advances in knowledge: Compared with morphological imaging modalities, specificity, positive

  12. Lung cancer diagnosis and staging with endobronchial ultrasound-guided transbronchial needle aspiration compared with conventional approaches: an open-label, pragmatic, randomised controlled trial

    PubMed Central

    Navani, Neal; Nankivell, Matthew; Lawrence, David R; Lock, Sara; Makker, Himender; Baldwin, David R; Stephens, Richard J; Parmar, Mahesh K; Spiro, Stephen G; Morris, Stephen; Janes, Sam M

    2015-01-01

    and was admitted to hospital. Interpretation Transbronchial needle aspiration guided by endobronchial ultrasound should be considered as the initial investigation for patients with suspected lung cancer, because it reduces the time to treatment decision compared with conventional diagnosis and staging techniques. Funding UK Medical Research Council. PMID:25660225

  13. Comparison of the biometric values obtained by two different A-mode ultrasound devices (Eye Cubed vs. PalmScan): A Transversal, descriptive, and comparative study

    PubMed Central

    2010-01-01

    Background To assess the reliability of the measurements obtained with the PalmScan™, when compared with another standardized A-mode ultrasound device, and assess the consistency and correlation between the two methods. Methods Transversal, descriptive, and comparative study. We recorded the axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) obtained with two A-mode ultrasounds (PalmScan™ A2000 and Eye Cubed™) using an immersion technique. We compared the measurements with a two-sample t-test. Agreement between the two devices was assessed with Bland-Altman plots and 95% limits of agreement. Results 70 eyes of 70 patients were enrolled in this study. The measurements with the Eye Cubed™ of AL and ACD were shorter than the measurements taken by the PalmScan™. The differences were not statistically significant regarding AL (p < 0.4) but significant regarding ACD (p < 0.001). The highest agreement between the two devices was obtained during LT measurement. The PalmScan™ measurements were shorter, but not statistically significantly (p < 0.2). Conclusions The values of AL and LT, obtained with both devices are not identical, but within the limits of agreement. The agreement is not affected by the magnitude of the ocular dimensions (but only between range of 20 mm to 27 mm of AL and 3.5 mm to 5.7 mm of LT). A correction of about 0.5 D could be considered if an intraocular lens is being calculated. However due to the large variability of the results, the authors recommend discretion in using this conversion factor, and to adjust the power of the intraocular lenses based upon the personal experience of the surgeon. PMID:20334670

  14. Ultrasound physics.

    PubMed

    Shriki, Jesse

    2014-01-01

    Bedside ultrasound has become an important modality for obtaining critical information in the acute care of patients. It is important to understand the physics of ultrasound in order to perform and interpret images at the bedside. The physics of both continuous wave and pulsed wave sound underlies diagnostic ultrasound. The instrumentation, including transducers and image processing, is important in the acquisition of appropriate sonographic images. Understanding how these concepts interplay with each other enables practitioners to obtain the best possible images.

  15. Infrared thermography and ultrasound C-scan for non-destructive evaluation of 3D carbon fiber materials: a comparative study

    NASA Astrophysics Data System (ADS)

    Zhang, Hai; Genest, Marc; Robitaille, Francois; Maldague, Xavier; West, Lucas; Joncas, Simon; Leduc, Catherine

    2015-05-01

    3D Carbon fiber polymer matrix composites (3D CF PMCs) are increasingly used for aircraft construction due to their exceptional stiffness and strength-to-mass ratios. However, defects are common in the 3D combining areas and are challenging to inspect. In this paper, Stitching is used to decrease these defects, but causes some new types of defects. Infrared NDT (non-destructive testing) and ultrasound NDT are used. In particular, a micro-laser line thermography technique (micro-LLT) and a micro-laser spot thermography (micro-LST) with locked-in technique are used to detect the micro-defects. In addition, a comparative study is conducted by using pulsed thermography (PT), vibrothermography (VT). In order to confirm the types of the defects, microscopic inspection is carried out before NDT work, after sectioning and polishing a small part of the sample..

  16. Sterile working in ultrasonography: the use of dedicated ultrasound covers and sterile ultrasound gel.

    PubMed

    Marhofer, Peter; Fritsch, Gerhard

    2015-01-01

    Ultrasound is currently an important tool for diagnostic and interventional procedures. Ultrasound imaging provides significant advantages as compared to other imaging methods. The widespread use of ultrasound also carries the risk of drawbacks such as cross-infections. A large body of literature reports this possibly life-threatening side effect and specific patient populations are particularly at risk (e.g., neonates). Various methods of ultrasound probe disinfection are described; however, none of the mechanical or chemical probe disinfection procedures is optimal and, in particular, disinfection with high concentration of alcohol might be associated with ultrasound probe damage. The preparation of ultrasound probes with dedicated probe covers is a useful alternative for sterile working conditions. One ultrasound probe cover discussed in this paper is directly glued on to the ultrasound probe without the use of ultrasound coupling gel. By the use of sterile ultrasound coupling gel at the outer surface, additional effects on aseptic working conditions can be obtained.

  17. Cranial Ultrasound/Head Ultrasound

    MedlinePlus

    ... sickle cell disease. It is also used to measure conditions affecting blood flow to and within the brain, such as: Stenosis : ... saved. Doppler ultrasound, a special application of ultrasound, measures ... represent the flow of blood through the blood vessels. top of ...

  18. Ultrasound-Guided Versus Fluoroscopy-Guided Caudal Epidural Steroid Injection for the Treatment of Unilateral Lower Lumbar Radicular Pain: Case-Controlled, Retrospective, Comparative Study.

    PubMed

    Park, Ki Deok; Kim, Tai Kon; Lee, Woo Yong; Ahn, JaeKi; Koh, Sung Hoon; Park, Yongbum

    2015-12-01

    The aim of the article is to investigate the efficacy of ultrasound (US)-guided Caudal Epidural Steroid Injection (CESI) compared with fluoroscopy (FL)-guided CESI in patients with unilateral lower lumbar radicular pain. This case-controlled, retrospective, comparative study was done at the university hospital. A total of 110 patients treated with US- or FL-guided CESI were administered a mixture of 20 cc (0.5% lidocaine 18.0  mL + dexamethason 10  mg 2  mL). Outcome measurement was assessed by Oswestry Disability Index (ODI), verbal numeric pain scale (VNS) before injections and at 3, 6, and 12 months after the last injections. Successful outcome was defined as measured by >50% improvement in the VNS score and >40% improvement in the ODI. ODI and VNS showed improvement at 3, 6, and 12 months after the last injection in both groups. No statistical differences in ODI, VNS were observed between groups (P < 0.05). No significant differences in the proportion of patients with successful treatment were observed between the groups from the 3-month to 6-month to 12-month outcomes. US-guided CESI is deserving of consideration in conservative management of unilateral lower lumbar radicular pain.

  19. Comparative study of ultrasound-guided abdominal field blocks versus port infiltration in laparoscopic cholecystectomies for post-operative pain relief

    PubMed Central

    Saxena, Ruchi; Joshi, Saurabh; Srivastava, Kuldeep; Tiwari, Shashank; Sharma, Nitin; Valecha, Umesh K

    2016-01-01

    Background and Aims: Post-operative pain is a major concern for day care surgeries like laparoscopic cholecystectomy. This study aimed to compare the efficacy of ultrasound guided abdominal field blocks (USAFB) with port site infiltrations for post-operative analgesia in terms of quality of pain relief, opioid consumption and patient satisfaction for day care surgeries Methods: Eighty patients presenting for laparoscopic cholecystectomy were randomly allocated to two groups either to receive port-site infiltration of local anaesthetic (n = 40, Group A) or USAFB (n = 40, Group B group). Numeric rating scores (NRS) were measured postoperatively to primarily assess the pain severity and opioid requirements. Data were analysed using Chi-Square test/Fisher's exact test for categorical data and Mann–Whitney test/unpaired t-test for quantitative data. Results: The study group (Group B) had significantly reduced NRS and opioid consumption over 24 h. The overall fentanyl consumption in patients receiving port infiltrations was approximately twice (200 ΁ 100 μg) as compared to patients in USAFB group (120 ΁ 74 μg) (P < 0.0001). Maximum fentanyl consumption was 400 μg (Group A) and 262 μg (Group B) over 24 h and the minimum requirement was 50 μg and zero, respectively. Conclusion: Superior post-operative analgesia was observed with USAFB which may help in minimising opioid-related adverse effects and facilitating faster recovery. PMID:27601741

  20. Non-contact low-frequency ultrasound therapy compared with UK standard of care for venous leg ulcers: a single-centre, assessor-blinded, randomised controlled trial.

    PubMed

    White, Judith; Ivins, Nicola; Wilkes, Antony; Carolan-Rees, Grace; Harding, Keith G

    2016-10-01

    'Hard-to-heal' wounds are those which fail to heal with standard therapy in an orderly and timely manner and may warrant the use of advanced treatments such as non-contact low-frequency ultrasound (NLFU) therapy. This evaluator-blinded, single-site, randomised controlled trial, compared NLFU in addition to UK standard of care [SOC: (NLFU + SOC)] three times a week, with SOC alone at least once a week. Patients with chronic venous leg ulcers were eligible to participate. All 36 randomised patients completed treatment (17 NLFU + SOC, 19 SOC), and baseline demographics were comparable between groups. NLFU + SOC patients showed a -47% (SD: 38%) change in wound area; SOC, -39% (38%) change; and difference, -7·4% [95% confidence intervals (CIs) -33·4-18·6; P = 0·565]. The median number of infections per patient was two in both arms of the study and change in quality of life (QoL) scores was not significant (P = 0·490). NLFU + SOC patients reported a substantial mean (SD) reduction in pain score of -14·4 (14·9) points, SOC patients' pain scores reduced by -5·3 (14·8); the difference was -9·1 (P = 0·078). Results demonstrated the importance of high-quality wound care. Outcome measures favoured NLFU + SOC over SOC, but the differences were not statistically significant. A larger sample size and longer follow-up may reveal NLFU-related improvements not identified in this study.

  1. Ultrasound -- Vascular

    MedlinePlus

    ... plan for their effective treatment. detect blood clots (deep venous thrombosis (DVT) in the major veins of ... What are the limitations of Vascular Ultrasound? Vessels deep in the body are harder to see than ...

  2. A comparative study of seed localization and dose calculation on pre- and post-implantation ultrasound and CT images for low-dose-rate prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Ali, Imad; Algan, Ozer; Thompson, Spencer; Sindhwani, Puneet; Herman, Terence; Cheng, Chih-Yao; Ahmad, Salahuddin

    2009-09-01

    This work investigates variation in the volume of the prostate measured at different stages through the prostate brachytherapy procedure for 30 patients treated with I-125 radioactive seeds. The implanted seeds were localized on post-implantation ultrasound (US) images and the effect of prostate enlargement due to edema on dose coverage for 15 patients was studied. The volume of the prostate was measured at four stages as follows: (a) 2-3 weeks prior to implantation using US imaging, (b) then at the start of the intra-operative prostate brachytherapy procedure on the day of the implant, (c) immediately post-implantation using US imaging in the operating room and (d) finally by CT imaging at nearly 4 weeks post-implantation. Comparative prostate volume studies were performed using US imaging stepper and twister modes. For the purpose of this study, the implanted seeds were localized successfully on post-implant ultrasound twister images, retrospectively. The plans using post-implant US imaging were compared with intra-operative plans on US and plans created on CT images. The prostate volume increases about 10 cm3 on average due to edema induced by needle insertion and seed loading during implantation. The visibility of the implanted seeds on US twister images acquired post-implantation is as good as those on CT images and can be localized and used for dose calculation. The dose coverage represented by parameters such as D90 (dose covering 90% of the volume) and V100 (volume covered by 100% dose) is poorer on plans performed on post-implantation twister US studies than on the intra-operative live plan or the CT scan performed 4 weeks post-operatively. For example, the mean D90 difference on post-implantation US is lower by more than 15% than that on pre-implantation US. The volume enlargement of the prostate due to edema induced by needle insertion and seed placement has a significant effect on the quality of dosimetric coverage in brachytherapy prostate seed

  3. Hepatic transit time analysis using contrast-enhanced ultrasound with BR1: A prospective study comparing patients with liver metastases from colorectal cancer with healthy volunteers.

    PubMed

    Hohmann, Joachim; Müller, Christine; Oldenburg, Anja; Skrok, Jan; Frericks, Bernd B; Wolf, Karl-Jürgen; Albrecht, Thomas

    2009-09-01

    We prospectively compared hepatic transit time (HTT) measurements in subjects with liver metastases from colorectal cancer (group a) and healthy volunteers (group b) using contrast-enhanced ultrasound with BR1. The purpose of this study was to verify our hypothesis that the hemodynamic changes of the liver, which occur during metastasis seeding, would shorten the HTT, and we expect that such changes could be used for the detection of occult liver metastases from colorectal cancer in the future. The study had institutional review board approval and all subjects gave informed written consent. Group a and group b consisted of 22 subjects each. Baseline and post contrast images were acquired starting 10 s before and ending 40 s after administration of BR1, using nonlinear imaging at a frame rate of 5/s. The baseline images were used to determine the signal intensity without contrast enhancement as the reference signal. Arrival times (AT) of the contrast agent for the hepatic artery, the portal vein and one hepatic vein were determined using (i) quantitative analysis and (ii) subjective analysis by two blinded readers. HTT was calculated based on arrival time measurements. Quantitative and subjective analysis showed significantly shorter arterial to venous and portal to venous HTT in group a compared with group b (p < 0.001). Arterial to venous HTT (quantitative analysis) was < or = 9 s in 19 of 22 subjects of group a and >9 s in 18 of 22 subjects of group b (sensitivity 86%, specificity 82%, positive predictive value 83%, negative predictive value 86%, area under the curve [AUC] 0.87). Portal to venous HTT (quantitative analysis) was < 7 s in 21 of 22 subjects of group a and > 7s in 15 of 22 subjects of group b (sensitivity 95%, specificity 68%, PPV 75%, NPV 94%, AUC 0.85). There was an inverse relation with number of liver segments involved for arterial to venous and portal to venous HTT in group a (p < 0.05), but no correlation between HTT and overall volume of

  4. Trauma Ultrasound.

    PubMed

    Wongwaisayawan, Sirote; Suwannanon, Ruedeekorn; Prachanukool, Thidathit; Sricharoen, Pungkava; Saksobhavivat, Nitima; Kaewlai, Rathachai

    2015-10-01

    Ultrasound plays a pivotal role in the evaluation of acute trauma patients through the use of multi-site scanning encompassing abdominal, cardiothoracic, vascular and skeletal scans. In a high-speed polytrauma setting, because exsanguinations are the primary cause of trauma morbidity and mortality, ultrasound is used for quick and accurate detection of hemorrhages in the pericardial, pleural, and peritoneal cavities during the primary Advanced Trauma Life Support (ATLS) survey. Volume status can be assessed non-invasively with ultrasound of the inferior vena cava (IVC), which is a useful tool in the initial phase and follow-up evaluations. Pneumothorax can also be quickly detected with ultrasound. During the secondary survey and in patients sustaining low-speed or localized trauma, ultrasound can be used to help detect abdominal organ injuries. This is particularly helpful in patients in whom hemoperitoneum is not identified on an initial scan because findings of organ injuries will expedite the next test, often computed tomography (CT). Moreover, ultrasound can assist in detection of fractures easily obscured on radiography, such as rib and sternal fractures.

  5. Carotid Ultrasound Imaging

    MedlinePlus

    ... Index A-Z Ultrasound - Carotid Carotid ultrasound uses sound waves to produce pictures of the carotid arteries ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  6. Comparative clinical study of ultrasound-guided A1 pulley release vs open surgical intervention in the treatment of trigger finger

    PubMed Central

    Nikolaou, Vasileios S; Malahias, Michael-Alexander; Kaseta, Maria-Kyriaki; Sourlas, Ioannis; Babis, George C

    2017-01-01

    AIM To investigate the effectiveness of ultrasound-guided release of the first annular pulley and compare results with the conventional open operative technique. METHODS In this prospective randomized, single-center, clinical study, 32 patients with trigger finger or trigger thumb, grade II-IV according to Green classification system, were recruited. Two groups were formed; Group A (16 patients) was treated with an ultrasound-guided percutaneous release of the affected A1 pulley under local anesthesia. Group B (16 patients) underwent an open surgical release of the A1 pulley, through a 10-15 mm incision. Patients were assessed pre- and postoperatively (follow-up: 2, 4 and 12 wk) by physicians blinded to the procedures. Treatment of triggering (primary variable of interest) was expressed as the “success rate” per digit. The time for taking postoperative pain killers, range of motion recovery, QuickDASH test scores (Greek version), return to normal activities (including work), complications and cosmetic results were assessed. RESULTS The success rate in group A was 93.75% (15/16) and in group B 100% (16/16). Mean times in group A patients were 3.5 d for taking pain killers, 4.1 d for returning to normal activities, and 7.2 and 3.9 d for complete extension and flexion recovery, respectively. Mean QuickDASH scores in group A were 45.5 preoperatively and, 7.5, 0.5 and 0 after 2, 4, and 12 wk postoperatively. Mean times in group B patients were 2.9 d for taking pain killers, 17.8 d for returning to normal activities, and 5.6 and 3 d for complete extension and flexion recovery. Mean QuickDASH scores in group B were 43.2 preoperatively and, 8.2, 1.3 and 0 after 2, 4, and 12 wk postoperatively. The cosmetic results found excellent or good in 87.5% (14/16) of group A patients, while in 56.25% (9/16) of group B patients were evaluated as fair or poor. CONCLUSION Treatment of the trigger finger using ultrasonography resulted in fewer absence of work days, and better

  7. Osteogenic effects of low-intensity pulsed ultrasound, extracorporeal shockwaves and their combination - an in vitro comparative study on human periosteal cells.

    PubMed

    Tam, Kam-Fai; Cheung, Wing-Hoi; Lee, Kwong-Man; Qin, Ling; Leung, Kwok-Sui

    2008-12-01

    Our previous studies have shown that on human periosteal cells, low-intensity pulsed ultrasound (LIPUS) has an immediate stimulatory effect whereas extracorporeal shockwaves (ESW) have an delayed stimulatory effect. Therefore, we hypothesized that a combined ESW and LIPUS treatment might provide additive or synergistic effects on periosteal cells, by using ESW to trigger a biological activity while using LIPUS to maintain the stimulated activity. Human periosteal cells were subjected to a single session of ESW treatment on day 0 and/or daily LIPUS treatments or no treatment (control). The cell viability, proliferation, and alkaline phosphatase activity on day 6 and day 18 as well as matrix mineralization on day 35 were measured. Results revealed that LIPUS alone had early positive effects on the activities on day 6 only. In contrast, ESW alone had an early destructive effect but exerted delayed stimulatory effects on the cellular activities on day 18. The combined treatment of ESW plus LIPUS produced effects that were comparable to the ESW treatment alone. Although these findings suggest that ESW and LIPUS stimulate the periosteal cells in two different ways and at different times, their additive or synergistic effects could not be proven.

  8. Comparative study of multi-enzyme production from typical agro-industrial residues and ultrasound-assisted extraction of crude enzyme in fermentation with Aspergillus japonicus PJ01.

    PubMed

    Li, Pei-jun; Xia, Jin-lan; Shan, Yang; Nie, Zhen-yuan

    2015-10-01

    Submerged fermentation (SmF) and solid-state fermentation (SSF) of Aspergillus japonicus PJ01 for multi-enzyme complexes (MEC) production were comparatively studied. The results showed that orange peel and wheat bran were the best substrates for MEC production in SmF and SSF, respectively. After 72 h of cultivation under SmF, the maximal pectinase, CMCase, and xylanase activities reached 2610, 85, and 335 U/gds (units/gram dry substrate), respectively; while after 72 h of cultivation under SSF, these three enzymes' activities reached 966, 58, and 1004 U/gds, respectively. Effects of ultrasound on extraction of crude enzymes from SSF medium were determined, the maximal activities of pectinase, CMCase, and xylanase increased to 1.20, 1.48, and 1.30-fold, respectively. Apparent different mycelia growths of SSF and SmF were observed by scanning electron microscopy; and different isoforms of the crude enzyme extracts from SSF and SmF were presented by zymogram analysis.

  9. A comparative study on the effect of conventional thermal pasteurisation, microwave and ultrasound treatments on the antioxidant activity of five fruit juices.

    PubMed

    Saikia, Sangeeta; Mahnot, Nikhil Kumar; Mahanta, Charu Lata

    2016-06-01

    A comparative study on the effect of conventional thermal pasteurisation, microwave and ultrasound treatments on the phytochemical and antioxidant activities of juices from carambola (Averrhoa carambola L.), black jamun (Syzygium cumuni L.Skeels.), watermelon (Citrullus lanatus var lanatus), pineapple (Ananas comosus L. Merr) and litchi (Litchi chinensis Sonn.) was carried out. Depending on the type of fruit sample and treatment, increase or decrease in phytochemical values was observed. Overall, sonication had a positive effect on the total flavonoid content in all the juice samples followed by microwave treatment with exceptions in some cases. High-performance liquid chromatography study showed the presence of different phenolic acids depending on the sample type. The phenolic acids in some processed carambola juice samples showed decrease or complete destruction, while in some cases, an increase or appearance of newer phenolic acid originally not detected in the fresh juice was observed as seen in conventional thermal pasteurisation, microwaved at 600 W and sonicated juices. Both microwaved and sonicated samples were found to have positive effect on the phenolic content and antioxidant activity with exceptions in some cases. Therefore, microwave and sonication treatment could be used in place of thermal pasteurisation depending on the sample requirements.

  10. Comparative study of the topical application of Aloe vera gel, therapeutic ultrasound and phonophoresis on the tissue repair in collagenase-induced rat tendinitis.

    PubMed

    Maia Filho, Antonio Luiz Martins; Villaverde, Antonio Balbin; Munin, Egberto; Aimbire, Flávio; Albertini, Regiane

    2010-10-01

    The aim of our study was to compare topical use of Aloe vera gel, pulsed mode ultrasound (US) and Aloe vera phonophoresis on rat paw with collagenase-induced tendinitis. Edema size, tensile tendon strength, tendon elasticity, number of inflammatory cells and tissue histology were studied at 7 and 14 days after tendinitis induction. Pulse mode US parameters were: 1 MHz frequency, 100 Hz repetition rate, 10% duty cycle, and 0.5 W/cm(2) intensity, applied for 2 min each session. A 0.5 mL of Aloe vera gel at 2% concentration was applied for 2 min per session, topically and by phonophoresis. Topical application of Aloe vera gel did not show any statistically significant improvement in the inflammatory process, whereas phonophoresis enhanced the gel action reducing edema and number of inflammatory cells, promoting the rearrangement of collagen fibers and promoting also the recovery of the tensile strength and elasticity of the inflamed tendon to recover their normal pre-injury status. Results seem to indicate that Aloe vera phonophoresis is a promising technique for tendinitis treatment, without the adverse effect provoked by systemic anti-inflammatory drugs.

  11. Treatment of abdominal abscesses: comparative evaluation of operative drainage versus percutaneous catheter drainage guided by computed tomography or ultrasound.

    PubMed Central

    Johnson, W C; Gerzof, S G; Robbins, A H; Nabseth, D C

    1981-01-01

    Computed tomography and, to a lesser extent, ultrasonography provide detailed anatomic localization of intra-abdominal abscesses that permit precise percutaneous placement of catheters large enough to effect drainage. Using routes similar to surgical approaches, the authors have used this technique as definitive therapy for intra-abdominal abscesses. To assess its efficacy, the results in the 27 patients treated percutaneously over the last five years have been compared with the results in the 43 patients treated by operative intervention over the past ten years. In the percutaneous group, complications (4%), inadequate drainage (11%), and duration of drainage (17 days) were less than in the operative group (16%, 21% and 29 days respectively). These results indicate that percutaneous drainage is at least as efficacious as operative drainage and avoids the risks of a major operative procedure. Images Fig. 2. Fig. 4. PMID:7283510

  12. A comparative study of contrast enhanced ultrasound and contrast enhanced magnetic resonance imaging for the detection and characterization of hepatic hemangiomas.

    PubMed

    Fang, Liang; Zhu, Zheng; Huang, Beijian; Ding, Hong; Mao, Feng; Li, Chaolun; Zeng, Mengsu; Zhou, Jianjun; Wang, Ling; Wang, Wenping; Chen, Yue

    2015-04-01

    This study aims to compare contrast enhanced ultrasound (CEUS) and contrast enhanced magnetic resonance imaging (CEMRI) for the detection and characterization of hepatic hemangiomas. Included in this retrospective study were 83 histopathologically confirmed lesions of hemangioma in 66 hospitalized patients who underwent both CEUS and CEMRI and received surgery. The enhancement patterns on CEUS and CEMRI in each lesion were compared and analyzed. In addition, data obtained by the two modalities were then compared with the pathological findings to determine their value in differential diagnosis of hepatic hemangiomas. CEUS diagnosed 78 lesions of hemangioma against 80 by CEMRI. There were no statistical significant differences in the diagnostic value between CEUS and CEMRI in terms of sensitivity (88.0% vs. 92.8%), specificity (99.0% vs. 99.4%), accuracy (97.3% vs. 98.4%), positive predictive value (93.6% vs. 96.3%), and negative predictive value (98.0% vs. 98.8%) (p > 0.05, all). In the arterial phase, the main enhancement pattern on both CEUS and CEMRI was peripheral nodular enhancement (73 vs. 76), but lesions with diffuse enhancement on CEUS outnumbered those on CEMRI (3 vs. 1) and lesions with circular enhancement on CEMRI outnumbered those on CEUS (3 vs. 2). In the portal venous phase and delayed phase, the main enhancement pattern was hyperechoic change on CEUS and hyperintense on CEMRI (66 vs. 65), some lesions presented isoechoic change (12 vs. 15). These results suggested CEUS, an equivalent to CEMRI, may have an added diagnostic value in hemangiomas.

  13. Doppler ultrasound monitoring technology.

    PubMed

    Docker, M F

    1993-03-01

    Developments in the signal processing of Doppler ultrasound used for the detection of fetal heart rate (FHR) have improved the operation of cardiotocographs. These developments are reviewed and the advantages and disadvantages of the various Doppler and signal processing methods are compared.

  14. Evaluation of osteoporosis using ultrasound

    NASA Astrophysics Data System (ADS)

    Maia, Joaquim M.; Costa, Eduardo T.; Nantes Button, Vera L. d. S.; Dantas, Ricardo G.

    2000-04-01

    We have developed an equipment using ultrasound transducers to help in the diagnosis of osteoporosis. The equipment consists of an X-Y axes displacement system controlled by a microcomputer and uses two ultrasound transducers in opposite sides to inspect the calcaneus region of the patient. We have used two pairs of transducers with 500 kHz and 1 MHz central frequencies. Each pair of transducers was fixed in the X-Y displacement system submerged in a small water tank with a support for the foot of the patient. The transmitter was excited with pulses of 400 - 600 kHz or 800 - 1200 kHz and the ultrasound waves propagating through the bone in the calcaneus region are received by the opposite transducer, amplified and acquired in a digital oscilloscope. The data are transferred to the microcomputer and the ultrasound attenuation and the ultrasound transmission velocity are determined. The system was tested in patients, selected from a group that had already been diagnosed using a DEXA equipment. The results showed that there is a decrease in the ultrasound transmission velocity and the ultrasound attenuation in osteoporotic patients when compared to healthy patients of the same sex and age group. The conclusion is that ultrasound attenuation and the transmission velocity in the calcaneus region may be used as parameters in the evaluation of osteoporosis using our new system.

  15. Ultrasound - Scrotum

    MedlinePlus

    ... especially when the mass is solid). Blood flow images of the testicles are not always reliable in determining the presence or absence of blood supply to a testicle that has twisted. When searching for an absent testicle, ultrasound may not be ...

  16. Doppler ultrasound surveillance in deep tunneling compressed-air work with Trimix breathing: bounce dive technique compared to saturation-excursion technique.

    PubMed

    Vellinga, T P van Rees; Sterk, W; de Boer, A G E M; van der Beek, A J; Verhoeven, A C; van Dijk, F J H

    2008-01-01

    The Western Scheldt Tunneling Project in The Netherlands provided a unique opportunity to evaluate two deep-diving techniques with Doppler ultrasound surveillance. Divers used the bounce diving techniques for repair and maintenance of the TBM. The tunnel boring machine jammed at its deepest depth. As a result the work time was not sufficient. The saturation diving technique was developed and permitted longer work time at great depth. Thirty-one divers were involved in this project. Twenty-three divers were examined using Doppler ultrasound. Data analysis addressed 52 exposures to Trimix at 4.6-4.8 bar gauge using the bounce technique and 354 exposures to Trimix at 4.0-6.9 bar gauge on saturation excursions. No decompression incidents occurred with either technique during the described phase of the project. Doppler ultrasound revealed that the bubble loads assessed in both techniques were generally low. We find out, that despite longer working hours, shorter decompression times and larger physical workloads, the saturation-excursion technique was associated with significant lower bubble grades than in the bounce technique using Doppler Ultrasound. We conclude that the saturation-excursion technique with Trimix is a good option for deep and long exposures in caisson work. The Doppler technique proved valuable, and it should be incorporated in future compressed-air work.

  17. Ultrasound Annual, 1984

    SciTech Connect

    Sanders, R.C.; Hill, M.C.

    1984-01-01

    The 1984 edition of Ultrasound Annual explores new applications of ultrasound in speech and swallowing and offers guidelines on the use of ultrasound and nuclear medicine in thyroid and biliary tract disease. Other areas covered include Doppler sonography of the abdomen, intraoperative abdominal ultrasound, sonography of the placenta, ultrasound of the neonatal head and abdomen, and sonographic echo patterns created by fat.

  18. SU-E-J-76: Incorporation of Ultrasound Elastography in Target Volume Delineation for Partial Breast Radiotherapy Planning: A Comparative Study

    SciTech Connect

    Juneja, P; Harris, E; Bamber, J

    2014-06-01

    Purpose: There is substantial observer variability in the delineation of target volumes for post-surgical partial breast radiotherapy because the tumour bed has poor x-ray contrast. This variability may result in substantial variations in planned dose distribution. Ultrasound elastography (USE) has an ability to detect mechanical discontinuities and therefore, the potential to image the scar and distortion in breast tissue architecture. The goal of this study was to compare USE techniques: strain elastography (SE), shear wave elastography (SWE) and acoustic radiation force impulse (ARFI) imaging using phantoms that simulate features of the tumour bed, for the purpose of incorporating USE in breast radiotherapy planning. Methods: Three gelatine-based phantoms (10% w/v) containing: a stiff inclusion (gelatine 16% w/v) with adhered boundaries, a stiff inclusion (gelatine 16% w/v) with mobile boundaries and fluid cavity inclusion (to mimic seroma), were constructed and used to investigate the USE techniques. The accuracy of the elastography techniques was quantified by comparing the imaged inclusion with the modelled ground-truth using the Dice similarity coefficient (DSC). For two regions of interest (ROI), the DSC measures their spatial overlap. Ground-truth ROIs were modelled using geometrical measurements from B-mode images. Results: The phantoms simulating stiff scar tissue with adhered and mobile boundaries and seroma were successfully developed and imaged using SE and SWE. The edges of the stiff inclusions were more clearly visible in SE than in SWE. Subsequently, for all these phantoms the measured DSCs were found to be higher for SE (DSCs: 0.91–0.97) than SWE (DSCs: 0.68–0.79) with an average relative difference of 23%. In the case of seroma phantom, DSC values for SE and SWE were similar. Conclusion: This study presents a first attempt to identify the most suitable elastography technique for use in breast radiotherapy planning. Further analysis will

  19. Comparative study of the effects of low-intensity pulsed ultrasound and low-level laser therapy on injured muscle repair

    NASA Astrophysics Data System (ADS)

    Renno, Ana Claudia Muniz; Toma, Renata Luri; Feitosa, Suellen Maurin; Fernandes, Kelly; de Oliveira, Poliani; Parizotto, N.; Ribeiro, Daniel Araki

    2011-03-01

    Muscle tissue is one of the most frequently affected by injury, whether during sports activities, or work activities. In this context, biochemical and biophysical resources have been studied to minimize the time of muscle regeneration. Among these, low intensity pulsed ultrasound (US) and low level laser therapy (LLLT) may be highlighted. Despite a series of evidences about the positive effects of these resources in the process of tissue regeneration, the cellular and morphological changes triggered by LLLT and U.S. are still largely unknown. Thus, the aim of this study was to investigate the effects of US and LLLT on muscle repair after cryolesion by means of histopathological analysis and immunohistochemistry for COX-2. A total of thirty five male Wistar rats were randomly distributed into 4 groups: intact control group; injured control group: muscle injured animals without any treatment; laser treated group: muscle injured animals treated with 830 nm laser and ultra-sound treated group: muscle injured animals treated with US. The treatments started 24 hours post-surgery and were performed during 6 sessions. The animals exposed to lasertherapy pointed out minor degenerative changes of muscle tissue. In the same way, exposure to ultrasound was able to reduce tissue injuries induced by cryolesion, but less intense than laser therapy. Strong COX-2 positive cells were found in rats submitted to cryolesion only, whereas COX-2 immunoexpression was lower in laser treated or ultrasound treated groups. In summary, this study reveals that both lasertherapy and ultrasound have positive effects on muscle repair in rats.

  20. [Ultrasound guided percutaneous nephrolithotripsy].

    PubMed

    Guliev, B G

    2014-01-01

    The study was aimed to the evaluation of the effectiveness and results of ultrasound guided percutaneous nephrolithotripsy (PNL) for the treatment of patients with large stones in renal pelvis. The results of PNL in 138 patients who underwent surgery for kidney stones from 2011 to 2013 were analyzed. Seventy patients (Group 1) underwent surgery with combined ultrasound and radiological guidance, and 68 patients (Group 2)--only with ultrasound guidance. The study included patients with large renal pelvic stones larger than 2.2 cm, requiring the formation of a single laparoscopic approach. Using the comparative analysis, the timing of surgery, the number of intra- and postoperative complications, blood loss and length of stay were evaluated. Percutaneous access was successfully performed in all patients. Postoperative complications (exacerbation of chronic pyelonephritis, gross hematuria) were observed in 14.3% of patients in Group 1 and in 14.7% of patients in Group 2. Bleeding requiring blood transfusion, and injuries of adjacent organs were not registered. Efficacy of PNL in the Group 1 was 95.7%; 3 (4.3%) patients required additional interventions. In Group 2, the effectiveness of PNL was 94.1%, 4 (5.9%) patients additionally underwent extracorporeal lithotripsy. There were no significant differences in the effectiveness of PNL, the volume of blood loss and duration of hospitalization. Ultrasound guided PNL can be performed in large pelvic stones and sufficient expansion of renal cavities, thus reducing radiation exposure of patients and medical staff.

  1. General Ultrasound Imaging

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  2. Venous Ultrasound (Extremities)

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  3. Carotid Ultrasound Imaging

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  4. Breast ultrasound.

    PubMed

    Ueno, E

    1996-03-01

    In ultrasound, ultrasonic images are formed by means of echoes among tissues with different acoustic impedance. Acoustic impedance is the product of sound speed and bulk modulus. The bulk modulus expresses the elasticity of an object, and in the human body, the value is increased by conditions such as fibrosis and calcification. The sound speed is usually high in elastic tissues and low in water. In the body, it is lowest in the fatty tissue. Ultrasound echoes are strong on the surface of bones which are hard and have a high sound speed. In organs filled with air such as the lungs, the bulk modulus is low and the sound speed is extremely low at 340 m/s, which produce strong echoes (the sound speed in solid tissues is 1,530 m/s). Human tissue is constructed of units smaller than the ultrasonic beam, and it is necessary to understand back-scattering in order to understand the ultrasonic images of these tissues. When ultrasound passes through tissue, it is absorbed as thermal energy and attenuated. Fiber is a tissue with a high absorption and attenuation rate. When the rate increases, the posterior echoes are attenuated. However, in masses with a high water content such as cysts, the posterior echoes are accentuated. This phenomenon is an important, basic finding for determining the properties of tumors. Breast cancer can be classified into two types: stellate carcinoma and circumscribed carcinoma. Since stellate carcinoma is rich in fiber, the posterior echoes are attenuated or lacking. However, circumscribed carcinoma has a high cellularity and the posterior echoes are accentuated. The same tendency is also seen in benign tumors. In immature fibroadenomas, posterior echoes are accentuated, while in fibroadenomas with hyalinosis, the posterior echoes are attenuated. Therefore, if the fundamentals of this tissue characterization and the histological features are understood, reading of ultrasound becomes easy. Color Doppler has also been developed and has contributed

  5. Eye and orbit ultrasound

    MedlinePlus

    Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography ... ophthalmology department of a hospital or clinic. Your eye is numbed with medicine (anesthetic drops). The ultrasound ...

  6. Ultrasound Fracture Diagnosis in Space

    NASA Technical Reports Server (NTRS)

    Dulchavsky, Scott A.; Amponsah, David; Sargsyan, Ashot E.; Garcia, Kathleen M.; Hamilton, Douglas R.; vanHolsbeeck, Marnix

    2010-01-01

    Introduction: This ground-based investigation accumulated high-level clinical evidence on the sensitivity and specificity of point of care ultrasound performed by expert and novice users for the rapid diagnosis of musculoskeletal (MSK) injuries. We developed preliminary educational methodologies to provide just-in-time training of novice users by creating multi-media training tools and imaging procedures for non expert operators and evaluated the sensitivity and specificity of non-expert performed musculoskeletal ultrasound to diagnose acute injuries in a Level 1 Trauma Center. Methods: Patients with potential MSK injuries were identified in the emergency room. A focused MSK ultrasound was performed by expert operators and compared to standard radiographs. A repeat examination was performed by non-expert operators who received a short, just-in-time multimedia education aid. The sensitivity and specificity of the expert and novice ultrasound examinations were compared to gold standard radiography. Results: Over 800 patients were enrolled in this study. The sensitivity and specificity of expert performed ultrasound exceeded 98% for MSK injuries. Novice operators achieved 97% sensitivity and 99% specificity for targeted examinations with the greatest error in fractures involving the hand and foot. Conclusion: Point of care ultrasound is a sensitive and specific diagnostic test for MSK injury when performed by experts and just-in-time trained novice operators.

  7. Towards Dynamic Contrast Specific Ultrasound Tomography

    NASA Astrophysics Data System (ADS)

    Demi, Libertario; van Sloun, Ruud J. G.; Wijkstra, Hessel; Mischi, Massimo

    2016-10-01

    We report on the first study demonstrating the ability of a recently-developed, contrast-enhanced, ultrasound imaging method, referred to as cumulative phase delay imaging (CPDI), to image and quantify ultrasound contrast agent (UCA) kinetics. Unlike standard ultrasound tomography, which exploits changes in speed of sound and attenuation, CPDI is based on a marker specific to UCAs, thus enabling dynamic contrast-specific ultrasound tomography (DCS-UST). For breast imaging, DCS-UST will lead to a more practical, faster, and less operator-dependent imaging procedure compared to standard echo-contrast, while preserving accurate imaging of contrast kinetics. Moreover, a linear relation between CPD values and ultrasound second-harmonic intensity was measured (coefficient of determination = 0.87). DCS-UST can find clinical applications as a diagnostic method for breast cancer localization, adding important features to multi-parametric ultrasound tomography of the breast.

  8. Towards Dynamic Contrast Specific Ultrasound Tomography

    PubMed Central

    Demi, Libertario; Van Sloun, Ruud J. G.; Wijkstra, Hessel; Mischi, Massimo

    2016-01-01

    We report on the first study demonstrating the ability of a recently-developed, contrast-enhanced, ultrasound imaging method, referred to as cumulative phase delay imaging (CPDI), to image and quantify ultrasound contrast agent (UCA) kinetics. Unlike standard ultrasound tomography, which exploits changes in speed of sound and attenuation, CPDI is based on a marker specific to UCAs, thus enabling dynamic contrast-specific ultrasound tomography (DCS-UST). For breast imaging, DCS-UST will lead to a more practical, faster, and less operator-dependent imaging procedure compared to standard echo-contrast, while preserving accurate imaging of contrast kinetics. Moreover, a linear relation between CPD values and ultrasound second-harmonic intensity was measured (coefficient of determination = 0.87). DCS-UST can find clinical applications as a diagnostic method for breast cancer localization, adding important features to multi-parametric ultrasound tomography of the breast. PMID:27703251

  9. Validation of an ultrasound-guided technique to establish a liver-to-coelom ratio and a comparative analysis of the ratios among acclimated and recently wild-caught southern stingrays, Dasyatis americana.

    PubMed

    Grant, Krystan R; Campbell, Terry W; Silver, Tawni I; Olea-Popelka, Francisco J

    2013-01-01

    Southern stingrays, Dasyatis americana, are a well-represented elasmobranch species in public aquaria and other facilities throughout the world. This study was conducted at a facility that experienced some mortality and replenished the collection with wild-caught stingrays. A common necropsy finding among the stingrays was a small, dark liver. The objectives of this study were to assess the reliability of an ultrasound-guided technique for establishing a liver-to-coelom ratio by calculating the approximate length of the liver with respect to the coelomic cavity length and then to compare ratios between acclimated captive and wild-caught stingrays. The ultrasound validation phase of the study measured the distance from the caudal margin of the liver to the pelvic cartilaginous girdle and compared it to the actual distance measured during the necropsy or surgery. There was no significant difference found between the ultrasound and actual distance measurements (P = 0.945). This technique was then used to establish liver-to-coelom ratios and compare two groups of stingrays, presumably under different metabolic states at different periods. Liver-to-coelom ratios were established during initial examinations as well as 8 months after cohabitation in a touch pool exhibit. There were significant differences in liver-to-coelom ratios between the two stingray groups at introduction (median difference = 30.9%, P = 0.007) and after 8 months (median difference = 20.5%, P = 0.008). There were also significant differences in the liver-to-coelom ratios within each group at introduction and at 8 months (acclimated group median difference = 20.4%, P = 0.018; wild-caught group median difference 31%, P = 0.008).

  10. Ultrasound and Therapy

    NASA Astrophysics Data System (ADS)

    Lafon, Cyril

    This paper begins with an overview and a description of the interactions between ultrasound and biological tissues encountered during treatment protocols. In a second part of this seminar, two clinical applications of therapeutic ultrasound will be described in details: -Kidney stone destruction by ultrasound (lithotripsy) and High Intensity Focused Ultrasound for treating prostate cancer (HIFU).

  11. [Ultrasound in emergency medicine].

    PubMed

    Lapostolle, F; Deltour, S; Petrovic, T

    2015-12-01

    Ultrasound has revolutionized the practice of emergency medicine, particularly in prehospital setting. About a patient with dyspnea, we present the role of ultrasound in the diagnosis and emergency treatment. Echocardiography, but also hemodynamic ultrasound (vena cava) and lung exam are valuable tools. Achieving lung ultrasound and diagnostic value of B lines B are detailed.

  12. Ultrasound annual, 1986

    SciTech Connect

    Sanders, R.C.; Hill, M.C.

    1986-01-01

    This book provides an analyses of developments in the field of diagnostic ultrasound. Endoscopic ultrasound and ultrasound-guided aspiration of ovarian follicles for in vitro fertilization are addressed. The use of Doppler ultrasound to measure blood flow in obstetrics is also examined.

  13. Ultrasound in Space Medicine

    NASA Technical Reports Server (NTRS)

    Dulchavsky, Scott A.; Sargsyan, A.E.

    2009-01-01

    This slide presentation reviews the use of ultrasound as a diagnostic tool in microgravity environments. The goals of research in ultrasound usage in space environments are: (1) Determine accuracy of ultrasound in novel clinical conditions. (2) Determine optimal training methodologies, (3) Determine microgravity associated changes and (4) Develop intuitive ultrasound catalog to enhance autonomous medical care. Also uses of Ultrasound technology in terrestrial applications are reviewed.

  14. Ultrasound Imaging for Analyzing Lateral Tongue Movements during Mastication in Adults with Cerebral Palsy Compared with Adults without Oral Motor Disabilities.

    PubMed

    Remijn, Lianne; Weijers, Gert; Nijhuis-van der Sanden, Maria W G; Groen, Brenda E; de Korte, Chris L

    2015-06-01

    Described here is an ultrasound technique used to study tongue movements, particularly lateral tongue movements, during mastication. A method to analyze spatial and temporal tongue movements was developed, and the feasibility of using this method was evaluated. Biplane ultrasound images of tongue movements of four adults without oral motor disability and two adults with oral motor disability as a result of cerebral palsy, were acquired. Tongue movements were analyzed in the coronal and sagittal planes using B-mode and M-mode ultrasonography. Inter-rater and intra-rater agreement for manual tracing of tongue contours was good (ICC = 0.81 and 0.84, respectively). There were significant differences between the two adult groups in movement frequency in the horizontal direction in both coronal and sagittal planes. In the coronal plane, differences in movement frequency and range of vertical movement were detected. Data obtained from sagittal images, with the exception of vertical frequency, indicated no differences between the groups. The protocol developed in this study (using B-mode and M-mode) proved to be valid and reliable. By using this protocol with individuals with and without oral motor disability, we were able to illustrate the clinical application of our protocol to evaluation of differences in tongue movements during mastication.

  15. Case Study Using Ultrasound to Treat /[turned r]/

    ERIC Educational Resources Information Center

    Modha, Geetanjalee; Bernhardt, B. May; Church, Robyn; Bacsfalvi, Penelope

    2008-01-01

    Background: Ultrasound has shown promise as visual feedback in remediation of /[turned r]/.Aims: To compare treatment for [turned r] with and without ultrasound.Methods & Procedures: A Canadian English-speaking adolescent participated in a case study with a no treatment baseline, alternating treatment blocks with and without ultrasound and a…

  16. Prostate Focused Ultrasound Therapy.

    PubMed

    Chapelon, Jean-Yves; Rouvière, Olivier; Crouzet, Sébastien; Gelet, Albert

    2016-01-01

    The tremendous progress in engineering and computing power coupled with ultrasound transducer technology and imaging modalities over the past 20 years have encouraged a revival of clinical interest in ultrasound therapy, mainly in High-Intensity Focused Ultrasound (HIFU). So far, the most extensive results from HIFU obtained in urology involve transrectal prostate ablation, which appears to be an effective therapeutic alternative for patients with malignant prostate tumors. Prostate cancer (PCa) is one of the most frequently diagnosed cancers in men. Several treatment options with different therapeutic approaches exist, including HIFU for localized PCa that has been in use for over 15 years. Since the early 2000s, two systems have been marketed for this application, and other devices are currently in clinical trials. HIFU treatment can be used either alone or in combination with (before- or after-) external beam radiotherapy (EBRT) (before or after HIFU) and can be repeated multiple times. HIFU treatment is performed under real-time monitoring with ultrasound or guided by MRI. Two indications are validated today: Primary care treatment and EBRT failure. The results of HIFU for primary care treatment are similar to standard conformal EBRT, even though no randomized comparative studies have been performed and no 10-year follow up data is yet available for HIFU. Salvage HIFU after EBRT failure is increasing with oncological outcomes, similar to those achieved with surgery but with the advantage of fewer adverse effects. HIFU is an evolving technology perfectly adapted for focal treatment. Thus, HIFU focal therapy is another pathway that must be explored when considering the accuracy and reliability for PCa mapping techniques. HIFU would be particularly suited for such a therapy since it is clear that HIFU outcomes and toxicity are relative to the volume of prostate treated.

  17. High definition ultrasound imaging for battlefield medical applications

    SciTech Connect

    Kwok, K.S.; Morimoto, A.K.; Kozlowski, D.M.; Krumm, J.C.; Dickey, F.M.; Rogers, B; Walsh, N.

    1996-06-23

    A team has developed an improved resolution ultrasound system for low cost diagnostics. This paper describes the development of an ultrasound based imaging system capable of generating 3D images showing surface and subsurface tissue and bone structures. We include results of a comparative study between images obtained from X-Ray Computed Tomography (CT) and ultrasound. We found that the quality of ultrasound images compares favorably with those from CT. Volumetric and surface data extracted from these images were within 7% of the range between ultrasound and CT scans. We also include images of porcine abdominal scans from two different sets of animal trials.

  18. Ultrasound of the Thyroid Gland

    MedlinePlus

    ... Index A-Z Ultrasound - Thyroid Thyroid ultrasound uses sound waves to produce pictures of the thyroid gland ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  19. Ultrasound Annual, 1983

    SciTech Connect

    Sanders, R.C.; Hill, M.C.

    1983-01-01

    The 1983 edition of Ultrasound Annual features a state-of-the-art assessment of real-time ultrasound technology and a look at improvements in real-time equipment. Chapters discuss important new obstetric applications of ultrasound in measuring fetal umbilical vein blood flow and monitoring ovarian follicular development in vivo and in vitro fertilization. Other topics covered include transrectal prostate ultrasound using a linear array system; ultrasound of the common bile duct; ultrasound in tropical diseases; prenatal diagnosis of craniospinal anomalies; scrotal ultrasonography; opthalmic ultrasonography; and sonography of the upper abdominal venous system.

  20. Clinical ultrasound physics.

    PubMed

    Abu-Zidan, Fikri M; Hefny, Ashraf F; Corr, Peter

    2011-10-01

    Understanding the basic physics of ultrasound is essential for acute care physicians. Medical ultrasound machines generate and receive ultrasound waves. Brightness mode (B mode) is the basic mode that is usually used. Ultrasound waves are emitted from piezoelectric crystals of the ultrasound transducer. Depending on the acoustic impedance of different materials, which depends on their density, different grades of white and black images are produced. There are different methods that can control the quality of ultrasound waves including timing of ultrasound wave emission, frequency of waves, and size and curvature of the surface of the transducer. The received ultrasound signal can be amplified by increasing the gain. The operator should know sonographic artifacts which may distort the studied structures or even show unreal ones. The most common artifacts include shadow and enhancement artifacts, edge artifact, mirror artifact and reverberation artifact.

  1. Medical Ultrasound Imaging.

    ERIC Educational Resources Information Center

    Hughes, Stephen

    2001-01-01

    Explains the basic principles of ultrasound using everyday physics. Topics include the generation of ultrasound, basic interactions with material, and the measurement of blood flow using the Doppler effect. (Author/MM)

  2. Transvaginal ultrasound (image)

    MedlinePlus

    Transvaginal ultrasound is a method of imaging the genital tract in females. A hand held probe is inserted directly ... vaginal cavity to scan the pelvic structures, while ultrasound pictures are viewed on a monitor. The test ...

  3. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  4. Prenatal ultrasound - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100197.htm Prenatal ultrasound - series—Procedure, part 1 To use the sharing ... Editorial team. Related MedlinePlus Health Topics Prenatal Testing Ultrasound A.D.A.M., Inc. is accredited by ...

  5. Ultrasound Imaging System Video

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In this video, astronaut Peggy Whitson uses the Human Research Facility (HRF) Ultrasound Imaging System in the Destiny Laboratory of the International Space Station (ISS) to image her own heart. The Ultrasound Imaging System provides three-dimension image enlargement of the heart and other organs, muscles, and blood vessels. It is capable of high resolution imaging in a wide range of applications, both research and diagnostic, such as Echocardiography (ultrasound of the heart), abdominal, vascular, gynecological, muscle, tendon, and transcranial ultrasound.

  6. Synthetic aperture imaging in ultrasound calibration

    NASA Astrophysics Data System (ADS)

    Ameri, Golafsoun; Baxter, John S. H.; McLeod, A. Jonathan; Jayaranthe, Uditha L.; Chen, Elvis C. S.; Peters, Terry M.

    2014-03-01

    Ultrasound calibration allows for ultrasound images to be incorporated into a variety of interventional applica­ tions. Traditional Z- bar calibration procedures rely on wired phantoms with an a priori known geometry. The line fiducials produce small, localized echoes which are then segmented from an array of ultrasound images from different tracked probe positions. In conventional B-mode ultrasound, the wires at greater depths appear blurred and are difficult to segment accurately, limiting the accuracy of ultrasound calibration. This paper presents a novel ultrasound calibration procedure that takes advantage of synthetic aperture imaging to reconstruct high resolution ultrasound images at arbitrary depths. In these images, line fiducials are much more readily and accu­ rately segmented, leading to decreased calibration error. The proposed calibration technique is compared to one based on B-mode ultrasound. The fiducial localization error was improved from 0.21mm in conventional B-mode images to 0.15mm in synthetic aperture images corresponding to an improvement of 29%. This resulted in an overall reduction of calibration error from a target registration error of 2.00mm to 1.78mm, an improvement of 11%. Synthetic aperture images display greatly improved segmentation capabilities due to their improved resolution and interpretability resulting in improved calibration.

  7. Endobronchial ultrasound.

    PubMed

    Falcone, Franco; Fois, Flavio; Grosso, Daniele

    2003-01-01

    Complex technical problems interfered with the application of thoracic ultrasound (US) for studies and clinical research. Moreover, in contrast to radiologists, cardiologists, gastroenterologists, internists, obstetricians, gynecologists and others, pulmonologists were not trained in the basics of US images. However, endoscopic US methods were developed in the last 20 years and these methods also provided important results for pulmonologists. As soon as the technical problems interfering with US application in air-containing spaces were solved, endobronchial US (EBUS) became a valuable technique as well. With EBUS, the delicate multilayer structure of the tracheobronchial wall can be analyzed. This knowledge became decisive for the management of early cancer in the central airways. These lesions can undergo local treatment instead of surgical intervention if the bronchial cartilage is intact and if the adjacent lymph nodes are not involved. EBUS proved valuable as well for the staging of more advanced lung cancer, especially with regard to endoluminal, intramural and extraluminal tumor spread. Endobronchial endosonographers are able to diagnose mediastinal lymph nodes similar to the experience of gastrointestinal endosonographers. EBUS-guided transbronchial needle aspiration (TBNA) improved the results of N-staging of lung cancer, especially in difficult lymph node levels without any clear endoscopic landmarks. The possibility of identifying N2 and N3 stages by means of a nonsurgical procedure can modify the management of lung cancer and decrease the number of unnecessary surgical interventions. EBUS can reduce the need for more invasive procedures such as thoracoscopy or mediastinoscopy. It is also useful for biopsying peripheral lesions or solitary pulmonary nodules instead of fluoroscopic guidance and also plays an important role in the strategy of interventional endoscopy.

  8. Toward image analysis and decision support for ultrasound technology.

    PubMed

    Crofts, Gillian; Padman, Rema; Maharaja, Nisha

    2013-01-01

    Ultrasound is a low cost and efficient method of detecting diseases and abnormalities in the body. Yet there is a lack of precision and reliability associated with the technology, partly due to the operator dependent nature of ultrasound scanning. When scanning is performed to an agreed protocol, ultrasound has been shown to be highly reliable. This research aims to minimize these limitations that arise during ultrasound training, scanning and reporting by developing and evaluating an image analysis and decision support system that can aid the decision making process. We hypothesize that this intervention will likely increase the role of ultrasound in diagnosis when compared with other imaging technologies, particularly in low resource settings.

  9. High-Accuracy Ultrasound Contrast Agent Detection Method for Diagnostic Ultrasound Imaging Systems.

    PubMed

    Ito, Koichi; Noro, Kazumasa; Yanagisawa, Yukari; Sakamoto, Maya; Mori, Shiro; Shiga, Kiyoto; Kodama, Tetsuya; Aoki, Takafumi

    2015-12-01

    An accurate method for detecting contrast agents using diagnostic ultrasound imaging systems is proposed. Contrast agents, such as microbubbles, passing through a blood vessel during ultrasound imaging are detected as blinking signals in the temporal axis, because their intensity value is constantly in motion. Ultrasound contrast agents are detected by evaluating the intensity variation of a pixel in the temporal axis. Conventional methods are based on simple subtraction of ultrasound images to detect ultrasound contrast agents. Even if the subject moves only slightly, a conventional detection method will introduce significant error. In contrast, the proposed technique employs spatiotemporal analysis of the pixel intensity variation over several frames. Experiments visualizing blood vessels in the mouse tail illustrated that the proposed method performs efficiently compared with conventional approaches. We also report that the new technique is useful for observing temporal changes in microvessel density in subiliac lymph nodes containing tumors. The results are compared with those of contrast-enhanced computed tomography.

  10. Aesthetic ultrasound therapy

    NASA Astrophysics Data System (ADS)

    Barthe, Peter G.; Slayton, Michael H.

    2012-10-01

    Ultrasound provides key benefits in aesthetic surgery compared to laser and RF based energy sources. We present results of research, development, pre-clinical and clinical studies, regulatory clearance and commercialization of a revolutionary non-invasive aesthetic ultrasound imaging and therapy system. Clinical applications for this platform include non-invasive face-lifts, brow-lifts, and neck-lifts achieved through fractionated treatment of the superficial musculoaponeurotic system (SMAS) and subcutaneous tissue. Treatment consists of placing a grid of micro-coagulative lesions on the order of 1 mm3 at depths in skin of 1 to 6 mm, source energy levels of 0.1 to 3 J, and spacing on the order of 1.5 mm, from 4 to 10 MHz dual-mode image/treat transducers. System details are described, as well as a regulatory pathway consisting of acoustic and bioheat simulations, source characterization (hydrophone, radiation force, and Schlieren), pre-clinical studies (porcine skin ex vivo, in vivo, and human cadaver), human safety studies (treat and resect) and efficacy trials which culminated in FDA clearance (2009) under a new device classification and world-wide usage. Clinical before and after photographs are presented which validate the clinical approach.

  11. Impact of ultrasound video transfer on the practice of ultrasound

    NASA Astrophysics Data System (ADS)

    Duerinckx, Andre J.; Hayrapetian, Alek S.; Grant, Edward G.; Valentino, Daniel J.; Rahbar, Darius; Kiszonas, Mike; Franco, Ricky; Melany, Michelle; Narin, Sherelle L.; Ragavendra, Nagesh

    1996-05-01

    Sonography can be highly dependent on real-time imaging and as such is highly physician intensive. Such situations arise mostly during complicated ultrasound radiology studies or echocardiology examinations. Under those circumstances it would be of benefit to transmit real-time images beyond the immediate area of the ultrasound laboratory when a physician is not on location. We undertook this study to determine if both static and dynamic image transfer to remote locations might be accomplished using an ultrafast ATM network and PACS. Image management of the local image files was performed by a commercial PACS from AGFA corporation. The local network was Ethernet based, and the global network was based on Asynchronous Transfer Mode (ATM, rates up to 100 Mbits/sec). Real-time image transfer involved two teaching hospitals, one of which had 2 separate ultrasound facilities. Radiologists consulted with technologists via telephone while the examinations were being performed. The applications of ATM network providing real time video for ultrasound imaging in a clinical environment and its potential impact on health delivery and clinical teaching. This technology increased technologist and physician productivity due to the elimination of commute time for physicians and waiting time for technologists and patients. Physician confidence in diagnosis increased compared to reviewing static images alone. This system provided instant access for radiologists to real-time scans from remote sites. Image quality and frame rate were equivalent to the original. The system increased productivity by allowing physicians to monitor studies at multiple sites simultaneously.

  12. Ultrasound-assisted temperature-controlled ionic-liquid dispersive liquid-phase microextraction method for simultaneous determination of anethole, estragole, and para-anisaldehyde in different plant extracts and human urine: a comparative study.

    PubMed

    Rajabi, Maryam; Haji-Esfandiari, Sudabeh; Barfi, Behruz; Ghanbari, Hanieh

    2014-07-01

    In this study, the performances of four ionic-liquid-based microextraction methods, ionic-liquid-based dispersive liquid-liquid microextraction (IL-DLLME), ionic-liquid-based ultrasound-assisted emulsification microextraction (IL-USA-ME), temperature-controlled ionic-liquid dispersive liquid-phase microextraction (TC-IL-DLME), and ultrasound-assisted temperature-controlled ionic-liquid dispersive liquid-phase microextraction (USA-TC-IL-DLME), were investigated for extraction of three bioactive compounds (anethole, estragole, and anisaldehyde) from different plant extracts and human urine. Anethole and estragole were chosen because they can alter cellular processes positively or negatively, and an efficient method is needed for their extraction and sensitive determination in the samples mentioned. Because there is no previous report on the separation of anethole and estragole (structural isomers), first, simultaneous gradient elution and flow programming were used. The microextraction methods were then applied and compared for analysis of these compounds in plant extracts and human urine by use of high-performance liquid chromatography (HPLC). The effect of conditions on extraction efficiency was studied and under the optimum conditions, the best enrichment factors (58-64), limits of detection (14-18 ng mL(-1)), limits of quantification (47-60 ng mL(-1)), and recovery (94.4-101.7 %) were obtained by use of USA-TC-IL-DLME. The optimized conditions were used to determine anethole, estragole, and para-anisaldehyde in fennel, anise, and tarragon extracts and in human urine.

  13. Accelerated heavy ions and the lens. IV. Biomicroscopic and cytopathological analyses of the lenses of mice irradiated with 600 MeV/amu sup 56 Fe ions

    SciTech Connect

    Worgul, B.V.; Medvedovsky, C.; Powers-Risius, P.; Alpen, E. )

    1989-11-01

    The lenses of mice exposed to 600 MeV/amu iron ions were evaluated by slit-lamp biomicroscopy and cytopathological analyses. The doses ranged from 0.05 to 1.6 Gy, and the lenses were assessed at several intervals postirradiation. Cataract, the development of which is dependent on both time and dose, is significantly more advanced in all of the exposed mice when compared to the unirradiated controls. The great difference between the severity of the cataracts caused by 0.05 Gy (the lowest dose used) and those that developed spontaneously in the control animals is an indication that 0.05 Gy may far exceed the threshold dose for the production of cataracts by accelerated iron ions. Cytopathologically, a similar dose dependence was observed for a number of end points including micronucleation, interphase death, and meridional row disorganization. In addition the exposure to the 56Fe ions produced a long-term effect on the mitotic population and a pronounced focal loss of epithelial cytoarchitecture. The microscopic changes support the view that the mechanism of heavy-ion-induced cataractogenesis is the same as that for cataracts caused by low-LET radiation.

  14. [Ultrasound in pediatric dermatology].

    PubMed

    García-Martínez, F J; Muñoz-Garza, F Z; Hernández-Martín, A

    2015-11-01

    Cutaneous ultrasound is particularly useful in pediatric dermatology to diagnose numerous diseases without the need to use invasive tests. The present articles reviews some frequent dermatological entities in children whose study can be simplified through cutaneous ultrasound. This article also provides practical recommendations reported in the literature that may facilitate ultrasound examination, with special mention of benign tumoural disease, both congenital and acquired, and vascular anomalies.

  15. Children's (Pediatric) Abdominal Ultrasound Imaging

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  16. Ultrasound of the Thyroid Gland

    MedlinePlus

    ... waves. Ultrasound imaging, also called ultrasound scanning or sonography , involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the ...

  17. Intravascular ultrasound imaging

    SciTech Connect

    Cavaye, D.M.; White, R.A. )

    1992-01-01

    This book will give vascular surgeons, cardiologists, radiologists, and technologists a complete working knowledge of intravascular ultrasound imaging and the crucial role of this new technology in endovascular diagnosis and therapy. The book reviews the essential principles of vascular pathology and ultrasound imaging and then provides state-of-the-art information on intraluminal ultrasound imaging devices and techniques, including practical guidelines for using catheters, optimizing image quality, and avoiding artifacts. Image interpretation and computerized image reconstruction are also discussed in detail. The first section explains the diagnostic, therapeutic, and experimental applications of intravascular ultrasound, particularly as a adjunct to angioplasty and other current interventional procedures.

  18. An ultrasound speckle tracking (two-dimensional strain) analysis of myocardial deformation in professional soccer players compared with healthy subjects and hypertrophic cardiomyopathy.

    PubMed

    Richand, Viviane; Lafitte, Stéphane; Reant, Patricia; Serri, Karim; Lafitte, Marianne; Brette, Stephanie; Kerouani, Akem; Chalabi, Hakim; Dos Santos, Pierre; Douard, Herve; Roudaut, Raymond

    2007-07-01

    Deformation analysis using 2-dimensional strain echocardiography can detect early systolic function abnormalities in patients with left ventricular hypertrophy. This study was designed to characterize global and regional myocardial deformation using 2-dimensional strain in professional soccer players (PSPs) compared with control subjects and patients with hypertrophic cardiomyopathy (HC). Twenty nine PSPs, 26 patients with HC, and 17 controls were investigated at rest using transthoracic echocardiography with 2-dimensional strain analysis. Radial and transverse strains were significantly higher in PSPs compared with controls, whereas longitudinal strain was lower. Compared with patients with HC, athletes had higher values for transverse, radial, and circumferential strains. In pathologic hypertrophic segments, longitudinal strain was lower in patients with HC than in PSPs. In conclusion, 2-dimensional strain can identify specific patterns of myocardial deformation in PSPs, controls, and patients with HC. It has the potential to become a routinely used method for the differentiation of athlete's heart and HC.

  19. Ultrasound elastography: principles, techniques, and clinical applications.

    PubMed

    Dewall, Ryan J

    2013-01-01

    Ultrasound elastography is an emerging set of imaging modalities used to image tissue elasticity and are often referred to as virtual palpation. These techniques have proven effective in detecting and assessing many different pathologies, because tissue mechanical changes often correlate with tissue pathological changes. This article reviews the principles of ultrasound elastography, many of the ultrasound-based techniques, and popular clinical applications. Originally, elastography was a technique that imaged tissue strain by comparing pre- and postcompression ultrasound images. However, new techniques have been developed that use different excitation methods such as external vibration or acoustic radiation force. Some techniques track transient phenomena such as shear waves to quantitatively measure tissue elasticity. Clinical use of elastography is increasing, with applications including lesion detection and classification, fibrosis staging, treatment monitoring, vascular imaging, and musculoskeletal applications.

  20. Pocket-sized versus standard ultrasound machines in abdominal imaging.

    PubMed

    Tse, K H; Luk, W H; Lam, M C

    2014-06-01

    The pocket-sized ultrasound machine has emerged as an invaluable tool for quick assessment in emergency and general practice settings. It is suitable for instant and quick assessment in cardiac imaging. However, its applicability in the imaging of other body parts has yet to be established. In this pictorial review, we compared the performance of the pocketsized ultrasound machine against the standard ultrasound machine for its image quality in common abdominal pathology.

  1. Ultrasound assisted biogas production from landfill leachate

    SciTech Connect

    Oz, Nilgün Ayman Yarimtepe, Canan Can

    2014-07-15

    Highlights: • Effect of low frequency ultrasound pretreatment on leachate was investigated. • Three different ultrasound energy inputs (200, 400 and 600 W/l) was applied. • Low-frequency ultrasound treatment increased soluble COD in landfill leachate. • Application of ultrasound to leachate increased biogas production about 40%. • Application of ultrasound to leachate increased total methane production rate about 20%. - Abstract: The aim of this study is to increase biogas production and methane yield from landfill leachate in anaerobic batch reactors by using low frequency ultrasound as a pretreatment step. In the first part of the study, optimum conditions for solubilization of organic matter in leachate samples were investigated using various sonication durations at an ultrasound frequency of 20 kHz. The level of organic matter solubilization during ultrasonic pretreatment experiments was determined by calculating the ratio of soluble chemical oxygen demand (sCOD) to total chemical oxygen demand (tCOD). The sCOD/tCOD ratio was increased from 47% in raw leachate to 63% after 45 min sonication at 600 W/l. Non-parametric Friedman’s test indicated that ultrasonic pretreatment has a significant effect on sCOD parameter for leachate (p < 0.05). In the second part of the study, anaerobic batch reactors were operated for both ultrasonically pretreated and untreated landfill leachate samples in order to assess the effect of sonication on biogas and methane production rate. In anaerobic batch reactor feed with ultrasonically pretreated leachate, 40% more biogas was obtained compared to the control reactor. For statistical analysis, Mann–Whitney U test was performed to compare biogas and methane production rates for raw and pretreated leachate samples and it has been found that ultrasonic pretreatment significantly enhanced biogas and methane production rates from leachate (p < 0.05) in anaerobic batch reactors. The overall results showed that low frequency

  2. Ultrasound for fetal assessment in early pregnancy

    PubMed Central

    Whitworth, Melissa; Bricker, Leanne; Neilson, James P; Dowswell, Therese

    2014-01-01

    Background Diagnostic ultrasound is a sophisticated electronic technology, which utilises pulses of high frequency sound to produce an image. Diagnostic ultrasound examination may be employed in a variety of specific circumstances during pregnancy such as after clinical complications, or where there are concerns about fetal growth. Because adverse outcomes may also occur in pregnancies without clear risk factors, assumptions have been made that routine ultrasound in all pregnancies will prove beneficial by enabling earlier detection and improved management of pregnancy complications. Routine screening may be planned for early pregnancy, late gestation, or both. The focus of this review is routine early pregnancy ultrasound. Objectives To assess whether routine early pregnancy ultrasound for fetal assessment (i.e. its use as a screening technique) influences the diagnosis of fetal malformations, multiple pregnancies, the rate of clinical interventions, and the incidence of adverse fetal outcome when compared with the selective use of early pregnancy ultrasound (for specific indications). Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (September 2009). Selection criteria Published, unpublished, and ongoing randomised controlled trials that compared outcomes in women who experienced routine versus selective early pregnancy ultrasound (i.e. less than 24 weeks’ gestation). We have included quasi-randomised trials. Data collection and analysis Two review authors independently extracted data for each included study. We used the Review Manager software to enter and analyse data. Main results Routine/revealed ultrasound versus selective ultrasound/concealed: 11 trials including 37505 women. Ultrasound for fetal assessment in early pregnancy reduces the failure to detect multiple pregnancy by 24 weeks’ gestation (risk ratio (RR) 0.07, 95% confidence interval (CI) 0.03 to 0.17). Routine scan is associated with a reduction in

  3. Ultrasound skin imaging.

    PubMed

    Alfageme Roldán, F

    2014-12-01

    The interaction of high-frequency ultrasound waves with the skin provides the basis for noninvasive, fast, and accessible diagnostic imaging. This tool is increasingly used in skin cancer and inflammatory conditions as well as in cosmetic dermatology. This article reviews the basic principles of skin ultrasound and its applications in the different areas of dermatology.

  4. Pelvic ultrasound - abdominal

    MedlinePlus

    ... pelvic ultrasound. In: Lumb P, Karakitsos D, eds. Critical Care Ultrasound. Philadelphia, PA: Elsevier Saunders; 2015:chap 43. Review Date 3/4/2016 Updated by: Irina Burd, MD, PhD, Associate Professor of Gynecology and Obstetrics at Johns Hopkins University School of Medicine, Baltimore, ...

  5. Seven-site versus three-site method of body composition using BodyMetrix ultrasound compared to dual-energy X-ray absorptiometry.

    PubMed

    Baranauskas, Marissa N; Johnson, Kelly E; Juvancic-Heltzel, Judith A; Kappler, Rachele M; Richardson, Laura; Jamieson, Scott; Otterstetter, Ronald

    2015-10-22

    Obesity is a steadily growing epidemic affecting all segments of the population including college-aged students. The weight gain that is evidenced amid the transitional stage of college years increases the risks associated with cardiovascular and metabolic diseases. The BodyMetrix® BX-2000 (ULTRA) using a seven-site method has been evaluated against dual-energy X-ray absorptiometry (DXA) for estimation of body composition, which has yielded conflicting results. To date, no studies have compared the three-site method Jackson and Pollock three-site method to DXA.

  6. ULTRASOUND INCREASES THE RATE OF BACTERIAL CELL GROWTH

    PubMed Central

    Pitt, William G.; Ross, S. Aaron

    2006-01-01

    Ultrasound was employed to increase the growth rate of bacterial cells attached to surfaces. Staphylococcus epidermidis, Pseudomonas aeruginosa and Escherichia coli cells adhered to and grew on a polyethylene surface in the presence of ultrasound. It was found that low frequency ultrasound (70 kHz) of low acoustic intensity (<2 W/cm2) increased the growth rate of the cells compared to growth without ultrasound. However, at high intensity levels, cells were partially removed from the surface. Ultrasound also enhanced planktonic growth of S. epidermidis and other planktonic bacteria. It is hypothesized that ultrasound increases the rate of transport of oxygen and nutrients to the cells and increases the rate of transport of waste products away from the cells, thus enhancing their growth. PMID:12790676

  7. A novel de-noising method for B ultrasound images

    NASA Astrophysics Data System (ADS)

    Tian, Da-Yong; Mo, Jia-qing; Yu, Yin-Feng; Lv, Xiao-Yi; Yu, Xiao; Jia, Zhen-Hong

    2015-12-01

    B ultrasound as a kind of ultrasonic imaging, which has become the indispensable diagnosis method in clinical medicine. However, the presence of speckle noise in ultrasound image greatly reduces the image quality and interferes with the accuracy of the diagnosis. Therefore, how to construct a method which can eliminate the speckle noise effectively, and at the same time keep the image details effectively is the research target of the current ultrasonic image de-noising. This paper is intended to remove the inherent speckle noise of B ultrasound image. The novel algorithm proposed is based on both wavelet transformation of B ultrasound images and data fusion of B ultrasound images, with a smaller mean squared error (MSE) and greater signal to noise ratio (SNR) compared with other algorithms. The results of this study can effectively remove speckle noise from B ultrasound images, and can well preserved the details and edge information which will produce better visual effects.

  8. Ultrasound-mediated gastrointestinal drug delivery.

    PubMed

    Schoellhammer, Carl M; Schroeder, Avi; Maa, Ruby; Lauwers, Gregory Yves; Swiston, Albert; Zervas, Michael; Barman, Ross; DiCiccio, Angela M; Brugge, William R; Anderson, Daniel G; Blankschtein, Daniel; Langer, Robert; Traverso, Giovanni

    2015-10-21

    There is a significant clinical need for rapid and efficient delivery of drugs directly to the site of diseased tissues for the treatment of gastrointestinal (GI) pathologies, in particular, Crohn's and ulcerative colitis. However, complex therapeutic molecules cannot easily be delivered through the GI tract because of physiologic and structural barriers. We report the use of ultrasound as a modality for enhanced drug delivery to the GI tract, with an emphasis on rectal delivery. Ultrasound increased the absorption of model therapeutics inulin, hydrocortisone, and mesalamine two- to tenfold in ex vivo tissue, depending on location in the GI tract. In pigs, ultrasound induced transient cavitation with negligible heating, leading to an order of magnitude enhancement in the delivery of mesalamine, as well as successful systemic delivery of a macromolecule, insulin, with the expected hypoglycemic response. In a rodent model of chemically induced acute colitis, the addition of ultrasound to a daily mesalamine enema (compared to enema alone) resulted in superior clinical and histological scores of disease activity. In both animal models, ultrasound treatment was well tolerated and resulted in minimal tissue disruption, and in mice, there was no significant effect on histology, fecal score, or tissue inflammatory cytokine levels. The use of ultrasound to enhance GI drug delivery is safe in animals and could augment the efficacy of GI therapies and broaden the scope of agents that could be delivered locally and systemically through the GI tract for chronic conditions such as inflammatory bowel disease.

  9. Ultrasound-mediated gastrointestinal drug delivery

    PubMed Central

    Schoellhammer, Carl M.; Schroeder, Avi; Maa, Ruby; Lauwers, Gregory Yves; Swiston, Albert; Zervas, Michael; Barman, Ross; DiCiccio, Angela M.; Brugge, William R.; Anderson, Daniel G.; Blankschtein, Daniel; Langer, Robert; Traverso, Giovanni

    2016-01-01

    There is a significant clinical need for rapid and efficient delivery of drugs directly to the site of diseased tissues for the treatment of gastrointestinal (GI) pathologies, in particular, Crohn’s and ulcerative colitis. However, complex therapeutic molecules cannot easily be delivered through the GI tract because of physiologic and structural barriers. We report the use of ultrasound as a modality for enhanced drug delivery to the GI tract, with an emphasis on rectal delivery. Ultrasound increased the absorption of model therapeutics inulin, hydrocortisone, and mesalamine two- to tenfold in ex vivo tissue, depending on location in the GI tract. In pigs, ultrasound induced transient cavitation with negligible heating, leading to an order of magnitude enhancement in the delivery of mesalamine, as well as successful systemic delivery of a macromolecule, insulin, with the expected hypoglycemic response. In a rodent model of chemically induced acute colitis, the addition of ultrasound to a daily mesalamine enema (compared to enema alone) resulted in superior clinical and histological scores of disease activity. In both animal models, ultrasound treatment was well tolerated and resulted in minimal tissue disruption, and in mice, there was no significant effect on histology, fecal score, or tissue inflammatory cytokine levels. The use of ultrasound to enhance GI drug delivery is safe in animals and could augment the efficacy of GI therapies and broaden the scope of agents that could be delivered locally and systemically through the GI tract for chronic conditions such as inflammatory bowel disease. PMID:26491078

  10. Simplified stereo-optical ultrasound plane calibration

    NASA Astrophysics Data System (ADS)

    Hoßbach, Martin; Noll, Matthias; Wesarg, Stefan

    2013-03-01

    Image guided therapy is a natural concept and commonly used in medicine. In anesthesia, a common task is the injection of an anesthetic close to a nerve under freehand ultrasound guidance. Several guidance systems exist using electromagnetic tracking of the ultrasound probe as well as the needle, providing the physician with a precise projection of the needle into the ultrasound image. This, however, requires additional expensive devices. We suggest using optical tracking with miniature cameras attached to a 2D ultrasound probe to achieve a higher acceptance among physicians. The purpose of this paper is to present an intuitive method to calibrate freehand ultrasound needle guidance systems employing a rigid stereo camera system. State of the art methods are based on a complex series of error prone coordinate system transformations which makes them susceptible to error accumulation. By reducing the amount of calibration steps to a single calibration procedure we provide a calibration method that is equivalent, yet not prone to error accumulation. It requires a linear calibration object and is validated on three datasets utilizing di erent calibration objects: a 6mm metal bar and a 1:25mm biopsy needle were used for experiments. Compared to existing calibration methods for freehand ultrasound needle guidance systems, we are able to achieve higher accuracy results while additionally reducing the overall calibration complexity. Ke

  11. Simulating cardiac ultrasound image based on MR diffusion tensor imaging

    PubMed Central

    Qin, Xulei; Wang, Silun; Shen, Ming; Lu, Guolan; Zhang, Xiaodong; Wagner, Mary B.; Fei, Baowei

    2015-01-01

    Purpose: Cardiac ultrasound simulation can have important applications in the design of ultrasound systems, understanding the interaction effect between ultrasound and tissue and setting the ground truth for validating quantification methods. Current ultrasound simulation methods fail to simulate the myocardial intensity anisotropies. New simulation methods are needed in order to simulate realistic ultrasound images of the heart. Methods: The proposed cardiac ultrasound image simulation method is based on diffusion tensor imaging (DTI) data of the heart. The method utilizes both the cardiac geometry and the fiber orientation information to simulate the anisotropic intensities in B-mode ultrasound images. Before the simulation procedure, the geometry and fiber orientations of the heart are obtained from high-resolution structural MRI and DTI data, respectively. The simulation includes two important steps. First, the backscatter coefficients of the point scatterers inside the myocardium are processed according to the fiber orientations using an anisotropic model. Second, the cardiac ultrasound images are simulated with anisotropic myocardial intensities. The proposed method was also compared with two other nonanisotropic intensity methods using 50 B-mode ultrasound image volumes of five different rat hearts. The simulated images were also compared with the ultrasound images of a diseased rat heart in vivo. A new segmental evaluation method is proposed to validate the simulation results. The average relative errors (AREs) of five parameters, i.e., mean intensity, Rayleigh distribution parameter σ, and first, second, and third quartiles, were utilized as the evaluation metrics. The simulated images were quantitatively compared with real ultrasound images in both ex vivo and in vivo experiments. Results: The proposed ultrasound image simulation method can realistically simulate cardiac ultrasound images of the heart using high-resolution MR-DTI data. The AREs of their

  12. Ultrasound in regional anaesthesia.

    PubMed

    Griffin, J; Nicholls, B

    2010-04-01

    Ultrasound guidance is rapidly becoming the gold standard for regional anaesthesia. There is an ever growing weight of evidence, matched with improving technology, to show that the use of ultrasound has significant benefits over conventional techniques, such as nerve stimulation and loss of resistance. The improved safety and efficacy that ultrasound brings to regional anaesthesia will help promote its use and realise the benefits that regional anaesthesia has over general anaesthesia, such as decreased morbidity and mortality, superior postoperative analgesia, cost-effectiveness, decreased postoperative complications and an improved postoperative course. In this review we consider the evidence behind the improved safety and efficacy of ultrasound-guided regional anaesthesia, before discussing its use in pain medicine, paediatrics and in the facilitation of neuraxial blockade. The Achilles' heel of ultrasound-guided regional anaesthesia is that anaesthetists are far more familiar with providing general anaesthesia, which in most cases requires skills that are achieved faster and more reliably. To this ends we go on to provide practical advice on ultrasound-guided techniques and the introduction of ultrasound into a department.

  13. Beating the blues: is there any music in fighting cyanobacteria with ultrasound?

    PubMed

    Lürling, Miquel; Tolman, Yora

    2014-12-01

    The hypothesis that cyanobacteria can be controlled by commercially available ultrasound transducers was tested in laboratory experiments with cultures of the cyanobacteria Anabaena sp., Cylindrospermopsis raciborskii and Microcystis aeruginosa and the green alga Scenedesmus obliquus that were grown in the absence or presence of ultrasound (mix of 20, 28 and 44 kHz). The Scenedesmus experiment also included a treatment with the zooplankton grazer Daphnia magna. Chlorophyll-a and biovolume-based growth of Anabaena was significantly lower in ultrasound exposed cultures than in controls. Particle based growth rates were higher in ultrasound treatments. Filaments were significantly shorter in ultrasound exposed cultures reflecting filament breakage. Photosystem II efficiency was not affected by ultrasound. In Cylindrospermopsis chlorophyll-a based growth rates and photosystem II efficiencies were similar in controls and ultrasound treatments, but biovolume-based growth was significantly lower in ultrasound exposed cultures compared to controls. Despite biovolume growth rates of the filamentous cyanobacteria were reduced in ultrasound treatments compared to controls, growth remained positive implying still a population increase. In Microcystis and Scenedesmus growth rates were similar in controls and ultrasound treatments. Hence, no effect of ultrasound on these phytoplankton species was found. Ultrasound should not be viewed "environmental friendly" as it killed all Daphnia within 15 min, releasing Scenedesmus from grazing control in the cultures. Based on our experiments and critical literature review, we conclude that there is no music in controlling cyanobacteria in situ with the commercially available ultrasound transducers we have tested.

  14. Ultrasound Techniques for Space Applications

    NASA Technical Reports Server (NTRS)

    Rooney, James A.

    1985-01-01

    Ultrasound has proven to be a safe non-invasive technique for imaging organs and measuring cardiovascular function. It has unique advantages for application to problems with man in space including evaluation of cardiovascular function both in serial studies and during critical operations. In addition, specialized instrumentation may be capable of detecting the onset of decompression sickness during EVA activities. A spatial location and three-dimensional reconstruction system is being developed to improve the accuracy and reproducibility for serial comparative ultrasound studies of cardiovascular function. The three-dimensional method permits the acquisition of ultrasonic images from many views that can be recombined into a single reconstruction of the heart or vasculature. In addition to conventional imaging and monitoring systems, it is sometimes necessary or desirable to develop instrumentation for special purposes. One example of this type of development is the design of a pulsed-Doppler system to monitor cerebral blood flow during critical operations such as re-entry. A second example is the design of a swept-frequency ultrasound system for the detection of bubbles in the circulatory system and/or soft tissues as an early indication of the onset of decompression sickness during EVA activities. This system exploits the resonant properties of bubbles and can detect both fundamental and second harmonic emissions from the insonified region.

  15. Ultrasound: Head (For Parents)

    MedlinePlus

    ... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... A radiologist (a doctor who's specially trained in reading and interpreting X-ray and ultrasound images) will ...

  16. Ultrasound: Infant Hip

    MedlinePlus

    ... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... radiologist (a doctor who is specially trained in reading and interpreting X-ray and ultrasound images) will ...

  17. Ultrasound: Abdomen (For Parents)

    MedlinePlus

    ... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... A radiologist (a doctor who's specially trained in reading and interpreting X-ray and ultrasound images) will ...

  18. Ultrasound: Pelvis (For Parents)

    MedlinePlus

    ... KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding ... A radiologist (a doctor who's specially trained in reading and interpreting X-ray, ultrasound, and other imaging ...

  19. Venous Ultrasound (Extremities)

    MedlinePlus

    ... the leg – a condition often referred to as deep vein thrombosis. Ultrasound does not use ionizing radiation ... leg. This condition is often referred to as deep vein thrombosis or DVT. These clots may break ...

  20. Ultrasound: Pelvis (For Parents)

    MedlinePlus

    ... pelvic area and images are recorded on a computer. The black-and-white images show the internal ... the images can be seen clearly on the computer screen. A technician (sonographer) trained in ultrasound imaging ...

  1. Ultrasound: Abdomen (For Parents)

    MedlinePlus

    ... abdominal area and images are recorded on a computer. The black-and-white images show the internal ... the images can be seen clearly on the computer screen. A technician (sonographer) trained in ultrasound imaging ...

  2. Ultrasound: Head (For Parents)

    MedlinePlus

    ... the head and images are recorded on a computer. The black-and-white images show the internal ... the images can be seen clearly on the computer screen. A technician (sonographer) trained in ultrasound imaging ...

  3. Ultrasound: Infant Hip

    MedlinePlus

    ... hip area, and images are recorded on a computer. The black-and-white images show the internal ... the images can be seen clearly on the computer screen. A technician (sonographer) trained in ultrasound imaging ...

  4. Ultrasound in pregnancy (image)

    MedlinePlus

    The ultrasound has become a standard procedure used during pregnancy. It can demonstrate fetal growth and can detect increasing ... abnormalities, hydrocephalus, anencephaly, club feet, and other ... does not produce ionizing radiation and is considered ...

  5. General Ultrasound Imaging

    MedlinePlus Videos and Cool Tools

    ... of the reflected sound waves (called the Doppler effect). A computer collects and processes the sounds and ... standard diagnostic ultrasound , there are no known harmful effects on humans. top of page What are the ...

  6. Ultrasound: Bladder (For Parents)

    MedlinePlus

    ... bladder area and images are recorded on a computer. The black-and-white images show the internal ... the images can be seen clearly on the computer screen. A technician (sonographer) trained in ultrasound imaging ...

  7. Thyroid and parathyroid ultrasound.

    PubMed

    Ghervan, Cristina

    2011-03-01

    Thyroid ultrasound is easy to perform due to the superficial location of the thyroid gland, but appropriate equipment is mandatory with a linear high frequency transducer (7.5 - 12) MHz. Some pathological aspects of the thyroid gland are easily diagnosed by ultrasound, like the enlargement of the thyroid volume (goiter) or the presence of nodules and cysts; while other aspects are more difficult and need more experience (diffuse changes in the structure, echogenicity and vascularization of the parenchyma, differential diagnosis of malignant nodules). Ultrasound has become the diagnostic procedure of choice in guidelines for the management of thyroid nodules; most structural abnormalities of the thyroid need evaluation and monitoring but not intervention. A good knowledge of the normal appearance of the thyroid gland is compulsory for an accurate ultrasound diagnosis.

  8. Breast ultrasound tomography with total-variation regularization

    SciTech Connect

    Huang, Lianjie; Li, Cuiping; Duric, Neb

    2009-01-01

    Breast ultrasound tomography is a rapidly developing imaging modality that has the potential to impact breast cancer screening and diagnosis. A new ultrasound breast imaging device (CURE) with a ring array of transducers has been designed and built at Karmanos Cancer Institute, which acquires both reflection and transmission ultrasound signals. To extract the sound-speed information from the breast data acquired by CURE, we have developed an iterative sound-speed image reconstruction algorithm for breast ultrasound transmission tomography based on total-variation (TV) minimization. We investigate applicability of the TV tomography algorithm using in vivo ultrasound breast data from 61 patients, and compare the results with those obtained using the Tikhonov regularization method. We demonstrate that, compared to the Tikhonov regularization scheme, the TV regularization method significantly improves image quality, resulting in sound-speed tomography images with sharp (preserved) edges of abnormalities and few artifacts.

  9. Ultrasound in trauma.

    PubMed

    Rippey, James C R; Royse, Alistair G

    2009-09-01

    Point-of-care ultrasound is well suited for use in the emergency setting for assessment of the trauma patient. Currently, portable ultrasound machines with high-resolution imaging capability allow trauma patients to be imaged in the pre-hospital setting, emergency departments and operating theatres. In major trauma, ultrasound is used to diagnose life-threatening conditions and to prioritise and guide appropriate interventions. Assessment of the basic haemodynamic state is a very important part of ultrasound use in trauma, but is discussed in more detail elsewhere. Focussed assessment with sonography for Trauma (FAST) rapidly assesses for haemoperitoneum and haemopericardium, and the Extended FAST examination (EFAST) explores for haemothorax, pneumothorax and intravascular filling status. In regional trauma, ultrasound can be used to detect fractures, many vascular injuries, musculoskeletal injuries, testicular injuries and can assess foetal viability in pregnant trauma patients. Ultrasound can also be used at the bedside to guide procedures in trauma, including nerve blocks and vascular access. Importantly, these examinations are being performed by the treating physician in real time, allowing for immediate changes to management of the patient. Controversy remains in determining the best training to ensure competence in this user-dependent imaging modality.

  10. Focused ultrasound in ophthalmology

    PubMed Central

    Silverman, Ronald H

    2016-01-01

    The use of focused ultrasound to obtain diagnostically significant information about the eye goes back to the 1950s. This review describes the historical and technological development of ophthalmic ultrasound and its clinical application and impact. Ultrasound, like light, can be focused, which is crucial for formation of high-resolution, diagnostically useful images. Focused, single-element, mechanically scanned transducers are most common in ophthalmology. Specially designed transducers have been used to generate focused, high-intensity ultrasound that through thermal effects has been used to treat glaucoma (via ciliodestruction), tumors, and other pathologies. Linear and annular transducer arrays offer synthetic focusing in which precise timing of the excitation of independently addressable array elements allows formation of a converging wavefront to create a focus at one or more programmable depths. Most recently, linear array-based plane-wave ultrasound, in which the array emits an unfocused wavefront and focusing is performed solely on received data, has been demonstrated for imaging ocular anatomy and blood flow. While the history of ophthalmic ultrasound extends back over half-a-century, new and powerful technologic advances continue to be made, offering the prospect of novel diagnostic capabilities. PMID:27757007

  11. Focused ultrasound in ophthalmology.

    PubMed

    Silverman, Ronald H

    2016-01-01

    The use of focused ultrasound to obtain diagnostically significant information about the eye goes back to the 1950s. This review describes the historical and technological development of ophthalmic ultrasound and its clinical application and impact. Ultrasound, like light, can be focused, which is crucial for formation of high-resolution, diagnostically useful images. Focused, single-element, mechanically scanned transducers are most common in ophthalmology. Specially designed transducers have been used to generate focused, high-intensity ultrasound that through thermal effects has been used to treat glaucoma (via ciliodestruction), tumors, and other pathologies. Linear and annular transducer arrays offer synthetic focusing in which precise timing of the excitation of independently addressable array elements allows formation of a converging wavefront to create a focus at one or more programmable depths. Most recently, linear array-based plane-wave ultrasound, in which the array emits an unfocused wavefront and focusing is performed solely on received data, has been demonstrated for imaging ocular anatomy and blood flow. While the history of ophthalmic ultrasound extends back over half-a-century, new and powerful technologic advances continue to be made, offering the prospect of novel diagnostic capabilities.

  12. Resonant nonlinear ultrasound spectroscopy

    DOEpatents

    Johnson, Paul A.; TenCate, James A.; Guyer, Robert A.; Van Den Abeele, Koen E. A.

    2001-01-01

    Components with defects are identified from the response to strains applied at acoustic and ultrasound frequencies. The relative resonance frequency shift .vertline..DELTA..function./.function..sub.0.vertline., is determined as a function of applied strain amplitude for an acceptable component, where .function..sub.0 is the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak of a selected mode to determine a reference relationship. Then, the relative resonance frequency shift .vertline..DELTA..function./.function..sub.0 is determined as a function of applied strain for a component under test, where fo .function..sub.0 the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak to determine a quality test relationship. The reference relationship is compared with the quality test relationship to determine the presence of defects in the component under test.

  13. High-resolution imaging with a real-time synthetic aperture ultrasound system: a phantom study

    NASA Astrophysics Data System (ADS)

    Huang, Lianjie; Labyed, Yassin; Simonetti, Francesco; Williamson, Michael; Rosenberg, Robert; Heintz, Philip; Sandoval, Daniel

    2011-03-01

    It is difficult for ultrasound to image small targets such as breast microcalcifications. Synthetic aperture ultrasound imaging has recently developed as a promising tool to improve the capabilities of medical ultrasound. We use two different tissueequivalent phantoms to study the imaging capabilities of a real-time synthetic aperture ultrasound system for imaging small targets. The InnerVision ultrasound system DAS009 is an investigational system for real-time synthetic aperture ultrasound imaging. We use the system to image the two phantoms, and compare the images with those obtained from clinical scanners Acuson Sequoia 512 and Siemens S2000. Our results show that synthetic aperture ultrasound imaging produces images with higher resolution and less image artifacts than Acuson Sequoia 512 and Siemens S2000. In addition, we study the effects of sound speed on synthetic aperture ultrasound imaging and demonstrate that an accurate sound speed is very important for imaging small targets.

  14. Ultrasound dynamic micro-elastography applied to the viscoelastic characterization of soft tissues and arterial walls.

    PubMed

    Schmitt, Cédric; Hadj Henni, Anis; Cloutier, Guy

    2010-09-01

    Quantitative noninvasive methods that provide in vivo assessment of mechanical characterization of living tissues, organs and artery walls are of interest because information on their viscoelastic properties in the presence of disease can affect diagnosis and treatment options. This article proposes the dynamic micro-elastography (DME) method to characterize viscoelasticity of small homogeneous soft tissues, as well as the adaptation of the method for vascular applications [vascular dynamic micro-elastography (VDME)]. The technique is based on the generation of relatively high-frequency (240-1100 Hz) monochromatic or transient plane shear waves within the medium and the tracking of these waves from radio-frequency (RF) echoes acquired at 25 MHz with an ultrasound biomicroscope (Vevo 770, Visualsonics). By employing a dedicated shear wave gated strategy during signal acquisition, postprocessed RF sequences could achieve a very high frame rate (16,000 images per s). The proposed technique successfully reconstructed shear wave displacement maps at very high axial (60 mum) and lateral (250 mum) spatial resolutions for motions as low as a few mum. An inverse problem formulated as a least-square minimization, involving analytical simulations (for homogenous and vascular geometries) and experimental measurements were performed to retrieve storage (G') and loss (G'') moduli as a function of the shearing frequency. Viscoelasticity measurements of agar-gelatin materials and of a small rat liver were proven feasible. Results on a very thin wall (3 mm thickness) mimicking artery enabled to validate the feasibility and the reliability of the vascular inverse problem formulation. Subsequently, the G' and G'' of a porcine aorta showed that both parameters are strongly dependent on frequency, suggesting that the vascular wall is mechanically governed by complex viscoelastic laws.

  15. The ultrasound-assisted aqueous extraction of rice bran oil.

    PubMed

    Khoei, Maryam; Chekin, Fereshteh

    2016-03-01

    In this work, aqueous extraction of rice bran oil was done without and with ultrasound pretreatment. Key factors controlling the extraction and optimal operating conditions were identified. The highest extraction efficiency was found at pH=12, temperature of 45°C, agitation speed of 800rpm and agitation time of 15min, ultrasound treatment time of 70min and ultrasound treatment temperature of 25°C. Moreover, extraction yields were compared to ultrasound-assisted aqueous extraction and Soxhlet extraction. The results showed that the yield of rice bran oil at ultrasound-assisted aqueous extraction was close to the yield of oil extracted by hexane Soxhlet extraction. This result implied that the yield of rice bran oil was significantly influenced by ultrasound. With regard to quality, the oil extracted by ultrasound-assisted aqueous process had a lower content of free fatty acid and lower color imparting components than the hexane-extracted oil. Also, effect of parboiling of paddy on hexane and ultrasound-assisted aqueous extraction was studied. Both extraction methods gives higher percentage of oil from par boiled rice bran compared with raw rice bran. This may be due to the fact that parboiling releases the oil.

  16. Comparing cost-effectiveness between endoscopic ultrasound and endoscopic retrograde cholangiopancreatography in diagnosis of common bile duct stone in patients with predefined risks: A study from a developing country

    PubMed Central

    Netinatsunton, Nisa; Attasaranya, Siriboon; Sottisuporn, Jaksin; Witeerungrot, Teepawit; Jongboonyanuparp, Theeratus; Piratvisuth, Teerha; Ovartlarnporn, Bancha

    2016-01-01

    Background and Objectives: Endoscopic ultrasound (EUS) achieves results comparable to endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of common bile duct (CBD) stone, but studies from the western have shown EUS to be less expensive in patients with intermediate risk for CBD stones. The aim of this study was to compare the costs of EUS and ERCP in the diagnosis of CBD stones in a developing country. Materials and Methods: A prospective study was done with 141 patients with suspected CBD stones, categorized as having high or intermediate risk for CBD stone. All underwent EUS, and the high-risk patients had ERCP after the EUS. For intermediate-risk patients, an ERCP was done at the discretion of the attending physician. The CBD stone was confirmed by ERCP in patients who underwent both EUS and ERCP. Patients who received EUS only were followed up every 3 months for 1 year. The false negative rate in patients with EUS and ERCP was estimated in the clinical follow-up. Result: One hundred and forty-one patients (141: 83 females, 58 males) with a mean age ± standard deviation (SD) of 55.71 ±18.68 years were recruited. Ninety-four (94) patients underwent both EUS and ERCP. ERCP confirmed the diagnosis in 83 of 85 patients (97.6%) with CBD stone detected by EUS. Forty-seven (47) patients with a negative EUS and no ERCP done were symptom-free during the follow-up. The overall sensitivity, specificity, positive predictive value, and negative predictive value of EUS were 97.6%, 80%, 97.6%, and 80% respectively. An EUS-based strategy for high-risk patients was 15% more expensive than an ERCP-based strategy, but the EUS-based strategy reduced the cost to 37.78% less than the ERCP-based strategy in intermediate-risk patients. The EUS-based strategy was cost-saving when the CBD stone prevalence was less than 52.5%. Conclusion: EUS is safer and less costly than ERCP for CBD stone diagnosis in patients with intermediate risk. PMID:27386473

  17. Endoanal ultrasound in perianal fistulae and abscesses.

    PubMed

    Visscher, Arjan Paul; Felt-Bersma, Richelle J F

    2015-06-01

    Endoanal ultrasound is a technique that provides imaging of the anal sphincters and its surrounding structures as well as the pelvic floor. However, endoanal magnetic resonance imaging (MRI) is preferred by most physicians, although costs are higher and demand easily outgrows availability. Endoanal ultrasound is an accurate imaging modality delineating anatomy of both cryptoglandular as well as Crohn perianal fistula and abscess. Endoanal ultrasound is comparable with examination under anesthesia and equally sensitive as endoanal MRI in fistula detection. When fistula tracts or abscesses are located above the puborectal muscle, an additional endoanal MRI should be performed. Preoperative imaging is advocated in recurrent cryptoglandular fistula because a more complex pattern can be expected. Endoanal ultrasound can help avoid missing tracts during surgery, lowering the chance for the fistula to persist or recur. It can easily be performed in an outpatient setting and endosonographic skills are quickly incremented. Costs are low and endoanal ultrasound has the potential to improve outcome of patients with both cryptoglandular and fistulizing Crohn disease; therefore, it values more attention.

  18. Diagnostic Accuracy of Secondary Ultrasound Exam in Blunt Abdominal Trauma

    PubMed Central

    Rajabzadeh Kanafi, Alireza; Giti, Masoumeh; Gharavi, Mohammad Hossein; Alizadeh, Ahmad; Pourghorban, Ramin; Shekarchi, Babak

    2014-01-01

    Background: In stable patients with blunt abdominal trauma, accurate diagnosis of visceral injuries is crucial. Objectives: To determine whether repeating ultrasound exam will increase the sensitivity of focused abdominal sonography for trauma (FAST) through revealing additional free intraperitoneal fluid in patients with blunt abdominal trauma. Patients and Methods: We performed a prospective observational study by performing primary and secondary ultrasound exams in blunt abdominal trauma patients. All ultrasound exams were performed by four radiology residents who had the experience of more than 400 FAST exams. Five routine intraperitoneal spaces as well as the interloop space were examined by ultrasound in order to find free fluid. All patients who expired or were transferred to the operating room before the second exam were excluded from the study. All positive ultrasound results were compared with intra-operative and computed tomography (CT) findings and/or the clinical status of the patients. Results: Primary ultrasound was performed in 372 patients; 61 of them did not undergo secondary ultrasound exam; thus, were excluded from the study.Three hundred eleven patients underwent both primary and secondary ultrasound exams. One hundred and two of all patients were evaluated by contrast enhanced CT scan and 31 underwent laparotomy. The sensitivity of ultrasound exam in detecting intraperitoneal fluid significantly increased from 70.7% for the primary exam to 92.7% for the secondary exam. Examining the interloop space significantly improved the sensitivity of ultrasonography in both primary (from 36.6% to 70.7%) and secondary (from 65.9% to 92.7%) exams. Conclusions: Performing a secondary ultrasound exam in stable blunt abdominal trauma patients and adding interloop space scan to the routine FAST exam significantly increases the sensitivity of ultrasound in detecting intraperitoneal free fluid. PMID:25763079

  19. Experimental and simulation studies on focused ultrasound triggered drug delivery.

    PubMed

    Jin, Zhen; Choi, Yongjin; Ko, Seong Young; Park, Jong-Oh; Park, Sukho

    2017-01-01

    To improve drug delivery efficiency in cancer therapy, many researchers have recently concentrated on drug delivery systems that use anticancer drug loaded micro- or nanoparticles. In addition, induction methods, such as ultrasound, magnetic field, and infrared light, have been considered as active induction methods for drug delivery. Among these, focused ultrasound has been regarded as a promising candidate for the active induction method of drug delivery system because it can penetrate a deep site in soft tissue, and its energy can be focused on the targeted lesion. In this research, we employed focused ultrasound as an active induction method. For an anticancer drug loaded microparticles, we fabricated poly-lactic-co-glycolic acid docetaxel (PLGA-DTX) nanoparticle encapsulated alginate microbeads using the single-emulsion technique and the aeration method. To select the appropriate operating parameter for the focused ultrasound, we measured the pressure and temperature induced by the focused ultrasound at the focal area using a needle-type hydrophone and a digital thermal detector, respectively. Additionally, we conducted a simulation of focused ultrasound using COMSOL Multiphysics 4.3a. The experimental measurement results were compared with the simulation results. In addition, the drug release rates of the PLGA-DTX-encapsulated alginate microbeads induced by the focused ultrasound were tested. Through these experiments, we determined that the appropriate focused ultrasound parameter was peak pressure of 1 MPa, 10 cycle/burst, and burst period of 20 μSec. Finally, we performed the cell cytotoxicity and drug uptake test with focused ultrasound induction and found that the antitumor effect and drug uptake efficiency were significantly enhanced by the focused ultrasound induction. Thus, we confirmed that focused ultrasound can be an effective induction method for an anticancer drug delivery system.

  20. [Crohn disease: diagnosis by graded compression ultrasound].

    PubMed

    Tarján, Z; Makó, E; Dévai, T; Tulassay, Z

    1995-08-27

    Fifty-four patients with suspected Crohn's disease of the small bowel underwent ultrasound examination with graded compression. The pathologic sonographic findings were compared with the clinical, endoscopic and in 32 cases with the parallel performed CT and selective enterographic examinations. Of the 29 proven cases of Crohn's disease 26 (89.7%) had bowel wall thickening detectable with US. The change in the bowel wall structure correlated to the stage of the disease. The luminal narrowing, the mesenteric involvement, the enlargement of the mesenteric lymph nodes, the abscesses and fistulas were judged easily, but the length and the location of the bowel segment were estimated only approximately. The characteristic but nonspecific signs observed by ultrasound were found to be a useful adjunct to the endoscopic and roentgen examinations. The ultrasound with graded compression in our view is a well usable alternative method for both diagnosis and follow-up, informing about the transmural spread of the pathology.

  1. Microbubble ultrasound contrast agents: a review.

    PubMed

    Stride, E; Saffari, N

    2003-01-01

    The superior scattering properties of gas bubbles compared with blood cells have made microbubble ultrasound contrast agents important tools in ultrasound diagnosis. Over the past 2 years they have become the focus of a wide and rapidly expanding field of research, with their benefits being repeatedly demonstrated, both in ultrasound image enhancement, and more recently in drug and gene delivery applications. However, despite considerable investigation, their behaviour is by no means fully understood and, while no definite evidence of harmful effects has been obtained, there remain some concerns as to their safety. In this review the existing theoretical and experimental evidence is examined in order to clarify the extent to which contrast agents are currently understood and to identify areas for future research. In particular the disparity between the conditions considered in theoretical models and those encountered both in vitro, and more importantly in vivo is discussed, together with the controversy regarding the risk of harmful bio-effects.

  2. Ultrasound physics in a nutshell.

    PubMed

    Coltrera, Marc D

    2010-12-01

    This content presents to the neophyte ultrasonographer the essential nutshell of information needed to properly interpret ultrasound images. Basic concepts of physics related to ultrasound are supported with formulas and related to clinical use.

  3. Quo vadis medical ultrasound?

    PubMed

    Lewin, Peter A

    2004-04-01

    The last three decades of development in diagnostic ultrasound imaging and technology are briefly reviewed and the impact of the crucial link between the two apparently independent research efforts, which eventually facilitated implementation of harmonic imaging modality is explored. These two efforts included the experiments with piezoelectric PVDF polymer material and studies of the interaction between ultrasound energy and biological tissue. Harmonic imaging and its subsequent improvements revolutionized the diagnostic power of clinical ultrasound and brought along images of unparalleled resolution, close to that of magnetic resonance imaging (MRI) quality. The nonlinear propagation effects and their implications for both diagnostic and therapeutic applications of ultrasound are also briefly addressed. In diagnostic applications, the impact of these effects on image resolution and tissue characterization is reviewed; in therapeutic applications, the influence of nonlinear propagation effects on highly localized tissue ablation and cauterization is examined. Next, the most likely developments and future trends in clinical ultrasound technology, including 3D and 4D imaging, distant palpation, image enhancement using contrast agents, monitoring, and merger of diagnostic and therapeutic applications by e.g. introducing ultrasonically controlled targeted drug delivery are reviewed. Finally, a possible competition from other imaging modalities is discussed.

  4. Medical ultrasound systems.

    PubMed

    Powers, Jeff; Kremkau, Frederick

    2011-08-06

    Medical ultrasound imaging has advanced dramatically since its introduction only a few decades ago. This paper provides a short historical background, and then briefly describes many of the system features and concepts required in a modern commercial ultrasound system. The topics addressed include array beam formation, steering and focusing; array and matrix transducers; echo image formation; tissue harmonic imaging; speckle reduction through frequency and spatial compounding, and image processing; tissue aberration; Doppler flow detection; and system architectures. It then describes some of the more practical aspects of ultrasound system design necessary to be taken into account for today's marketplace. It finally discusses the recent explosion of portable and handheld devices and their potential to expand the clinical footprint of ultrasound into regions of the world where medical care is practically non-existent. Throughout the article reference is made to ways in which ultrasound imaging has benefited from advances in the commercial electronics industry. It is meant to be an overview of the field as an introduction to other more detailed papers in this special issue.

  5. Diagnostic Emergency Ultrasound: Assessment Techniques In The Pediatric Patient.

    PubMed

    Guttman, Joshua; Nelson, Bret P

    2016-01-01

    Emergency ultrasound is performed at the point of care to answer focused clinical questions in a rapid manner. Over the last 20 years, the use of this technique has grown rapidly, and it has become a core requirement in many emergency medicine residencies and in some pediatric emergency medicine fellowships. The use of emergency ultrasound in the pediatric setting is increasing due to the lack of ionizing radiation with these studies, as compared to computed tomography. Utilizing diagnostic ultrasound in the emergency department can allow clinicians to arrive at a diagnosis at the bedside rather than sending the patient out of the department for another study. This issue focuses on common indications for diagnostic ultrasound, as found in the pediatric literature or extrapolated from adult literature where pediatric evidence is scarce. Limitations, current trends, controversies, and future directions of diagnostic ultrasound in the emergency department are also discussed.

  6. In-flight ultrasound identification of pneumothorax.

    PubMed

    Quick, Jacob A; Uhlich, Rindi M; Ahmad, Salman; Barnes, Stephen L; Coughenour, Jeffrey P

    2016-02-01

    Ultrasound is a standard adjunct to the initial evaluation of injured patients in the emergency department. We sought to evaluate the ability of prehospital, in-flight thoracic ultrasound to identify pneumothorax. Non-physician aeromedical providers were trained to perform and interpret thoracic ultrasound. All adult trauma patients and adult medical patients requiring endotracheal intubation underwent both in-flight and emergency department ultrasound evaluations. Findings were documented independently and reviewed to ensure quality and accuracy. Results were compared to chest X-ray and computed tomography (CT). One hundred forty-nine patients (136 trauma/13 medical) met inclusion criteria. Mean age was 44.4 (18-94) years; 69 % were male. Mean injury severity score was 17.68 (1-75), and mean chest injury score was 2.93 (0-6) in the injured group. Twenty pneumothoraces and one mainstem intubation were identified. Sixteen pneumothoraces were correctly identified in the field. A mainstem intubation was misinterpreted. When compared to chest CT (n = 116), prehospital ultrasound had a sensitivity of 68 % (95 % confidence interval (CI) 46-85 %), a specificity of 96 % (95 % CI 90-98 %), and an overall accuracy of 91 % (95 % CI 85-95 %). In comparison, emergency department (ED) ultrasound had a sensitivity of 84 % (95 % CI 62-94 %), specificity of 98 % (95 % CI 93-99 %), and an accuracy of 96 % (95 % CI 90-98 %). The unique characteristics of the aeromedical environment render the auditory element of a reliable physical exam impractical. Thoracic ultrasonography should be utilized to augment the diagnostic capabilities of prehospital aeromedical providers.

  7. Ultrasound in space

    NASA Technical Reports Server (NTRS)

    Martin, David S.; South, Donna A.; Garcia, Kathleen M.; Arbeille, Philippe

    2003-01-01

    Physiology of the human body in space has been a major concern for space-faring nations since the beginning of the space era. Ultrasound (US) is one of the most cost effective and versatile forms of medical imaging. As such, its use in characterizing microgravity-induced changes in physiology is being realized. In addition to the use of US in related ground-based studies, equipment has also been modified to fly in space. This involves alteration to handle the stresses of launch and different power and cooling requirements. Study protocols also have been altered to accommodate the microgravity environment. Ultrasound studies to date have shown a pattern of adaptation to microgravity that includes changes in cardiac chamber sizes and vertebral spacing. Ultrasound has been and will continue to be an important component in the investigation of physiological and, possibly, pathologic changes occurring in space or as a result of spaceflight.

  8. Ultrasound in analytical chemistry.

    PubMed

    Priego Capote, F; Luque de Castro, M D

    2007-01-01

    Ultrasound is a type of energy which can help analytical chemists in almost all their laboratory tasks, from cleaning to detection. A generic view of the different steps which can be assisted by ultrasound is given here. These steps include preliminary operations usually not considered in most analytical methods (e.g. cleaning, degassing, and atomization), sample preparation being the main area of application. In sample preparation ultrasound is used to assist solid-sample treatment (e.g. digestion, leaching, slurry formation) and liquid-sample preparation (e.g. liquid-liquid extraction, emulsification, homogenization) or to promote heterogeneous sample treatment (e.g. filtration, aggregation, dissolution of solids, crystallization, precipitation, defoaming, degassing). Detection techniques based on use of ultrasonic radiation, the principles on which they are based, responses, and the quantities measured are also discussed.

  9. [Ultrasound and regional anaesthesia].

    PubMed

    Delaunay, L; Plantet, F; Jochum, D

    2009-02-01

    The use of ultrasound is the latest major evolution in regional anaesthesia. Review of available literature shows significant changes in clinical practice. Ultrasound guidance allows the visualization of anatomical variations or unsuspected intraneural injections, reduces the volume of local anaesthetic injections and confirms correct local anaesthetic distribution or catheter placement. No study has found a statistical difference in success rates and safety because all studies were underpowered. However, the ability to visualize an invasive procedure that has been performed blindly in the past is an undeniable progress in terms of safety. The necessity to be familiar with the machine and the learning curve can be repulsive. The aim of this article is to demystify ultrasound guidance by explaining the fundamentals of the clinical use of ultrasound. With the help of different chapters, the authors explain the different adjustments and possible artefacts and give easy solutions for the use of bedside ultrasound. Training is essential and can be performed on manikins or training phantom. For each region the main anatomical landmarks are explained. One must be familiar with several imaging techniques: short axis (transverse) or long axis (longitudinal) nerve imaging, in-plane or out-of-plane imaging and hydrolocalization. Viewing the needle's tip position during its progression remains the main safety endpoint. Therefore, electrical nerve stimulation and ultrasound guidance should be combined, especially for beginners, to confirm proximity to neural structures and to help in case of difficulty. Optimizing safety and clinical results must remain a key priority in regional anaesthesia. Finally, specific regulations concerning the transducers are described. Paediatric specificities are also mentioned.

  10. Xampling in ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Wagner, Noam; Eldar, Yonina C.; Feuer, Arie; Danin, Gilad; Friedman, Zvi

    2011-03-01

    Recent developments of new medical treatment techniques put challenging demands on ultrasound imaging systems in terms of both image quality and raw data size. Traditional sampling methods result in very large amounts of data, thus, increasing demands on processing hardware and limiting the flexibility in the postprocessing stages. In this paper, we apply Compressed Sensing (CS) techniques to analog ultrasound signals, following the recently developed Xampling framework. The result is a system with significantly reduced sampling rates which, in turn, means significantly reduced data size while maintaining the quality of the resulting images.

  11. Cardiac 4D Ultrasound Imaging

    NASA Astrophysics Data System (ADS)

    D'hooge, Jan

    Volumetric cardiac ultrasound imaging has steadily evolved over the last 20 years from an electrocardiography (ECC) gated imaging technique to a true real-time imaging modality. Although the clinical use of echocardiography is still to a large extent based on conventional 2D ultrasound imaging it can be anticipated that the further developments in image quality, data visualization and interaction and image quantification of three-dimensional cardiac ultrasound will gradually make volumetric ultrasound the modality of choice. In this chapter, an overview is given of the technological developments that allow for volumetric imaging of the beating heart by ultrasound.

  12. An autotuning respiration compensation system based on ultrasound image tracking.

    PubMed

    Kuo, Chia-Chun; Chuang, Ho-Chiao; Teng, Kuan-Ting; Hsu, Hsiao-Yu; Tien, Der-Chi; Wu, Chih-Jen; Jeng, Shiu-Chen; Chiou, Jeng-Fong

    2016-11-22

    The purpose of this study was to develop an ultrasound image tracking algorithm (UITA) for extracting the exact displacement of internal organs caused by respiratory motion. The program can track organ displacements in real time, and analyze the displacement signals associated with organ displacements via a respiration compensating system (RCS). The ultrasound imaging system is noninvasive and has a high spatial resolution and a high frame rate (around 32 frames/s), which reduces the radiation doses that patients receive during computed tomography and X-ray observations. This allows for the continuous noninvasive observation and compensation of organ displacements simultaneously during a radiation therapy session.This study designed a UITA for tracking the motion of a specific target, such as the human diaphragm. Simulated diaphragm motion driven by a respiration simulation system was observed with an ultrasound imaging system, and then the induced diaphragm displacements were calculated by our proposed UITA. These signals were used to adjust the gain of the RCS so that the amplitudes of the compensation signals were close to the target movements. The inclination angle of the ultrasound probe with respect to the surface of the abdomen affects the results of ultrasound image displacement tracking. Therefore, the displacement of the phantom was verified by a LINAC with different inclination-angle settings of the ultrasound probe. The experimental results indicate that the best inclination angle of the ultrasound probe is 40 degrees, since this results in the target displacement of the ultrasound images being close to the actual target motion. The displacement signals of the tracking phantom and the opposing displacement signals created by the RCS were compared to assess the positioning accuracy of our proposed ultrasound image tracking technique combined with the RCS.When the ultrasound probe was inclined by 40 degrees in simulated respiration experiments using sine

  13. Ultrasound stylet for non-image-guided ventricular catheterization.

    PubMed

    Coulson, Nathaniel K; Chiarelli, Peter A; Su, David K; Chang, Jason J; MacConaghy, Brian; Murthy, Revathi; Toms, Peter; Robb, Terrence L; Ellenbogen, Richard G; Browd, Samuel R; Mourad, Pierre D

    2015-10-01

    OBJECT Urgent ventriculostomy placement can be a lifesaving procedure in the setting of hydrocephalus or elevated intracranial pressure. While external ventricular drain (EVD) insertion is common, there remains a high rate of suboptimal drain placement. Here, the authors seek to demonstrate the feasibility of an ultrasound-based guidance system that can be inserted into an existing EVD catheter to provide a linear ultrasound trace that guides the user toward the ventricle. METHODS The ultrasound stylet was constructed as a thin metal tube, with dimensions equivalent to standard catheter stylets, bearing a single-element, ceramic ultrasound transducer at the tip. Ultrasound backscatter signals from the porcine ventricle were processed by custom electronics to offer real-time information about ventricular location relative to the catheter. Data collected from the prototype device were compared with reference measurements obtained using standard clinical ultrasound imaging. RESULTS A study of porcine ventricular catheterization using the experimental device yielded a high rate of successful catheter placement after a single pass (10 of 12 trials), despite the small size of pig ventricles and the lack of prior instruction on porcine ventricular architecture. A characteristic double-peak signal was identified, which originated from ultrasound reflections off of the near and far ventricular walls. Ventricular dimensions, as obtained from the width between peaks, were in agreement with standard ultrasound reference measurements (p < 0.05). Furthermore, linear ultrasound backscatter data permitted in situ measurement of the stylet distance to the ventricular wall (p < 0.05), which assisted in catheter guidance. CONCLUSIONS The authors have demonstrated the ability of the prototype ultrasound stylet to guide ventricular access in the porcine brain. The alternative design of the device makes it potentially easy to integrate into the standard workflow for bedside EVD

  14. Calibration and Evaluation of Ultrasound Thermography using Infrared Imaging

    PubMed Central

    Hsiao, Yi-Sing; Deng, Cheri X.

    2015-01-01

    Real-time monitoring of the spatiotemporal evolution of tissue temperature is important to ensure safe and effective treatment in thermal therapies including hyperthermia and thermal ablation. Ultrasound thermography has been proposed as a non-invasive technique for temperature measurement, and accurate calibration of the temperature-dependent ultrasound signal changes against temperature is required. Here we report a method that uses infrared (IR) thermography for calibration and validation of ultrasound thermography. Using phantoms and cardiac tissue specimens subjected to high-intensity focused ultrasound (HIFU) heating, we simultaneously acquired ultrasound and IR imaging data from the same surface plane of a sample. The commonly used echo time shift-based method was chosen to compute ultrasound thermometry. We first correlated the ultrasound echo time shifts with IR-measured temperatures for material-dependent calibration and found that the calibration coefficient was positive for fat-mimicking phantom (1.49 ± 0.27) but negative for tissue-mimicking phantom (− 0.59 ± 0.08) and cardiac tissue (− 0.69 ± 0.18 °C-mm/ns). We then obtained the estimation error of the ultrasound thermometry by comparing against the IR measured temperature and revealed that the error increased with decreased size of the heated region. Consistent with previous findings, the echo time shifts were no longer linearly dependent on temperature beyond 45 – 50 °C in cardiac tissues. Unlike previous studies where thermocouples or water-bath techniques were used to evaluate the performance of ultrasound thermography, our results show that high resolution IR thermography provides a useful tool that can be applied to evaluate and understand the limitations of ultrasound thermography methods. PMID:26547634

  15. Combined photoacoustic and ultrasound biomicroscopy.

    PubMed

    Harrison, Tyler; Ranasinghesagara, Janaka C; Lu, Huihong; Mathewson, Kory; Walsh, Andrew; Zemp, Roger J

    2009-11-23

    We report on the development of an imaging system capable of combined ultrasound and photoacoustic imaging based on a fast-scanning single-element 25-MHz ultrasound transducer and a unique light-delivery system. The system is capable of 20 ultrasound frames per second and slower photoacoustic frame rates limited by laser pulse-repetition rates. Laser and ultrasound pulses are interlaced for co-registration of photoacoustic and ultrasound images. In vivo imaging of a human finger permits ultrasonic visualization of vessel structures and speckle changes indicative of blood flow, while overlaid photoacoustic images highlight some small vessels that are not clear from the ultrasound scan. Photoacoustic images provide optical absorption contrast co-registered in the structural and blood-flow context of ultrasound with high-spatial resolution and may prove important for clinical diagnostics and basic science of the microvasculature.

  16. Recent advances in medical ultrasound

    NASA Astrophysics Data System (ADS)

    Crum, Lawrence

    2014-03-01

    Ultrasound has become one of the most widely used imaging modalities in medicine; yet, before ultrasound-imaging systems became available, high intensity ultrasound was used as early as the 1950s to ablate regions in the brains of human patients. Recently, a variety of novel applications of ultrasound have been developed that include site-specific and ultrasound-mediated drug delivery, acoustocautery, lipoplasty, histotripsy, tissue regeneration, and bloodless surgery, among many others. This lecture will review several new applications of therapeutic ultrasound and address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. We shall particularly emphasize the use of High Intensity Focused Ultrasound (HIFU) in the treatment of benign and malignant tumors.

  17. Ultrasound induced green solvent extraction of oil from oleaginous seeds.

    PubMed

    Sicaire, Anne-Gaëlle; Vian, Maryline Abert; Fine, Frédéric; Carré, Patrick; Tostain, Sylvain; Chemat, Farid

    2016-07-01

    Ultrasound-assisted extraction of rapeseed oil was investigated and compared with conventional extraction for energy efficiency, throughput time, extraction yield, cleanness, processing cost and product quality. A multivariate study enabled us to define optimal parameters (7.7 W/cm(2) for ultrasonic power intensity, 40 °C for processing temperature, and a solid/liquid ratio of 1/15) for ultrasound-assisted extraction of oil from oilseeds to maximize lipid yield while reducing solvent consumption and extraction time using response surface methodology (RSM) with a three-variable central composite design (CCD). A significant difference in oil quality was noted under the conditions of the initial ultrasound extraction, which was later avoided using ultrasound in the absence of oxygen. Three concepts of multistage cross-current extraction were investigated and compared: conventional multistage maceration, ultrasound-assisted maceration and a combination, to assess the positive impact of using ultrasound on the seed oil extraction process. The study concludes that ultrasound-assisted extraction of oil is likely to reduce both economic and ecological impacts of the process in the fat and oil industry.

  18. Pleural ultrasound for clinicians.

    PubMed

    Porcel, J M

    2016-11-01

    Pleural ultrasonography is useful for identifying and characterising pleural effusions, solid pleural lesions (nodules, masses, swellings) and pneumothorax. Pleural ultrasonography is also considered the standard care for guiding interventionist procedures on the pleura at the patient's bedside (thoracentesis, drainage tubes, pleural biopsies and pleuroscopy). Hospitals should promote the acquisition of portable ultrasound equipment to increase the patient's safety.

  19. Ultrasound and the IRB

    ERIC Educational Resources Information Center

    Epstein, Melissa A.

    2005-01-01

    The purpose of this paper is to assist researchers in writing their research protocols and subject consent forms so that both the Institutional Review Board (IRB) and subjects are assured of the minimal risk associated with diagnostic B-scan ultrasound as it is used in speech research. There have been numerous epidemiological studies on fetal…

  20. History of intraoperative ultrasound.

    PubMed

    Makuuchi, M; Torzilli, G; Machi, J

    1998-11-01

    Intraoperative ultrasound (IOUS) using A-mode or non-real-time B-mode imaging started in the 1960s; however, it was not widely accepted mainly because of difficulty in image interpretation. In the late 1970s, IOUS became one of the topics in the surgical communities upon the introduction of high-frequency real-time B-mode ultrasound. Special probes for operative use were developed. In the 1980s, all over the world the use of IOUS spread to a variety of surgical fields, such as hepatobiliary pancreatic surgery, neurosurgery, and cardiovascular surgery. IOUS changed hepatic surgery dramatically because IOUS was the only modality that was capable of delineating and examining the interior of the liver during surgery. After 1990, color Doppler imaging and laparoscopic ultrasound were incorporated into IOUS. Currently, IOUS is considered an indispensable operative procedure for intraoperative decision-making and guidance of surgical procedures. For better surgical practice, education of surgeons in the use of ultrasound is the most important issue.

  1. Intravascular ultrasound elastography.

    PubMed

    van der Steen, A F; de Korte, C L; Céspedes, E I

    1998-10-01

    Intravascular Ultrasound Blastography. The response of a tissue to mechanical excitation is a function of its mechanical properties. Excitation can be dynamic or quasistatic in nature. The response (e.g. displacement, velocity, compression) can be measured via ultrasound. This is the main principle underlying ultrasound elasticity imaging, sonoelasticity imaging, or ultrasound elastography. It is of great interest to know the local hardness of vessel wall and plaques. Intravascular elastography yields information unavailable or inconclusive if obtained from IVUS alone and thus contributes to more correct diagnosis. Potentially it can be used for therapy guidance. During the last decade several working groups used elastography in intravascular applications with varying success. In this paper we discuss the various approaches by different working groups. Focus will be on the approach of the Rotterdam group. Using a 30 MHz IVUS catheter, RF data are acquired from vessels in vitro at different intraluminal pressures. Local tissue displacement estimation by cross-correlation is followed by computation of the local strain. The resulting image supplies local information on the elastic properties of the vessel and plaque with high spatial resolution. Feasibility and usefulness are shown by means of phantom measurements. Furthermore, initial in vitro results of femoral arteries and correlation with histology are discussed. Phantom data show that the elastograms reveal information not presented by the echogram. In vitro artery data prove that in principle elastography is capable of identifying plaque composition where echography fails.

  2. A resonance-free nano-film airborne ultrasound emitter

    NASA Astrophysics Data System (ADS)

    Daschewski, Maxim; Harrer, Andrea; Prager, Jens; Kreutzbruck, Marc; Beck, Uwe; Lange, Thorid; Weise, Matthias

    2013-01-01

    In this contribution we present a novel thermo-acoustic approach for the generation of broad band airborne ultrasound and investigate the applicability of resonance-free thermo-acoustic emitters for very short high pressure airborne ultrasound pulses. We report on measurements of thermo-acoustic emitter consisting of a 30 nm thin metallic film on a usual soda-lime glass substrate, generating sound pressure values of more than 140 dB at 60 mm distance from the transducer and compare the results with conventional piezoelectric airborne ultrasound transducers. Our experimental investigations show that such thermo-acoustic devices can be used as broad band emitters using pulse excitation.

  3. Laser ultrasound technology for fault detection on carbon fiber composites

    NASA Astrophysics Data System (ADS)

    Seyrkammer, Robert; Reitinger, Bernhard; Grün, Hubert; Sekelja, Jakov; Burgholzer, Peter

    2014-05-01

    The marching in of carbon fiber reinforced polymers (CFRPs) to mass production in the aeronautic and automotive industry requires reliable quality assurance methods. Laser ultrasound (LUS) is a promising nondestructive testing technique for sample inspection. The benefits compared to conventional ultrasound (US) testing are couplant free measurements and an easy access to complex shapes due to remote optical excitation and detection. Here the potential of LUS is present on composite test panels with relevant testing scenarios for industry. The results are evaluated in comparison to conventional ultrasound used in the aeronautic industry.

  4. [Does ultrasound have an adverse effect on the fertility of women?].

    PubMed

    Quéreux, C; Mazili, M L; Desroches, A; Garnier, R; Slaoui, K; Bajolle, F; Wahl, P

    1986-01-01

    Fifty women who were subfertile received artificial insemination from donors (A.I.D.) with ultrasound monitoring of ovulation. They were compared with an identical number of women who were inseminated without ultrasound control. The series side by side showed that there was a lower fertilisation rate in those who were monitored (4.2% compared with 6.2%) per month on an average over six months as compared with those who were not monitored by ultrasound, and those who were monitored took significantly longer to become pregnant than those who were not monitored. Because of these results the authors wonder whether ultrasounds are harmful for ovulation.

  5. In vitro investigation of ultrasound-induced oxidative stress on human lens epithelial cells.

    PubMed

    Rwei, Patrick; Alex Gong, Cihun-Siyong; Luo, Li-Jyuan; Lin, Meng-Bo; Lai, Jui-Yang; Liu, Hao-Li

    2017-01-22

    The effect of ultrasound exposure on human lens epithelial cells (HLE-B3) was investigated in vitro, specifically on the generation of oxidative stress upon ultrasound application using various clinically-relevant settings. In addition to ultrasound-induced heat effects, oxidative stress has been recently proposed as one of the main mechanisms for ultrasound-induced effects on human cells. In this work, the levels of biocompatibility and generation of oxidative stress by exposure of ultrasound to HLE-B3 were evaluated quantitatively and qualitatively by the MTT assay, Live/Dead assay, reactive oxygen species (ROS) and intracellular calcium level. Oxidative stress induction is traditionally achieved through administrations of H2O2 and thus the administration of H2O2 was used as the positive control group for comparison herein. Concerning the administrations of H2O2 are considered invasive and may potentially have side effects, ultrasound as physical stimulation could be a safer and non-invasive method to induce similar oxidative stress environments. The effect of ultrasound on cell viability and induction of oxidative stress increases with ultrasound intensity. The result reveals that the continuous ultrasound has a positive impact on the oxidative stress levels but does negatively on the cell viability, as compared to the pulsed ultrasound. Furthermore, our work demonstrates that the exposure of 58 kPa continuous ultrasound without microbubbles can maintain acceptable cell viability and produce oxidative stress effects similar to the traditional administrations of H2O2. In summary, exposure of ultrasound can generate oxidative stress comparable to traditional administrations of H2O2. The effect of generating oxidative stress is adjustable through ultrasound parameters, including the pulsed or continuous wave, the intensity of ultrasound and addition of microbubbles.

  6. Tumor functional and molecular imaging utilizing ultrasound and ultrasound-mediated optical techniques.

    PubMed

    Yuan, Baohong; Rychak, Joshua

    2013-02-01

    Tumor functional and molecular imaging has significantly contributed to cancer preclinical research and clinical applications. Among typical imaging modalities, ultrasonic and optical techniques are two commonly used methods; both share several common features such as cost efficiency, absence of ionizing radiation, relatively inexpensive contrast agents, and comparable maximum-imaging depth. Ultrasonic and optical techniques are also complementary in imaging resolution, molecular sensitivity, and imaging space (vascular and extravascular). The marriage between ultrasonic and optical techniques takes advantages of both techniques. This review introduces tumor functional and molecular imaging using microbubble-based ultrasound and ultrasound-mediated optical imaging techniques.

  7. Characterization and Ultrasound-Pulse Mediated Destruction of Ultrasound Contrast Microbubbles

    NASA Astrophysics Data System (ADS)

    Sarkar, Kausik; Jain, Pankaj; Chatterjee, Dhiman

    2006-05-01

    Intravenously injected encapsulated microbubbles improve the contrast of an ultrasound image. Their destruction is used in measuring blood flow, stimulating arteriogenesis, and drug delivery. We measure attenuation and scattering of ultrasound through solution of commercial contrast agents such as Sonazoid and Definity. We have developed a number of different interfacial rheology models for the encapsulation of such microbubbles. By matching with experimentally measured attenuation, we obtain the characteristic rheological parameters. We compare model predictions with measured subharmonic responses. We also investigate microbubble destruction under acoustic excitation by measuring time-varying attenuation data.

  8. Ultrasound-mediated nail drug delivery system.

    PubMed

    Abadi, Danielle; Zderic, Vesna

    2011-12-01

    A novel ultrasound-mediated drug delivery system has been developed for treatment of a nail fungal disorder (onychomycosis) by improving delivery to the nail bed using ultrasound to increase the permeability of the nail. The slip-in device consists of ultrasound transducers and drug delivery compartments above each toenail. The device is connected to a computer, where a software interface allows users to select their preferred course of treatment. In in vitro testing, canine nails were exposed to 3 energy levels (acoustic power of 1.2 W and exposure durations of 30, 60, and 120 seconds). A stereo -microscope was used to determine how much of a drug-mimicking compound was delivered through the nail layers by measuring brightness on the cross section of each nail tested at each condition, where brightness level decreases coincide with increases in permeability. Each of the 3 energy levels tested showed statistical significance when compared to the control (P < .05) with a permeability factor of 1.3 after 30 seconds of exposure, 1.3 after 60 seconds, and 1.5 after 120 seconds, where a permeability factor of 1 shows no increase in permeability. Current treatments for onychomycosis include systemic, topical, and surgical. Even when used all together, these treatments typically take a long time to result in nail healing, thus making this ultrasound-mediated device a promising alternative.

  9. Synthesis of laboratory Ultrasound Contrast Agents.

    PubMed

    Park, Jingam; Park, Donghee; Shin, Unchul; Moon, Sanghyub; Kim, Chihyun; Kim, Han Sung; Park, Hyunjin; Choi, Kiju; Jung, Bongkwang; Oh, Jaemin; Seo, Jongbum

    2013-10-21

    Ultrasound Contrast Agents (UCAs) were developed to maximize reflection contrast so that organs can be seen clearly in ultrasound imaging. UCAs increase the signal to noise ratio (SNR) by linear and non-linear mechanisms and thus help more accurately visualize the internal organs and blood vessels. However, the UCAs on the market are not only expensive, but are also not optimized for use in various therapeutic research applications such as ultrasound-aided drug delivery. The UCAs fabricated in this study utilize conventional lipid and albumin for shell formation and perfluorobutane as the internal gas. The shape and density of the UCA bubbles were verified by optical microscopy and Cryo SEM, and compared to those of the commercially available UCAs, Definity® and Sonovue®. The size distribution and characteristics of the reflected signal were also analyzed using a particle size analyzer and ultrasound imaging equipment. Our experiments indicate that UCAs composed of spherical microbubbles, the majority of which were smaller than 1 um, were successfully synthesized. Microbubbles 10 um or larger were also identified when different shell characteristics and filters were used. These laboratory UCAs can be used for research in both diagnoses and therapies.

  10. 3D imaging options and ultrasound contrast agents for the ultrasound assessment of pediatric rheumatic patients.

    PubMed

    Madej, Tomasz

    2013-12-01

    The application of 3D imaging in pediatric rheumatology helps to make the assessment of inflammatory changes more objective and to estimate accurately their volume and the actual response to treatment in the course of follow-up examinations. Additional interesting opportunities are opened up by the vascularity analysis with the help of power Doppler and color Doppler in 3D imaging. Contrast-enhanced ultrasound examinations enable a more sensitive assessment of the vascularity of inflamed structures of the locomotor system, and a more accurate analysis of treatment's effect on changes in vascularity, and thereby the inflammation process activity, as compared to the classical options of power and color Doppler. The equipment required, time limitations, as well as the high price in the case of contrast-enhanced ultrasound, contribute to the fact that the 3D analysis of inflammatory changes and contrast-enhanced ultrasound examinations are not routinely applied for pediatric patients.

  11. Two-dimensional ultrasound measurement of thyroid gland volume: a new equation with higher correlation with 3-D ultrasound measurement.

    PubMed

    Ying, Michael; Yung, Dennis M C; Ho, Karen K L

    2008-01-01

    This study aimed to develop a new two-dimensional (2-D) ultrasound thyroid volume estimation equation using three-dimensional (3-D) ultrasound as the standard of reference, and to compare the thyroid volume estimation accuracy of the new equation with three previously reported equations. 2-D and 3-D ultrasound examinations of the thyroid gland were performed in 150 subjects with normal serum thyrotropin (TSH, thyroid-stimulating hormone) and free thyroxine (fT4) levels (63 men and 87 women, age range: 17 to 71 y). In each subject, the volume of both thyroid lobes was measured by 3-D ultrasound. On 2-D ultrasound, the craniocaudal (CC), lateromedial (LM) and anteroposterior (AP) dimensions of the thyroid lobes were measured. The equation was derived by correlating the volume of the thyroid lobes measured with 3-D ultrasound and the product of the three dimensions measured with 2-D ultrasound using linear regression analysis, in 75 subjects without thyroid nodule. The accuracy of thyroid volume estimation of the new equation and the three previously reported equations was evaluated and compared in another 75 subjects (without thyroid nodule, n = 30; with thyroid nodule, n = 45). It is suggested that volume of thyroid lobe may be estimated as: volume of thyroid lobe = 0.38.(CC.LM.AP) + 1.76. Result showed that the new equation (16.9% to 36.1%) had a significantly smaller thyroid volume estimation error than the previously reported equations (20.8% to 54.9%) (p < 0.05). There was a significantly larger thyroid volume estimation error when thyroid glands with nodules were examined (p < 0.05). With the use of the appropriate thyroid volume equation, 2-D ultrasound can be a useful alternative in thyroid volume measurement when 3-D ultrasound is not available.

  12. Ultrasound-Assisted Freezing

    NASA Astrophysics Data System (ADS)

    Delgado, A. E.; Sun, Da-Wen

    Freezing is a well-known preservation method widely used in the food industry. The advantages of freezing are to a certain degree counterbalanced by the risk of damage caused by the formation and size of ice crystals. Over recent years new approaches have been developed to improve and control the crystallization process, and among these approaches sonocrystallization has proved to be very useful, since it can enhance both the nucleation rate and the crystal growth rate. Although ultrasound has been successfully used for many years in the evaluation of various aspects of foods and in medical applications, the use of power ultrasound to directly improve processes and products is less popular in food manufacturing. Foodstuffs are very complex materials, and research is needed in order to define the specific sound parameters that aid the freezing process and that can later be used for the scale-up and production of commercial frozen food products.

  13. [High frequency ultrasound].

    PubMed

    Sattler, E

    2015-07-01

    Diagnostic ultrasound has become a standard procedure in clinical dermatology. Devices with intermediate high frequencies of 7.5-15 MHz are used in dermato-oncology for the staging and postoperative care of skin tumor patients and in angiology for improved vessel diagnostics. In contrast, the high frequency ultrasound systems with 20-100 MHz probes offer a much higher resolution, yet with a lower penetration depth of about 1 cm. The main indications are the preoperative measurements of tumor thickness in malignant melanoma and other skin tumors and the assessment of inflammatory and soft tissue diseases, offering information on the course of these dermatoses and allowing therapy monitoring. This article gives an overview on technical principles, devices, mode of examination, influencing factors, interpretation of the images, indications but also limitations of this technique.

  14. Sparsity driven ultrasound imaginga)

    PubMed Central

    Tuysuzoglu, Ahmet; Kracht, Jonathan M.; Cleveland, Robin O.; C¸etin, Müjdat; Karl, W. Clem

    2012-01-01

    An image formation framework for ultrasound imaging from synthetic transducer arrays based on sparsity-driven regularization functionals using single-frequency Fourier domain data is proposed. The framework involves the use of a physics-based forward model of the ultrasound observation process, the formulation of image formation as the solution of an associated optimization problem, and the solution of that problem through efficient numerical algorithms. The sparsity-driven, model-based approach estimates a complex-valued reflectivity field and preserves physical features in the scene while suppressing spurious artifacts. It also provides robust reconstructions in the case of sparse and reduced observation apertures. The effectiveness of the proposed imaging strategy is demonstrated using experimental data. PMID:22352501

  15. Ultrasound promoted catalytic liquid-phase dehydrogenation of isopropanol for Isopropanol-Acetone-Hydrogen chemical heat pump.

    PubMed

    Xu, Min; Xin, Fang; Li, Xunfeng; Huai, Xiulan; Liu, Hui

    2015-03-01

    The apparent kinetic of the ultrasound assisted liquid-phase dehydrogenation of isopropanol over Raney nickel catalyst was determined in the temperature range of 346-353 K. Comparison of the effects of ultrasound and mechanical agitation on the isopropanol dehydrogenation was investigated. The ultrasound assisted dehydrogenation rate was significantly improved when relatively high power density was used. Moreover, the Isopropanol-Acetone-Hydrogen chemical heat pump (IAH-CHP) with ultrasound irradiation, in which the endothermic reaction is exposure to ultrasound, was proposed. A mathematical model was established to evaluate its energy performance in term of the coefficient of performance (COP) and the exergy efficiency, into which the apparent kinetic obtained in this work was incorporated. The operating performances between IAH-CHP with ultrasound and mechanical agitation were compared. The results indicated that the superiority of the IAH-CHP system with ultrasound was present even if more than 50% of the power of the ultrasound equipment was lost.

  16. Manipulating neuronal activity with low frequency transcranial ultrasound

    NASA Astrophysics Data System (ADS)

    Moore, Michele Elizabeth

    Stimulation of the rodent cerebral cortex is used to investigate the underlying biological basis for the restorative effects of slow wave sleep. Neuronal activation by optogenetic and ultrasound stimulation elicits changes in action potentials across the cerebral cortex that are recorded as electroencephalograms. Optogenetic stimulation requires an invasive implantation procedure limiting its application in human studies. We sought to determine whether ultrasound stimulation could be as effective as optogenetic techniques currently used, in an effort to further understand the physiological and metabolic requirements of sleep. We successfully recorded electroencephalograms in response to transcranial ultrasound stimulation of the barrel cortex at 1 and 7 Hz frequencies, comparing them to those recorded in response to optogenetic stimuli applied at the same frequencies. Our results showed application of a 473 nm blue LED positioned 6 cm above the skull and ultrasound stimulation at an output voltage of 1000 mVpp produced electroencephalograms with physiological responses of similar amplitude. We concluded that there exists an intensity-proportionate response in the optogenetic stimulation, but not with ultrasound stimulation at the frequencies we surveyed. Activation of neuronal cells in response to optogenetic stimulation in a Thy1-ChR2 transgenic mouse line is specifically targeted to pyramidal cells in the cerebral cortex. ChR2 responses to optogenetic stimulation are mediated by a focal activation of neuronal ion channels. We measured electrophysiological responses to ultrasound stimulation, comparing them to those recorded from optogenetic stimuli. Our results show striking similarities between ultrasound-induced responses and optogenetically-induced responses, which may indicate that transcranial ultrasound stimulation is also mediated by ion channel dependent processes in cerebral cortical neurons. The biophysical substrates for electrical excitability of

  17. Clinical ophthalmic ultrasound improvements

    NASA Technical Reports Server (NTRS)

    Garrison, J. B.; Piro, P. A.

    1981-01-01

    The use of digital synthetic aperture techniques to obtain high resolution ultrasound images of eye and orbit was proposed. The parameters of the switched array configuration to reduce data collection time to a few milliseconds to avoid eye motion problems in the eye itself were established. An assessment of the effects of eye motion on the performance of the system was obtained. The principles of synthetic techniques are discussed. Likely applications are considered.

  18. Tissue identification by ultrasound

    NASA Technical Reports Server (NTRS)

    Lecroissette, D. H.; Heyser, R. C.; Gammell, P. M.; Wilson, R. L.

    1978-01-01

    The ultrasonic properties of animal and human soft tissue were measured over the frequency range of 1.5 to 10.0 MHz. The method employed a swept-frequency, coherent technique known as time delay spectrometry. Measurements of attenuation versus frequency on liver, backfat, kidney, pancreas, spleen, breast, and other tissue were made. Considerable attention was paid to tissue handling and in determining the effects of fixing on the attenuation of ultrasound in the tissue.

  19. Ultrasound Imaging Initiative

    DTIC Science & Technology

    2003-01-01

    texture mapping hardware," IEEE Tranactions on Information Technology in Biomedicine, Submitted. [14] C.R. Castro Pareja , J.M. Jagadeesh and R. Shekhar...modulation in real-time three-dimensional sparse synthetic aperture ultrasound imaging systems "* Carlos R. Castro Pareja , Masters of Science, The Ohio...C.R. Castro Pareja , "An architecture for real-time image registration," M.S. Thesis, The Ohio State University, March 2002. 14. C.R. Castro Pareja , R

  20. Musculoskeletal ultrasound in pediatric rheumatology

    PubMed Central

    2011-01-01

    Although musculoskeletal ultrasound (MSUS) has emerged as an indispensible tool among physicians involved in musculoskeletal medicine in the last two decades, only recently has it become more attractive to pediatric rheumatologists. Thereafter, the use of MSUS in pediatric rheumatology has started to increase. Yet, an ever-growing body of literature shows parity and even superiority of MSUS when compared to physical examination and other imaging modalities. MSUS is suitable for examination of children of all ages and it has certain advantages over other imaging modalities; as it is cheaper, mobile, instantly accessible bedside, easy to combine with clinical assessment (interactivity) and non-invasive. It does not require sedation, which facilitates repetitive examinations. Assessment of multiple locations is possible during the same session. Agitation is rarely a problem and small children can be seated in their parents' lap or they can even play while being examined. PMID:21910870

  1. Can anatomists teach living anatomy using ultrasound as a teaching tool?

    PubMed

    Jurjus, Rosalyn A; Dimorier, Kathryn; Brown, Kirsten; Slaby, Frank; Shokoohi, Hamid; Boniface, Keith; Liu, Yiju Teresa

    2014-01-01

    The utilization of bedside ultrasound by an increasing number of medical specialties has created the need for more ultrasound exposure and teaching in medical school. Although there is a widespread support for more vertical integration of ultrasound teaching throughout the undergraduate curriculum, little is known about whether the quality of ultrasound teaching differs if performed by anatomists or clinicians. The purpose of this study is to compare medical students' evaluation of ultrasound anatomy teaching by clinicians and anatomists. Hands-on interactive ultrasound sessions were scheduled as part of the gross anatomy course following principles of adult learning and instructional design. Seven teachers (three anatomists and four clinicians) taught in each session. Before each session, anatomists were trained in ultrasound by clinicians. Students were divided into groups, rotated teachers between sessions, and completed evaluations. Results indicated students perceived the two groups as comparable for all factors except for knowledge organization and the helpfulness of ultrasound for understanding anatomy (P < 0.001). However, results from unpaired samples t-tests demonstrated a nonstatistically significant difference between the groups within each session for both questions. Moreover, students' test performance for both groups was similar. This study demonstrated that anatomists can teach living anatomy using ultrasound with minimal training as well as clinicians, and encourage the teaching of living anatomy by anatomists in human anatomy courses using ultrasound. Repeating this study at a multicenter level is currently being considered to further validate our conclusion.

  2. Physics and instrumentation of ultrasound.

    PubMed

    Lawrence, John P

    2007-08-01

    A thorough understanding of the physics of ultrasound waves and the instrumentation will provide the user with a better understanding of the capabilities and limitations of ultrasound equipment. The ultrasound machine combines two technologies: image production (M-mode and 2-dimensional imaging) with Doppler assessment (continuous and pulse wave as well as color-flow mapping). These distinct technologies have been combined to provide the examiner with the ability to make accurate and comprehensive diagnoses and guide therapeutic intervention.

  3. Doppler Ultrasound: What Is It Used for?

    MedlinePlus

    ... in your neck (carotid artery stenosis) A Doppler ultrasound can estimate how fast blood flows by measuring the rate of change in its pitch (frequency). During a Doppler ultrasound, a technician trained in ultrasound imaging (sonographer) presses ...

  4. Focused Ultrasound Surgery for Uterine Fibroids

    MedlinePlus

    Focused ultrasound surgery for uterine fibroids Overview By Mayo Clinic Staff Focused ultrasound surgery (FUS) is a noninvasive treatment option for ... whether you're a good candidate for focused ultrasound surgery, your doctor may perform a pelvic magnetic ...

  5. Clinician-performed thyroid ultrasound.

    PubMed

    Coltrera, Marc D

    2014-08-01

    This article is intended to demystify the process for those with a potential interest in acquiring ultrasound skills. It is not intended to be a comprehensive review of head and neck ultrasound but, rather, is focused on the bare minimum requirements and considerations involved in clinician-performed ultrasound. The article covers the initial diagnosis and the unparalleled usefulness of ultrasound for surgical planning just before incision. Further readings are listed at the end of the article to direct the reader to some excellent texts to help build confidence and experience.

  6. Smart Ultrasound Remote Guidance Experiment (SURGE)- Concept of Operations Evaluation for Using Remote Guidance Ultrasound for Planetary Space Flight

    NASA Technical Reports Server (NTRS)

    Hurst, Victor, IV; Peterson, Sean; Garcia, Kathleen; Sargsyan, Ashot; Ebert, Douglas; Ham, David; Amponsah, David; Dulchavsky, Scott

    2010-01-01

    Introduction Use of remote guidance (RG) techniques aboard the International Space Station (ISS) has enabled astronauts to collect diagnostic-level ultrasound images. Exploration class missions will require this cohort of (typically) non-formally trained sonographers to operate with greater autonomy given the longer communication delays (2 seconds for ISS vs. >6 seconds for missions beyond the Moon) and communication blackouts. To determine the feasibility and training requirements for autonomous ultrasound image collection by non-expert ultrasound operators, ultrasound images were collected from a similar cohort using three different image collection protocols: RG only, RG with a computer-based learning tool (LT), and autonomous image collection with LT. The groups were assessed for both image quality and time to collect the images. Methods Subjects were randomized into three groups: RG only, RG with LT, and autonomous with LT. Each subject received 10 minutes of standardized training before the experiment. The subjects were tasked with making the following ultrasound assessments: 1) bone fracture and 2) focused assessment with sonography in trauma (FAST) to assess a patient s abdomen. Human factors-related questionnaire data were collected immediately after the assessments. Results The autonomous group did not out-perform the two groups that received RG. The mean time for the autonomous group to collect images was less than the RG groups, however the mean image quality for the autonomous group was less compared to both RG groups. Discussion Remote guidance continues to produce higher quality ultrasound images than autonomous ultrasound operation. This is likely due to near-instant feedback on image quality from the remote guider. Expansion in communication time delays, however, diminishes the capability to provide this feedback, thus requiring more autonomous ultrasound operation. The LT has the potential to be an excellent training and coaching component for

  7. ALTERNATIVE ROUTES FOR CATALYST PREPARATION: USE OF ULTRASOUND AND MICROWAVE IRRADIATION FOR THE PREPARATION OF VANADIUM PHOSPHORUS OXIDE CATALYST AND THEIR ACTIVITY FOR HYDROCARBON OXIDATION

    EPA Science Inventory

    Vanadium phosphorus oxide (VPO) has been prepared using ultrasound and microwave irradiation methods and compared with the catalyst prepared by conventional method for both the phase composition and activity for hydrocarbon oxidation. It is found that ultrasound irradiation metho...

  8. Numerical simulation of piezoelectric effect of bone under ultrasound irradiation

    NASA Astrophysics Data System (ADS)

    Hosokawa, Atsushi

    2015-07-01

    The piezoelectric effect of bone under ultrasound irradiation was numerically simulated using an elastic finite-difference time-domain method with piezoelectric constitutive equations (PE-FDTD method). First, to demonstrate the validity of the PE-FDTD method, the ultrasound propagation in piezoelectric ceramics was simulated and then compared with the experimental results. The simulated and experimental waveforms propagating through the ceramics were in good agreement. Next, the piezoelectric effect of human cortical bone on the ultrasound propagation was investigated by PE-FDTD simulation. The simulated result showed that the difference between the waveforms propagating through the bone without and with piezoelectricity was negligible. Finally, the spatial distributions of the electric fields in a human femur induced by ultrasound irradiation were simulated. The electric fields were changed by a bone fracture, which depended on piezoelectric anisotropy. In conclusion, the PE-FDTD method is considered to be useful for investigating the piezoelectric effect of bone.

  9. Intracranial Applications of MR Imaging-Guided Focused Ultrasound.

    PubMed

    Khanna, N; Gandhi, D; Steven, A; Frenkel, V; Melhem, E R

    2017-03-01

    Initially used in the treatment of prostate cancer and uterine fibroids, the role of focused ultrasound has expanded as transcranial acoustic wave distortion and other limitations have been overcome. Its utility relies on focal energy deposition via acoustic wave propagation. The duty cycle and intensity of focused ultrasound influence the rate of energy deposition and result in unique physiologic and biomechanical effects. Thermal ablation via high-intensity continuous exposure generates coagulative necrosis of tissues. High-intensity, pulsed application reduces temporally averaged energy deposition, resulting in mechanical effects, including reversible, localized BBB disruption, which enhances neurotherapeutic agent delivery. While the precise mechanisms remain unclear, low-intensity, pulsed exposures can influence neuronal activity with preservation of cytoarchitecture. Its noninvasive nature, high-resolution, radiation-free features allow focused ultrasound to compare favorably with other modalities. We discuss the physical characteristics of focused ultrasound devices, the biophysical mechanisms at the tissue level, and current and emerging applications.

  10. Combined ultrasound and MR imaging to guide focused ultrasound therapies in the brain.

    PubMed

    Arvanitis, Costas D; Livingstone, Margaret S; McDannold, Nathan

    2013-07-21

    Several emerging therapies with potential for use in the brain, harness effects produced by acoustic cavitation--the interaction between ultrasound and microbubbles either generated during sonication or introduced into the vasculature. Systems developed for transcranial MRI-guided focused ultrasound (MRgFUS) thermal ablation can enable their clinical translation, but methods for real-time monitoring and control are currently lacking. Acoustic emissions produced during sonication can provide information about the location, strength and type of the microbubble oscillations within the ultrasound field, and they can be mapped in real-time using passive imaging approaches. Here, we tested whether such mapping can be achieved transcranially within a clinical brain MRgFUS system. We integrated an ultrasound imaging array into the hemisphere transducer of the MRgFUS device. Passive cavitation maps were obtained during sonications combined with a circulating microbubble agent at 20 targets in the cingulate cortex in three macaques. The maps were compared with MRI-evident tissue effects. The system successfully mapped microbubble activity during both stable and inertial cavitation, which was correlated with MRI-evident transient blood-brain barrier disruption and vascular damage, respectively. The location of this activity was coincident with the resulting tissue changes within the expected resolution limits of the system. While preliminary, these data clearly demonstrate, for the first time, that it is possible to construct maps of stable and inertial cavitation transcranially, in a large animal model, and under clinically relevant conditions. Further, these results suggest that this hybrid ultrasound/MRI approach can provide comprehensive guidance for targeted drug delivery via blood-brain barrier disruption and other emerging ultrasound treatments, facilitating their clinical translation. We anticipate that it will also prove to be an important research tool that will

  11. Combined ultrasound and MR imaging to guide focused ultrasound therapies in the brain

    NASA Astrophysics Data System (ADS)

    Arvanitis, Costas D.; Livingstone, Margaret S.; McDannold, Nathan

    2013-07-01

    Several emerging therapies with potential for use in the brain, harness effects produced by acoustic cavitation—the interaction between ultrasound and microbubbles either generated during sonication or introduced into the vasculature. Systems developed for transcranial MRI-guided focused ultrasound (MRgFUS) thermal ablation can enable their clinical translation, but methods for real-time monitoring and control are currently lacking. Acoustic emissions produced during sonication can provide information about the location, strength and type of the microbubble oscillations within the ultrasound field, and they can be mapped in real-time using passive imaging approaches. Here, we tested whether such mapping can be achieved transcranially within a clinical brain MRgFUS system. We integrated an ultrasound imaging array into the hemisphere transducer of the MRgFUS device. Passive cavitation maps were obtained during sonications combined with a circulating microbubble agent at 20 targets in the cingulate cortex in three macaques. The maps were compared with MRI-evident tissue effects. The system successfully mapped microbubble activity during both stable and inertial cavitation, which was correlated with MRI-evident transient blood-brain barrier disruption and vascular damage, respectively. The location of this activity was coincident with the resulting tissue changes within the expected resolution limits of the system. While preliminary, these data clearly demonstrate, for the first time, that it is possible to construct maps of stable and inertial cavitation transcranially, in a large animal model, and under clinically relevant conditions. Further, these results suggest that this hybrid ultrasound/MRI approach can provide comprehensive guidance for targeted drug delivery via blood-brain barrier disruption and other emerging ultrasound treatments, facilitating their clinical translation. We anticipate that it will also prove to be an important research tool that will

  12. Ultrasound-Guided Lateral Femoral Cutaneous Nerve Conduction Study

    PubMed Central

    Park, Bum Jun; Joeng, Eui Soo; Choi, Jun Kyu; Kang, Seok; Yoon, Joon Shik

    2015-01-01

    Objective To verify the utility of the lateral femoral cutaneous nerve (LFCN) ultrasound-guided conduction technique compared to that of the conventional nerve conduction technique. Methods Fifty-eight legs of 29 healthy participants (18 males and 11 females; mean age, 42.7±14.9 years) were recruited. The conventional technique was performed bilaterally. The LFCN was localized by ultrasound. Cross-sectional area (CSA) of the LFCN and the distance between the anterior superior iliac spine (ASIS) and the LFCN was measured. The nerve conduction study was repeated with the corrected cathode location. Sensory nerve action potential (SNAP) amplitudes of the LFCN were recorded and compared between the ultrasound-guided and conventional techniques. Results Mean body mass index of the participants was 23.7±3.5 kg/m2, CSA was 4.2±1.9 mm2, and the distance between the ASIS and LFCN was 5.6±1.7 mm. The mean amplitude values were 6.07±0.52 µV and 6.66±0.54 µV using the conventional and ultrasound-guided techniques, respectively. The SNAP amplitude of the LFCN using the ultrasound-guided technique was significantly larger than that recorded using the conventional technique. Conclusion Correcting the stimulation position using the ultrasound-guided technique helped obtain increased SNAP amplitude. PMID:25750871

  13. Ultrasound for low temperature dyeing of wool with acid dye.

    PubMed

    Ferrero, F; Periolatto, M

    2012-05-01

    The possibility of reducing the temperature of conventional wool dyeing with an acid levelling dye using ultrasound was studied in order to reach exhaustion values comparable to those obtained with the standard procedure at 98 °C, obtaining dyed samples of good quality. The aim was to develop a laboratory method that could be transferred at industrial level, reducing both the energy consumption and fiber damage caused by the prolonged exposure to high temperature without the use of polluting auxiliary agents. Dyeings of wool fabrics were carried out in the temperature range between 60 °C and 80 °C using either mechanical or ultrasound agitation of the bath and coupling the two methods to compare the results. For each dyeing, the exhaustion curves of the dye bath were determined and the better results of dyeing kinetics were obtained with ultrasound coupled with mechanical stirring. Hence the corresponding half dyeing times, absorption rate constants according to Cegarra-Puente modified equation and ultrasonic efficiency were calculated in comparison with mechanical stirring alone. In the presence of ultrasound the absorption rate constants increased by at least 50%, at each temperature, confirming the synergic effect of sonication on the dyeing kinetics. Moreover the apparent activation energies were also evaluated and the positive effect of ultrasound was ascribed to the pre-exponential factor of the Arrhenius equation. It was also shown that the effect of ultrasound at 60 °C was just on the dye bath, practically unaffecting the wool fiber surface, as confirmed by the results of SEM analysis. Finally, fastness tests to rubbing and domestic laundering yielded good values for samples dyed in ultrasound assisted process even at the lower temperature. These results suggest the possibility, thanks to the use of ultrasound, to obtain a well equalized dyeing on wool working yet at 60°C, a temperature process strongly lower than 98°C, currently used in industry

  14. Ultrasound speckle tracking for radial, longitudinal and circumferential strain estimation of the carotid artery--an in vitro validation via sonomicrometry using clinical and high-frequency ultrasound.

    PubMed

    Larsson, Matilda; Heyde, Brecht; Kremer, Florence; Brodin, Lars-Åke; D'hooge, Jan

    2015-02-01

    Ultrasound speckle tracking for carotid strain assessment has in the past decade gained interest in studies of arterial stiffness and cardiovascular diseases. The aim of this study was to validate and directly contrast carotid strain assessment by speckle tracking applied on clinical and high-frequency ultrasound images in vitro. Four polyvinyl alcohol phantoms mimicking the carotid artery were constructed with different mechanical properties and connected to a pump generating carotid flow profiles. Gray-scale ultrasound long- and short-axis images of the phantoms were obtained using a standard clinical ultrasound system, Vivid 7 (GE Healthcare, Horten, Norway) and a high-frequency ultrasound system, Vevo 2100 (FUJIFILM, VisualSonics, Toronto, Canada) with linear-array transducers (12L/MS250). Radial, longitudinal and circumferential strains were estimated using an in-house speckle tracking algorithm and compared with reference strain acquired by sonomicrometry. Overall, the estimated strain corresponded well with the reference strain. The correlation between estimated peak strain in clinical ultrasound images and reference strain was 0.91 (p<0.001) for radial strain, 0.73 (p<0.001) for longitudinal strain and 0.90 (p<0.001) for circumferential strain and for high-frequency ultrasound images 0.95 (p<0.001) for radial strain, 0.93 (p<0.001) for longitudinal strain and 0.90 (p<0.001) for circumferential strain. A significant larger bias and root mean square error was found for circumferential strain estimation on clinical ultrasound images compared to high frequency ultrasound images, but no significant difference in bias and root mean square error was found for radial and longitudinal strain when comparing estimation on clinical and high-frequency ultrasound images. The agreement between sonomicrometry and speckle tracking demonstrates that carotid strain assessment by ultrasound speckle tracking is feasible.

  15. Ultrasound Thermal Field Imaging of Opaque Fluids

    NASA Technical Reports Server (NTRS)

    Andereck, C. David

    1999-01-01

    studying convective fluid flow in crystal growth, because particle seeding is unacceptable and flow velocities are typically too low to be resolved, and may be even lower in microgravity conditions where buoyancy forces are negligible. We will investigate a different use of ultrasound to probe the flows of opaque fluids non-intrusively and without the use of seed particles: our goal is to ultrasonically visualize the thermal field of opaque fluids with relatively high spatial resolution. The proposed technique relies upon the variation of sound speed with temperature of the fluid. A high frequency ultra-sound pulse passing through a fluid-filled chamber will traverse the chamber in a time determined by the relevant chamber dimension and the temperature of the fluid through which the pulse passes. With high time-resolution instrumentation that compares the excitation signal with the received pulse we can detect the influence of the fluid temperature on the pulse travel time. This is effectively an interferometric system, which in its optical form is an extremely sensitive approach to measuring thermal fields in fluids. Moreover, the temperature dependence of sound velocity in liquid metals is comparable to the temperature dependence of the speed of light required for accurate interferometric thermal images in transparent fluids. With an array of transducers scanned electronically a map of the thermal field over the chamber could be produced. An alternative approach would be to use the ultrasound analog of the shadowgraph technique. In the optical version, collimated light passes through the fluid, where it is focused or defocused locally by temperature field induced variations of the index of refraction. The resulting image reveals the thermal field through the spatial pattern of light intensity variations. By analogy, an ultrasound plane wave traversing an opaque fluid sample would be also locally focused or defocused depending on the speed of sound variations, giving rise

  16. Thumb ultrasound: Technique and pathologies

    PubMed Central

    Singh, Jatinder P; Kumar, Shwetam; Kathiria, Atman V; Harjai, Rachit; Jawed, Akram; Gupta, Vikas

    2016-01-01

    Ultrasound is ideally suited for the assessment of complex anatomy and pathologies of the thumb. Focused and dynamic thumb ultrasound can provide a rapid real-time diagnosis and can be used for guided treatment in certain clinical situations. We present a simplified approach to scanning technique for thumb-related pathologies and illustrate a spectrum of common and uncommon pathologies encountered. PMID:27857468

  17. Ultrasound-guided synovial biopsy

    PubMed Central

    Sitt, Jacqueline C M; Wong, Priscilla

    2016-01-01

    Ultrasound-guided needle biopsy of synovium is an increasingly performed procedure with a high diagnostic yield. In this review, we discuss the normal synovium, as well as the indications, technique, tissue handling and clinical applications of ultrasound-guided synovial biopsy. PMID:26581578

  18. Addressing Phonological Questions with Ultrasound

    ERIC Educational Resources Information Center

    Davidson, Lisa

    2005-01-01

    Ultrasound can be used to address unresolved questions in phonological theory. To date, some studies have shown that results from ultrasound imaging can shed light on how differences in phonological elements are implemented. Phenomena that have been investigated include transitional schwa, vowel coalescence, and transparent vowels. A study of…

  19. Endoscopic ultrasound in mediastinal tuberculosis

    PubMed Central

    Sharma, Malay; Ecka, Ruth Shifa; Somasundaram, Aravindh; Shoukat, Abid; Kirnake, Vijendra

    2016-01-01

    Background: Tubercular lymphadenitis is the commonest extra pulmonary manifestation in cervical and mediastinal locations. Normal characteristics of lymph nodes (LN) have been described on ultrasonography as well as by Endoscopic Ultrasound. Many ultrasonic features have been described for evaluation of mediastinal lymph nodes. The inter and intraobserver agreement of the endosonographic features have not been uniformly established. Methods and Results: A total of 266 patients underwent endoscopic ultrasound guided fine needle aspiration and 134 cases were diagnosed as mediastinal tuberculosis. The endoscopic ultrasound location and features of these lymph nodes are described. Conclusion: Our series demonstrates the utility of endoscopic ultrasound guided fine needle aspiration as the investigation of choice for diagnosis of mediastinal tuberculosis and also describes various endoscopic ultrasound features of such nodes. PMID:27051097

  20. What's new in urologic ultrasound?

    PubMed Central

    Lal, Anupam; Naranje, Priyanka; Pavunesan, Santhosh Kumar

    2015-01-01

    Ultrasound is an imaging technology that has evolved swiftly and has come a long way since its beginnings. It is a commonly used initial diagnostic imaging modality as it is rapid, effective, portable, relatively inexpensive, and causes no harm to human health. In the last few decades, there have been significant technological improvements in the equipment as well as the development of contrast agents that allowed ultrasound to be even more widely adopted for urologic imaging. Ultrasound is an excellent guidance tool for an array of urologic interventional procedures and also has therapeutic application in the form of high-intensity focused ultrasound (HIFU) for tumor ablation. This article focuses on the recent advances in ultrasound technology and its emerging clinical applications in urology. PMID:26166960

  1. Spectral clustering algorithms for ultrasound image segmentation.

    PubMed

    Archip, Neculai; Rohling, Robert; Cooperberg, Peter; Tahmasebpour, Hamid; Warfield, Simon K

    2005-01-01

    Image segmentation algorithms derived from spectral clustering analysis rely on the eigenvectors of the Laplacian of a weighted graph obtained from the image. The NCut criterion was previously used for image segmentation in supervised manner. We derive a new strategy for unsupervised image segmentation. This article describes an initial investigation to determine the suitability of such segmentation techniques for ultrasound images. The extension of the NCut technique to the unsupervised clustering is first described. The novel segmentation algorithm is then performed on simulated ultrasound images. Tests are also performed on abdominal and fetal images with the segmentation results compared to manual segmentation. Comparisons with the classical NCut algorithm are also presented. Finally, segmentation results on other types of medical images are shown.

  2. Procedural ultrasound in pediatric patients: techniques and tips for accuracy and safety.

    PubMed

    Lin, Sophia

    2016-06-01

    Point-of-care ultrasound is becoming more prevalent in pediatric emergency departments as a critical adjunct to both diagnosis and procedure guidance. It is cost-effective, safe for unstable patients, and easily repeatable as a patient's clinical status changes. Point-of-care ultrasound does not expose the patient to ionizing radiation and may care ultrasound in pediatric emergency medicine is relatively new, the body of literature evaluating its utility is small, but growing. Data from adult emergency medicine, radiology, critical care, and anesthesia evaluating the utility of ultrasound guidance must be extrapolated to pediatric emergency medicine. This issue will review the adult literature and the available pediatric literature comparing ultrasound guidance to more traditional approaches. Methods for using ultrasound guidance to perform various procedures, and the pitfalls associated with each procedure, will also be described.

  3. [An adaptive ultrasound sound speed optimization based on image contrast analysis].

    PubMed

    Li, Xiaoying; Liu, Dongquan

    2011-12-01

    In order to get real time ultrasound images with clear structure and improved contrast, an adaptive ultrasound sound speed optimization method based on image contrast analysis was investigated. It firstly introduced the dynamic beamforming of ultrasound system, as well as the definition of assumed system's sound speed and the true sound speed propagated in tissues the degrade image quality due to their mismatch was also discussed. After given the pixel gray level value based ultrasound image contrast ratio, the basic idea to precisely estimate the true sound speed for real time system sound speed was proposed. Algorithms have been verified both in tissue-mimicking phantoms with known sound speeds and in vivo ultrasound images, compared with other existing method. The testing results showed that this new method not only produced accurate sound speed for ultrasound image optimization, but also finely met the critical computation requirement for real time applications.

  4. Characterization of individual ultrasound microbubble dynamics with a light-scattering system

    PubMed Central

    Hsu, Mark J.; Eghtedari, Mohammad; Goodwin, Andrew P.; Hall, David J.; Mattrey, Robert F.; Esener, Sadik C.

    2011-01-01

    Ultrasound microbubbles are contrast agents used for diagnostic ultrasound imaging and as carriers for noninvasive payload delivery. Understanding the acoustic properties of individual microbubble formulations is important for optimizing the ultrasound imaging parameters for improved image contrast and efficient payload delivery. We report here a practical and simple optical tool for direct real-time characterization of ultrasound contrast microbubble dynamics based on light scattering. Fourier transforms of raw linear and nonlinear acoustic oscillations, and microbubble cavitations are directly recorded. Further, the power of this tool is demonstrated by comparing clinically relevant microbubble cycle-to-cycle dynamics and their corresponding Fourier transforms. PMID:21721823

  5. Linear tracking for 3-D medical ultrasound imaging.

    PubMed

    Huang, Qing-Hua; Yang, Zhao; Hu, Wei; Jin, Lian-Wen; Wei, Gang; Li, Xuelong

    2013-12-01

    As the clinical application grows, there is a rapid technical development of 3-D ultrasound imaging. Compared with 2-D ultrasound imaging, 3-D ultrasound imaging can provide improved qualitative and quantitative information for various clinical applications. In this paper, we proposed a novel tracking method for a freehand 3-D ultrasound imaging system with improved portability, reduced degree of freedom, and cost. We designed a sliding track with a linear position sensor attached, and it transmitted positional data via a wireless communication module based on Bluetooth, resulting in a wireless spatial tracking modality. A traditional 2-D ultrasound probe fixed to the position sensor on the sliding track was used to obtain real-time B-scans, and the positions of the B-scans were simultaneously acquired when moving the probe along the track in a freehand manner. In the experiments, the proposed method was applied to ultrasound phantoms and real human tissues. The results demonstrated that the new system outperformed a previously developed freehand system based on a traditional six-degree-of-freedom spatial sensor in phantom and in vivo studies, indicating its merit in clinical applications for human tissues and organs.

  6. Sialoendoscopy, sialography, and ultrasound: a comparison of diagnostic methods

    PubMed Central

    Pniak, Tomáš; Štrympl, Pavel; Staníková, Lucia; Zeleník, Karol; Matoušek, Petr

    2016-01-01

    Abstract Objective To compare the accuracy of ultrasound, sialography, and sialendoscopy for examining benign salivary gland obstructions. Methods In this prospective study, patients with symptoms of obstruction of the major salivary gland duct system presenting at the ENT Clinic University Hospital, Ostrava, from June 2010 to December 2013 were included. All patients (n=76) underwent ultrasound, sialography, and sialoendoscopy. The signs of sialolithiasis, ductal stenosis, or normal findings were recorded after the examinations. Statistical analysis of the sensitivity and specificity of all the methods was performed, as well as a comparison of the accuracy of each method for different kinds of pathology (sialolithiasis or stenosis). Results The sensitivity of ultrasound, sialography, and sialoendoscopy for sialolithiasis findings were 71.9%, 86.7 %, and 100%, respectively. The sensitivity of sialography and sialoendoscopy for stenosis of the duct was 69.0%, and 100%, respectively. The study showed impossibility of ultrasonic diagnostics of ductal stenosis. The sensitivity of sialoendoscopy for both pathologies was significantly higher than that from ultrasound or sialography (p<0.05). The specificity of sialoendoscopy was significantly higher than that from by ultrasound or sialography (p<0.05). Conclusion Sialoendoscopy was the most accurate method for examination ductal pathology, with significantly higher sensitivity and specificity than by ultrasound or sialography. PMID:28352836

  7. Active Ultrasound Pattern Injection System (AUSPIS) for Interventional Tool Guidance

    PubMed Central

    Guo, Xiaoyu; Kang, Hyun-Jae; Etienne-Cummings, Ralph; Boctor, Emad M.

    2014-01-01

    Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking. PMID:25337784

  8. Clinical workflow for spinal curvature measurement with portable ultrasound

    NASA Astrophysics Data System (ADS)

    Tabanfar, Reza; Yan, Christina; Kempston, Michael; Borschneck, Daniel; Ungi, Tamas; Fichtinger, Gabor

    2016-03-01

    PURPOSE: Spinal curvature monitoring is essential in making treatment decisions in scoliosis. Monitoring entails radiographic examinations, however repeated ionizing radiation exposure has been shown to increase cancer risk. Ultrasound does not emit ionizing radiation and is safer for spinal curvature monitoring. We investigated a clinical sonography protocol and challenges associated with position-tracked ultrasound in spinal curvature measurement in scoliosis. METHODS: Transverse processes were landmarked along each vertebra using tracked ultrasound snapshots. The transverse process angle was used to determine the orientation of each vertebra. We tested our methodology on five patients in a local pediatric scoliosis clinic, comparing ultrasound to radiographic curvature measurements. RESULTS: Despite strong correlation between radiographic and ultrasound curvature angles in phantom studies, we encountered new challenges in the clinical setting. Our main challenge was differentiating transverse processes from ribs and other structures during landmarking. We observed up to 13° angle variability for a single vertebra and a 9.85° +/- 10.81° difference between ultrasound and radiographic Cobb angles for thoracic curvatures. Additionally, we were unable to visualize anatomical landmarks in the lumbar region where soft tissue depth was 25-35mm. In volunteers with large Cobb angles (greater than 40° thoracic and 60° lumbar), we observed spinal protrusions resulting in incomplete probe-skin contact and partial ultrasound images not suitable for landmarking. CONCLUSION: Spinal curvature measurement using tracked ultrasound is viable on phantom spine models. In the clinic, new challenges were encountered which must be resolved before a universal sonography protocol can be developed.

  9. Ultrasound assessment of medial meniscal extrusion: a validation study using MRI as reference standard.

    PubMed

    Nogueira-Barbosa, Marcello H; Gregio-Junior, Everaldo; Lorenzato, Mario M; Guermazi, Ali; Roemer, Frank W; Chagas-Neto, Francisco A; Crema, Michel D

    2015-03-01

    OBJECTIVE. The purpose of this article is to validate both semiquantitative and quantitative ultrasound assessment of medial meniscal extrusion using MRI assessment as the reference standard. SUBJECTS AND METHODS. Ninety-three consecutive patients with chronic knee pain referred for knee MRI were evaluated by ultrasound and MRI on the same day. Two musculoskeletal radiologists assessed meniscal extrusion on ultrasound and MRI separately and independently and graded it semiquantitatively as follows: 0 (< 2 mm), 1 (≥ 2 mm and < 4 mm), and 2 (≥ 4 mm). Agreement between the ultrasound and MRI evaluations was determined using weighted kappa statistics. Intraclass correlation coefficients were used to evaluate agreement using the absolute values of extrusion (quantitative assessment). We further evaluated the diagnostic performance of ultrasound for the detection of medial meniscal extrusion using MRI as the reference standard. RESULTS. For semiquantitative grading, agreement between ultrasound and MRI was moderate for reader 1 (κ = 0.57) and substantial for reader 2 (κ = 0.64). Substantial agreement was found for both readers (intraclass correlation coefficients, 0.73 and 0.70) when comparing quantitative assessment of meniscal extrusion between ultrasound and MRI. Ultrasound showed excellent sensitivity (95% and 96% for each reader) and good specificity (82% and 70% for each reader) in the detection of meniscal extrusion. CONCLUSION. Ultrasound assessment of meniscal extrusion is reliable and can be used for both quantitative and semiquantitative assessment, exhibiting excellent diagnostic performance for the detection of meniscal extrusion compared with MRI.

  10. Endocavity Ultrasound Probe Manipulators

    PubMed Central

    Stoianovici, Dan; Kim, Chunwoo; Schäfer, Felix; Huang, Chien-Ming; Zuo, Yihe; Petrisor, Doru; Han, Misop

    2014-01-01

    We developed two similar structure manipulators for medical endocavity ultrasound probes with 3 and 4 degrees of freedom (DoF). These robots allow scanning with ultrasound for 3-D imaging and enable robot-assisted image-guided procedures. Both robots use remote center of motion kinematics, characteristic of medical robots. The 4-DoF robot provides unrestricted manipulation of the endocavity probe. With the 3-DoF robot the insertion motion of the probe must be adjusted manually, but the device is simpler and may also be used to manipulate external-body probes. The robots enabled a novel surgical approach of using intraoperative image-based navigation during robot-assisted laparoscopic prostatectomy (RALP), performed with concurrent use of two robotic systems (Tandem, T-RALP). Thus far, a clinical trial for evaluation of safety and feasibility has been performed successfully on 46 patients. This paper describes the architecture and design of the robots, the two prototypes, control features related to safety, preclinical experiments, and the T-RALP procedure. PMID:24795525

  11. Accelerated Focused Ultrasound Imaging

    PubMed Central

    White, P. Jason; Thomenius, Kai; Clement, Gregory T.

    2010-01-01

    One of the most, basic trade-offs in ultrasound imaging involves frame rate, depth, and number of lines. Achieving good spatial resolution and coverage requires a large number of lines, leading to decreases in frame rate. An even more serious imaging challenge occurs with imaging modes involving spatial compounding and 3-D/4-D imaging, which are severely limited by the slow speed of sound in tissue. The present work can overcome these traditional limitations, making ultrasound imaging many-fold faster. By emitting several beams at once, and by separating the resulting overlapped signals through spatial and temporal processing, spatial resolution and/or coverage can be increased by many-fold while leaving frame rates unaffected. The proposed approach can also be extended to imaging strategies that do not involve transmit beamforming, such as synthetic aperture imaging. Simulated and experimental results are presented where imaging speed is improved by up to 32-fold, with little impact on image quality. Object complexity has little impact on the method’s performance, and data from biological systems can readily be handled. The present work may open the door to novel multiplexed and/or multidimensional protocols considered impractical today. PMID:20040398

  12. Ultrasound in cardiac trauma.

    PubMed

    Saranteas, Theodosios; Mavrogenis, Andreas F; Mandila, Christina; Poularas, John; Panou, Fotios

    2017-04-01

    In the perioperative period, the emergency department or the intensive care unit accurate assessment of variable chest pain requires meticulous knowledge, diagnostic skills, and suitable usage of various diagnostic modalities. In addition, in polytrauma patients, cardiac injury including aortic dissection, pulmonary embolism, acute myocardial infarction, and pericardial effusion should be immediately revealed and treated. In these patients, arrhythmias, mainly tachycardia, cardiac murmurs, or hypotension must alert physicians to suspect cardiovascular trauma, which would potentially be life threatening. Ultrasound of the heart using transthoracic and transesophageal echocardiography are valuable diagnostic tools that can be used interchangeably in conjunction with other modalities such as the electrocardiogram and computed tomography for the diagnosis of cardiovascular abnormalities in trauma patients. Although ultrasound of the heart is often underused in the setting of trauma, it does have the advantages of being easily accessible, noninvasive, and rapid bedside assessment tool. This review article aims to analyze the potential cardiac injuries in trauma patients, and to provide an elaborate description of the role of echocardiography for their accurate diagnosis.

  13. Endocavity Ultrasound Probe Manipulators.

    PubMed

    Stoianovici, Dan; Kim, Chunwoo; Schäfer, Felix; Huang, Chien-Ming; Zuo, Yihe; Petrisor, Doru; Han, Misop

    2013-06-01

    We developed two similar structure manipulators for medical endocavity ultrasound probes with 3 and 4 degrees of freedom (DoF). These robots allow scanning with ultrasound for 3-D imaging and enable robot-assisted image-guided procedures. Both robots use remote center of motion kinematics, characteristic of medical robots. The 4-DoF robot provides unrestricted manipulation of the endocavity probe. With the 3-DoF robot the insertion motion of the probe must be adjusted manually, but the device is simpler and may also be used to manipulate external-body probes. The robots enabled a novel surgical approach of using intraoperative image-based navigation during robot-assisted laparoscopic prostatectomy (RALP), performed with concurrent use of two robotic systems (Tandem, T-RALP). Thus far, a clinical trial for evaluation of safety and feasibility has been performed successfully on 46 patients. This paper describes the architecture and design of the robots, the two prototypes, control features related to safety, preclinical experiments, and the T-RALP procedure.

  14. Ultrasound pretreatment for enhanced biogas production from olive mill wastewater.

    PubMed

    Oz, Nilgun Ayman; Uzun, Alev Cagla

    2015-01-01

    This study investigates applicability of low frequency ultrasound technology to olive mill wastewaters (OMWs) as a pretreatment step prior to anaerobic batch reactors to improve biogas production and methane yield. OMWs originating from three phase processes are characterized with high organic content and complex nature. The treatment of the wastewater is problematic and alternative treatment options should be investigated. In the first part of the study, OMW samples were subjected to ultrasound at a frequency of 20kHz with applied powers varying between 50 and 100W under temperature controlled conditions for different time periods in order to determine the most effective sonication conditions. The level of organic matter solubilization at ultrasound experiments was assessed by calculating the ratio of soluble chemical oxygen demand/total chemical oxygen demand (SCOD/TCOD). The results revealed that the optimum ultrasonic condition for diluted OMW is 20kHz, 0.4W/mL for 10min. The application of ultrasound to OMW increased SCOD/TCOD ratio from 0.59 to 0.79. Statistical analysis (Friedman's tests) show that ultrasound was significantly effective on diluted OMW (p<0.05) in terms of SCOD parameter, but not for raw OMW (p>0.05). For raw OMW, this increase has been found to be limited due to high concentration of suspended solids (SS). In the second part of the study, biogas and methane production rates of anaerobic batch reactor fed with the ultrasound pretreated OMW samples were compared with the results of control reactor fed with untreated OMW in order to determine the effect of sonication. A nonparametric statistical procedure, Mann-Whitney U test, was used to compare biogas and methane production from anaerobic batch reactors for control and ultrasound pretreated samples. Results showed that application of low frequency ultrasound to OMW significantly improved both biogas and methane production in anaerobic batch reactor fed with the wastewater (p<0.05). Anaerobic

  15. Determining Directions of Ultrasound in Solids

    NASA Technical Reports Server (NTRS)

    Generazio, Edward R.; Roth, Don J.

    1987-01-01

    Ultrasound shadows cast by grooves. Improved method for determining direction of ultrasound in materials is shadow method using Scanning laser acoustic microscopy (SLAM). Direction of ultrasound calculated from dimensions of groove and portion of surface groove shields from ultrasound. Method has variety of applications in nontraditional quality-control applications.

  16. Resolution enhancement in medical ultrasound imaging

    PubMed Central

    Ploquin, Marie; Basarab, Adrian; Kouamé, Denis

    2015-01-01

    Abstract. Image resolution enhancement is a problem of considerable interest in all medical imaging modalities. Unlike general purpose imaging or video processing, for a very long time, medical image resolution enhancement has been based on optimization of the imaging devices. Although some recent works purport to deal with image postprocessing, much remains to be done regarding medical image enhancement via postprocessing, especially in ultrasound imaging. We face a resolution improvement issue in the case of medical ultrasound imaging. We propose to investigate this problem using multidimensional autoregressive (AR) models. Noting that the estimation of the envelope of an ultrasound radio frequency (RF) signal is very similar to the estimation of classical Fourier-based power spectrum estimation, we theoretically show that a domain change and a multidimensional AR model can be used to achieve super-resolution in ultrasound imaging provided the order is estimated correctly. Here, this is done by means of a technique that simultaneously estimates the order and the parameters of a multidimensional model using relevant regression matrix factorization. Doing so, the proposed method specifically fits ultrasound imaging and provides an estimated envelope. Moreover, an expression that links the theoretical image resolution to both the image acquisition features (such as the point spread function) and a postprocessing feature (the AR model) order is derived. The overall contribution of this work is threefold. First, it allows for automatic resolution improvement. Through a simple model and without any specific manual algorithmic parameter tuning, as is used in common methods, the proposed technique simply and exclusively uses the ultrasound RF signal as input and provides the improved B-mode as output. Second, it allows for the a priori prediction of the improvement in resolution via the knowledge of the parametric model order before actual processing. Finally, to achieve

  17. Resolution enhancement in medical ultrasound imaging.

    PubMed

    Ploquin, Marie; Basarab, Adrian; Kouamé, Denis

    2015-01-01

    Image resolution enhancement is a problem of considerable interest in all medical imaging modalities. Unlike general purpose imaging or video processing, for a very long time, medical image resolution enhancement has been based on optimization of the imaging devices. Although some recent works purport to deal with image postprocessing, much remains to be done regarding medical image enhancement via postprocessing, especially in ultrasound imaging. We face a resolution improvement issue in the case of medical ultrasound imaging. We propose to investigate this problem using multidimensional autoregressive (AR) models. Noting that the estimation of the envelope of an ultrasound radio frequency (RF) signal is very similar to the estimation of classical Fourier-based power spectrum estimation, we theoretically show that a domain change and a multidimensional AR model can be used to achieve super-resolution in ultrasound imaging provided the order is estimated correctly. Here, this is done by means of a technique that simultaneously estimates the order and the parameters of a multidimensional model using relevant regression matrix factorization. Doing so, the proposed method specifically fits ultrasound imaging and provides an estimated envelope. Moreover, an expression that links the theoretical image resolution to both the image acquisition features (such as the point spread function) and a postprocessing feature (the AR model) order is derived. The overall contribution of this work is threefold. First, it allows for automatic resolution improvement. Through a simple model and without any specific manual algorithmic parameter tuning, as is used in common methods, the proposed technique simply and exclusively uses the ultrasound RF signal as input and provides the improved B-mode as output. Second, it allows for the a priori prediction of the improvement in resolution via the knowledge of the parametric model order before actual processing. Finally, to achieve the

  18. Enzymolysis kinetics and structural characteristics of rice protein with energy-gathered ultrasound and ultrasound assisted alkali pretreatments.

    PubMed

    Li, Suyun; Yang, Xue; Zhang, Yanyan; Ma, Haile; Qu, Wenjuan; Ye, Xiaofei; Muatasim, Rahma; Oladejo, Ayobami Olayemi

    2016-07-01

    This research investigated the structural characteristics and enzymolysis kinetics of rice protein which was pretreated by energy-gathered ultrasound and ultrasound assisted alkali. The structural characteristics of rice protein before and after the pretreatment were performed with surface hydrophobicity and Fourier transform infrared (FTIR). There was an increase in the intensity of fluorescence spectrum and changes in functional groups after the pretreatment on rice protein compared with the control (without ultrasound and ultrasound assisted alkali processed), thus significantly enhancing efficiency of the enzymatic hydrolysis. A simplified kinetic equation for the enzymolysis model with the impeded reaction of enzyme was deduced to successfully describe the enzymatic hydrolysis of rice protein by different pretreatments. The initial observed rate constants (Kin,0) as well as ineffective coefficients (kimp) were proposed and obtained based on the experimental observation. The results showed that the parameter of kin,0 increased after ultrasound and ultrasound assisted alkali pretreatments, which proved the effects of the pretreatments on the substrate enhancing the enzymolysis process and had relation to the structure changes of the pretreatments on the substrate. Furthermore, the applicability of the simplified model was demonstrated by the enzymatic hydrolysis process for other materials.

  19. Reflections on ultrasound image analysis.

    PubMed

    Alison Noble, J

    2016-10-01

    Ultrasound (US) image analysis has advanced considerably in twenty years. Progress in ultrasound image analysis has always been fundamental to the advancement of image-guided interventions research due to the real-time acquisition capability of ultrasound and this has remained true over the two decades. But in quantitative ultrasound image analysis - which takes US images and turns them into more meaningful clinical information - thinking has perhaps more fundamentally changed. From roots as a poor cousin to Computed Tomography (CT) and Magnetic Resonance (MR) image analysis, both of which have richer anatomical definition and thus were better suited to the earlier eras of medical image analysis which were dominated by model-based methods, ultrasound image analysis has now entered an exciting new era, assisted by advances in machine learning and the growing clinical and commercial interest in employing low-cost portable ultrasound devices outside traditional hospital-based clinical settings. This short article provides a perspective on this change, and highlights some challenges ahead and potential opportunities in ultrasound image analysis which may both have high impact on healthcare delivery worldwide in the future but may also, perhaps, take the subject further away from CT and MR image analysis research with time.

  20. Unpowered wireless ultrasound tomography system

    NASA Astrophysics Data System (ADS)

    Zahedi, Farshad; Huang, Haiying

    2016-04-01

    In this paper, an unpowered wireless ultrasound tomography system is presented. The system consists of two subsystems; the wireless interrogation unit (WIU) and three wireless nodes installed on the structure. Each node is designed to work in generation and sensing modes, but operates at a specific microwave frequency. Wireless transmission of the ultrasound signals between the WIU and the wireless nodes is achieved by converting ultrasound signals to microwave signals and vice versa, using a microwave carrier signal. In the generation mode, both a carrier signal and an ultrasound modulated microwave signal are transmitted to the sensor nodes. Only the node whose operating frequency matches the carrier signal will receive these signals and demodulate them to recover the original ultrasound signal. In the sensing mode, a microwave carrier signal with two different frequency components matching the operating frequencies of the sensor nodes is broadcasted by the WIU. The sensor nodes, in turn, receive the corresponding carrier signals, modulate it with the ultrasound sensing signal, and wirelessly transmit the modulated signal back to the WIU. The demodulation of the sensing signals is performed in the WIU using a digital signal processing. Implementing a software receiver significantly reduces the complexity and the cost of the WIU. A wireless ultrasound tomography system is realized by interchanging the carrier frequencies so that the wireless transducers can take turn to serve as the actuator and sensors.

  1. Droplets, Bubbles and Ultrasound Interactions.

    PubMed

    Shpak, Oleksandr; Verweij, Martin; de Jong, Nico; Versluis, Michel

    2016-01-01

    The interaction of droplets and bubbles with ultrasound has been studied extensively in the last 25 years. Microbubbles are broadly used in diagnostic and therapeutic medical applications, for instance, as ultrasound contrast agents. They have a similar size as red blood cells, and thus are able to circulate within blood vessels. Perfluorocarbon liquid droplets can be a potential new generation of microbubble agents as ultrasound can trigger their conversion into gas bubbles. Prior to activation, they are at least five times smaller in diameter than the resulting bubbles. Together with the violent nature of the phase-transition, the droplets can be used for local drug delivery, embolotherapy, HIFU enhancement and tumor imaging. Here we explain the basics of bubble dynamics, described by the Rayleigh-Plesset equation, bubble resonance frequency, damping and quality factor. We show the elegant calculation of the above characteristics for the case of small amplitude oscillations by linearizing the equations. The effect and importance of a bubble coating and effective surface tension are also discussed. We give the main characteristics of the power spectrum of bubble oscillations. Preceding bubble dynamics, ultrasound propagation is introduced. We explain the speed of sound, nonlinearity and attenuation terms. We examine bubble ultrasound scattering and how it depends on the wave-shape of the incident wave. Finally, we introduce droplet interaction with ultrasound. We elucidate the ultrasound-focusing concept within a droplets sphere, droplet shaking due to media compressibility and droplet phase-conversion dynamics.

  2. [Ultrasound for peripheral neural block].

    PubMed

    Kefalianakis, F

    2005-03-01

    Ultrasound is well established in medicine. Unfortunately, ultrasound is still rarely used in the area of anesthesia. The purpose of the article is to illustrate the possibilities and limitations of ultrasound in regional anesthesia. The basic principles of ultrasound are the piezoelectric effect and the behaviour of acoustic waveforms in human tissue. Ultrasound imaging in medicine uses high frequency pulses of sound waves (2.5-10 MHz). The following images are built up from the reflected sounds. The ultrasound devices used in regional anesthesia (commonly by 10 MHz) deliver a two-dimensional view. The main step for a successful regional anaesthesia is to identify the exact position of the nerve. In addition, specific surface landmarks and the use of peripheral nerve stimulator help to detect the correct position of the needle. Nerves are demonstrated as an composition of hyperechogenic (white) and hypoechogenic (black) areas. The surrounding hyperechogenic parts are epi- and perineurium, the dark hypoechogenic part is the neural tissue. The composition of peripheral nerves are always similar, but the quantities of each part, of surrounding perineurium and nerval structures, differ. Further the imaging of nerves is significantly influenced by the angle of beam to the nerve and the surrounding anatomic structures. Only experience and correct interpretation make the ultrasound a valid method in clinical practice. Correct interpretation has to be learned by standardized education. Three examples of peripheral nerve blocks are described. The detection of nerves and the visualization of the correct spread of local anesthetics to the nerves are the main principles of effective ultrasound-guided regional anesthesia, whereas closest proximity of the needle to the target nerve is not necessary. The described examples of ultrasound guidance for nerval block illustrates the specific procedures with reduced probability of nerval irritation, high success and low rate of

  3. Value of Ultrasound in Rheumatologic Diseases

    PubMed Central

    Kang, Taeyoung; Horton, Laura; Emery, Paul

    2013-01-01

    The use of musculoskeletal ultrasound in rheumatology clinical practice has rapidly increased over the past decade. Ultrasound has enabled rheumatologists to diagnose, prognosticate and monitor disease outcome. Although international standardization remains a concern still, the use of ultrasound in rheumatology is expected to grow further as costs fall and the opportunity to train in the technique improves. We present a review of value of ultrasound, focusing on major applications of ultrasound in rheumatologic diseases. PMID:23580002

  4. WE-B-210-02: The Advent of Ultrafast Imaging in Biomedical Ultrasound

    SciTech Connect

    Tanter, M.

    2015-06-15

    spatial and temporal resolution compared to fMRI. Combined with contrast agents, our group demonstrated that Ultrafast Ultrasound Localization could provide a first in vivo and non invasive imaging modality at microscopic scales deep into organs. Many of these ultrafast modes should lead to major improvements in ultrasound screening, diagnosis, and therapeutic monitoring. Learning Objectives: Achieve familiarity with recent advances in ultrafast ultrasound imaging technology. Develop an understanding of potential applications of ultrafast ultrasound imaging for diagnosis and therapeutic monitoring. Dr. Tanter is a co-founder of Supersonic Imagine,a French company positioned in the field of medical ultrasound imaging and therapy.

  5. [Ultrasound of the urinary system].

    PubMed

    Segura-Grau, A; Herzog, R; Díaz-Rodriguez, N; Segura-Cabral, J M

    2016-09-01

    Ultrasound techniques are able to provide a fairly complete examination of the urinary system, achieving a high sensitivity in relevant-pathology detection, especially in the kidney, bladder and prostate. Early detection of pathologies such as tumors or urinary tract obstructions, sometimes even before their clinical manifestation, has improved their management and prognosis in many cases. This, added to its low cost and harmlessness, makes ultrasound ideal for early approaches and follow-up of a wide number of urinary system pathologies. In this article, the ultrasound characteristics of the main urinary system pathologies that can be diagnosed by this technique, are reviewed.

  6. Neuromuscular ultrasound of cranial nerves.

    PubMed

    Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

    2015-04-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.

  7. Ultrasound strain imaging using Barker code

    NASA Astrophysics Data System (ADS)

    Peng, Hui; Tie, Juhong; Guo, Dequan

    2017-01-01

    Ultrasound strain imaging is showing promise as a new way of imaging soft tissue elasticity in order to help clinicians detect lesions or cancers in tissues. In this paper, Barker code is applied to strain imaging to improve its quality. Barker code as a coded excitation signal can be used to improve the echo signal-to-noise ratio (eSNR) in ultrasound imaging system. For the Baker code of length 13, the sidelobe level of the matched filter output is -22dB, which is unacceptable for ultrasound strain imaging, because high sidelobe level will cause high decorrelation noise. Instead of using the conventional matched filter, we use the Wiener filter to decode the Barker-coded echo signal to suppress the range sidelobes. We also compare the performance of Barker code and the conventional short pulse in simulation method. The simulation results demonstrate that the performance of the Wiener filter is much better than the matched filter, and Baker code achieves higher elastographic signal-to-noise ratio (SNRe) than the short pulse in low eSNR or great depth conditions due to the increased eSNR with it.

  8. Superhydrophobic silica nanoparticles as ultrasound contrast agents.

    PubMed

    Jin, Qiaofeng; Lin, Chih-Yu; Kang, Shih-Tsung; Chang, Yuan-Chih; Zheng, Hairong; Yang, Chia-Min; Yeh, Chih-Kuang

    2017-05-01

    Microbubbles have been widely studied as ultrasound contrast agents for diagnosis and as drug/gene carriers for therapy. However, their size and stability (lifetime of 5-12min) limited their applications. The development of stable nanoscale ultrasound contrast agents would therefore benefit both. Generating bubbles persistently in situ would be one of the promising solutions to the problem of short lifetime. We hypothesized that bubbles could be generated in situ by providing stable air nuclei since it has been found that the interfacial nanobubbles on a hydrophobic surface have a much longer lifetime (orders of days). Mesoporous silica nanoparticles (MSNs) with large surface areas and different levels of hydrophobicity were prepared to test our hypothesis. It is clear that the superhydrophobic and porous nanoparticles exhibited a significant and strong contrast intensity compared with other nanoparticles. The bubbles generated from superhydrophobic nanoparticles sustained for at least 30min at a MI of 1.0, while lipid microbubble lasted for about 5min at the same settings. In summary MSNs have been transformed into reliable bubble precursors by making simple superhydrophobic modification, and made into a promising contrast agent with the potentials to serve as theranostic agents that are sensitive to ultrasound stimulation.

  9. Heating of fetal bone by diagnostic ultrasound

    NASA Astrophysics Data System (ADS)

    Doody, Claire

    Most pregnant women in the Western world undergo an ultrasound examination and so it is important to ensure that exposure of the embryo or fetus does not produce unwanted effects. It is known that ultrasound can heat tissue, especially bone, and so this thesis explores the degree to which fetal bone might be heated during a pulsed Doppler examination. This is done both by carrying out measurements and by developing computer models. Thermal measurements on human fetal thoracic vertebrae of gestational age ranging from 14 to 39 weeks are reported. The bone samples were insonated in vitro with an ultrasound beam which had power and intensity values typical of those from a clinical scanner operating in pulsed Doppler mode. Temperature rises ranging from 0.6°C to 1.8°C were observed after five minutes, with approximately 75% of the temperature rise occurring in the first minute. Two approaches to computer modelling are described. These are the heated disc technique, which is commonly used to model the temperature rise generated by an ultrasound beam, and finite element modelling, a more general approach used to obtain solutions to differential equations. The degree to which our limited knowledge of the properties of fetal tissue affect our ability to make accurate predictions of in vivo heating is explored. It is shown that the present uncertainty in the value of the thermal conductivity and attenuation coefficient of fetal bone can lead to significant uncertainty in predictions of heating. The degree to which the simplifications inherent in the heated disc model affect the results will also be discussed. The results from the models are compared with the experimental measurements in order to estimate the attenuation coefficient of the bone.

  10. Resonant ultrasound spectroscopy

    DOEpatents

    Migliori, Albert

    1991-01-01

    A resonant ultrasound spectroscopy method provides a unique characterization of an object for use in distinguishing similar objects having physical differences greater than a predetermined tolerance. A resonant response spectrum is obtained for a reference object by placing excitation and detection transducers at any accessible location on the object. The spectrum is analyzed to determine the number of resonant response peaks in a predetermined frequency interval. The distribution of the resonance frequencies is then characterized in a manner effective to form a unique signature of the object. In one characterization, a small frequency interval is defined and stepped though the spectrum frequency range. Subsequent objects are similarly characterized where the characterizations serve as signatures effective to distinguish objects that differ from the reference object by more than the predetermined tolerance.

  11. Ultrasound guided fluorescence tomography

    NASA Astrophysics Data System (ADS)

    Li, Baoqiang; Lesage, Frederic

    2012-10-01

    In this study, a hybrid-model imaging system combining fluorescence and ultrasound (US) was investigated with the motivation of providing structural priors towards improvement of fluorescence reconstruction. A single element transducer was scanned over the sample for anatomy. In the fluorescence part, a laser source was scanned over the sample with the emission received by an EMCCD camera. Synchronization was achieved by a pair of motorized linear stages. Structural information was derived from the US images and a profilometry and used to constrain reconstruction. In the reconstruction, we employed a GPU-based Monte Carlo simulation for forward modeling and a pattern-based method to take advantage of the huge dataset for the inverse problem. Performance of this system was validated with two phantoms with fluorophore inclusions. The results indicated that the fluorophore distribution could be accurately reconstructed. And the system has a potential for the future in-vivo study.

  12. Therapeutic endoscopic ultrasound

    PubMed Central

    Venkatachalapathy, Suresh; Nayar, Manu K

    2017-01-01

    Endoscopic ultrasound (EUS) is now firmly established as one of the essential tools for diagnosis in most gastrointestinal MDTs across the UK. However, the ability to provide therapy with EUS has resulted in a significant impact on the management of the patients. These include drainage of peripancreatic collections, EUS-guided endoscopic retrograde cholangiopancreatogram, EUS-guided coeliac plexus blocks, etc. The rapid development of this area in endoscopy is a combination of newer tools and increasing expertise by endosonographers to push the boundaries of intervention with EUS. However, the indications are limited and we are at the start of the learning curve for these high-risk procedures. These therapies should, therefore, be confined to centres with a robust multidisciplinary team, including interventional endoscopists, radiologists and surgeons. PMID:28261439

  13. Ultrasound contrast agents

    PubMed Central

    Ignee, Andre; Atkinson, Nathan S. S.; Schuessler, Gudrun; Dietrich, Christoph F.

    2016-01-01

    Endoscopic ultrasound (EUS) plays an important role in imaging of the mediastinum and abdominal organs. Since the introduction of US contrast agents (UCA) for transabdominal US, attempts have been made to apply contrast-enhanced US techniques also to EUS. Since 2003, specific contrast-enhanced imaging was possible using EUS. Important studies have been published regarding contrast-enhanced EUS and the characterization of focal pancreatic lesions, lymph nodes, and subepithelial tumors. In this manuscript, we describe the relevant UCA, their application, and specific image acquisition as well as the principles of image tissue characterization using contrast-enhanced EUS. Safety issues, potential future developments, and EUS-specific issues are reviewed. PMID:27824024

  14. Cognitive load imposed by ultrasound-facilitated teaching does not adversely affect gross anatomy learning outcomes.

    PubMed

    Jamniczky, Heather A; Cotton, Darrel; Paget, Michael; Ramji, Qahir; Lenz, Ryan; McLaughlin, Kevin; Coderre, Sylvain; Ma, Irene W Y

    2017-03-01

    Ultrasonography is increasingly used in medical education, but its impact on learning outcomes is unclear. Adding ultrasound may facilitate learning, but may also potentially overwhelm novice learners. Based upon the framework of cognitive load theory, this study seeks to evaluate the relationship between cognitive load associated with using ultrasound and learning outcomes. The use of ultrasound was hypothesized to facilitate learning in anatomy for 161 novice first-year medical students. Using linear regression analyses, the relationship between reported cognitive load on using ultrasound and learning outcomes as measured by anatomy laboratory examination scores four weeks after ultrasound-guided anatomy training was evaluated in consenting students. Second anatomy examination scores of students who were taught anatomy with ultrasound were compared with historical controls (those not taught with ultrasound). Ultrasound's perceived utility for learning was measured on a five-point scale. Cognitive load on using ultrasound was measured on a nine-point scale. Primary outcome was the laboratory examination score (60 questions). Learners found ultrasound useful for learning. Weighted factor score on "image interpretation" was negatively, but insignificantly, associated with examination scores [F (1,135) = 0.28, beta = -0.22; P = 0.61]. Weighted factor score on "basic knobology" was positively and insignificantly associated with scores; [F (1,138) = 0.27, beta = 0.42; P = 0.60]. Cohorts exposed to ultrasound had significantly higher scores than historical controls (82.4% ± SD 8.6% vs. 78.8% ± 8.5%, Cohen's d = 0.41, P < 0.001). Using ultrasound to teach anatomy does not negatively impact learning and may improve learning outcomes. Anat Sci Educ 10: 144-151. © 2016 American Association of Anatomists.

  15. Ultrasound-guided central vascular interventions, comments on the European Federation of Societies for Ultrasound in Medicine and Biology guidelines on interventional ultrasound

    PubMed Central

    Horn, Rudolf; Morf, Susanne; Chiorean, Liliana; Dong, Yi; Cui, Xin-Wu; Atkinson, Nathan S. S.; Jenssen, Christian

    2016-01-01

    Central venous access has traditionally been performed on the basis of designated anatomical landmarks. However, due to patients’ individual anatomy and vessel pathology and depending on individual operators’ skill, this landmark approach is associated with a significant failure rate and complication risk. There is substantial evidence demonstrating significant improvement in effectiveness and safety of vascular access by realtime ultrasound (US)-guidance, as compared to the anatomical landmark-guided approach. This review comments on the evidence-based recommendations on US-guided vascular access which have been published recently within the framework of Guidelines on Interventional Ultrasound (InVUS) of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) from a clinical practice point of view. PMID:27747022

  16. Skin Ultrasound in Kaposi Sarcoma.

    PubMed

    Carrascosa, R; Alfageme, F; Roustán, G; Suarez, M D

    2016-05-01

    The use of ultrasound imaging has recently been increasing in numerous dermatologic diseases. This noninvasive technique provides additional details on the structure and vascularization of skin lesions. Kaposi sarcoma is a vascular tumor that typically arises in the skin and mucosas. It can spread to lymph nodes and internal organs. We performed B-mode and color Doppler ultrasound studies in 3 patients with a clinical diagnosis of Kaposi sarcoma confirmed by histological examination. We found differences in the ultrasound pattern between nodular and plaque lesions, in both B-mode and color Doppler. We believe that skin ultrasound imaging could be a useful technique for studying cutaneous Kaposi sarcoma, providing additional information on the structural and vascular characteristics of the lesion.

  17. Ultrasound-modulated bioluminescence tomography

    NASA Astrophysics Data System (ADS)

    Bal, Guillaume; Schotland, John C.

    2014-03-01

    We propose a method to reconstruct the density of a luminescent source in a highly scattering medium from ultrasound-modulated optical measurements. Our approach is based on the solution to a hybrid inverse source problem for the diffusion equation.

  18. Ultrasound-Guided Breast Biopsy

    MedlinePlus

    ... Breast Biopsy An ultrasound-guided breast biopsy uses sound waves to help locate a lump or abnormality ... exam. The transducer sends out inaudible, high—frequency sound waves into the body and then listens for ...

  19. Volume flow in arteriovenous fistulas using vector velocity ultrasound.

    PubMed

    Hansen, Peter Møller; Olesen, Jacob Bjerring; Pihl, Michael Johannes; Lange, Theis; Heerwagen, Søren; Pedersen, Mads Møller; Rix, Marianne; Lönn, Lars; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2014-11-01

    Volume flow in arteriovenous fistulas for hemodialysis was measured using the angle-independent ultrasound technique Vector Flow Imaging and compared with flow measurements using the ultrasound dilution technique during dialysis. Using an UltraView 800 ultrasound scanner (BK Medical, Herlev, Denmark) with a linear transducer, 20 arteriovenous fistulas were scanned directly on the most superficial part of the fistula just before dialysis. Vector Flow Imaging volume flow was estimated with two different approaches, using the maximum and the average flow velocities detected in the fistula. Flow was estimated to be 242 mL/min and 404 mL/min lower than the ultrasound dilution technique estimate, depending on the approach. The standard deviations of the two Vector Flow Imaging approaches were 175.9 mL/min and 164.8 mL/min compared with a standard deviation of 136.9 mL/min using the ultrasound dilution technique. The study supports that Vector Flow Imaging is applicable for volume flow measurements.

  20. [Ultrasound of spleen and retroperitoneum].

    PubMed

    Salcedo Joven, I; Segura-Grau, A; Díaz Rodríguez, N; Segura-Cabral, J M

    2016-09-01

    Ultrasound provides data of extremely great value when studying spleen pathology, being diagnostic in splenomegaly and splenic trauma, as well as offering a good approach to the diagnosis of both benign and malignant focal pathology, particularly lymphoma. However, for the evaluation of adrenal and retroperitoneal diseases, other techniques such as CT or MRI are more suitable, even though ultrasound is still an excellent screening and monitoring method, as well as being useful in non-invasive therapeutic approaches.

  1. Power ultrasound-assisted cleaner leather dyeing technique: influence of process parameters.

    PubMed

    Sivakumar, Venkatasubramanian; Rao, Paruchuri Gangadhar

    2004-03-01

    The application of power ultrasound to leather processing has a significant role in the concept of "clean technology" for leather production. The effect of power ultrasound in leather dyeing has been compared with dyeing in the absence of ultrasound and conventional drumming. The power ultrasound source used in these experiments was ultrasonic cleaner (150 W and 33 kHz). The effect of various process parameters such as amount of dye offer, temperature, and type of dye has been experimentally found out. The effect of presonication of dye solution as well as leather has been studied. Experiments at ultrasonic bath temperature were carried out to find out the combined thermal as well as stirring effects of ultrasound. Dyeing in the presence of ultrasound affords about 37.5 (1.8 times) difference as increase in % dye exhaustion or about 50% decrease in the time required for dyeing compared to dyeing in the absence of ultrasound for 4% acid red dye. About 29 (1.55 times) increase in % dye exhaustion or 30% reduction in time required for dyeing was observed using ultrasound at stationary condition compared with conventional dynamic drumming conditions. The effect of ultrasound at constant temperature conditions with a control experiment has also been studied. The dye exhaustion increases as the temperature increases (30-60 degrees C) and better results are observed at higher temperature due to the use of ultrasound. Presonication of dye solution or crust leather prior to the dyeing process has no significant improvement in dye exhaustion, suggesting ultrasound effect is realized when it is applied during the dyeing process. The results indicate that 1697 and 1416 ppm of dye can be reduced in the spent liquor due to the use of ultrasound for acid red (for 100 min) and acid black (for 3 h) dyes, respectively, thereby reducing the pollution load in the effluent stream. The color yield of the leather as inferred from the reflectance measurement indicates that dye offer can

  2. Potential use of ultrasound in creating transmyocardial channels.

    PubMed

    Yamamoto, S; Kohmoto, T; Kino, K; Yoshida, H; Sano, S

    2001-06-01

    Although the mechanisms of the clinical benefits of transmyocardial laser revascularization (TMLR) are considered to be angiogenesis with increased perfusion, denervation and placebo effect, it is unknown whether laser energy is a prerequisite in obtaining these beneficial effects. The present study investigated whether it is possible to create transmyocardial channels and induce angiogenesis by ultrasound. Myocardium was penetrated with an ultrasonically activated surgical blade by advancing the blade tip perpendicularly to the left ventricular free wall of the beating heart of 6 mongrel dogs. The power of ultrasound was set at either the lowest or highest of the system. The animals were killed 30 min (acute; n=3) and 2 weeks (chronic; n=3) after channel creation. Holmium:YAG laser, which is currently used for clinical TMLR, was used to create myocardial channels in 4 other dogs, which were also killed 30 min (n=2) and 2 weeks (n=2) after channel creation. The areas of acute channel core, acute thermal damage and chronic fibrosis were compared between the laser and ultrasound channels by Masson's trichrome stain. Factor VIII and proliferating cell nuclear antigen (PCNA) immunostaining were carried out on the samples obtained from chronic animals. The density of vessels and that of proliferating vascular endothelial cells and vascular smooth muscle cells around the channels were measured. The area of acute core was larger in the lowest and highest outputs of ultrasound than in laser channels (0.78+/-0.09, 1.0+/-0.12 vs 0.38+/-0.04 mm2; p<0.01). The area of acute damage in both laser and the highest output of ultrasound channels was greater than in the channels produced by the lowest output of ultrasound (4.43+/-0.28, 4.63+/-0.44 vs 2.90+/-0.29 mm2; p<0.01). The ratio of acute damage area to acute core area was greater in laser channels than in either type of ultrasound channel (16.86+/-1.66 vs 6.04+/-0.67, 7.86+/-1.07; p<0.01) and the area of chronic fibrosis was

  3. Different Learning Curves for Axillary Brachial Plexus Block: Ultrasound Guidance versus Nerve Stimulation

    PubMed Central

    Luyet, C.; Schüpfer, G.; Wipfli, M.; Greif, R.; Luginbühl, M.; Eichenberger, U.

    2010-01-01

    Little is known about the learning of the skills needed to perform ultrasound- or nerve stimulator-guided peripheral nerve blocks. The aim of this study was to compare the learning curves of residents trained in ultrasound guidance versus residents trained in nerve stimulation for axillary brachial plexus block. Ten residents with no previous experience with using ultrasound received ultrasound training and another ten residents with no previous experience with using nerve stimulation received nerve stimulation training. The novices' learning curves were generated by retrospective data analysis out of our electronic anaesthesia database. Individual success rates were pooled, and the institutional learning curve was calculated using a bootstrapping technique in combination with a Monte Carlo simulation procedure. The skills required to perform successful ultrasound-guided axillary brachial plexus block can be learnt faster and lead to a higher final success rate compared to nerve stimulator-guided axillary brachial plexus block. PMID:21318138

  4. [Cervical cancer staging - preoperative assessment of tumor extent (a review of the most recent ultrasound studies)].

    PubMed

    Fischerová, D

    2014-12-01

    For treatment planning of cervical cancer it is necessary preoperatively to determine the presence and size of residual tumour after the biopsy, the tumour topography within the cervix and the parametrial and lymph node status. According to current data, ultrasound is comparably accurate with magnetic resonance imaging in view of tumour presence and local extent assessment. Ultrasound, if compared with the magnetic resonance imaging, does not have known contraindications and it is a broadly available diagnostic test. Currently no advanced imaging technique exists that can reliably detect infiltrated lymph nodes in the clinically early stage of the disease, as it often manifests as micrometastatic involvement in non-enlarged lymph nodes. The sensitivity of lymph node detection using ultrasound in the early stage is around 40%, but the specificity is high (96%). For daily practice, this means that a negative ultrasound finding should be always verified by surgical staging based on systematic lymphadenectomy, while positive ultrasound finding usually changes the treatment strategy.

  5. Ultrasound-Mediated Polymeric Micelle Drug Delivery.

    PubMed

    Xia, Hesheng; Zhao, Yue; Tong, Rui

    2016-01-01

    The synthesis of multi-functional nanocarriers and the design of new stimuli-responsive means are equally important for drug delivery. Ultrasound can be used as a remote, non-invasive and controllable trigger for the stimuli-responsive release of nanocarriers. Polymeric micelles are one kind of potential drug nanocarrier. By combining ultrasound and polymeric micelles, a new modality (i.e., ultrasound-mediated polymeric micelle drug delivery) has been developed and has recently received increasing attention. A major challenge remaining in developing ultrasound-responsive polymeric micelles is the improvement of the sensitivity or responsiveness of polymeric micelles to ultrasound. This chapter reviews the recent advance in this field. In order to understand the interaction mechanism between ultrasound stimulus and polymeric micelles, ultrasound effects, such as thermal effect, cavitation effect, ultrasound sonochemistry (including ultrasonic degradation, ultrasound-initiated polymerization, ultrasonic in-situ polymerization and ultrasound site-specific degradation), as well as basic micellar knowledge are introduced. Ultrasound-mediated polymeric micelle drug delivery has been classified into two main streams based on the different interaction mechanism between ultrasound and polymeric micelles; one is based on the ultrasound-induced physical disruption of the micelle and reversible release of payload. The other is based on micellar ultrasound mechanochemical disruption and irreversible release of payload.

  6. Ultrasonographic percutaneous anatomy of the atlanto-occipital region and indirect ultrasound-guided cisternal puncture in the dog and the cat.

    PubMed

    Etienne, A-L; Audigié, F; Peeters, D; Gabriel, A; Busoni, V

    2015-04-01

    Cisternal puncture in dogs and cats is commonly carried out. This article describes the percutaneous ultrasound anatomy of the cisternal region in the dog and the cat and an indirect technique for ultrasound-guided cisternal puncture. Ultrasound images obtained ex vivo and in vivo were compared with anatomic sections and used to identify the landmarks for ultrasound-guided cisternal puncture. The ultrasound-guided procedure was established in cadavers and then applied in vivo in seven dogs and two cats. The anatomic landmarks for the ultrasound-guided puncture are the cisterna magna, the spinal cord, the two occipital condyles on transverse images, the external occipital crest and the dorsal arch of the first cervical vertebra on longitudinal images. Using these ultrasound anatomic landmarks, an indirect ultrasound-guided technique for cisternal puncture is applicable in the dog and the cat.

  7. Good sensitivity and specificity of ultrasound for detecting pseudotumors in 83 failed metal-on-metal hip replacements

    PubMed Central

    Lainiala, Olli; Elo, Petra; Reito, Aleksi; Pajamäki, Jorma; Puolakka, Timo; Eskelinen, Antti

    2015-01-01

    Background and purpose Ultrasound is used for imaging of pseudotumors associated with metal-on-metal (MoM) hips. Ultrasound has been compared with magnetic resonance imaging, but to date there have been no studies comparing ultrasound findings and revision findings. Methods We evaluated the sensitivity and specificity of preoperative ultrasound for detecting pseudotumors in 82 patients with MoM hip replacement (82 hips). Ultrasound examinations were performed by 1 of 3 musculoskeletal radiologists, and pseudotumors seen by ultrasound were retrospectively classified as fluid-filled, mixed-type, or solid. Findings at revision surgery were retrieved from surgical notes and graded according to the same system as used for ultrasound findings. Results Ultrasound had a sensitivity of 83% (95% CI: 63–93) and a specificity of 92% (CI: 82–96) for detecting trochanteric region pseudotumors, and a sensitivity of 79% (CI: 62–89) and a specificity of 94% (CI: 83–98) for detecting iliopsoas-region pseudotumors. Type misclassification of pseudotumors found at revision occurred in 8 of 23 hips in the trochanteric region and in 19 of 33 hips in the iliopsoas region. Interpretation Despite the discrepancy in type classification between ultrasound and revision findings, the presence of pseudotumors was predicted well with ultrasound in our cohort of failed MoM hip replacements. PMID:25582840

  8. Ultrasound backscatter measurements of intact human proximal femurs--relationships of ultrasound parameters with tissue structure and mineral density.

    PubMed

    Malo, M K H; Töyräs, J; Karjalainen, J P; Isaksson, H; Riekkinen, O; Jurvelin, J S

    2014-07-01

    Ultrasound reflection and backscatter parameters are related to the mechanical and structural properties of bone in vitro. However, the potential of ultrasound reflection and backscatter measurements has not been tested with intact human proximal femurs ex vivo. We hypothesize that ultrasound backscatter can be measured from intact femurs and that the measured backscattered signal is associated with cadaver age, bone mineral density (BMD) and trabecular bone microstructure. In this study, human femoral bones of 16 male cadavers (47.0±16.1 years, range: 21-77 years) were investigated using pulse-echo ultrasound measurements at the femoral neck in the antero-posterior direction and at the trochanter major in the anteroposterior and lateromedial directions. Recently introduced ultrasound backscatter parameters, independent of cortical thickness, e.g., time slope of apparent integrated backscatter (TSAB) and mean of the backscatter difference technique (MBD) were obtained and compared with the structural properties of trabecular bone samples, extracted from the locations of ultrasound measurements. Moreover, more conventional backscatter parameters, e.g., apparent integrated backscatter (AIB) and frequency slope of apparent integrated backscatter (FSAB) were analyzed. Bone mineral density of the intact femurs was evaluated using dual energy X-ray absorptiometry (DXA). AIB and MDB measured from the femoral neck correlated significantly (p<0.01) with the neck BMD (R2=0.44 and 0.45), cadaver age (R2=0.61 and 0.41) and several structural parameters, e.g., bone volume fraction (R2=0.33 and 0.39, p<0.05 and p<0.01), respectively. To conclude, ultrasound backscatter parameters, measured from intact proximal femurs, are significantly related (p<0.05) to structural properties and mineral density of trabecular bone.

  9. Ultrasound versus Clinical Examination to Estimate Fetal Weight at Term

    PubMed Central

    Lanowski, Jan-Simon; Lanowski, Gabriele; Schippert, Cordula; Drinkut, Kristina; Hillemanns, Peter; Staboulidou, Ismini

    2017-01-01

    Introduction At term, fetal weight estimation is an important factor for decisions about the delivery mode and the timing of labor induction. This study aimed to compare the accuracy of abdominal palpation with that of ultrasound performed by different examiners to estimate fetal weight. The study investigated whether differences in the examinersʼ training affected fetal weight estimates. The accuracy of the weight estimates made for fetuses with extreme birth weights was also evaluated. Finally, the accuracy of Johnsonʼs method and of Insler and Bernsteinʼs formula for estimating fetal weight were compared with the other two methods. Methods This prospective study included singleton pregnancies between 37 weeks of gestation and 12 days post-term planned for vaginal delivery or cesarean section. Ultrasound and abdominal palpation using Leopoldʼs maneuvers were performed by examiners with different levels of professional experience. Fetal weight was additionally estimated using Insler and Bernsteinʼs formula and Johnsonʼs method. Statistical analysis calculated the accuracy of fetal weight estimates for the different examiners and the four methods. Results A total of 204 women were included in the analysis. Trained ultrasound examiners were most accurate when estimating fetal weight compared with all other examiners. The comparison of all four methods showed that fetal weight was assessed most accurately with ultrasound. No learning curve could be established. BMI and advanced gestational age affected the accuracy of the estimated weight. The analysis showed that a greater deviation between estimated weight and actual weight occurred with all four methods for fetuses at either end of the extremes of fetal weight, i.e., with very low or very high birth weights. Conclusion Fetal weight should be estimated using ultrasound. A good ultrasound training is essential. PMID:28392581

  10. Ultrasound assisted production of a fibrinolytic enzyme in a bioreactor.

    PubMed

    Avhad, Devchand N; Rathod, Virendra K

    2015-01-01

    The present work illustrates ultrasound assisted production of a fibrinolytic enzyme at 1L bioreactor scale from Bacillus sphaericus MTCC 3672. To alleviate the shortcomings of one factor at a time method of optimization, central composite rotatable design of response surface methodology was employed for optimization of ultrasound assisted production. Different process parameters such as irradiation time, duty cycle and power of ultrasound were varied in 3 different levels in 11 experimental runs. For evaluating mass transfer enhancement effect of ultrasonication on production, control non sonicated fermentation was optimized by varying different agitation speed (300-500rpm) and aeration rate (8.33-33.33cc/s). Optimized ultrasonication protocol resulted in 1.48-fold increase in fibrinolytic enzyme yield as compared to non sonicated fermentation, which comprised of ultrasound irradiation at 25kHz for 10min with 40% duty cycle and 160W power on 12h of growth phase in 1L bioreactor operated at 400rpm agitation speed and 16.66cc/s aeration rate. Declined glucose concentration from 0.1% w/v (non sonicated control run) to 0.05% w/v and breakage of cells cluster emphasized on increased substrate utilization potential and enhanced convection of ultrasound assisted fermentation in a bioreactor. Deliverables of current studies will provide significant insights for enhancement of productivity of various enzymes at a bioreactor level.

  11. Direct visualization of microalgae rupture by ultrasound-driven bubbles

    NASA Astrophysics Data System (ADS)

    Pommella, Angelo; Harun, Irina; Pouliopoulos, Antonis; Choi, James J.; Hellgardt, Klaus; Garbin, Valeria

    2015-11-01

    Cell rupture induced by ultrasound is central to applications in biotechnology. For instance, cell disruption is required in the production of biofuels from microalgae (unicellular species of algae). Ultrasound-induced cavitation, bubble collapse and jetting are exploited to induce sufficiently large viscous stresses to cause rupture of the cell membranes. It has recently been shown that seeding the flow with bubbles that act as cavitation nuclei significantly reduces the energy cost for cell processing. However, a fundamental understanding of the conditions for rupture of microalgae in the complex flow fields generated by ultrasound-driven bubbles is currently lacking. We perform high-speed video microscopy to visualize the miscroscale details of the interaction of Chlamydomonas reinhardtii , microalgae of about 10 μm in size, with ultrasound-driven microbubbles of 2-200 μm in diameter. We investigate the efficiency of cell rupture depending on ultrasound frequency and pressure amplitude (from 10 kPa up to 1 MPa), and the resulting bubble dynamics regimes. In particular we compare the efficiency of membrane rupture in the acoustic microstreaming flow induced by linear oscillations, with the case of violent bubble collapse and jetting. V.G. acknowledges partial support from the European Commission (FP7-PEOPLE-2013-CIG), Grant No. 618333.

  12. [Ultrasound of the thyroid].

    PubMed

    Dietrich, C F; Bojunga, J

    2015-03-01

    Thyroid nodules and thyroid abnormalities are common findings in the general population. Ultrasonography is the most important imaging tool for diagnosing thyroid disease. In the majority of cases a correct diagnosis can already be made in synopsis of the sonographic together with clinical findings and basal thyroid hormone parameters and an appropriate therapy can be initiated thereafter. A differentiation of hormonally active versus inactive nodes, and in particular benign versus malignant nodules is sonographically, however, not reliably possible. In this context, radioscanning has its clinical significance predominantly in diagnosing hormonal activity of thyroid nodules. Efforts of the past years aimed to improve sonographic risk stratification to predict malignancy of thyroid nodules through standardized diagnostic assessment of evaluated risk factors in order to select patients, who need further diagnostic work up. According to the "Breast Imaging Reporting and Data System" (BI-RADS), "Thyroid Imaging Reporting and Data Systems" (TI-RADS) giving standardized categories with rates of malignancy were evaluated as a basis for further clinical management. Recent technological developments, such as elastography, also show promising data and could gain entrance into clinical practice. The ultrasound-guided fine-needle aspiration is the key element in the diagnosis of sonographically suspicious thyroid nodules and significantly contributes to the diagnosis of malignancy versus benignity.

  13. [Ultrasound of the Thyroid].

    PubMed

    Dietrich, C F; Bojunga, J

    2016-02-01

    Thyroid nodules and thyroid abnormalities are common findings in the general population. Ultrasonography is the most important imaging tool for diagnosing thyroid disease. In the majority of cases a correct diagnosis can already be made in synopsis of the sonographic together with clinical findings and basal thyroid hormone parameters and an appropriate therapy can be initiated thereafter. A differentiation of hormonally active vs. inactive nodes, and in particular benign vs. malignant nodules is sonographically, however, not reliably possible. In this context, radioscanning has its clinical significance predominantly in diagnosing hormonal activity of thyroid nodules. Efforts of the past years aimed to improve sonographic risk stratification to predict malignancy of thyroid nodules through standardized diagnostic assessment of evaluated risk factors in order to select patients, who need further diagnostic work up. According to the "Breast Imaging Reporting and Data System" (BI-RADS), "Thyroid Imaging Reporting and Data Systems" (TI-RADS) giving standardized categories with rates of malignancy were evaluated as a basis for further clinical management. Recent technological developments, such as elastography, also showpromising data and could gain entrance into clinical practice. The ultrasound-guided fineneedle aspiration is the key element in the diagnosis of sonographically suspicious thyroid nodules and significantly contributes to the diagnosis of malignancy versus benignity.

  14. Resonant ultrasound spectrometer

    DOEpatents

    Migliori, Albert; Visscher, William M.; Fisk, Zachary

    1990-01-01

    An ultrasound resonant spectrometer determines the resonant frequency spectrum of a rectangular parallelepiped sample of a high dissipation material over an expected resonant response frequency range. A sample holder structure grips corners of the sample between piezoelectric drive and receive transducers. Each transducer is mounted on a membrane for only weakly coupling the transducer to the holder structure and operatively contacts a material effective to remove system resonant responses at the transducer from the expected response range. i.e., either a material such as diamond to move the response frequencies above the range or a damping powder to preclude response within the range. A square-law detector amplifier receives the response signal and retransmits the signal on an isolated shield of connecting cabling to remove cabling capacitive effects. The amplifier also provides a substantially frequency independently voltage divider with the receive transducer. The spectrometer is extremely sensitive to enable low amplitude resonance to be detected for use in calculating the elastic constants of the high dissipation sample.

  15. An improved MRI guided ultrasound system for superficial tumor hyperthermia

    NASA Astrophysics Data System (ADS)

    Zhu, Mengyuan; Shen, Guofeng; Su, Zhiqiang; Chen, Sheng; Wu, Hao

    2017-03-01

    Among many methods in tumor treatment, ultrasound hyperthermia is characterized by non-invasiveness, and it has been proven very effective for clinical treatment. But the problem of monitoring temperature limits its development. MRI-based temperature mapping techniques are safe compared with invasive methods and have been applied to detect temperature changes for a variety of applications. Among these techniques, the proton resonance frequency (PRF) method is relatively advanced. With a temperature measuring experiment and experiment conducted on tumors inside rabbit legs, the effectiveness of PRF method has been proved. This paper is to introduce an MRI guided ultrasound superficial tumor hyperthermia instrument based on PRF method.

  16. [Animal experimental studies on "bone welding" by ultrasound (author's transl)].

    PubMed

    Veihelmann, D; Grözinger, D

    1981-12-01

    This article deals with a method of osteosynthesis which was tried out in a model experiment on Wistar rats. In this method, which may be termed "bone welding with ultrasound", bone fragments are glued together, using ultrasound and n-butyl-2-cyanoacrylates. The load capacities of glued and welded bones were compared in an in-vitro trial. The course of the in-vivo trial was followed up clinically and roentgenologically, and the preparations obtained after termination of an observation period of 6 weeks were then subjected to histological processing.

  17. Growth factor and ultrasound-assisted bioreactor synergism for human mesenchymal stem cell chondrogenesis

    PubMed Central

    Thakurta, Sanjukta Guha; Budhiraja, Gaurav

    2015-01-01

    Ultrasound at 5.0 MHz was noted to be chondro-inductive, with improved SOX-9 gene and COL2A1 protein expression in constructs that allowed for cell-to-cell contact. To achieve tissue-engineered cartilage using macroporous scaffolds, it is hypothesized that a combination of ultrasound at 5.0 MHz and transforming growth factor-β3 induces human mesenchymal stem cell differentiation to chondrocytes. Expression of miR-145 was used as a metric to qualitatively assess the efficacy of human mesenchymal stem cell conversion. Our results suggest that in group 1 (no transforming growth factor-β3, no ultrasound), as anticipated, human mesenchymal stem cells were not efficiently differentiated into chondrocytes, judging by the lack of decrease in the level of miR-145 expression. Human mesenchymal stem cells differentiated into chondrocytes in group 2 (transforming growth factor-β3, no ultrasound) and group 3 (transforming growth factor-β3, ultrasound) with group 3 having a 2-fold lower miR-145 when compared to group 2 at day 7, indicating a higher conversion to chondrocytes. Transforming growth factor-β3–induced chondrogenesis with and without ultrasound stimulation for 14 days in the ultrasound-assisted bioreactor was compared and followed by additional culture in the absence of growth factors. The combination of growth factor and ultrasound stimulation (group 3) resulted in enhanced COL2A1, SOX-9, and ACAN protein expression when compared to growth factor alone (group 2). No COL10A1 protein expression was noted. Enhanced cell proliferation and glycosaminoglycan deposition was noted with the combination of growth factor and ultrasound stimulation. These results suggest that ultrasound at 5.0 MHz could be used to induce chondrogenic differentiation of mesenchymal stem cells for cartilage tissue engineering. PMID:25610590

  18. Tissue harmonic synthetic aperture ultrasound imaging.

    PubMed

    Hemmsen, Martin Christian; Rasmussen, Joachim Hee; Jensen, Jørgen Arendt

    2014-10-01

    Synthetic aperture sequential beamforming (SASB) and tissue harmonic imaging (THI) are combined to improve the image quality of medical ultrasound imaging. The technique is evaluated in a comparative study against dynamic receive focusing (DRF). The objective is to investigate if SASB combined with THI improves the image quality compared to DRF-THI. The major benefit of SASB is a reduced bandwidth between the probe and processing unit. A BK Medical 2202 Ultraview ultrasound scanner was used to acquire beamformed RF data for offline evaluation. The acquisition was made interleaved between methods, and data were recorded with and without pulse inversion for tissue harmonic imaging. Data were acquired using a Sound Technology 192 element convex array transducer from both a wire phantom and a tissue mimicking phantom to investigate spatial resolution and penetration. In vivo scans were also performed for a visual comparison. The spatial resolution for SASB-THI is on average 19% better than DRI-THI, and the investigation of penetration showed equally good signal-to-noise ratio. In vivo B-mode scans were made and compared. The comparison showed that SASB-THI reduces the artifact and noise interference and improves image contrast and spatial resolution.

  19. Ultrasound-Induced New Cellular Mechanism Involved in Drug Resistance

    PubMed Central

    Hassan, Mariame A.; Furusawa, Yukihiro; Minemura, Masami; Rapoport, Natalya; Sugiyama, Toshiro; Kondo, Takashi

    2012-01-01

    The acoustic effects in a biological milieu offer several scenarios for the reversal of multidrug resistance. In this study, we have observed higher sensitivity of doxorubicin-resistant uterine sarcoma MES-SA/DX5 cells to ultrasound exposure compared to its parent counterpart MES-SA cells; however, the results showed that the acoustic irradiation was genotoxic and could promote neotic division in exposed cells that was more pronounced in the resistant variant. The neotic progeny, imaged microscopically 24 hr post sonication, could contribute in modulating the final cell survival when an apoptotic dose of doxorubicin was combined with ultrasound applied either simultaneously or sequentially in dual-treatment protocols. Depending on the time and order of application of ultrasound and doxorubicin in combination treatments, there was either desensitization of the parent cells or sensitization of the resistant cells to doxorubicin action. PMID:23284614

  20. Ultrasound assisted biogas production from landfill leachate.

    PubMed

    Oz, Nilgün Ayman; Yarimtepe, Canan Can

    2014-07-01

    The aim of this study is to increase biogas production and methane yield from landfill leachate in anaerobic batch reactors by using low frequency ultrasound as a pretreatment step. In the first part of the study, optimum conditions for solubilization of organic matter in leachate samples were investigated using various sonication durations at an ultrasound frequency of 20 kHz. The level of organic matter solubilization during ultrasonic pretreatment experiments was determined by calculating the ratio of soluble chemical oxygen demand (sCOD) to total chemical oxygen demand (tCOD). The sCOD/tCOD ratio was increased from 47% in raw leachate to 63% after 45 min sonication at 600 W/l. Non-parametric Friedman's test indicated that ultrasonic pretreatment has a significant effect on sCOD parameter for leachate (p<0.05). In the second part of the study, anaerobic batch reactors were operated for both ultrasonically pretreated and untreated landfill leachate samples in order to assess the effect of sonication on biogas and methane production rate. In anaerobic batch reactor feed with ultrasonically pretreated leachate, 40% more biogas was obtained compared to the control reactor. For statistical analysis, Mann-Whitney U test was performed to compare biogas and methane production rates for raw and pretreated leachate samples and it has been found that ultrasonic pretreatment significantly enhanced biogas and methane production rates from leachate (p<0.05) in anaerobic batch reactors. The overall results showed that low frequency ultrasound pretreatment can be potentially used for wastewater management especially with integration of anaerobic processes.

  1. Ultrasound-Guided Needle Technique Accuracy

    PubMed Central

    Johnson, Angela N.; Peiffer, Jeffery S.; Halmann, Nahi; Delaney, Luke; Owen, Cindy A.; Hersh, Jeff

    2017-01-01

    Background and Objectives Ultrasound-guided regional anesthesia facilitates an approach to sensitive targets such as nerve clusters without contact or inadvertent puncture. We compared accuracy of needle placement with a novel passive magnetic ultrasound needle guidance technology (NGT) versus conventional ultrasound (CU) with echogenic needles. Methods Sixteen anesthesiologists and 19 residents performed a series of 16 needle insertion tasks each, 8 using NGT (n = 280) and 8 using CU (n = 280), in high-fidelity porcine phantoms. Tasks were stratified based on aiming to contact (target-contact) or place in close proximity with (target-proximity) targets, needle gauge (no. 18/no. 22), and in-plane (IP) or out-of-plane (OOP) approach. Distance to the target, task completion by aim, number of passes, and number of tasks completed on the first pass were reported. Results Needle guidance technology significantly improved distance, task completion, number of passes, and completion on the first pass compared with CU for both IP and OOP approaches (P ≤ 0.001). Average NGT distance to target was lower by 57.1% overall (n = 560, 1.5 ± 2.4 vs 3.5 ± 3.7 mm), 38.5% IP (n = 140, 1.6 ± 2.6 vs 2.6 ± 2.8 mm), and 68.2% OOP (n = 140, 1.4 ± 2.2 vs 4.4 ± 4.3 mm) (all P ≤ 0.01). Subgroup analyses revealed accuracy gains were largest among target-proximity tasks performed by residents and for OOP approaches. Needle guidance technology improved first-pass completion from 214 (76.4%) per 280 to 249 (88.9%) per 280, a significant improvement of 16.4% (P = 0.001). Conclusions Passive magnetic NGT can improve accuracy of needle procedures, particularly among OOP procedures requiring close approach to sensitive targets, such as nerve blocks in anesthesiology practice. PMID:28079754

  2. Antibacterial effect of zinc oxide nanoparticles combined with ultrasound

    NASA Astrophysics Data System (ADS)

    Seil, Justin T.; Webster, Thomas J.

    2012-12-01

    Using Staphylococcus aureus (S. aureus), the present study investigated the antibacterial effect of ZnO nanoparticles both in the absence and presence of ultrasound stimulation. While the antibacterial effect of control nanoparticle chemistries (Al2O3) alone was either weak or unobservable under the conditions tested, the antibacterial effect of ZnO alone was significant, providing over a four log reduction (equivalent to antibiotics) compared to no treatment after just 8 h. The antibacterial effect was enhanced as ZnO particle diameter decreased. Specifically, when testing the antibacterial effect against bacteria populations relevant to infection, a 500 μg ml-1 dose of zinc oxide nanoparticles with a diameter of 20 nm reduced S. aureus populations by four orders of magnitude after 8 and 24 h, compared to control groups with no nanoparticles. This was accomplished without the use of antibiotics, to which bacteria are developing a resistance anyway. The addition of ultrasound stimulation further reduced the number of viable colony-forming units present in a planktonic cell suspension by 76% compared to nanoparticles alone. Lastly, this study provided a mechanism for how ZnO nanoparticles in the presence of ultrasound decrease bacteria functions by demonstrating greater hydrogen peroxide generation by S. aureus compared to controls. These results indicated that small-diameter ZnO nanoparticles exhibited strong antibacterial properties that can be additionally enhanced in the presence of ultrasound and, thus, should be further studied for a wide range of medical device anti-infection applications.

  3. Antibacterial effect of zinc oxide nanoparticles combined with ultrasound.

    PubMed

    Seil, Justin T; Webster, Thomas J

    2012-12-14

    Using Staphylococcus aureus (S. aureus), the present study investigated the antibacterial effect of ZnO nanoparticles both in the absence and presence of ultrasound stimulation. While the antibacterial effect of control nanoparticle chemistries (Al(2)O(3)) alone was either weak or unobservable under the conditions tested, the antibacterial effect of ZnO alone was significant, providing over a four log reduction (equivalent to antibiotics) compared to no treatment after just 8 h. The antibacterial effect was enhanced as ZnO particle diameter decreased. Specifically, when testing the antibacterial effect against bacteria populations relevant to infection, a 500 μg ml(-1) dose of zinc oxide nanoparticles with a diameter of 20 nm reduced S. aureus populations by four orders of magnitude after 8 and 24 h, compared to control groups with no nanoparticles. This was accomplished without the use of antibiotics, to which bacteria are developing a resistance anyway. The addition of ultrasound stimulation further reduced the number of viable colony-forming units present in a planktonic cell suspension by 76% compared to nanoparticles alone. Lastly, this study provided a mechanism for how ZnO nanoparticles in the presence of ultrasound decrease bacteria functions by demonstrating greater hydrogen peroxide generation by S. aureus compared to controls. These results indicated that small-diameter ZnO nanoparticles exhibited strong antibacterial properties that can be additionally enhanced in the presence of ultrasound and, thus, should be further studied for a wide range of medical device anti-infection applications.

  4. Antenatal Ultrasound and Risk of Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Grether, Judith K.; Li, Sherian Xu; Yoshida, Cathleen K.; Croen, Lisa A.

    2010-01-01

    We evaluated antenatal ultrasound (U/S) exposure as a risk factor for autism spectrum disorders (ASD), comparing affected singleton children and control children born 1995-1999 and enrolled in the Kaiser Permanente health care system. Among children with ASD (n = 362) and controls (n = 393), 13% had no antenatal exposure to U/S examinations;…

  5. Influence of mixing and ultrasound frequency on antisolvent crystallisation of sodium chloride.

    PubMed

    Lee, Judy; Ashokkumar, Muthupandian; Kentish, Sandra E

    2014-01-01

    Ultrasound is known to promote nucleation of crystals and produce a narrower size distribution in a controlled and reproducible manner for the crystallisation process. Although there are various theories that suggest cavitation bubbles are responsible for sonocrystallisation, most studies use power ultrasonic horns that generate both intense shear and cavitation and this can mask the role that cavitation bubbles play. High frequency ultrasound from a plate transducer can be used to examine the effect of cavitation bubbles without the intense shear effect. This study reports the crystal size and morphology with various mixing speeds and ultrasound frequencies. The results show high frequency ultrasound produced sodium chloride crystals of similar size distribution as an ultrasonic horn. In addition, ultrasound generated sodium chloride crystals having a more symmetrical cubic structure compared to crystals produced by a high shear mixer.

  6. Feasibility of ultrasound imaging of osteochondral defects in the ankle: a clinical pilot study.

    PubMed

    Kok, A C; Terra, M P; Muller, S; Askeland, C; van Dijk, C N; Kerkhoffs, G M M J; Tuijthof, G J M

    2014-10-01

    Talar osteochondral defects (OCDs) are imaged using magnetic resonance imaging (MRI) or computed tomography (CT). For extensive follow-up, ultrasound might be a fast, non-invasive alternative that images both bone and cartilage. In this study the potential of ultrasound, as compared with CT, in the imaging and grading of OCDs is explored. On the basis of prior CT scans, nine ankles of patients without OCDs and nine ankles of patients with anterocentral OCDs were selected and classified using the Loomer CT classification. A blinded expert skeletal radiologist imaged all ankles with ultrasound and recorded the presence of OCDs. Similarly to CT, ultrasound revealed typical morphologic OCD features, for example, cortex irregularities and loose fragments. Cartilage disruptions, Loomer grades IV (displaced fragment) and V (cyst with fibrous roof), were visible as well. This study encourages further research on the use of ultrasound as a follow-up imaging modality for OCDs located anteriorly or centrally on the talar dome.

  7. Role of Guided Ultrasound in the Treatment of De Quervain Tenosynovitis by Local Steroid Infiltration.

    PubMed

    Danda, Raja Shekar; Kamath, Jagannath; Jayasheelan, Nikil; Kumar, Prashanth

    2016-04-01

    Ultrasound guidance for steroid injection in de Quervain disease is useful in identifying the presence of subcompartments and effectively injecting the drug into tendon sheath. We prospectively studied 50 patients with features of de Quervain disease to determine the effectiveness of ultrasound in positioning of needle for steroid injection and effectiveness of single versus multiple injections in the presence of subcompartments. Scalp vein set was inserted into the tendon sheath under ultrasound guidance and sterile conditions. Mixture containing 1 mL of methylprednisolone 40 mg with 1 mL of 2% lignocaine was injected and the patient followed for 6 months. In patients having subcompartments, improvement was better when two separate injections into each subcompartment were given compared with single. Ultrasound guidance is helpful in identifying the existence of subcompartment and injecting the subcompartments separately. Scalp vein set may be very effective in ultrasound-guided injection. This is a level III study.

  8. Performance characteristics of ultrasound of the knee in a general radiological setting.

    PubMed

    Bruce, Warwick; Lee, Tack Shin; Sundarajan, Vijaya; Walker, Peter; Magnussen, John; Van der Wall, Hans

    2004-08-01

    Ultrasound of the musculoskeletal system is an attractive imaging modality due to the lack of ionising radiation, cost and ease of availability. A role has been established in the shoulder and pediatric hip but not in the knee. Ultrasound studies of the knee performed at six general radiological practices without established musculoskeletal expertise were compared with clinical examination in 56 patients. Final diagnoses were established by arthroscopy and/or MRI. The sensitivity and specificity for detection of superficial lesions in the knee were 88 and 41% for clinical examination and 32 and 59% for ultrasound. For deep lesions sensitivity and specificity were 61 and 64% for clinical examination and 13 and 100% for ultrasound. Ultrasound studies of the knee in a general radiological practice do not offer significant information above clinical examination.

  9. Characterization of vascular strain during in-vitro angioplasty with high-resolution ultrasound speckle tracking

    PubMed Central

    2010-01-01

    Background Ultrasound elasticity imaging provides biomechanical and elastic properties of vascular tissue, with the potential to distinguish between tissue motion and tissue strain. To validate the ability of ultrasound elasticity imaging to predict structurally defined physical changes in tissue, strain measurement patterns during angioplasty in four bovine carotid artery pathology samples were compared to the measured physical characteristics of the tissue specimens. Methods Using computational image-processing techniques, the circumferences of each bovine artery specimen were obtained from ultrasound and pathologic data. Results Ultrasound-strain-based and pathology-based arterial circumference measurements were correlated with an R2 value of 0.94 (p = 0.03). The experimental elasticity imaging results confirmed the onset of deformation of an angioplasty procedure by indicating a consistent inflection point where vessel fibers were fully unfolded and vessel wall strain initiated. Conclusion These results validate the ability of ultrasound elasticity imaging to measure localized mechanical changes in vascular tissue. PMID:20727172

  10. Diffraction and coherence in breast ultrasound tomography: a study with a toroidal array

    SciTech Connect

    Huang, Lianjie; Simonetti, Francesco; Duric, Neb; Littrup, Peter

    2008-01-01

    Ultrasound is commonly used as an adjunct to mammography for diagnostic evaluation of suspicions arising from breast cancer screening. As an alternative to conventional sonography that uses hand-held transducers, toroidal array probes that encircle the breast immersed in a water bath have been investigated for ultrasound tomography. In this paper, two sets of experiments performed with a prototype ultrasound scanner on a phantom and a human breast in vivo are used to investigate the effects of diffraction and coherence in ultrasound tomography. Reconstructions obtained with transmission diffraction tomography (TDT) are compared with conventional reflection imaging and computerized ultrasound tomography showing a substantial improvement. The in vivo tests demonstrate that TDT can image the complex boundary of a cancer mass and suggest that it can reveal the anatomy of milk ducts and Cooper's ligaments.

  11. Tumor specific ultrasound enhanced gene transfer in vivo with novel liposomal bubbles.

    PubMed

    Suzuki, Ryo; Takizawa, Tomoko; Negishi, Yoichi; Utoguchi, Naoki; Sawamura, Kaori; Tanaka, Kumiko; Namai, Eisuke; Oda, Yusuke; Matsumura, Yasuhiro; Maruyama, Kazuo

    2008-01-22

    Bubble liposomes (liposomes which entrap an ultrasound imaging gas) may constitute a unique system for delivering various molecules efficiently into mammalian cells in vitro. In this study, Bubble liposomes were compared with cationic lipid (CL)-DNA complexes as potential gene delivery carriers into tumor in vivo. The delivery of genes by Bubble liposomes depended on the intensity of the applied ultrasound. Transfection efficiency plateaued at 0.7 W/cm(2) ultrasound intensity. Bubble liposomes efficiently transferred genes into cultured cells even when the cells were exposed to ultrasound for only 1 s. In addition, Bubble liposomes could introduce the luciferase gene more effectively than CL-DNA complexes into mouse ascites tumor cells and solid tumor tissue. We conclude that the combination of Bubble liposomes and ultrasound is a minimally-invasive and tumor specific gene transfer method in vivo.

  12. A deconvolution method for deriving the transit time spectrum for ultrasound propagation through cancellous bone replica models.

    PubMed

    Langton, Christian M; Wille, Marie-Luise; Flegg, Mark B

    2014-04-01

    The acceptance of broadband ultrasound attenuation for the assessment of osteoporosis suffers from a limited understanding of ultrasound wave propagation through cancellous bone. It has recently been proposed that the ultrasound wave propagation can be described by a concept of parallel sonic rays. This concept approximates the detected transmission signal to be the superposition of all sonic rays that travel directly from transmitting to receiving transducer. The transit time of each ray is defined by the proportion of bone and marrow propagated. An ultrasound transit time spectrum describes the proportion of sonic rays having a particular transit time, effectively describing lateral inhomogeneity of transit times over the surface of the receiving ultrasound transducer. The aim of this study was to provide a proof of concept that a transit time spectrum may be derived from digital deconvolution of input and output ultrasound signals. We have applied the active-set method deconvolution algorithm to determine the ultrasound transit time spectra in the three orthogonal directions of four cancellous bone replica samples and have compared experimental data with the prediction from the computer simulation. The agreement between experimental and predicted ultrasound transit time spectrum analyses derived from Bland-Altman analysis ranged from 92% to 99%, thereby supporting the concept of parallel sonic rays for ultrasound propagation in cancellous bone. In addition to further validation of the parallel sonic ray concept, this technique offers the opportunity to consider quantitative characterisation of the material and structural properties of cancellous bone, not previously available utilising ultrasound.

  13. Contrast-enhanced ultrasound in ovarian tumors – diagnostic parameters: method presentation and initial experience

    PubMed Central

    MAXIM, ANITA-ROXANA; BADEA, RADU; TAMAS, ATILLA; TRAILA, ALEXANDRU

    2013-01-01

    The aim of this paper is to discuss and illustrate the use of contrast-enhanced ultrasound in evaluating ovarian tumors compared to conventional ultrasound, Doppler ultrasound and the histopathological analysis and suggest how this technique may best be used to distinguish benign from malignant ovarian masses. We present the method and initial experience of our center by analyzing the parameters used in contrast-enhanced ultrasound in 6 patients with ovarian tumors of uncertain etiology. For examination we used a Siemens ultrasound machine with dedicated contrast software and the contrast agent SonoVue, Bracco. The patients underwent conventional ultrasound, Doppler ultrasound and i.v. administration of the contrast agent. The parameters studied were: inflow of contrast (rise time), time to peak enhancement, mean transit time. The series of patients is part of an extensive prospective PhD study aimed at elaborating a differential diagnosis protocol for benign versus malignant ovarian tumors, by validating specific parameters for contrast-enhanced ultrasound. Although the method is currently used with great success in gastroenterology, urology and senology, its validation in gynecology is still in the early phases. Taking into consideration that the method is minimally invasive and much less costly that CT/MRI imaging, demonstrating its utility in oncologic gynecology would be a big step in preoperative evaluation of these cases. PMID:26527912

  14. Projection-reflection ultrasound images using PE-CMOS sensor: a preliminary bone fracture study

    NASA Astrophysics Data System (ADS)

    Lo, Shih-Chung B.; Liu, Chu-Chuan; Freedman, Matthew T.; Mun, Seong-Ki; Kula, John; Lasser, Marvin E.; Lasser, Bob; Wang, Yue Joseph

    2008-03-01

    In this study, we investigated the characteristics of the ultrasound reflective image obtained by a CMOS sensor array coated with piezoelectric material (PE-CMOS). The laboratory projection-reflection ultrasound prototype consists of five major components: an unfocused ultrasound transducer, an acoustic beam splitter, an acoustic compound lens, a PE-CMOS ultrasound sensing array (Model I400, Imperium Inc. Silver Spring, MD), and a readout circuit system. The prototype can image strong reflective materials such as bone and metal. We found this projection-reflection ultrasound prototype is able to reveal hairline bone fractures with and without intact skin and tissue. When compared, the image generated from a conventional B-scan ultrasound on the same bone fracture is less observable. When it is observable with the B-scan system, the fracture or crack on the surface only show one single spot of echo due to its scan geometry. The corresponding image produced from the projection-reflection ultrasound system shows a bright blooming strip on the image clearly indicating the fracture on the surface of the solid material. Speckles of the bone structure are also observed in the new ultrasound prototype. A theoretical analysis is provided to link the signals as well as speckles detected in both systems.

  15. Effect of ultrasound on cyprid footprint and juvenile barnacle adhesion on a fouling release material.

    PubMed

    Guo, Shifeng; Khoo, Boo Cheong; Teo, Serena Lay Ming; Zhong, Shaoping; Lim, Chwee Teck; Lee, Heow Pueh

    2014-03-01

    In our earlier studies, we have demonstrated that low and high intensity ultrasound can prevent barnacle cyprid settlement. In this study, we found that ultrasound treatment reduced the adhesion of newly metamorphosed barnacles up to 2 days' old. This was observed in the reduction of adhesion strength of the newly settled barnacles from ultrasound treated cyprids on silicone substrate compared to the adhesion strength of barnacles metamorphosed from cyprids not exposed to ultrasound. Atomic force microscopy (AFM) was used to analyze the effect of ultrasound on barnacle cyprid footprints (FPs), which are protein adhesives secreted when the larvae explore surfaces. The ultrasound treated cyprids were found to secrete less FPs, which appeared to spread a larger area than those generated by untreated cyprids. The evidence from this study suggests that ultrasound treatment results in a reduced cyprid settlement and footprint secretion, and may affect the subsequent recruitment of barnacles onto fouling release surfaces by reducing the ability of early settlement stage of barnacles (up to 2 days' old) from firmly adhering to the substrates. Ultrasound therefore can be used in combination with fouling release coatings to offer a more efficient antifouling strategy.

  16. Low-Power 2-MHz Pulsed-Wave Transcranial Ultrasound Reduces Ischemic Brain Damage in Rats.

    PubMed

    Alexandrov, Andrei V; Barlinn, Kristian; Strong, Roger; Alexandrov, Anne W; Aronowski, Jaroslaw

    2011-09-01

    It is largely unknown whether prolonged insonation with ultrasound impacts the ischemic brain tissue by itself. Our goal was to evaluate safety and the effect of high-frequency ultrasound on infarct volume in rats. Thirty-two Long-Evans rats with permanent middle cerebral and carotid artery occlusions received either 2-MHz ultrasound at two levels of insonation power (128 or 10 mW) or no ultrasound (controls). We measured cerebral hemorrhage, indirect and direct infarct volume as well as edema volume at 24 h. No cerebral hemorrhages were detected in all animals. Exposure to low-power (10 mW) ultrasound resulted in a significantly decreased indirect infarct volume (p = 0.0039), direct infarct volume (p = 0.0031), and brain edema volume (p = 0.01) compared with controls. High-power (128 mW) ultrasound had no significant effects. An additional experiment with India ink showed a greater intravascular penetration of dye into ischemic tissues exposed to low-power ultrasound. Insonation with high-frequency, low-power ultrasound reduces ischemic brain damage in rat. Its effect on edema reduction and possible promotion of microcirculation could be used to facilitate drug and nutrient delivery to ischemic areas.

  17. Investigation into the potential of low-frequency ultrasound facilitated topical delivery of Cyclosporin A.

    PubMed

    Liu, Hongzhuo; Li, Sanming; Pan, Weisan; Wang, Yongjun; Han, Fei; Yao, Huimin

    2006-12-01

    The potential for low-frequency ultrasound facilitated topical transport of Cyclosporin A was investigated using rat skin. Studies of intensity and exposure time acting on the deposition of Cyclosporin A into deeper skin of in vitro sonophoresis were performed. Low-frequency ultrasound increased the amount of Cyclosporin A retained in the skin only seven times than the passive diffusion. Furthermore, we also tested the synergistic effect of ultrasound and other approaches such as chemical enhancers and electroporation on topical drug delivery of Cyclosporin A. We found that the efficacy of low-frequency ultrasound in enhancing topical delivery could be further increased by pretreatment of skin with chemical enhancers, such as laurocapram (Azone) and sodium lauryl sulfate (SLS). Meanwhile only a small amount was seen to across the full skin into the receiver compartment. Trimodality treatment comprising of pretreatment with Azone+ultrasound in combination followed by electroporation was not effective in enhancing the topical delivery of Cyclosporin A. However, this combination strategy increased the penetration of Cyclosporin A through rat skin by order of 15. The histopathological findings revealed that there was almost no change observed in the structure of skin after ultrasound or combination with ultrasound and enhancers as compared with the control group. In general, the enhanced skin accumulation of Cyclosporin A by the combination of low-frequency ultrasound and chemical enhancers could help significantly to optimize the targeting of the drug without of a concomitant increase of the systemic side effects.

  18. Heel Ultrasound Scan in Detecting Osteoporosis in Low Trauma Fracture Patients.

    PubMed

    Hashmi, Faiz R; Elfandi, Khaled O

    2016-06-27

    Osteoporosis is the most common metabolic disease with significant impact on the morbidity and mortality of affected patients. Osteoporosis has a significant impact on the economy worldwide. The aim of this study was to find out whether heel ultrasound is as good as central bone densitometry scanning in diagnosing osteoporosis in patients who are at high risk of osteoporosis. This was a prospective study of patients comparing heel ultrasound to central bone densitometry scanning (dual X-ray absorptiometry, DEXA) in patients. The recruited patients attended for a DEXA scan of the left hip and lumbar spine. All subjects had an ultrasound of the left heel using the quantitative heel ultrasound machine. The results of DEXA scan were blinded from the results of ultrasound and vice versa. There were 59 patients who took part in the study, 12 men and 47 women. The mean age was 66 years (SD 11.9) and mean weight was 62.5 kg (SD 10.7). The sensitivity and specificity of the ultrasound heel test to predict osteoporosis were 53% (95%CI: 29-77) and 86% (95%CI: 75-96) respectively. Specificity for predicting bone mineral density (BMD)-defined osteoporosis was high (86%), but sensitivity was low (53%). A heel ultrasound result in the osteoporotic range was highly predictive of BMD-defined osteoporosis. A positive ultrasound heel test in high risk patients is more useful in ruling in osteoporosis than a negative test to rule out osteoporosis.

  19. Noninvasive measurement of acoustic field inside mother's uterus generated by ultrasound scanning

    NASA Astrophysics Data System (ADS)

    Antonets, V. A.; Kazakov, V. V.

    2015-07-01

    Sounds in the audible range arising in mother's uterus during conventional ultrasound scanning were recorded noninvasively for the first time. It was found that their level is comparable with the level of spoken language.

  20. Comparison of ultrasound-assisted cloud point extraction and ultrasound-assisted dispersive liquid liquid microextraction for copper coupled with spectrophotometric determination

    NASA Astrophysics Data System (ADS)

    Yang, Shengchun; Fang, Xiang; Duan, Liju; Yang, Shu; Lei, Zirong; Wen, Xiaodong

    2015-09-01

    In this work, ultrasound-assisted cloud point extraction (UA-CPE) and ultrasound-assisted dispersive liquid liquid microextraction (UA-DLLME) were investigated and compared firstly as ultrasound-assisted liquid phase microextraction methods, which were coupled with spectrophotometer for copper preconcentration and detection. Compared to conventional CPE and DLLME, the extraction patterns were changed and improved by the effect of ultrasound. As novel methods, their applications were expanded and the analytical performance of spectrophotometric determination for copper was considerably improved. The influence factors of UA-CPE and UA-DLLME were studied in detail. Under the optimal conditions, the limits of detection (LODs) for copper were 0.7 μg L-1 of UA-CPE and 0.8 μg L-1 of UA-DLLME with sensitivity enhancement factors (EFs) of 17 and 16. The developed methods were applied to the determination of trace copper in real water samples with satisfactory analytical results.

  1. Comparison of ultrasound-assisted cloud point extraction and ultrasound-assisted dispersive liquid liquid microextraction for copper coupled with spectrophotometric determination.

    PubMed

    Yang, Shengchun; Fang, Xiang; Duan, Liju; Yang, Shu; Lei, Zirong; Wen, Xiaodong

    2015-09-05

    In this work, ultrasound-assisted cloud point extraction (UA-CPE) and ultrasound-assisted dispersive liquid liquid microextraction (UA-DLLME) were investigated and compared firstly as ultrasound-assisted liquid phase microextraction methods, which were coupled with spectrophotometer for copper preconcentration and detection. Compared to conventional CPE and DLLME, the extraction patterns were changed and improved by the effect of ultrasound. As novel methods, their applications were expanded and the analytical performance of spectrophotometric determination for copper was considerably improved. The influence factors of UA-CPE and UA-DLLME were studied in detail. Under the optimal conditions, the limits of detection (LODs) for copper were 0.7 μg L(-1) of UA-CPE and 0.8 μg L(-1) of UA-DLLME with sensitivity enhancement factors (EFs) of 17 and 16. The developed methods were applied to the determination of trace copper in real water samples with satisfactory analytical results.

  2. Design of a Thermoacoustic Sensor for Low Intensity Ultrasound Measurements Based on an Artificial Neural Network.

    PubMed

    Xing, Jida; Chen, Jie

    2015-06-23

    In therapeutic ultrasound applications, accurate ultrasound output intensities are crucial because the physiological effects of therapeutic ultrasound are very sensitive to the intensity and duration of these applications. Although radiation force balance is a benchmark technique for measuring ultrasound intensity and power, it is costly, difficult to operate, and compromised by noise vibration. To overcome these limitations, the development of a low-cost, easy to operate, and vibration-resistant alternative device is necessary for rapid ultrasound intensity measurement. Therefore, we proposed and validated a novel two-layer thermoacoustic sensor using an artificial neural network technique to accurately measure low ultrasound intensities between 30 and 120 mW/cm2. The first layer of the sensor design is a cylindrical absorber made of plexiglass, followed by a second layer composed of polyurethane rubber with a high attenuation coefficient to absorb extra ultrasound energy. The sensor determined ultrasound intensities according to a temperature elevation induced by heat converted from incident acoustic energy. Compared with our previous one-layer sensor design, the new two-layer sensor enhanced the ultrasound absorption efficiency to provide more rapid and reliable measurements. Using a three-dimensional model in the K-wave toolbox, our simulation of the ultrasound propagation process demonstrated that the two-layer design is more efficient than the single layer design. We also integrated an artificial neural network algorithm to compensate for the large measurement offset. After obtaining multiple parameters of the sensor characteristics through calibration, the artificial neural network is built to correct temperature drifts and increase the reliability of our thermoacoustic measurements through iterative training about ten seconds. The performance of the artificial neural network method was validated through a series of experiments. Compared to our previous

  3. Design of a Thermoacoustic Sensor for Low Intensity Ultrasound Measurements Based on an Artificial Neural Network

    PubMed Central

    Xing, Jida; Chen, Jie

    2015-01-01

    In therapeutic ultrasound applications, accurate ultrasound output intensities are crucial because the physiological effects of therapeutic ultrasound are very sensitive to the intensity and duration of these applications. Although radiation force balance is a benchmark technique for measuring ultrasound intensity and power, it is costly, difficult to operate, and compromised by noise vibration. To overcome these limitations, the development of a low-cost, easy to operate, and vibration-resistant alternative device is necessary for rapid ultrasound intensity measurement. Therefore, we proposed and validated a novel two-layer thermoacoustic sensor using an artificial neural network technique to accurately measure low ultrasound intensities between 30 and 120 mW/cm2. The first layer of the sensor design is a cylindrical absorber made of plexiglass, followed by a second layer composed of polyurethane rubber with a high attenuation coefficient to absorb extra ultrasound energy. The sensor determined ultrasound intensities according to a temperature elevation induced by heat converted from incident acoustic energy. Compared with our previous one-layer sensor design, the new two-layer sensor enhanced the ultrasound absorption efficiency to provide more rapid and reliable measurements. Using a three-dimensional model in the K-wave toolbox, our simulation of the ultrasound propagation process demonstrated that the two-layer design is more efficient than the single layer design. We also integrated an artificial neural network algorithm to compensate for the large measurement offset. After obtaining multiple parameters of the sensor characteristics through calibration, the artificial neural network is built to correct temperature drifts and increase the reliability of our thermoacoustic measurements through iterative training about ten seconds. The performance of the artificial neural network method was validated through a series of experiments. Compared to our previous

  4. Ultrasound Imaging Velocimetry: a review

    NASA Astrophysics Data System (ADS)

    Poelma, Christian

    2017-01-01

    Whole-field velocity measurement techniques based on ultrasound imaging (a.k.a. `ultrasound imaging velocimetry' or `echo-PIV') have received significant attention from the fluid mechanics community in the last decade, in particular because of their ability to obtain velocity fields in flows that elude characterisation by conventional optical methods. In this review, an overview is given of the history, typical components and challenges of these techniques. The basic principles of ultrasound image formation are summarised, as well as various techniques to estimate flow velocities; the emphasis is on correlation-based techniques. Examples are given for a wide range of applications, including in vivo cardiovascular flow measurements, the characterisation of sediment transport and the characterisation of complex non-Newtonian fluids. To conclude, future opportunities are identified. These encompass not just optimisation of the accuracy and dynamic range, but also extension to other application areas.

  5. Ultrasound: from Earth to space.

    PubMed

    Law, Jennifer; Macbeth, Paul B

    2011-06-01

    Ultrasonography is a versatile imaging modality that offers many advantages over radiography, computed tomography, and magnetic resonance imaging. On Earth, the use of ultrasound has become standard in many areas of medicine including diagnosis of medical and surgical diseases, management of obstetric and gynecologic conditions, assessment of critically ill patients, and procedural guidance. Advances in telecommunications have enabled remotely-guided ultrasonography for both geographically isolated populations and astronauts aboard the International Space Station. While ultrasound has traditionally been used in spaceflight to study anatomical and physiological adaptations to microgravity and evaluate countermeasures, recent years have seen a growth of applications adapted from terrestrial techniques. Terrestrial, remote, and space applications for ultrasound are reviewed in this paper.

  6. Neuromuscular Ultrasound of Cranial Nerves

    PubMed Central

    Tawfik, Eman A.; Cartwright, Michael S.

    2015-01-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed. PMID:25851889

  7. Power ultrasound in meat processing.

    PubMed

    Alarcon-Rojo, A D; Janacua, H; Rodriguez, J C; Paniwnyk, L; Mason, T J

    2015-09-01

    Ultrasound has a wide range of applications in various agricultural sectors. In food processing, it is considered to be an emerging technology with the potential to speed up processes without damaging the quality of foodstuffs. Here we review the reports on the applications of ultrasound specifically with a view to its use in meat processing. Emphasis is placed on the effects on quality and technological properties such as texture, water retention, colour, curing, marinating, cooking yield, freezing, thawing and microbial inhibition. After the literature review it is concluded that ultrasound is a useful tool for the meat industry as it helps in tenderisation, accelerates maturation and mass transfer, reduces cooking energy, increases shelf life of meat without affecting other quality properties, improves functional properties of emulsified products, eases mould cleaning and improves the sterilisation of equipment surfaces.

  8. Clinical applications of doppler ultrasound

    SciTech Connect

    Taylor, K.J.W.; Burns, P.N.; Well, P.N.T.

    1987-01-01

    This book introduces a guide to the physical principles and instrumentation of duplex Doppler ultrasound and its applications in obstetrics, gynecology, neonatology, gastroentology, and evaluation of peripheral vascular disease. The book provides information needed to perform Doppler ultrasound examinations and interpret the results. An introduction to Doppler physics and instrumentation is followed by a thorough review of hemodynamics, which explains the principles underlying interpretation of Doppler signals. Of special note is the state-of-the-art coverage of new applications of Doppler in recognition of high-risk pregnancy, diagnosis of intrauterine growth retardation, investigation of neonatal blood flow, evaluation of first-trimester pregnancy, and diagnosis of gastrointestinal disease. The book also offers guidelines on the use of Doppler ultrasound in diagnosing carotid disease, deep venous thrombosis, and aorta/femoral disease.

  9. Ultrasound technology: A decision-making tool

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An ultrasound demonstration was conducted for participants (~ 110 people) of the Arkansas Cattle Grower’s Conference, Hope, AR. Evaluation of live animals with ultrasound technology allows beef producers the ability to make selection and management decisions. Specifically, ultrasound at the conclu...

  10. Medical Imaging with Ultrasound: Some Basic Physics.

    ERIC Educational Resources Information Center

    Gosling, R.

    1989-01-01

    Discussed are medical applications of ultrasound. The physics of the wave nature of ultrasound including its propagation and production, return by the body, spatial and contrast resolution, attenuation, image formation using pulsed echo ultrasound techniques, measurement of velocity and duplex scanning are described. (YP)

  11. Ultrasound beamforming using compressed data.

    PubMed

    Li, Yen-Feng; Li, Pai-Chi

    2012-05-01

    The rapid advancements in electronics technologies have made software-based beamformers for ultrasound array imaging feasible, thus facilitating the rapid development of high-performance and potentially low-cost systems. However, one challenge to realizing a fully software-based system is transferring data from the analog front end to the software back end at rates of up to a few gigabits per second. This study investigated the use of data compression to reduce the data transfer requirements and optimize the associated trade-off with beamforming quality. JPEG and JPEG2000 compression techniques were adopted. The acoustic data of a line phantom were acquired with a 128-channel array transducer at a center frequency of 3.5 MHz, and the acoustic data of a cyst phantom were acquired with a 64-channel array transducer at a center frequency of 3.33 MHz. The receive-channel data associated with each transmit event are separated into 8 × 8 blocks and several tiles before JPEG and JPEG2000 data compression is applied, respectively. In one scheme, the compression was applied to raw RF data, while in another only the amplitude of baseband data was compressed. The maximum compression ratio of RF data compression to produce an average error of lower than 5 dB was 15 with JPEG compression and 20 with JPEG2000 compression. The image quality is higher with baseband amplitude data compression than with RF data compression; although the maximum overall compression ratio (compared with the original RF data size), which was limited by the data size of uncompressed phase data, was lower than 12, the average error in this case was lower than 1 dB when the compression ratio was lower than 8.

  12. New Ultrasound Modalities in Rheumatology.

    PubMed

    Gutierrez, Marwin; Okano, Tadashi; Reginato, Anthony M; Cazenave, Tomas; Ventura-Rios, Lucio; Bertolazzi, Chiara; Pineda, Carlos

    2015-12-01

    Over the years, ultrasound (US) has accumulated important evidence supporting its relevant role for the assessment of inflammatory processes of different rheumatologic diseases, as well as in the follow-up in assessing the response to different therapeutic approaches. This has been possible because of the increase in training, competency, and knowledge, as well as the rapid progress in the US technologies.Currently, some US machines can be equipped by sophisticated software modalities (i.e., 3-dimensional US, elastosonography, automated cardiovascular software, and fusion imaging) that can augment US traditional role as a safe, fast, and easy-to-perform modality and giving it new life and increased relevance in rheumatology. In this article, we evaluated the US developments, from conventional B-mode to more sophisticated technologies, and their potential clinical impact in the field of rheumatology.Three-dimensional US can improve the accuracy of the assessment of bone erosions and the quantification of power Doppler because of its multiplanar view including coronal, axial and sagital view. Elastosonography is still looking for its role in rheumatology. Preliminary works induce us to consider it as a promise tool for the assessment of tendon pathology and skin of patients with connective tissue disorders. The automated method for the measurement of carotid intima-media thickness permits a rapid and accurate assessment. The preliminary published data showed that it is reliable, and valid compared to the traditional method; they also support the future of rheumatologists as the direct operators in evaluating the cardiovascular risk in daily practice. Fusion imaging increases the diagnostic power of US, displaying simultaneously in the monitor, the US image, and the corresponding computed tomography/magnetic resonance imaging image. However, there are no sufficient data supporting its application in daily rheumatologic practice.

  13. Laparoscopic ultrasound and gastric cancer

    NASA Astrophysics Data System (ADS)

    Dixon, T. Michael; Vu, Huan

    2001-05-01

    The management of gastrointestinal malignancies continues to evolve with the latest available therapeutic and diagnostic modalities. There are currently two driving forces in the management of these cancers: the benefits of minimally invasive surgery so thoroughly demonstrated by laparoscopic surgery, and the shift toward neoadjuvant chemotherapy for upper gastrointestinal cancers. In order to match the appropriate treatment to the disease, accurate staging is imperative. No technological advances have combined these two needs as much as laparascopic ultrasound to evaluate the liver and peritoneal cavity. We present a concise review of the latest application of laparoscopic ultrasound in management of gastrointestinal malignancy.

  14. Ultrasound Imaging and Its Modeling

    NASA Astrophysics Data System (ADS)

    Jensen, Jorgen A.

    Modern medical ultrasound scanners are used to image nearly all soft tissue structures in the body. The anatomy can be studied from gray-scale B-mode images, where the reflectivity and scattering strength of the tissues are displayed. The imaging is performed in real time with 20 to 100 images per second. The technique is widely used, since it does not use ionizing radiation and is safe and painless for the patient. This chapter gives a short introduction to modern ultrasound imaging using array transducers. It includes a description of the different imaging methods, the beam-forming strategies used, and the resulting fields and their modeling.

  15. [Ultrasound examination of hidradenitis suppurativa].

    PubMed

    Martorell, A; Segura Palacios, J M

    2015-11-01

    Hidradenitis suppurativa is a debilitating chronic, recurrent, inflammatory cutaneous disease of the hair follicle that usually presents with painful, deep and inflamed lesions in the areas of the body with apocrine glands, most frequently the axillary, groin and anogenital regions. This entity is difficult to manage since it can be difficult to determine the true nature and extension of the lesions. Cutaneous ultrasound allows real-time visualization of the cutaneous structures under examination, defining the type of lesion, its anatomical extension, and the degree of inflammatory activity, which affects adequate patient management. The present review analyses the importance of ultrasound in the assessment of patients with hidradenitis suppurativa.

  16. Are portable bladder scanning and real-time ultrasound accurate measures of bladder volume in postnatal women?

    PubMed

    Mathew, S; Horne, A W; Murray, L S; Tydeman, G; McKinley, C A

    2007-08-01

    Real-time ultrasound and portable bladder scanners are commonly used instead of catheterisation to determine bladder volumes in postnatal women but it is not known whether these are accurate. Change in bladder volumes measured by ultrasound and portable scanners were compared with actual voided volume (VV) in 100 postnatal women. The VV was on average 41 ml (CI 29 - 54 ml) higher than that measured by ultrasound, and 33 ml (CI 17 - 48 ml) higher than that measured by portable scanners. Portable scanner volumes were 9 ml (CI -8 - 26 ml) higher than those measured by ultrasound. Neither method is an accurate tool for detecting bladder volume in postnatal women.

  17. CT and Ultrasound Guided Stereotactic High Intensity Focused Ultrasound (HIFU)

    SciTech Connect

    Wood, Bradford J.; Frenkel, V.; Viswanathan, A.; Dromi, S.; Oh, K.; Kam, A.; Li, K. C. P.; Yanof, J.; Bauer, C.; Kruecker, J.; Seip, R.

    2006-05-08

    To demonstrate the feasibility of CT and B-mode Ultrasound (US) targeted HIFU, a prototype coaxial focused ultrasound transducer was registered and integrated to a CT scanner. CT and diagnostic ultrasound were used for HIFU targeting and monitoring, with the goals of both thermal ablation and non-thermal enhanced drug delivery. A 1 megahertz coaxial ultrasound transducer was custom fabricated and attached to a passive position-sensing arm and an active six degree-of-freedom robotic arm via a CT stereotactic frame. The outer therapeutic transducer with a 10 cm fixed focal zone was coaxially mounted to an inner diagnostic US transducer (2-4 megahertz, Philips Medical Systems). This coaxial US transducer was connected to a modified commercial focused ultrasound generator (Focus Surgery, Indianapolis, IN) with a maximum total acoustic power of 100 watts. This pre-clinical paradigm was tested for ability to heat tissue in phantoms with monitoring and navigation from CT and live US. The feasibility of navigation via image fusion of CT with other modalities such as PET and MRI was demonstrated. Heated water phantoms were tested for correlation between CT numbers and temperature (for ablation monitoring). The prototype transducer and integrated CT/US imaging system enabled simultaneous multimodality imaging and therapy. Pre-clinical phantom models validated the treatment paradigm and demonstrated integrated multimodality guidance and treatment monitoring. Temperature changes during phantom cooling corresponded to CT number changes. Contrast enhanced or non-enhanced CT numbers may potentially be used to monitor thermal ablation with HIFU. Integrated CT, diagnostic US, and therapeutic focused ultrasound bridges a gap between diagnosis and therapy. Preliminary results show that the multimodality system may represent a relatively inexpensive, accessible, and simple method of both targeting and monitoring HIFU effects. Small animal pre-clinical models may be translated to large

  18. [Abdominal ultrasound course an introduction to the ultrasound technique. Physical basis. Ultrasound language].

    PubMed

    Segura-Grau, A; Sáez-Fernández, A; Rodríguez-Lorenzo, A; Díaz-Rodríguez, N

    2014-01-01

    Ultrasound is a non-invasive, accessible, and versatile diagnostic technique that uses high frequency ultrasound waves to define outline the organs of the human body, with no ionising radiation, in real time and with the capacity to visual several planes. The high diagnostic yield of the technique, together with its ease of uses plus the previously mentioned characteristics, has currently made it a routine method in daily medical practice. It is for this reason that the multidisciplinary character of this technique is being strengthened every day. To be able to perform the technique correctly requires knowledge of the physical basis of ultrasound, the method and the equipment, as well as of the human anatomy, in order to have the maximum information possible to avoid diagnostic errors due to poor interpretation or lack of information.

  19. Acquiring credentials in bedside ultrasound: a cross-sectional survey

    PubMed Central

    Lewiss, Resa E; Saul, Turandot; Del Rios, Marina

    2013-01-01

    Objective Although there are training guidelines to credential emergency physicians in bedside ultrasound, many faculty groups have members who completed residency without a mandatory curriculum. These physicians are therefore required to learn bedside ultrasound while out in practice. The objective of this descriptive report is to illustrate a single academic facility's experience with acquiring credentials for emergency physicians in bedside ultrasound and the faculty's impressions on the motivators of and barriers to completion of the requirements. Design Cross-sectional survey. Setting Two urban teaching hospitals with a combined volume of 170 000 visits a year. Participants 41 emergency medicine attending physicians. Intervention Emergency medicine attending physicians underwent training and credentialing in the applications of aorta and pelvic ultrasound over a 9-month period. Outcome measure After the credentialing period, we conducted a survey to evaluate the physicians’ perceptions of this process. Results There were 41 faculty members during the credentialing survey period. 11 of the faculty members were exempt from ultrasound training. We asked attending physicians (N=41 exempt and non-exempt) to complete a web-based survey after the completion of the credentialing period. Questions about the potential barriers and incentives were listed and responders were asked to rank answers on a five-point Likert scale. Of the 31 respondents, 21 (67.7%) completed the credentialing requirements by the 9-month deadline. 19 of 26 emergency medicine residency trained physicians completed the requirements compared with 2/5 of those that were not emergency medicine residency trained. Our pilot study data suggest an association between fewer years in practice and completion of the requirements. Conclusions This is a report on a single academic institution's experience with a faculty credentialing programme in bedside ultrasound for physicians with a diversity of prior

  20. Cumulative phase delay imaging - A new contrast enhanced ultrasound modality

    SciTech Connect

    Demi, Libertario Sloun, Ruud J. G. van; Mischi, Massimo; Wijkstra, Hessel

    2015-10-28

    Recently, a new acoustic marker for ultrasound contrast agents (UCAs) has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental pressure wave field components is in fact observable for ultrasound propagating through UCAs. This phenomenon is absent in the case of tissue nonlinearity and is dependent on insonating pressure and frequency, UCA concentration, and propagation path length through UCAs. In this paper, ultrasound images based on this marker are presented. The ULA-OP research platform, in combination with a LA332 linear array probe (Esaote, Firenze Italy), were used to image a gelatin phantom containing a PVC plate (used as a reflector) and a cylindrical cavity measuring 7 mm in diameter (placed in between the observation point and the PVC plate). The cavity contained a 240 µL/L SonoVueO{sup ®} UCA concentration. Two insonating frequencies (3 MHz and 2.5 MHz) were used to scan the gelatine phantom. A mechanical index MI = 0.07, measured in water at the cavity location with a HGL-0400 hydrophone (Onda, Sunnyvale, CA), was utilized. Processing the ultrasound signals backscattered from the plate, ultrasound images were generated in a tomographic fashion using the filtered back-projection method. As already observed in previous studies, significantly higher CPD values are measured when imaging at a frequency of 2.5 MHz, as compared to imaging at 3 MHz. In conclusion, these results confirm the applicability of the discussed CPD as a marker for contrast imaging. Comparison with standard contrast-enhanced ultrasound imaging modalities will be the focus of future work.

  1. Pulmonary Capillary Hemorrhage Induced by Fixed-Beam Pulsed Ultrasound.

    PubMed

    Miller, Douglas L; Dou, Chunyan; Raghavendran, Krishnan

    2015-08-01

    The induction of pulmonary capillary hemorrhage (PCH) by pulsed ultrasound was discovered 25 y ago, but early research used fixed-beam systems rather than actual diagnostic ultrasound machines. In this study, results of exposure of rats to fixed-beam focused ultrasound for 5 min at 1.5 and 7.5 MHz were compared with recent research on diagnostic ultrasound. One exposure condition at each frequency used 10-μs pulses delivered at 25-ms intervals. Three conditions involved Gaussian modulation of the pulse amplitudes at 25-ms intervals to simulate diagnostic scanning: 7.5 MHz with 0.3- and 1.5-μs pulses at 100- and 500-μs pulse repetition periods, respectively, and 1.5 MHz with 1.7-μs pulses at 500-μs repetition periods. Four groups were tested for each condition to assess PCH areas at different exposure levels and to determine occurrence thresholds. The conditions with identical pulse timing resulted in smaller PCH areas for the smaller 7.5-MHz beam, but both had thresholds of 0.69-0.75 MPa in situ peak rarefactional pressure amplitude. The Gaussian modulation conditions for both 7.5 MHz with 0.3-μs pulses and 1.5 MHz with 1.7-μs pulses had thresholds of 1.12-1.20 MPa peak rarefactional pressure amplitude, although the relatively long 1.5-μs pulses at 7.5 MHz yielded a threshold of 0.75 MPa. The fixed-beam pulsed ultrasound exposures produced lower thresholds than diagnostic ultrasound. There was no clear tendency for thresholds to increase with increasing ultrasonic frequency when pulse timing conditions were similar.

  2. Measurement of corneal tangent modulus using ultrasound indentation.

    PubMed

    Wang, Li-Ke; Huang, Yan-Ping; Tian, Lei; Kee, Chea-Su; Zheng, Yong-Ping

    2016-09-01

    Biomechanical properties are potential information for the diagnosis of corneal pathologies. An ultrasound indentation probe consisting of a load cell and a miniature ultrasound transducer as indenter was developed to detect the force-indentation relationship of the cornea. The key idea was to utilize the ultrasound transducer to compress the cornea and to ultrasonically measure the corneal deformation with the eyeball overall displacement compensated. Twelve corneal silicone phantoms were fabricated with different stiffness for the validation of measurement with reference to an extension test. In addition, fifteen fresh porcine eyes were measured by the developed system in vitro. The tangent moduli of the corneal phantoms calculated using the ultrasound indentation data agreed well with the results from the tensile test of the corresponding phantom strips (R(2)=0.96). The mean tangent moduli of the porcine corneas measured by the proposed method were 0.089±0.026MPa at intraocular pressure (IOP) of 15mmHg and 0.220±0.053MPa at IOP of 30mmHg, respectively. The coefficient of variation (CV) and intraclass correlation coefficient (ICC) of tangent modulus were 14.4% and 0.765 at 15mmHg, and 8.6% and 0.870 at 30mmHg, respectively. The preliminary study showed that ultrasound indentation could be applied to the measurement of corneal tangent modulus with good repeatability and improved measurement accuracy compared to conventional surface displacement-based measurement method. The ultrasound indentation can be a potential tool for the corneal biomechanical properties measurement in vivo.

  3. Cumulative phase delay imaging - A new contrast enhanced ultrasound modality

    NASA Astrophysics Data System (ADS)

    Demi, Libertario; van Sloun, Ruud J. G.; Wijkstra, Hessel; Mischi, Massimo

    2015-10-01

    Recently, a new acoustic marker for ultrasound contrast agents (UCAs) has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental pressure wave field components is in fact observable for ultrasound propagating through UCAs. This phenomenon is absent in the case of tissue nonlinearity and is dependent on insonating pressure and frequency, UCA concentration, and propagation path length through UCAs. In this paper, ultrasound images based on this marker are presented. The ULA-OP research platform, in combination with a LA332 linear array probe (Esaote, Firenze Italy), were used to image a gelatin phantom containing a PVC plate (used as a reflector) and a cylindrical cavity measuring 7 mm in diameter (placed in between the observation point and the PVC plate). The cavity contained a 240 µL/L SonoVueO® UCA concentration. Two insonating frequencies (3 MHz and 2.5 MHz) were used to scan the gelatine phantom. A mechanical index MI = 0.07, measured in water at the cavity location with a HGL-0400 hydrophone (Onda, Sunnyvale, CA), was utilized. Processing the ultrasound signals backscattered from the plate, ultrasound images were generated in a tomographic fashion using the filtered back-projection method. As already observed in previous studies, significantly higher CPD values are measured when imaging at a frequency of 2.5 MHz, as compared to imaging at 3 MHz. In conclusion, these results confirm the applicability of the discussed CPD as a marker for contrast imaging. Comparison with standard contrast-enhanced ultrasound imaging modalities will be the focus of future work.

  4. Advances in lung ultrasound.

    PubMed

    Francisco, Miguel José; Rahal, Antonio; Vieira, Fabio Augusto Cardillo; Silva, Paulo Savoia Dias da; Funari, Marcelo Buarque de Gusmão

    2016-01-01

    Ultrasound examination of the chest has advanced in recent decades. This imaging modality is currently used to diagnose several pathological conditions and provides qualitative and quantitative information. Acoustic barriers represented by the aerated lungs and the bony framework of the chest generate well-described sonographic artifacts that can be used as diagnostic aids. The normal pleural line and A, B, C, E and Z lines (also known as false B lines) are artifacts with specific characteristics. Lung consolidation and pneumothorax sonographic patterns are also well established. Some scanning protocols have been used in patient management. The Blue, FALLS and C.A.U.S.E. protocols are examples of algorithms using artifact combinations to achieve accurate diagnoses. Combined chest ultrasonography and radiography are often sufficient to diagnose and manage lung and chest wall conditions. Chest ultrasonography is a highly valuable diagnostic tool for radiologists, emergency and intensive care physicians. RESUMO O exame ultrassonográfico do tórax avançou nas últimas décadas, sendo utilizado para o diagnóstico de inúmeras condições patológicas, e fornecendo informações qualitativas e quantitativas. Os pulmões aerados e o arcabouço ósseo do tórax representam barreira sonora para o estudo ultrassonográfico, gerando artefatos que, bem conhecidos, são utilizados como ferramentas diagnósticas. Eco pleural normal, linhas A, linhas B, linhas C, linhas E e Z (conhecidas como falsas linhas B) são artefatos com características peculiares. Os padrões de consolidação e de pneumotórax também são bem estabelecidos. Alguns protocolos têm sido utilizados no manuseio dos pacientes: Blue Protocol, Protocolo FALLS e Protocolo C.A.U.S.E são exemplos de três propostas que, por meio da associação entre os artefatos, permitem sugerir diagnósticos precisos. A ultrassonografia de tórax, aliada à radiografia de tórax, muitas vezes é suficiente para o diagn

  5. A Tactile Sensor for Ultrasound Imaging Systems.

    PubMed

    Peng, Yiyan; Shkel, Yuri M; Hall, Timothy J

    2016-02-15

    Medical ultrasound systems are capable of monitoring a variety of health conditions while avoiding invasive procedures. However this function is complicated by ultrasound contrast of the tissue varying with contact pressure exerted by the probe. The knowledge of the contact pressure is beneficial for a variety of screening and diagnostic procedures involving ultrasound. This paper introduces a solid-state sensor array which measures the contact pressure distribution between the probe and the tissue marginally affecting the ultrasound imaging capabilities. The probe design utilizes the dielectrostriction mechanism which relates the change in dielectric properties of the sensing layer to deformation. The concept, structure, fabrication, and performance of this sensor array are discussed. The prototype device is highly tolerant to overloads (>1 MPa tested) and provides stress measurements in the range of 0.14 to 10 kPa. Its loss of ultrasound transmissivity is less 3dB at 9 MHz ultrasound frequency. This performance is satisfactory for clinical and biomedical research in ultrasound image formation and interpretation, however for commercial product, a higher ultrasound transmissivity is desired. Directions for improving the sensor ultrasound transparency and electrical performance are discussed. The sensor array described in this paper has been developed specifically for ultrasound diagnosis during breast cancer screening. However, the same sensing mechanism, similar configuration and sensor array structure can be applied to other applications involving ultrasound tools for medical diagnostics.

  6. A Tactile Sensor for Ultrasound Imaging Systems

    PubMed Central

    Peng, Yiyan; Shkel, Yuri M.; Hall, Timothy J.

    2015-01-01

    Medical ultrasound systems are capable of monitoring a variety of health conditions while avoiding invasive procedures. However this function is complicated by ultrasound contrast of the tissue varying with contact pressure exerted by the probe. The knowledge of the contact pressure is beneficial for a variety of screening and diagnostic procedures involving ultrasound. This paper introduces a solid-state sensor array which measures the contact pressure distribution between the probe and the tissue marginally affecting the ultrasound imaging capabilities. The probe design utilizes the dielectrostriction mechanism which relates the change in dielectric properties of the sensing layer to deformation. The concept, structure, fabrication, and performance of this sensor array are discussed. The prototype device is highly tolerant to overloads (>1 MPa tested) and provides stress measurements in the range of 0.14 to 10 kPa. Its loss of ultrasound transmissivity is less 3dB at 9 MHz ultrasound frequency. This performance is satisfactory for clinical and biomedical research in ultrasound image formation and interpretation, however for commercial product, a higher ultrasound transmissivity is desired. Directions for improving the sensor ultrasound transparency and electrical performance are discussed. The sensor array described in this paper has been developed specifically for ultrasound diagnosis during breast cancer screening. However, the same sensing mechanism, similar configuration and sensor array structure can be applied to other applications involving ultrasound tools for medical diagnostics. PMID:26880870

  7. Calibration and Evaluation of Ultrasound Thermography Using Infrared Imaging.

    PubMed

    Hsiao, Yi-Sing; Deng, Cheri X

    2016-02-01

    Real-time monitoring of the spatiotemporal evolution of tissue temperature is important to ensure safe and effective treatment in thermal therapies including hyperthermia and thermal ablation. Ultrasound thermography has been proposed as a non-invasive technique for temperature measurement, and accurate calibration of the temperature-dependent ultrasound signal changes against temperature is required. Here we report a method that uses infrared thermography for calibration and validation of ultrasound thermography. Using phantoms and cardiac tissue specimens subjected to high-intensity focused ultrasound heating, we simultaneously acquired ultrasound and infrared imaging data from the same surface plane of a sample. The commonly used echo time shift-based method was chosen to compute ultrasound thermometry. We first correlated the ultrasound echo time shifts with infrared-measured temperatures for material-dependent calibration and found that the calibration coefficient was positive for fat-mimicking phantom (1.49 ± 0.27) but negative for tissue-mimicking phantom (-0.59 ± 0.08) and cardiac tissue (-0.69 ± 0.18°C-mm/ns). We then obtained the estimation error of the ultrasound thermometry by comparing against the infrared-measured temperature and revealed that the error increased with decreased size of the heated region. Consistent with previous findings, the echo time shifts were no longer linearly dependent on temperature beyond 45°C-50°C in cardiac tissues. Unlike previous studies in which thermocouples or water bath techniques were used to evaluate the performance of ultrasound thermography, our results indicate that high-resolution infrared thermography is a useful tool that can be applied to evaluate and understand the limitations of ultrasound thermography methods.

  8. A super-resolution ultrasound method for brain vascular mapping

    PubMed Central

    O'Reilly, Meaghan A.; Hynynen, Kullervo

    2013-01-01

    Purpose: High-resolution vascular imaging has not been achieved in the brain due to limitations of current clinical imaging modalities. The authors present a method for transcranial ultrasound imaging of single micrometer-size bubbles within a tube phantom. Methods: Emissions from single bubbles within a tube phantom were mapped through an ex vivo human skull using a sparse hemispherical receiver array and a passive beamforming algorithm. Noninvasive phase and amplitude correction techniques were applied to compensate for the aberrating effects of the skull bone. The positions of the individual bubbles were estimated beyond the diffraction limit of ultrasound to produce a super-resolution image of the tube phantom, which was compared with microcomputed tomography (micro-CT). Results: The resulting super-resolution ultrasound image is comparable to results obtained via the micro-CT for small tissue specimen imaging. Conclusions: This method provides superior resolution to deep-tissue contrast ultrasound and has the potential to be extended to provide complete vascular network imaging in the brain. PMID:24320408

  9. Quality Improvement of Liver Ultrasound Images Using Fuzzy Techniques

    PubMed Central

    Bayani, Azadeh; Langarizadeh, Mostafa; Radmard, Amir Reza; Nejad, Ahmadreza Farzaneh

    2016-01-01

    Background: Liver ultrasound images are so common and are applied so often to diagnose diffuse liver diseases like fatty liver. However, the low quality of such images makes it difficult to analyze them and diagnose diseases. The purpose of this study, therefore, is to improve the contrast and quality of liver ultrasound images. Methods: In this study, a number of image contrast enhancement algorithms which are based on fuzzy logic were applied to liver ultrasound images - in which the view of kidney is observable - using Matlab2013b to improve the image contrast and quality which has a fuzzy definition; just like image contrast improvement algorithms using a fuzzy intensification operator, contrast improvement algorithms applying fuzzy image histogram hyperbolization, and contrast improvement algorithms by fuzzy IF-THEN rules. Results: With the measurement of Mean Squared Error and Peak Signal to Noise Ratio obtained from different images, fuzzy methods provided better results, and their implementation - compared with histogram equalization method - led both to the improvement of contrast and visual quality of images and to the improvement of liver segmentation algorithms results in images. Conclusion: Comparison of the four algorithms revealed the power of fuzzy logic in improving image contrast compared with traditional image processing algorithms. Moreover, contrast improvement algorithm based on a fuzzy intensification operator was selected as the strongest algorithm considering the measured indicators. This method can also be used in future studies on other ultrasound images for quality improvement and other image processing and analysis applications. PMID:28077898

  10. Coherent photoacoustic-ultrasound correlation and imaging.

    PubMed

    Gao, Fei; Feng, Xiaohua; Zheng, Yuanjin

    2014-09-01

    Both photoacoustics and ultrasound have been researched extensively but separately. In this letter, we report an initial study on the coherent correlation between pulsed photoacoustic wave and pulse-echo ultrasound wave. By illuminating an object with a pulsed laser and external ultrasound sequentially, both the endogenous photoacoustic wave and pulse-echo ultrasound wave are received and coherently correlated, demonstrating enhanced signal-to-noise ratio. Image contrast of the proposed coherent photoacoustic-ultrasound imaging is also demonstrated to be improved significantly on vessel-mimicking phantom, due to fusion of the optical absorption and ultrasound reflection contrasts by coherent correlation of either conventional laser-induced photoacoustic imaging or pulse-echo ultrasound imaging separately.

  11. Combination effect of ultrasound and shake as a mechanical action for textile cleaning.

    PubMed

    Gotoh, Keiko; Harayama, Kokoro; Handa, Keiko

    2015-01-01

    The ultrasonic cleaning of artificially soiled fabrics with and without shake was carried out in an aqueous anionic surfactant solution. The polyester, cotton and polyester/cotton (65/35) fabrics were soiled with oleic acid or carbon black as a model soil, and cleaned together with their original fabrics with applying ultrasound for 5min. The detergency and the soil redeposition were determined from the change in the Kubelka-Munk function of the soiled and original fabric surfaces due to the cleaning. For any fabric, the removal of oleic acid and carbon black from the soiled fabric and their redeposition onto the original fabric increased with increasing electric power consumption of ultrasound. When ultrasound and shake were applied at the same time, the detergency further increased for any electric power consumption. The maximum detergency obtained with combination of ultrasound 340W and shake 160spm was compared with detergency obtained with Wascator, a horizontal axis drum type washer. It was found that the ultrasound/shake combination cleaning enabled efficient removal of both soils from any fabric and the detergency of the polyester fabrics was comparable to that with Wascator. The mechanical action during the washing was evaluated by two mechanical action test pieces commercially available, which indicated that the ultrasound/shake combination cleaning provided gentle mechanical action to the fabric in comparison with the drum type washer. The SEM observations showed the damage of the fabric and fiber surfaces was negligibly small after the ultrasound/shake combination washing.

  12. Effects of deep heating provided by therapeutic ultrasound on demyelinating nerves

    PubMed Central

    Aydin, Elif; Tastaban, Engin; Omurlu, Imran Kurt; Turan, Yasemin; Şendur, Ömer Faruk

    2016-01-01

    [Purpose] Physiotherapeutic heating agents are classified into two groups: superficial-heating agents and deep-heating agents. Therapeutic ultrasound is a deep-heating agent used to treat various musculosketal disorders. Numerous studies have attempted to determine the impact of ultrasound on healthy nerve conduction parameters. However, the instantaneous effects of deep heating via ultrasound on demyelinating nerves do not appear to have been described previously. The present study aimed to assess and compare the impact of ultrasound on demyelinating nerve and healthy nerve conduction parameters. [Subjects and Methods] Carpal tunnel syndrome was used as a focal demyelination model. Thirty-two hands of 25 participants with carpal tunnel syndrome were enrolled in the study. Ultrasound parameters were 3.3 MHz, 1.0 W/cm2, 8 minutes, and continuous wave. Electrodiagnostic studies were performed initially, at the midpoint (4th min), and immediately after (8th min) ultrasound application. [Results] Reduced motor conduction velocity was found in demyelinating nerves at the 4th and 8th minutes. Ulnar nerve onset latency was significantly prolonged in the 8th minute recording, compared to the initial value. There were no significant differences in relative velocity and latency changes between demyelinating and normal nerves. [Conclusion] Deep heating via ultrasound may inversely affect conduction velocity in demyelinating nerves. PMID:27190467

  13. Development of a custom biological scaffold for investigating ultrasound-mediated intracellular delivery.

    PubMed

    Bui, Loan; Aleid, Adham; Alassaf, Ahmad; Wilson, Otto C; Raub, Christopher B; Frenkel, Victor

    2017-01-01

    In vitro investigations of ultrasound mediated, intracellular drug and gene delivery (i.e. sonoporation) are typically carried out in cells cultured in standard plastic well plates. This creates conditions that poorly resemble in vivo conditions, as well as generating unwanted ultrasound phenomena that may confound the interpretation of results. Here, we present our results in the development of a biological scaffold for sonoporation studies. The scaffolds were comprised of cellulose fibers coated with chitosan and gelatin. Scaffold formulation was optimized for adherence and proliferation of mouse fibroblasts in terms of the ratio and relative concentration of the two constituents. The scaffolds were also shown to significantly reduce ultrasound reflections compared to the plastic well plates. A custom treatment chamber was designed and built, and the occurrence of acoustic cavitation in the chamber during the ultrasound treatments was detected; a requirement for the process of sonoporation. Finally, experiments were carried out to optimize the ultrasound exposures to minimize cellular damage. Ultrasound exposure was then shown to enable the uptake of 100nm fluorescently labeled polystyrene nanoparticles in suspension into the cells seeded on scaffolds, compared to incubation of cell-seeded scaffolds with nanoparticles alone. These preliminary results set the basis for further development of this platform. They also provide motivation for the development of similar platforms for the controlled investigation of other ultrasound mediated cell and tissue therapies.

  14. Characterization of controlled bone defects using 2D and 3D ultrasound imaging techniques.

    PubMed

    Parmar, Biren J; Longsine, Whitney; Sabonghy, Eric P; Han, Arum; Tasciotti, Ennio; Weiner, Bradley K; Ferrari, Mauro; Righetti, Raffaella

    2010-08-21

    Ultrasound is emerging as an attractive alternative modality to standard x-ray and CT methods for bone assessment applications. As of today, however, there is a lack of systematic studies that investigate the performance of diagnostic ultrasound techniques in bone imaging applications. This study aims at understanding the performance limitations of new ultrasound techniques for imaging bones in controlled experiments in vitro. Experiments are performed on samples of mammalian and non-mammalian bones with controlled defects with size ranging from 400 microm to 5 mm. Ultrasound findings are statistically compared with those obtained from the same samples using standard x-ray imaging modalities and optical microscopy. The results of this study demonstrate that it is feasible to use diagnostic ultrasound imaging techniques to assess sub-millimeter bone defects in real time and with high accuracy and precision. These results also demonstrate that ultrasound imaging techniques perform comparably better than x-ray imaging and optical imaging methods, in the assessment of a wide range of controlled defects both in mammalian and non-mammalian bones. In the future, ultrasound imaging techniques might provide a cost-effective, real-time, safe and portable diagnostic tool for bone imaging applications.

  15. Medical ultrasound education for bioengineers

    NASA Astrophysics Data System (ADS)

    Vaezy, Shahram

    2005-04-01

    The widespread adoption of ultrasound technologies in medicine has necessitated the development of educational programs to address the growing demand for trained expertise in both academia and industry. The demand has been especially great in the field of therapeutic ultrasound that has experienced a significant level of research and development activities in the past decade. The applications cover a wide range including cancer treatment, hemorrhage control, cardiac ablation, gene therapy, and cosmetic surgery. A comprehensive educational program in ultrasound is well suited for bioengineering departments at colleges and universities. Our educational program for students in Bioengineering at the University of Washington includes a year-long coursework covering theory and practice of ultrasound, conducting research projects, attending and presenting at weekly seminars on literature survey, presentations at scientific meetings, and attending specialized workshops offered by various institutions for specific topics. An important aspect of this training is its multi-disciplinary approach, encompassing science, engineering, and medicine. The students are required to build teams with expertise in these disciplines. Our experience shows that these students are well prepared for careers in academia, conducting cutting edge research, as well as industry, being involved in the transformation of research end-products to commercially viable technology.

  16. [Use of ultrasound in ophthalmology].

    PubMed

    Trier, H G

    1982-12-01

    In ophthalmology, ultrasound is applied in diagnostics as well as in surgery and therapy. This paper gives a short survey on both applications. Ultrasonic phacoemulsification is of considerable practical importance for modern cataract micro-surgery with intraocular lens implantation. Applications of that kind require consideration of ultrasonic bioeffects and equipment safety. Diagnostic use of ultrasound includes biometry (echometry), tissue examination and characterization, and vascular investigations in eye and orbit. The application of diagnostic ultrasound on in-patients, its individual indications, and the appropriate methods (A, B, automatic biometric devices for axial length measuring, M, Doppler) are described. Examples of commercially available instruments for the different applications are given. In comparison with other disciplines ophthalmic A-mode and B-mode echography is characterized by: refined depth resolution and lateral resolution; the important part of quantitative methods for clinical evaluation of echograms; and the advanced level of quality assurance for equipment performance. Refined tissue evaluation requires optimized and reproducible equipment parameters. To ensure these conditions the clinical echographer must be educated and willing to test performance and quality of his equipment. Finally, a perspective of actual research in diagnostic ultrasound of the eye is given.

  17. Ultrasound mediated nanoparticle drug delivery

    NASA Astrophysics Data System (ADS)

    Mullin, Lee B.

    Ultrasound is not only a powerful diagnostic tool, but also a promising therapeutic technology that can be used to improve localized drug delivery. Microbubble contrast agents are micron sized encapsulated gas filled bubbles that are administered intravenously. Originally developed to enhance ultrasound images, microbubbles are highly echogenic due to the gas core that provides a detectable impedance difference from the surrounding medium. The core also allows for controlled response of the microbubbles to ultrasound pulses. Microbubbles can be pushed using acoustic radiation force and ruptured using high pressures. Destruction of microbubbles can increase permeability at the cellular and vascular level, which can be advantageous for drug delivery. Advances in drug delivery methods have been seen with the introduction of nanoparticles, nanometer sized objects often carrying a drug payload. In chemotherapy, nanoparticles can deliver drugs to tumors while limiting systemic exposure due to abnormalities in tumor vasculature such large gaps between endothelial cells that allow nanoparticles to enter into the interstitial space; this is referred to as the enhanced permeability and retention (EPR) effect. However, this effect may be overestimated in many tumors. Additionally, only a small percentage of the injected dose accumulates in the tumor, which most the nanoparticles accumulating in the liver and spleen. It is hypothesized that combining the acoustic activity of an ultrasound contrast agent with the high payload and extravasation ability of a nanoparticle, localized delivery to the tumor with reduced systemic toxicity can be achieved. This method can be accomplished by either loading nanoparticles onto the shell of the microbubble or through a coadministration method of both nanoparticles and microbubbles. The work presented in this dissertation utilizes novel and commercial nanoparticle formulations, combined with microbubbles and a variety of ultrasound systems

  18. The Effects of Practicing with a Virtual Ultrasound Trainer on FAST Window Identification, Acquisition, and Diagnosis. CRESST Report 787

    ERIC Educational Resources Information Center

    Chung, Gregory K. W. K.; Gyllenhammer, Ruth G.; Baker, Eva L.

    2011-01-01

    In this study, we compared the effects of simulator-based virtual ultrasound scanning practice to classroom-based hands-on ultrasound scanning practice on participants' knowledge of FAST window quadrants and interpretation, and on participants' performance on live patient FAST exams. Twenty-five novice participants were randomly assigned to the…

  19. Micro-ultrasound for preclinical imaging

    PubMed Central

    Foster, F. Stuart; Hossack, John; Adamson, S. Lee

    2011-01-01

    Over the past decade, non-invasive preclinical imaging has emerged as an important tool to facilitate biomedical discovery. Not only have the markets for these tools accelerated, but the numbers of peer-reviewed papers in which imaging end points and biomarkers have been used have grown dramatically. High frequency ‘micro-ultrasound’ has steadily evolved in the post-genomic era as a rapid, comparatively inexpensive imaging tool for studying normal development and models of human disease in small animals. One of the fundamental barriers to this development was the technological hurdle associated with high-frequency array transducers. Recently, new approaches have enabled the upper limits of linear and phased arrays to be pushed from about 20 to over 50 MHz enabling a broad range of new applications. The innovations leading to the new transducer technology and scanner architecture are reviewed. Applications of preclinical micro-ultrasound are explored for developmental biology, cancer, and cardiovascular disease. With respect to the future, the latest developments in high-frequency ultrasound imaging are described. PMID:22866232

  20. Hepatic lesions segmentation in ultrasound nonlinear imaging

    NASA Astrophysics Data System (ADS)

    Kissi, Adelaide A.; Cormier, Stephane; Pourcelot, Leandre; Tranquart, Francois

    2005-04-01

    Doppler has been used for many years for cardiovascular exploration in order to visualize the vessels walls and anatomical or functional diseases. The use of ultrasound contrast agents makes it possible to improve ultrasonic information. Nonlinear ultrasound imaging highlights the detection of these agents within an organ and hence is a powerful technique to image perfusion of an organ in real-time. The visualization of flow and perfusion provides important information for the diagnosis of various diseases as well as for the detection of tumors. However, the images are buried in noise, the speckle, inherent in the image formation. Furthermore at portal phase, there is often an absence of clear contrast between lesions and surrounding tissues because the organ is filled with agents. In this context, we propose a new method of automatic liver lesions segmentation in nonlinear imaging sequences for the quantification of perfusion. Our method of segmentation is divided into two stages. Initially, we developed an anisotropic diffusion step which raised the structural characteristics to eliminate the speckle. Then, a fuzzy competitive clustering process allowed us to delineate liver lesions. This method has been used to detect focal hepatic lesions (metastasis, nodular hyperplasia, adenoma). Compared to medical expert"s report obtained on 15 varied lesions, the automatic segmentation allows us to identify and delineate focal liver lesions during the portal phase which high accuracy. Our results show that this method improves markedly the recognition of focal hepatic lesions and opens the way for future precise quantification of contrast enhancement.

  1. Ultrasound evaluation of centenarians' gallbladder.

    PubMed

    Romano, Marcello; Batticani, Santa; Pistone, Giovanni; Malaguarnera, Mariano

    2004-02-01

    Background: Ultrasound (US) examination of gallbladder is considered to be reliable, both in morphological and functional evaluation. We used US to study the gallbladder of a series of centenarians in order to show the characteristics of this organ in these subjects. We then compared the data obtained with two control populations omposed of elderly and adult subjects, respectively. Methods: US examination was done after an overnight fast and after emptying the gallbladder at 15-min intervals for a period of 90 min. To induce emptying of the gallbladder, we chose a semisolid meal with a small caloric value (370 kcal). The following parameters were evaluated: fasting gallbladder volume (in milliliters) before administration of the meal (considered to be 100%); gallbladder emptying (according to the formula: fasting gallbladder volume minus post-meal gallbladder volume at 10-min intervals divided by fasting gallbladder volume: the result of this operation was multiplied by 100); gallbladder motor functions, such as ejection volume (ml), is considered as the difference between fasting gallbladder volume and residual volume; ejection fraction (%), considered as the difference between fasting gallbladder volume and residual volume, is expressed as percentage fasting volume; and ejection rate (%/min) is calculated by dividing ejection fraction by time requested to reach the residual volume. Results: We found a common bile duct diameter that was significantly higher in centenarians than in the elderly and adults. Gallbladder wall thickness was significantly higher in centenarians than in adults. We also found substantially significant differences between centenarians with and without gallstones and elderly and adult subjects in the following parameters: mean gallbladder volume (reduced), residual volume (reduced), ejection volume (reduced) and ejection rate (reduced). The differences were not significant for the ejection fraction, and they were slightly reduced in

  2. Nonlinear acoustics in biomedical ultrasound

    NASA Astrophysics Data System (ADS)

    Cleveland, Robin O.

    2015-10-01

    Ultrasound is widely used to image inside the body; it is also used therapeutically to treat certain medical conditions. In both imaging and therapy applications the amplitudes employed in biomedical ultrasound are often high enough that nonlinear acoustic effects are present in the propagation: the effects have the potential to be advantageous in some scenarios but a hindrance in others. In the case of ultrasound imaging the nonlinearity produces higher harmonics that result in images of greater quality. However, nonlinear effects interfere with the imaging of ultrasound contrast agents (typically micron sized bubbles with a strong nonlinear response of their own) and nonlinear effects also result in complications when derating of pressure measurements in water to in situ values in tissue. High intensity focused ultrasound (HIFU) is emerging as a non-invasive therapeutic modality which can result in thermal ablation of tissue. For thermal ablation, the extra effective attenuation resulting from nonlinear effects can result in enhanced heating of tissue if shock formation occurs in the target region for ablation - a highly desirable effect. However, if nonlinearity is too strong it can also result in undesired near-field heating and reduced ablation in the target region. The disruption of tissue (histotripsy) and fragmentation of kidney stones (lithotripsy) exploits shock waves to produce mechanically based effects, with minimal heating present. In these scenarios it is necessary for the waves to be of sufficient amplitude that a shock exists when the waveform reaches the target region. This talk will discuss how underlying nonlinear phenomenon act in all the diagnostic and therapeutic applications described above.

  3. Visualizing ultrasound through computational modeling

    NASA Technical Reports Server (NTRS)

    Guo, Theresa W.

    2004-01-01

    The Doppler Ultrasound Hematocrit Project (DHP) hopes to find non-invasive methods of determining a person s blood characteristics. Because of the limits of microgravity and the space travel environment, it is important to find non-invasive methods of evaluating the health of persons in space. Presently, there is no well developed method of determining blood composition non-invasively. This projects hopes to use ultrasound and Doppler signals to evaluate the characteristic of hematocrit, the percentage by volume of red blood cells within whole blood. These non-invasive techniques may also be developed to be used on earth for trauma patients where invasive measure might be detrimental. Computational modeling is a useful tool for collecting preliminary information and predictions for the laboratory research. We hope to find and develop a computer program that will be able to simulate the ultrasound signals the project will work with. Simulated models of test conditions will more easily show what might be expected from laboratory results thus help the research group make informed decisions before and during experimentation. There are several existing Matlab based computer programs available, designed to interpret and simulate ultrasound signals. These programs will be evaluated to find which is best suited for the project needs. The criteria of evaluation that will be used are 1) the program must be able to specify transducer properties and specify transmitting and receiving signals, 2) the program must be able to simulate ultrasound signals through different attenuating mediums, 3) the program must be able to process moving targets in order to simulate the Doppler effects that are associated with blood flow, 4) the program should be user friendly and adaptable to various models. After a computer program is chosen, two simulation models will be constructed. These models will simulate and interpret an RF data signal and a Doppler signal.

  4. Rock expansion caused by ultrasound

    NASA Astrophysics Data System (ADS)

    Hedberg, C.; Gray, A.

    2013-12-01

    It has during many years been reported that materials' elastic modulus decrease when exposed to influences like mechanical impacts, ultrasound, magnetic fields, electricity and even humidity. Non-perfect atomic structures like rocks, concrete, or damaged metals exhibit a larger effect. This softening has most often been recorded by wave resonance measurements. The motion towards equilibrium is slow - often taking hours or days, which is why the effect is called Slow Dynamics [1]. The question had been raised, if a material expansion also occurs. 'The most fundamental parameter to consider is the volume expansion predicted to occur when positive hole charge carriers become activated, causing a decrease of the electron density in the O2- sublattice of the rock-forming minerals. This decrease of electron density should affect essentially all physical parameters, including the volume.' [2]. A new type of configuration has measured expansion of a rock subjected to ultrasound. A PZT was used as a pressure sensor while the combined thickness of the rock sample and the PZT sensor was held fixed. The expansion increased the stress in both the rock and the PZT, which gave an out-put voltage from the PZT. Knowing its material properties then made it possible to calculate the rock expansion. The equivalent strain caused by the ultrasound was approximately 3 x 10-5. The temperature was monitored and accounted for during the tests and for the maximum expansion the increase was 0.7 C, which means the expansion is at least to some degree caused by heating of the material by the ultrasound. The fraction of bonds activated by ultrasound was estimated to be around 10-5. References: [1] Guyer, R.A., Johnson, P.A.: Nonlinear Mesoscopic Elasticity: The Complex Behaviour of Rocks, Soils, Concrete. Wiley-VCH 2009 [2] M.M. Freund, F.F. Freund, Manipulating the Toughness of Rocks through Electric Potentials, Final Report CIF 2011 Award NNX11AJ84A, NAS Ames 2012.

  5. Torsional ultrasound mode versus combined torsional and conventional ultrasound mode phacoemulsification for eyes with hard cataract

    PubMed Central

    Fakhry, Mohamed A; Shazly, Malak I El

    2011-01-01

    Purpose To compare torsional versus combined torsional and conventional ultrasound modes in hard cataract surgery regarding ultrasound energy and time and effect on corneal endothelium. Settings Kasr El Aini hospital, Cairo University, and International Eye Hospital, Cairo, Egypt. Methodology Ninety-eight eyes of 63 patients were enrolled in this prospective comparative randomized masked clinical study. All eyes had nuclear cataracts of grades III and IV using the Lens Opacities Classification System III (LOCS III). Two groups were included, each having an equal number of eyes (49). The treatment for group A was combined torsional and conventional US mode phacoemulsification, and for group B torsional US mode phacoemulsification only. Pre- and post-operative assessments included best corrected visual acuity (BCVA), intraocular pressure (IOP), slit-lamp evaluation, and fundoscopic evaluation. Endothelial cell density (ECD) and central corneal thickness (CCT) were measured preoperatively, 1 day, 7 days, and 1 month postoperatively. All eyes were operated on using the Alcon Infiniti System (Alcon, Fort Worth, TX) with the quick chop technique. All eyes were implanted with AcrySof SA60AT (Alcon) intraocular lens (IOL). The main phaco outcome parameters included the mean ultrasound time (UST), the mean cumulative dissipated energy (CDE), and the percent of average torsional amplitude in position 3 (%TUSiP3). Results Improvement in BCVA was statistically significant in both groups (P < 0.001). Comparing UST and CDE for both groups revealed results favoring the pure torsional group (P = 0.002 and P < 0.001 for UST; P = 0.058 and P = 0.009 for CDE). As for %TUSiP3, readings were higher for the pure torsional group (P = 0.03 and P = 0.01). All changes of CCT, and ECD over time were found statistically significant using one-way ANOVA testing (P < 0.001). Conclusion Both modes are safe in hard cataract surgery, however the pure torsional mode showed less US energy used. PMID

  6. In-line positioning of ultrasound images using wireless remote display system with tablet computer facilitates ultrasound-guided radial artery catheterization.

    PubMed

    Tsuchiya, Masahiko; Mizutani, Koh; Funai, Yusuke; Nakamoto, Tatsuo

    2016-02-01

    Ultrasound-guided procedures may be easier to perform when the operator's eye axis, needle puncture site, and ultrasound image display form a straight line in the puncture direction. However, such methods have not been well tested in clinical settings because that arrangement is often impossible due to limited space in the operating room. We developed a wireless remote display system for ultrasound devices using a tablet computer (iPad Mini), which allows easy display of images at nearly any location chosen by the operator. We hypothesized that the in-line layout of ultrasound images provided by this system would allow for secure and quick catheterization of the radial artery. We enrolled first-year medical interns (n = 20) who had no prior experience with ultrasound-guided radial artery catheterization to perform that using a short-axis out-of-plane approach with two different methods. With the conventional method, only the ultrasound machine placed at the side of the head of the patient across the targeted forearm was utilized. With the tablet method, the ultrasound images were displayed on an iPad Mini positioned on the arm in alignment with the operator's eye axis and needle puncture direction. The success rate and time required for catheterization were compared between the two methods. Success rate was significantly higher (100 vs. 70 %, P = 0.02) and catheterization time significantly shorter (28.5 ± 7.5 vs. 68.2 ± 14.3 s, P < 0.001) with the tablet method as compared to the conventional method. An ergonomic straight arrangement of the image display is crucial for successful and quick completion of ultrasound-guided arterial catheterization. The present remote display system is a practical method for providing such an arrangement.

  7. SU-E-J-118: Verification of Intrafractional Positional Accuracy Using Ultrasound Autoscan Tracking for Prostate Cancer Treatment

    SciTech Connect

    Yu, S; Hristov, D; Phillips, T

    2014-06-01

    Purpose: Transperineal ultrasound imaging is attractive option for imageguided radiation therapy as there is no need to implant fiducials, no extra imaging dose, and real time continuous imaging is possible during treatment. The aim of this study is to verify the tracking accuracy of a commercial ultrasound system under treatment conditions with a male pelvic phantom. Methods: A CT and ultrasound scan were acquired for the male pelvic phantom. The phantom was then placed in a treatment mimicking position on a motion platform. The axial and lateral tracking accuracy of the ultrasound system were verified using an independent optical tracking system. The tracking accuracy was evaluated by tracking the phantom position detected by the ultrasound system, and comparing it to the optical tracking system under the conditions of beam on (15 MV), beam off, poor image quality with an acoustic shadow introduced, and different phantom motion cycles (10 and 20 second periods). Additionally, the time lag between the ultrasound-detected and actual phantom motion was investigated. Results: Displacement amplitudes reported by the ultrasound system and optical system were within 0.5 mm of each other for both directions and all conditions. The ultrasound tracking performance in axial direction was better than in lateral direction. Radiation did not interfere with ultrasound tracking while image quality affected tracking accuracy. The tracking accuracy was better for periodic motion with 20 second period. The time delay between the ultrasound tracking system and the phantom motion was clinically acceptable. Conclusion: Intrafractional prostate motion is a potential source of treatment error especially in the context of emerging SBRT regimens. It is feasible to use transperineal ultrasound daily to monitor prostate motion during treatment. Our results verify the tracking accuracy of a commercial ultrasound system to be better than 1 mm under typical external beam treatment conditions.

  8. Standardized ultrasound hepatic/renal ratio and hepatic attenuation rate to quantify liver fat content: an improvement method.

    PubMed

    Xia, Ming-Feng; Yan, Hong-Mei; He, Wan-Yuan; Li, Xiao-Ming; Li, Chao-Lun; Yao, Xiu-Zhong; Li, Ruo-Kun; Zeng, Meng-Su; Gao, Xin

    2012-02-01

    Accurate measures of liver fat content are essential for investigating the role of hepatic steatosis in the pathophysiology of multiple metabolic disorders. No traditional imaging methods can accurately quantify liver fat content. [(1)H]-magnetic resonance spectroscopy (MRS) is restricted in large-scale studies because of the practical and technological issues. Previous attempts on computer-aided ultrasound quantification of liver fat content varied in method, and the ultrasound quantitative parameters measured from different ultrasound machines were hardly comparable. We aimed to establish and validate a simple and propagable method for quantitative assessment of liver fat content based on the combination of standardized ultrasound quantitative parameters, using [(1)H]-MRS as gold standard. Totally 127 participants were examined with both ultrasonography (US) and [(1)H]-MRS. Ultrasound hepatic/renal echo-intensity ratio (H/R) and ultrasound hepatic echo-intensity attenuation rate (HA) were obtained from ordinary ultrasound images using computer program. Both parameters were standardized using a tissue-mimicking phantom before analysis. Standardized ultrasound H/R and HA were positively correlated with the liver fat content by [(1)H]-MRS (r = 0.884, P < 0.001 and r = 0.711, P < 0.001, respectively). Linear regression analysis showed ultrasound H/R could modestly predict the amount of liver fat (adjusted explained variance 78.0%, P < 0.001). The addition of ultrasound HA slightly improved the adjusted explained variance to 79.8%. Difference of estimated liver fat contents between different ultrasound machines and operators was reasonably well. Thus, computer-aided US is a valid method to estimate liver fat content and can be applied extensively after standardization of ultrasound quantitative parameters.

  9. Analgesic effect of extracorporeal shock wave therapy versus ultrasound therapy in chronic tennis elbow

    PubMed Central

    Lizis, Paweł

    2015-01-01

    [Purpose] This study compared the analgesic effects of extracorporeal shock wave therapy with those of ultrasound therapy in patients with chronic tennis elbow. [Subjects] Fifty patients with tennis elbow were randomized to receive extracorporeal shock wave therapy or ultrasound therapy. [Methods] The extracorporeal shock wave therapy group received 5 treatments once per week. Meanwhile, the ultrasound group received 10 treatments 3 times per week. Pain was assessed using the visual analogue scale during grip strength evaluation, palpation of the lateral epicondyle, Thomsen test, and chair test. Resting pain was also recorded. The scores were recorded and compared within and between groups pre-treatment, immediately post-treatment, and 3 months post-treatment. [Results] Intra- and intergroup comparisons immediately and 3 months post-treatment showed extracorporeal shock wave therapy decreased pain to a significantly greater extent than ultrasound therapy. [Conclusion] Extracorporeal shock wave therapy can significantly reduce pain in patients with chronic tennis elbow. PMID:26357440

  10. Ultrasound microscope: the new field in ultrasound diagnostics

    NASA Astrophysics Data System (ADS)

    Novyc'kyy, Victor V.; Lushchyk, Ulyana B.

    2001-06-01

    A device which is a new stage in the development of medical equipment has been developed. The device works as an ultrasound microscope in vivo and provides 4 up to 32 colored histological image. It gives possibility to estimate tissue acoustic density with the help of 4 up to 32 gradation coloring different tissues and enables tissue microcirculation visualization. With the help of the device a doctor can objectify fatty hepatitis and cirrhosis, edema of different organs and tissues as well as microcirculation in organs and tissues (e.g. muscles, myocard and bone system). New promising applications of ultrasound systems in diagnostics and for choosing individual treatment tactics, with pathogenesis being taken into account, may be developed with the help of the device.

  11. Ultrasound assisted biodiesel production from sesame (Sesamum indicum L.) oil using barium hydroxide as a heterogeneous catalyst: Comparative assessment of prediction abilities between response surface methodology (RSM) and artificial neural network (ANN).

    PubMed

    Sarve, Antaram; Sonawane, Shriram S; Varma, Mahesh N

    2015-09-01

    The present study estimates the prediction capability of response surface methodology (RSM) and artificial neural network (ANN) models for biodiesel synthesis from sesame (Sesamum indicum L.) oil under ultrasonication (20 kHz and 1.2 kW) using barium hydroxide as a basic heterogeneous catalyst. RSM based on a five level, four factor central composite design, was employed to obtain the best possible combination of catalyst concentration, methanol to oil molar ratio, temperature and reaction time for maximum FAME content. Experimental data were evaluated by applying RSM integrating with desirability function approach. The importance of each independent variable on the response was investigated by using sensitivity analysis. The optimum conditions were found to be catalyst concentration (1.79 wt%), methanol to oil molar ratio (6.69:1), temperature (31.92°C), and reaction time (40.30 min). For these conditions, experimental FAME content of 98.6% was obtained, which was in reasonable agreement with predicted one. The sensitivity analysis confirmed that catalyst concentration was the main factors affecting the FAME content with the relative importance of 36.93%. The lower values of correlation coefficient (R(2)=0.781), root mean square error (RMSE=4.81), standard error of prediction (SEP=6.03) and relative percent deviation (RPD=4.92) for ANN compared to those R(2) (0.596), RMSE (6.79), SEP (8.54) and RPD (6.48) for RSM proved better prediction capability of ANN in predicting the FAME content.

  12. Nonlinear optical microscopy and ultrasound imaging of human cervical structure

    NASA Astrophysics Data System (ADS)

    Reusch, Lisa M.; Feltovich, Helen; Carlson, Lindsey C.; Hall, Gunnsteinn; Campagnola, Paul J.; Eliceiri, Kevin W.; Hall, Timothy J.

    2013-03-01

    The cervix softens and shortens as its collagen microstructure rearranges in preparation for birth, but premature change may lead to premature birth. The global preterm birth rate has not decreased despite decades of research, likely because cervical microstructure is poorly understood. Our group has developed a multilevel approach to evaluating the human cervix. We are developing quantitative ultrasound (QUS) techniques for noninvasive interrogation of cervical microstructure and corroborating those results with high-resolution images of microstructure from second harmonic generation imaging (SHG) microscopy. We obtain ultrasound measurements from hysterectomy specimens, prepare the tissue for SHG, and stitch together several hundred images to create a comprehensive view of large areas of cervix. The images are analyzed for collagen orientation and alignment with curvelet transform, and registered with QUS data, facilitating multiscale analysis in which the micron-scale SHG images and millimeter-scale ultrasound data interpretation inform each other. This novel combination of modalities allows comprehensive characterization of cervical microstructure in high resolution. Through a detailed comparative study, we demonstrate that SHG imaging both corroborates the quantitative ultrasound measurements and provides further insight. Ultimately, a comprehensive understanding of specific microstructural cervical change in pregnancy should lead to novel approaches to the prevention of preterm birth.

  13. The Application of Ultrasound in 3D Bio-Printing.

    PubMed

    Zhou, Yufeng

    2016-05-05

    Three-dimensional (3D) bioprinting is an emerging and promising technology in tissue engineering to construct tissues and organs for implantation. Alignment of self-assembly cell spheroids that are used as bioink could be very accurate after droplet ejection from bioprinter. Complex and heterogeneous tissue structures could be built using rapid additive manufacture technology and multiple cell lines. Effective vascularization in the engineered tissue samples is critical in any clinical application. In this review paper, the current technologies and processing steps (such as printing, preparation of bioink, cross-linking, tissue fusion and maturation) in 3D bio-printing are introduced, and their specifications are compared with each other. In addition, the application of ultrasound in this novel field is also introduced. Cells experience acoustic radiation force in ultrasound standing wave field (USWF) and then accumulate at the pressure node at low acoustic pressure. Formation of cell spheroids by this method is within minutes with uniform size and homogeneous cell distribution. Neovessel formation from USWF-induced endothelial cell spheroids is significant. Low-intensity ultrasound could enhance the proliferation and differentiation of stem cells. Its use is at low cost and compatible with current bioreactor. In summary, ultrasound application in 3D bio-printing may solve some challenges and enhance the outcomes.

  14. Nonlinear optical microscopy and ultrasound imaging of human cervical structure

    PubMed Central

    Reusch, Lisa M.; Feltovich, Helen; Carlson, Lindsey C.; Hall, Gunnsteinn; Campagnola, Paul J.; Eliceiri, Kevin W.

    2013-01-01

    Abstract. The cervix softens and shortens as its collagen microstructure rearranges in preparation for birth, but premature change may lead to premature birth. The global preterm birth rate has not decreased despite decades of research, likely because cervical microstructure is poorly understood. Our group has developed a multilevel approach to evaluating the human cervix. We are developing quantitative ultrasound (QUS) techniques for noninvasive interrogation of cervical microstructure and corroborating those results with high-resolution images of microstructure from second harmonic generation imaging (SHG) microscopy. We obtain ultrasound measurements from hysterectomy specimens, prepare the tissue for SHG, and stitch together several hundred images to create a comprehensive view of large areas of cervix. The images are analyzed for collagen orientation and alignment with curvelet transform, and registered with QUS data, facilitating multiscale analysis in which the micron-scale SHG images and millimeter-scale ultrasound data interpretation inform each other. This novel combination of modalities allows comprehensive characterization of cervical microstructure in high resolution. Through a detailed comparative study, we demonstrate that SHG imaging both corroborates the quantitative ultrasound measurements and provides further insight. Ultimately, a comprehensive understanding of specific microstructural cervical change in pregnancy should lead to novel approaches to the prevention of preterm birth. PMID:23412434

  15. Temporal Healing in Rat Achilles Tendon: Ultrasound Correlations

    PubMed Central

    Chamberlain, Connie S.; Duenwald-Kuehl, Sarah E.; Okotie, Gregory; Brounts, Sabrina H.; Baer, Geoffrey S.; Vanderby, Ray

    2012-01-01

    The purpose of this study was to explore whether a new ultrasound-based technique correlates with mechanical and biological metrics that describe the tendon healing. Achilles tendons in 32 rats were unilaterally transected and allowed to heal without repair. At 7, 9, 14, or 29 days post-injury, tendons were collected and examined for healing via ultrasound image analysis, mechanical testing, and immunohistochemistry. Consistent with previous studies, we observe that the healing tendons are mechanically inferior (ultimate stress, ultimate load, and normalized stiffness) and biologically altered (cellular and ECM factors) compared to contralateral controls with an incomplete recovery over healing time. Unique to this study, we report: 1) Echo intensity (defined by gray-scale brightness in the ultrasound image) in the healing tissue is related to stress and normalized stiffness. 2) Elongation to failure is relatively constant so that tissue normalized stiffness is linearly correlated with ultimate stress. Together, 1 and 2 suggest a method to quantify mechanical compromise in healing tendons. 3) The amount and type of collagen in healing tendons associates with their strength and normalized stiffness as well as their ultrasound echo intensity. 4) A significant increase of periostin in the healing tissues suggests an important but unexplored role for this ECM protein in tendon healing. PMID:23149902

  16. Underestimation of access flow by ultrasound dilution flow measurements

    NASA Astrophysics Data System (ADS)

    Bos, Clemens; Smits, Johannes H. M.; Zijlstra, Jan J.; Blankestijn, Peter J.; Bakker, Chris J. G.; Viergever, Max A.

    2002-02-01

    For hemodialysis access surveillance, flow measurements are increasingly considered important because they identify accesses at risk of thrombosis. Usually these flow measurements are performed with the ultrasound dilution technique. In a previous patient study it was observed that the resulting flow values were systematically low as compared to magnetic resonance flow measurements, but a satisfactory explanation was lacking. In the present study, we will demonstrate by hemodynamic calculations and in vitro experiments that this discrepancy can be explained by a temporary reduction of the access flow rate, caused by the reversed needle configuration during ultrasound dilution flow measurements. In this configuration, blood is injected retrogressively at one needle and flow between the needles is increased, causing an increased dissipation of energy. The proposed explanation is subsequently confirmed in a patient with a loop graft, by measuring the blood velocity by Doppler ultrasound as a function of reversed dialyzer flow rate. Apart from the ultrasound dilution technique, these findings are applicable to other recently proposed methods for measuring access flow that employ the reversed needle configuration.

  17. Application of ultrasound in bone surgery: two case reports.

    PubMed

    Escoda-Francolí, Jaume; Rodríguez-Rodríguez, Araceli; Berini-Aytés, Leonardo; Gay-Escoda, Cosme

    2010-11-01

    The present study describes some of the applications of ultrasound in bone surgery, based on the presentation of two clinical cases. The Piezosurgery® ultrasound device was used (Tecnología Mectron Medical, Carasco, Italy). In one case the instrument was used to harvest a chin bone graft for placement in a bone defect at level 1.2, while in the other case a bony window osteotomy was made in the external wall of the maxillary sinus, in the context of a sinus membrane lift procedure. The Piezosurgery® device produces specific ultrasound frequency modulation (25-29 kHz), and has been designed to secure increased precision in application to bone surgery. This instrument produces selective sectioning of the mineralized bone structures, and causes less intra- and postoperative bleeding. One of the advantages of the Piezosurgery® device is that it can be used for maxillary sinus lift procedures in dental implant placement. In this context it considerably lessens the risk of sinus mucosa laceration by preparing the bony window in the external wall of the upper maxilla, and can be used to complete the lifting maneuver. The use of ultrasound in application to hard tissues can be regarded as a slow technique compared with the conventional rotary instruments, since it requires special surgical skill and involves a certain learning curve.

  18. Focusing of ferroelectret air-coupled ultrasound transducers

    NASA Astrophysics Data System (ADS)

    Gaal, Mate; Bartusch, Jürgen; Dohse, Elmar; Schadow, Florian; Köppe, Enrico

    2016-02-01

    Air-coupled ultrasound has been applied increasingly as a non-destructive testing method for lightweight construction in recent years. It is particularly appropriate for composite materials being used in automotive and aviation industry. Air-coupled ultrasound transducers mostly consist of piezoelectric materials and matching layers. However, their fabrication is challenging and their signal-to-noise ratio often not sufficient for many testing requirements. To enhance the efficiency, air-coupled ultrasound transducers made of cellular polypropylene have been developed. Because of its small density and sound velocity, this piezoelectric ferroelectret matches the small acoustic impedance of air much better than matching layers applied in conventional transducers. In our contribution, we present two different methods of spherical focusing of ferroelectret transducers for the further enhancement of their performance in NDT applications. Measurements on carbon-fiber-reinforced polymer (CFRP) samples and on metal adhesive joints performed with commercially available focused air-coupled ultrasound transducers are compared to measurements executed with self-developed focused ferroelectret transducers.

  19. Integrating Ultrasound Teaching into Preclinical Problem-based Learning

    PubMed Central

    Tshibwabwa, Eli Tumba; Cannon, Jenifer; Rice, James; Kawooya, Michael G; Sanii, Reza; Mallin, Robert

    2016-01-01

    Objectives: The aim is to provide students in the preclinical with ultrasound image interpretation skills. Research question: Are students in smaller groups with access to a combination of lectures and hands-on patient contact most likely to have better ultrasound image interpretation skills, than students in larger groups with only interactive didactic lectures? Methodology: First-year students at the preclinical Program of the College of Medicine, participated in two 2-h introductory interactive ultrasound sessions. The study comprised two cohorts: 2012/2013 students, who were offered large group teaching (LGT) sessions (control group), and 2013/2014 students, who received the intervention in small group learning problem-based learning (PBL) sessions (experimental group). The overall learning objectives were identical for both groups. The success of the module was evaluated using pre- and post-tests as well as students’ feedback. Results: The students in the experimental group showed significantly higher scores in interpretations of images than those in the control group. The experimental group showed achievement of learning outcomes along with higher levels of satisfaction with the module compared to the latter. Conclusion: Posttest knowledge of the basics of ultrasound improved significantly over the pretest in the experimental group. In addition, students’ overall satisfaction of the ultrasound module was shown to be higher for the PBL compared to the LGT groups. Small groups in an interactive and PBL setting along with opportunities for hands-on practice and simultaneous visualization of findings on a high definition screen should enhance preclinical student learning of the basics of ultrasound. Despite the potential of ultrasound as a clinical, teaching and learning tool for students in the preclinical years, standardized recommendations have yet to be created regarding its integration into the curricula within academic institutions and clinical medicine

  20. Characterization of enzymatically induced degradation of articular cartilage using high frequency ultrasound

    NASA Astrophysics Data System (ADS)

    Töyräs, J.; Rieppo, J.; Nieminen, M. T.; Helminen, H. J.; Jurvelin, J. S.

    1999-11-01

    Ultrasound may provide a quantitative technique for the characterization of cartilage changes typical of early osteoarthrosis. In this study, specific changes in bovine articular cartilage were induced using collagenase and chondroitinase ABC, enzymes that selectively degrade collagen fibril network and digest proteoglycans, respectively. Changes in cartilage structure and properties were quantified using high frequency ultrasound, microscopic analyses and mechanical indentation tests. The ultrasound reflection coefficient of the physiological saline-cartilage interface (R1) decreased significantly (-96.4%, p<0.01) in the collagenase digested cartilage compared to controls. Also a significantly lower ultrasound velocity (-6.2%, p<0.01) was revealed after collagenase digestion. After chondroitinase ABC digestion, a new acoustic interface at the depth of the enzyme penetration front was detected. Cartilage thickness, as determined with ultrasound, showed a high, linear correlation (R = 0.943, n = 60, average difference 0.073 mm (4.0%)) with the thickness measured by the needle-probe method. Both enzymes induced a significant decrease in the Young's modulus of cartilage (p<0.01). Our results indicate that high frequency ultrasound provides a sensitive technique for the analysis of cartilage structure and properties. Possibly ultrasound may be utilized in vivo as a quantitative probe during arthroscopy.

  1. Acoustic structure quantification by using ultrasound Nakagami imaging for assessing liver fibrosis

    PubMed Central

    Tsui, Po-Hsiang; Ho, Ming-Chih; Tai, Dar-In; Lin, Ying-Hsiu; Wang, Chiao-Yin; Ma, Hsiang-Yang

    2016-01-01

    Acoustic structure quantification (ASQ) is a recently developed technique widely used for detecting liver fibrosis. Ultrasound Nakagami parametric imaging based on the Nakagami distribution has been widely used to model echo amplitude distribution for tissue characterization. We explored the feasibility of using ultrasound Nakagami imaging as a model-based ASQ technique for assessing liver fibrosis. Standard ultrasound examinations were performed on 19 healthy volunteers and 91 patients with chronic hepatitis B and C (n = 110). Liver biopsy and ultrasound Nakagami imaging analysis were conducted to compare the METAVIR score and Nakagami parameter. The diagnostic value of ultrasound Nakagami imaging was evaluated using receiver operating characteristic (ROC) curves. The Nakagami parameter obtained through ultrasound Nakagami imaging decreased with an increase in the METAVIR score (p < 0.0001), representing an increase in the extent of pre-Rayleigh statistics for echo amplitude distribution. The area under the ROC curve (AUROC) was 0.88 for the diagnosis of any degree of fibrosis (≥F1), whereas it was 0.84, 0.69, and 0.67 for ≥F2, ≥F3, and ≥F4, respectively. Ultrasound Nakagami imaging is a model-based ASQ technique that can be beneficial for the clinical diagnosis of early liver fibrosis. PMID:27605260

  2. Acoustic structure quantification by using ultrasound Nakagami imaging for assessing liver fibrosis.

    PubMed

    Tsui, Po-Hsiang; Ho, Ming-Chih; Tai, Dar-In; Lin, Ying-Hsiu; Wang, Chiao-Yin; Ma, Hsiang-Yang

    2016-09-08

    Acoustic structure quantification (ASQ) is a recently developed technique widely used for detecting liver fibrosis. Ultrasound Nakagami parametric imaging based on the Nakagami distribution has been widely used to model echo amplitude distribution for tissue characterization. We explored the feasibility of using ultrasound Nakagami imaging as a model-based ASQ technique for assessing liver fibrosis. Standard ultrasound examinations were performed on 19 healthy volunteers and 91 patients with chronic hepatitis B and C (n = 110). Liver biopsy and ultrasound Nakagami imaging analysis were conducted to compare the METAVIR score and Nakagami parameter. The diagnostic value of ultrasound Nakagami imaging was evaluated using receiver operating characteristic (ROC) curves. The Nakagami parameter obtained through ultrasound Nakagami imaging decreased with an increase in the METAVIR score (p < 0.0001), representing an increase in the extent of pre-Rayleigh statistics for echo amplitude distribution. The area under the ROC curve (AUROC) was 0.88 for the diagnosis of any degree of fibrosis (≥F1), whereas it was 0.84, 0.69, and 0.67 for ≥F2, ≥F3, and ≥F4, respectively. Ultrasound Nakagami imaging is a model-based ASQ technique that can be beneficial for the clinical diagnosis of early liver fibrosis.

  3. Ultrasound-induced hyperthermia for the spatio-temporal control of gene expression in bone repair

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher; Padilla, Frédéric; Zhang, Man; Vilaboa, Nuria; Kripfgans, Oliver; Fowlkes, Brian; Franceschi, Renny

    2012-10-01

    Spatial and temporal control over the expression of growth/differentiation factors is of great interest for regeneration of bone, but technologies capable of providing tight and active control over gene expression remain elusive. We propose the use of focused ultrasound for the targeted activation of heat shock-sensitive expression systems in engineered bone. We report in vitro results with cells that express firefly luciferase (fLuc) under the control of a heat shock protein promoter. Cells were embedded in fibrin scaffolds and exposed to focused ultrasound, using a custom 3.3MHz transducer (focal length 4", f-number 1.33", focal dimension 1.2mm lateral FWHM) in CW mode for 2-20 minutes at intensities ISPTA=120-440 W/cm2. The kinetics of ultrasound-mediated activation of the cells was compared with that of strictly thermal activation. Bioluminescence imaging revealed fLuc expression in an area ≥2.5mm in diameter at the position of the ultrasound focus, and the diameter and intensity of the signal increased with the amplitude of the acoustic energy. We also found that ultrasound activated fLuc expression with substantially shorter exposures than thermal activation. Our results demonstrate the potential for focused ultrasound to selectively activate the expression of a gene of interest in an engineered tissue and suggest that focused ultrasound activates the heat shock pathway by a combination of thermal and non-thermal mechanisms.

  4. Controlling collagen fiber microstructure in three-dimensional hydrogels using ultrasound

    PubMed Central

    Garvin, Kelley A.; VanderBurgh, Jacob; Hocking, Denise C.; Dalecki, Diane

    2013-01-01

    Type I collagen is the primary fibrillar component of the extracellular matrix, and functional properties of collagen arise from variations in fiber structure. This study investigated the ability of ultrasound to control collagen microstructure during hydrogel fabrication. Under appropriate conditions, ultrasound exposure of type I collagen during polymerization altered fiber microstructure. Scanning electron microscopy and second-harmonic generation microscopy revealed decreased collagen fiber diameters in response to ultrasound compared to sham-exposed samples. Results of mechanistic investigations were consistent with a thermal mechanism for the effects of ultrasound on collagen fiber structure. To control collagen microstructure site-specifically, a high frequency, 8.3-MHz, ultrasound beam was directed within the center of a large collagen sample producing dense networks of short, thin collagen fibrils within the central core of the gel and longer, thicker fibers outside the beam area. Fibroblasts seeded onto these gels migrated rapidly into small, circularly arranged aggregates only within the beam area, and clustered fibroblasts remodeled the central, ultrasound-exposed collagen fibrils into dense sheets. These investigations demonstrate the capability of ultrasound to spatially pattern various collagen microstructures within an engineered tissue noninvasively, thus enhancing the level of complexity of extracellular matrix microenvironments and cellular functions achievable within three-dimensional engineered tissues. PMID:23927189

  5. A new concept for intraoperative matching of 3D ultrasound and CT.

    PubMed

    Schorr, O; Wörn, H

    2001-01-01

    Matching of ultrasound images with CT or MRI scans is an awkward and unsatisfactory task when using conventional methods. Wide ranging differences in modality of ultrasound and CT/MRI require new techniques to be explored for successful alignment. Ultrasound images characteristically show comparable high noise ratio due to scattering inside the region of interest and the surrounding area. Additionally, shadowing and tissue dependent echo response time produce geometric artifacts. These image distortions are sophisticated to recover. Though image quality and geometric relationship are poor, ultrasound images show the potential for fast, low-cost, non-invasive and flexible image acquisition, predestinated for intraoperative application. The fusion of intraoperative ultrasound and preoperatively acquired CT/MRI images provides both, geometric invariance and flexible fast image acquisition, merging in a powerful tool for augmented three dimensional reality. In this paper we describe a completely new concept for alignment with abstaining from direct rigid or elastic matching of ultrasound to CT/MRI. Instead of placing those images in direct relationship, our approach involves a simulation of ultrasound wave behavior in order to predict B-mode images.

  6. An update around the evidence base for the lower extremity ultrasound regional block technique

    PubMed Central

    Fanelli, Andrea; Ghisi, Daniela; Melotti, Rita Maria

    2016-01-01

    Ultrasound guidance currently represents the gold standard for regional anesthesia. In particular for lower extremity blocks, despite the heterogeneity and the lack of large randomized controlled trials, current literature shows a modest improvement in block onset and quality compared with other localization techniques. This review aims to present the most recent findings on the application of ultrasound guidance for each single lower extremity approach. PMID:26918177

  7. Real time image-based tracking of 4D ultrasound data.

    PubMed

    Øye, Ola Kristoffer; Wein, Wolfgang; Ulvang, Dag Magne; Matre, Knut; Viola, Ivan

    2012-01-01

    We propose a methodology to perform real time image-based tracking on streaming 4D ultrasound data, using image registration to deduce the positioning of each ultrasound frame in a global coordinate system. Our method provides an alternative approach to traditional external tracking devices used for tracking probe movements. We compare the performance of our method against magnetic tracking on phantom and liver data, and show that our method is able to provide results in agreement with magnetic tracking.

  8. A standardized method for 4D ultrasound-guided peripheral nerve blockade and catheter placement.

    PubMed

    Clendenen, N J; Robards, C B; Clendenen, S R

    2014-01-01

    We present a standardized method for using four-dimensional ultrasound (4D US) guidance for peripheral nerve blocks. 4D US allows for needle tracking in multiple planes simultaneously and accurate measurement of the local anesthetic volume surrounding the nerve following injection. Additionally, the morphology and proximity of local anesthetic spread around the target nerve is clearly seen with the described technique. This method provides additional spatial information in real time compared to standard two-dimensional ultrasound.

  9. Phased-array ultrasound technology enhances accuracy of dual frequency ultrasound measurements - towards improved ultrasound bone diagnostics.

    PubMed

    Linder, Hans; Malo, Markus K H; Liukkonen, Jukka; Jurvelin, Jukka S; Töyräs, Juha

    2016-08-01

    Overlying soft tissues attenuate ultrasound backscattered from bone, complicating diagnostics of osteoporosis at the most important fracture sites. Dual-frequency ultrasound technique (DFUS) has been proposed to solve this problem through determination of thickness and composition of overlying soft tissue. This study applies DFUS technique for the first time with a phased-array transducer to investigate if the thickness of two interfering layers (oil and water) can be accurately determined in a variety of configurations. Results indicate that DFUS may be used with phased-array ultrasound systems, making them a suitable combination to consider in future development of clinical in vivo ultrasound methodologies.

  10. [Enhancement of in vitro protoscolicidal effects of high-intensity focused ultrasound by a superabsorbent polymer and ultrasound contrast agent].

    PubMed

    Cai, Hui; Chen, Lu-Lu; Ye, Bin; Zhao, Hai-Long; Liu, Ai-Bo; Zhang, Jing; Zhao, Yi-Feng

    2013-08-01

    This study evaluated whether or not a superabsorbent polymer (SAP) combined with ultrasound contrast agent (UCA) could enhance damage efficacy of high intensity focused ultrasound (HIFU) on Echinococcus granulosus protoscoleces in vitro. Thirty test tubes each with 6 000-7 500 protoscolices were divided into 5 groups: group A (blank control) without HIFU treatment, group B treated with HIFU (50 W) only, group C treated with 10 microl UCA and HIFU, group D treated with 0.01 g SAP and HIFU, group E treated with 10 microl UCA, 0.01 g SAP, and HIFU. In group B, echo enhancement of ultrasound image, suspension temperature (26.0 degrees C +/- 0.2 degrees C) and protoscoleces mortality (30.4%) were higher than that of group A (18.0 degrees C +/- 0.1 degrees C, 1.9%) (P < 0.01). Compared with group B, the echo enhancement of ultrasound image, suspension temperature (27.0 degrees C +/- 0.2 degrees C, 28.2 degrees C +/- 0.2 degrees C) and protoscoleces mortality (50.0%, 53.7%) of groups C and D increased significantly (P < 0.01). In group E, more protoscoleces were stained in red and their internal structures were indistinct. By chi-square test, the protoscoleces mortality of group E (69.7%) was higher than that of groups C and D (P < 0.01). There was no significant difference in suspension temperature among the 3 groups.

  11. A Dual-Modality System for Both Multi-Color Ultrasound-Switchable Fluorescence and Ultrasound Imaging

    PubMed Central

    Kandukuri, Jayanth; Yu, Shuai; Cheng, Bingbing; Bandi, Venugopal; D’Souza, Francis; Nguyen, Kytai T.; Hong, Yi; Yuan, Baohong

    2017-01-01

    Simultaneous imaging of multiple targets (SIMT) in opaque biological tissues is an important goal for molecular imaging in the future. Multi-color fluorescence imaging in deep tissues is a promising technology to reach this goal. In this work, we developed a dual-modality imaging system by combining our recently developed ultrasound-switchable fluorescence (USF) imaging technology with the conventional ultrasound (US) B-mode imaging. This dual-modality system can simultaneously image tissue acoustic structure information and multi-color fluorophores in centimeter-deep tissue with comparable spatial resolutions. To conduct USF imaging on the same plane (i.e., x-z plane) as US imaging, we adopted two 90°-crossed ultrasound transducers with an overlapped focal region, while the US transducer (the third one) was positioned at the center of these two USF transducers. Thus, the axial resolution of USF is close to the lateral resolution, which allows a point-by-point USF scanning on the same plane as the US imaging. Both multi-color USF and ultrasound imaging of a tissue phantom were demonstrated. PMID:28165390

  12. Ultrasound elastography for musculoskeletal applications

    PubMed Central

    Drakonaki, E E; Allen, G M; Wilson, D J

    2012-01-01

    Ultrasound elastography (EUS) is a method to assess the mechanical properties of tissue, by applying stress and detecting tissue displacement using ultrasound. There are several EUS techniques used in clinical practice; strain (compression) EUS is the most common technique that allows real-time visualisation of the elastographic map on the screen. There is increasing evidence that EUS can be used to measure the mechanical properties of musculoskeletal tissue in clinical practice, with the future potential for early diagnosis to both guide and monitor therapy. This review describes the various EUS techniques available for clinical use, presents the published evidence on musculoskeletal applications of EUS and discusses the technical issues, limitations and future perspectives of this method in the assessment of the musculoskeletal system. PMID:23091287

  13. Emergency ultrasound and gallstone ileus.

    PubMed

    Zironi, Gianni; Modolon, Cecilia; Cavazza, Mario

    2007-04-01

    Gallstone ileus is an uncommon cause of mechanical obstruction due to a biliary stone that wedges the intestinal lumen. It is a surgical emergency representing a clinical and diagnostic challenge: the clinical manifestations are rarely specific, often causing diagnostic delay that can adversely affect the prognosis. Emergency ultrasound could be useful in assessing the level and identifying the cause of bowel obstruction. We report a case of a 74-year-old patient with a 6-day history of constipation and crampy abdominal pain without previous history of abdominal diseases. Emergency ultrasound led to an early diagnosis showing dilated small bowel loops with a shadowing mass inside consistent with an ileal stone, in the absence of aberrant located stone on plain abdominal film.

  14. Ultrasound generation from an optical fiber sidewall

    NASA Astrophysics Data System (ADS)

    Zhou, Jingcheng; Wu, Nan; Bi, Siwen; Wang, Xingwei

    2016-04-01

    Ultrasound generation from an optical fiber, based on the photoacoustic principle, could have broad applications, such as ultrasound nondestructive test (NDT) and biomedical ultrasound imaging. There are many advantages of these fiber-optic ultrasonic transducers, such as small size, light weight, ease of use, and immunity to electromagnetic interference. This paper will demonstrate a novel structure which the ultrasound signal is generated on the sidewall of the fiber. Two experimental configurations of the fiber-optic sidewall ultrasonic transducer are discussed. One is that a photoacoustic material is directly coated on the sidewall of the optical fiber. The other one is that the photoacoustic material is directly coated on an aluminum plate and the sidewall fiber is buried in the material. By using this novel sidewall ultrasound generator, we can effectively generate ultrasound signal at multiple, particular locations along one fiber.

  15. [Ultrasound diagnostics of diffuse liver diseases].

    PubMed

    Jung, E M; Wiggermann, P; Stroszczynski, C; Reiser, M F; Clevert, D-A

    2012-08-01

    The current improvements in modern high resolution ultrasound technology, like Tissue Harmonic Imaging (THI), Speckle Reduction Imaging (SRI), partial color coding of B-mode (Color Coded Imaging), and also the advent of ultrasound based elastography as well as contrast-enhanced ultrasound (CEUS) offer fundamentally new ways to characterize diffuse alterations of the liver parenchyma. Besides metabolic disease, disorders of liver fat distribution, infectious and malignant diseases can cause diffuse alterations of the liver parenchyma. In case of liver fibrosis, only a combination of different ultrasound techniques including CEUS, allows the differentiation between benign dysplastic and malignant lesions. Ultrasound elastography allows assessing the extent of the fibrosis. This article focuses on the different ultrasound based diagnostic possibilities in case of diffuse liver disease.

  16. Use of ultrasound in emergency gynaecology.

    PubMed

    Al Wattar, B H; Frank, M; Fage, E; Gupta, P

    2014-02-01

    Ultrasound scan (USS) is an important tool for assessing and diagnosing early pregnancy and gynaecological emergencies. Providing an ultrasound scanning service at all hours would enable and ease prompt diagnosis and appropriate management. It would also help hospitals in reducing costs secondary to unnecessary admissions due to lack of ultrasound out of hours. We have conducted a retrospective observational study that looked into the out of hours admissions to a busy early pregnancy unit in a general district hospital, over a 3-month period. Our results highlight the important role and possible benefits of using ultrasound out of hours and prove it is a cost-effective approach. However, providing ultrasound scanning out of hours is affected by limitations of staff and resources at each unit. This could be avoided by following a multidisciplinary approach in acute services and providing more training for medical staff in ultrasound scanning.

  17. [Ultrasound study before surgery of varicose veins].

    PubMed

    Wuppermann, T; Dittrich, O

    2001-02-01

    Ultrasonographic investigation of the various forms of chronic venous insufficiency has substantial advantages compared to diagnosis with the competing phlebogram, particularly preoperatively. Important details such as side branches in the region of the groin, course variations of the small saphenous vein and insufficiency of the perforators in the lower leg are sometimes missed in the antegrade phlebogram. However, it is absolutely necessary to take these into consideration in order to attain a substained good result of surgery. With adequate qualification of the investigator and using all ultrasound techniques, diagnosis by sonography is better than by means of antegrade phlebogram. There are clear specifications for the documentation. With regard to costs and time required, ultrasonographic investigation of chronic venous insufficiency is superior to the antegrade phlebogram and can be repeated at any time.

  18. Sphericity determination using resonant ultrasound spectroscopy

    DOEpatents

    Dixon, Raymond D.; Migliori, Albert; Visscher, William M.

    1994-01-01

    A method is provided for grading production quantities of spherical objects, such as roller balls for bearings. A resonant ultrasound spectrum (RUS) is generated for each spherical object and a set of degenerate sphere-resonance frequencies is identified. From the degenerate sphere-resonance frequencies and known relationships between degenerate sphere-resonance frequencies and Poisson's ratio, a Poisson's ratio can be determined, along with a "best" spherical diameter, to form spherical parameters for the sphere. From the RUS, fine-structure resonant frequency spectra are identified for each degenerate sphere-resonance frequency previously selected. From each fine-structure spectrum and associated sphere parameter values an asphericity value is determined. The asphericity value can then be compared with predetermined values to provide a measure for accepting or rejecting the sphere.

  19. Sphericity determination using resonant ultrasound spectroscopy

    DOEpatents

    Dixon, R.D.; Migliori, A.; Visscher, W.M.

    1994-10-18

    A method is provided for grading production quantities of spherical objects, such as roller balls for bearings. A resonant ultrasound spectrum (RUS) is generated for each spherical object and a set of degenerate sphere-resonance frequencies is identified. From the degenerate sphere-resonance frequencies and known relationships between degenerate sphere-resonance frequencies and Poisson's ratio, a Poisson's ratio can be determined, along with a 'best' spherical diameter, to form spherical parameters for the sphere. From the RUS, fine-structure resonant frequency spectra are identified for each degenerate sphere-resonance frequency previously selected. From each fine-structure spectrum and associated sphere parameter values an asphericity value is determined. The asphericity value can then be compared with predetermined values to provide a measure for accepting or rejecting the sphere. 14 figs.

  20. Ultrasound findings in cutaneous sarcoidosis

    PubMed Central

    Dybiec, Ewa; Pietrzak, Aldona; Kieszko, Robert; Kanitakis, Jean

    2015-01-01

    The diagnosis of cutaneous sarcoidosis relies mainly on the patient's history, presence of characteristic skin lesions and histological examination that shows a granulomatous, non-necrotizing dermal infiltration. The aim of the study was to assess the ultrasonographic features of cutaneous lesions of sarcoidosis before and after treatment. A 38-year-old woman with systemic sarcoidosis and specific cutaneous lesions was treated with systemic steroids followed by hydroxychloroquine. Ultrasonographic examination of the cutaneous sarcoidosis lesions was performed with a Philips iU 22 and Siemens Acuson S 2000 device, with the use of linear 15 MHz and 17 MHz transducers. Histological examination of skin lesions showed characteristic, naked, non-necrotizing granulomas in the upper dermis. Ultrasound examination revealed well-demarcated, hypoechogenic changes. Power-Doppler scan revealed increased vascularity within the lesions and the surrounding tissue. Clinical improvement of the skin lesions was confirmed by ultrasound examination, which showed a decrease in their size and normalization of dermal echogenicity and vascularity. Ultrasound examination can show cutaneous sarcoidosis lesions and their regression after appropriate treatment. PMID:25821428

  1. Temperature dependency of quantitative ultrasound.

    PubMed

    Pocock, N A; Babichev, A; Culton, N; Graney, K; Rooney, J; Bell, D; Chu, J

    2000-01-01

    Quantitative ultrasound (QUS) parameters are temperature dependent. We examined the effect of temperature on QUS using Lunar Achilles+ and Hologic Sahara units. In vivo studies were performed in a cadaveric foot and in 5 volunteers. QUS scans were performed in the cadaveric foot, using both machines, at temperatures ranging from 15 to 40 degrees C. To assess the effect of change in water bath temperature in the Achilles+, independently of foot temperature, 5 volunteers were studied at water temperatures ranging from 10 to 42 degrees C. In the cadaveric foot there were strong negative correlations between temperature and speed of sound (SOS) but a moderately positive correlation between temperature and broadband ultrasound attenuation (BUA). Stiffness and the Quantitative Ultrasound Index (QUI) in the cadaveric foot showed strong negative correlations with temperature, reflecting their high dependence on SOS. In the 5 volunteers, in whom foot temperature was assumed to be constant, there was a small change in Stiffness in the Achilles+, with variation in water temperature. In conclusion, while there are opposite effects of temperature on SOS and BUA in vivo, there is still a significant effect of temperature variation on Stiffness and the QUI. This may have clinical significance in particular subjects. The precision of QUS may be affected by temperature variation of the environment or of the patient's limb. Instruments utilizing a water bath may be able partly to compensate for changes in environmental temperature, but standardization of water bath temperature is crucial to maximize precision.

  2. Venous catheterization with ultrasound navigation

    SciTech Connect

    Kasatkin, A. A. Nigmatullina, A. R.; Urakov, A. L.

    2015-11-17

    By ultrasound scanning it was determined that respiratory movements made by chest of healthy and sick person are accompanied by respiratory chest rise of internal jugular veins. During the exhalation of an individual diameter of his veins increases and during the breath it decreases down to the complete disappearing if their lumen. Change of the diameter of internal jugular veins in different phases can influence significantly the results of vein puncture and cauterization in patients. The purpose of this research is development of the method increasing the efficiency and safety of cannulation of internal jugular veins by the ultrasound visualization. We suggested the method of catheterization of internal jugular veins by the ultrasound navigation during the execution of which the puncture of venous wall by puncture needle and the following conduction of J-guide is carried out at the moment of patient’s exhalation. This method decreases the risk of complications development during catheterization of internal jugular vein due to exclusion of perforating wound of vein and subjacent tissues and anatomical structures.

  3. Quantitative Ultrasound in Cancer Imaging

    PubMed Central

    Feleppa, Ernest J.; Mamou, Jonathan; Porter, Christopher R.; Machi, Junji

    2010-01-01

    Ultrasound is a relatively inexpensive, portable, and versatile imaging modality that has a broad range of clinical uses. It incorporates many imaging modes, such as conventional gray-scale “B-mode” imaging to display echo amplitude in a scanned plane; M-mode imaging to track motion at a given fixed location over time; duplex, color, and power Doppler imaging to display motion in a scanned plane; harmonic imaging to display non-linear responses to incident ultrasound; elastographic imaging to display relative tissue stiffness; and contrast-agent imaging with simple contrast agents to display blood-filled spaces or with targeted agents to display specific agent-binding tissue types. These imaging modes have been well described in the scientific, engineering, and clinical literature. A less well-known ultrasonic imaging technology is based on quantitative ultrasound or (QUS), which analyzes the distribution of power as a function of frequency in the original received echo signals from tissue and exploits the resulting spectral parameters to characterize and distinguish among tissues. This article discusses the attributes of QUS-based methods for imaging cancers and providing improved means of detecting and assessing tumors. The discussion will include applications to imaging primary prostate cancer and metastatic cancer in lymph nodes to illustrate the methods. PMID:21362522

  4. Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid

    MedlinePlus

    ... Index A-Z Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid An ultrasound-guided thyroid biopsy ... Thyroid? What is Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid? During a fine needle aspiration ...

  5. Ultrasound assessment of transverse carpal ligament thickness: a validity and reliability study.

    PubMed

    Shen, Zhilei Liu; Li, Zong-Ming

    2012-06-01

    The transverse carpal ligament (TCL) forms the palmar boundary of the carpal tunnel and plays an important role in carpal tunnel mechanics. TCL hypertrophy has been observed for individuals with carpal tunnel syndrome (CTS) and postulated as a potential etiologic factor. Ultrasound is particularly advantageous for TCL imaging because of its capability of detecting the interfaces between the TCL and other tissues. The purposes of this study were to develop an ultrasound based method to measure the TCL thickness and to test the validity and reliability of this method. Three operators conducted two sessions of ultrasound examination on eight cadaveric specimens and eight healthy volunteers. A custom script was used to calculate TCL thickness along the TCL length from the ultrasound images. The ultrasound based TCL thickness of the cadaveric specimens was compared with the dissection based TCL thickness for validation. The results showed Pearson's correlation coefficients of 0.867-0.928, intraclass correlation coefficient (ICC) values of 0.726-0.865, a standard error of measurement of 0.02-0.07 mm and a minimal detectable difference of 0.05-0.15 mm. The high correlation coefficients and small errors indicate that the ultrasound based method is valid for measuring TCL thickness. Furthermore, ultrasound measurements showed excellent intraoperator and interoperator reliability with ICC values as 0.826-0.933 and 0.840-0.882, respectively. The ultrasound based TCL thickness was in the range of 0.93-2.34 (1.54 ± 0.33) mm and agreed well with previous studies. The ultrasound method developed in this study is a valuable tool to examine morphologic properties of healthy and pathologic TCLs.

  6. Ultrasound-enhanced ocular delivery of dexamethasone sodium phosphate: an in vivo study

    PubMed Central

    2014-01-01

    Background The eye's unique anatomy and its physiological and anatomical barriers can limit effective drug delivery into the eye. Methods An in vivo study was designed to determine the effectiveness and safety of ultrasound application in enhancing drug delivery in a rabbit model. Permeability of a steroid ophthalmic drug, dexamethasone sodium phosphate, was investigated in ultrasound- and sham-treated cases. For this study, an eye cup filled with dexamethasone sodium phosphate was placed on the cornea. Ultrasound was applied at intensity of 0.8 W/cm2 and frequency of 400 or 600 kHz for 5 min. The drug concentration in aqueous humor samples, collected 90 min after the treatment, was determined using chromatography methods. Light microscopy observations were done to determine the structural changes in the cornea as a result of ultrasound application. Results An increase in drug concentration in aqueous humor samples of 2.8 times (p < 0.05) with ultrasound application at 400 kHz and 2.4 times (p < 0.01) with ultrasound application at 600 kHz was observed as compared to sham-treated samples. Histological analysis showed that the structural changes in the corneas exposed to ultrasound predominantly consisted of minor epithelial disorganization. Conclusions Ultrasound application enhanced the delivery of an anti-inflammatory ocular drug, dexamethasone sodium phosphate, through the cornea in vivo. Ultrasound-enhanced ocular drug delivery appears to be a promising area of research with a potential future application in a clinical setting. PMID:24921047

  7. Preprocedural ultrasound examination versus manual palpation for thoracic epidural catheter insertion

    PubMed Central

    Hasanin, Ahmed M.; Mokhtar, Ali M.; Amin, Shereen M.; Sayed, Ahmed A.

    2017-01-01

    Background and Aims: Ultrasound imaging before neuraxial blocks was reported to improve the ease of insertion and minimize the traumatic trials. However, the data about the use of ultrasound in thoracic epidural block are scanty. In this study, pre-insertion ultrasound scanning was compared to traditional manual palpation technique for insertion of the thoracic epidural catheter in abdominal operations. Subjects and Methods: Forty-eight patients scheduled to midline laparotomy under combined general anesthesia with thoracic epidural analgesia were included in the study. Patients were divided into two groups with regard to technique of epidural catheter insertion; ultrasound group (done ultrasound screening to determine the needle insertion point, angle of insertion, and depth of epidural space) and manual palpation group (used the traditional manual palpation technique). Number of puncture attempts, number of puncture levels, and number of needle redirection attempts were reported. Time of catheter insertion and complications were also reported in both groups. Results: Ultrasound group showed lower number of puncture attempts (1 [1, 1.25] vs. 1.5 [1, 2.75], P = 0.008), puncture levels (1 (1, 1) vs. 1 [1, 2], P = 0.002), and needle redirection attempts (0 [0, 2.25] vs. 3.5 [2, 5], P = 0.00). Ultrasound-guided group showed shorter time for catheter insertion compared to manual palpation group (140 ± 24 s vs. 213 ± 71 s P = 0.00). Conclusion: Preprocedural ultrasound imaging increased the incidence of first pass success in thoracic epidural catheter insertion and reduced the catheter insertion time compared to manual palpation method. PMID:28217056

  8. Ultrasound Imaging of the Musculoskeletal System.

    PubMed

    Cook, Cristi R

    2016-05-01

    Musculoskeletal ultrasound is a rapidly growing field within veterinary medicine. Ultrasound for musculoskeletal disorders has been commonly used in equine and human medicine and is becoming more commonly performed in small animal patients due to the increase in the recognition of soft tissue injuries. Ultrasound is widely available, cost-effective, but technically difficult to learn. Advantages of musculoskeletal ultrasound are the opposite limb is commonly used for comparison to evaluate symmetry of the tendinous structures and the ease of repeat examinations to assess healing. The article discusses the major areas of shoulder, stifle, iliopsoas, gastrocnemius, and musculoskeletal basics.

  9. Application of ultrasound in periodontics: Part I

    PubMed Central

    Bains, Vive K.; Mohan, Ranjana; Bains, Rhythm

    2008-01-01

    Ultrasonic is a branch of acoustics concerned with sound vibrations in frequency ranges above audible level. Ultrasound uses the transmission and reflection of acoustic energy. A pulse is propagated and its reflection is received, both by the transducer. For clinical purposes ultrasound is generated by transducers, which converts electrical energy into ultrasonic waves. This is usually achieved by magnetostriction or piezoelectricity. Primary effects of ultrasound are thermal, mechanical (cavitation and microstreaming), and chemical (sonochemicals). Knowledge of the basic and other secondary effects of ultrasound is essential for the development of techniques of application. PMID:20142941

  10. Pediatric Spinal Ultrasound: Neonatal and Intraoperative Applications.

    PubMed

    Alvarado, Enrique; Leach, James; Caré, Marguerite; Mangano, Francesco; O Hara, Sara

    2017-04-01

    The purpose of this article is to review the use of ultrasound as a screening tool for spinal diseases in neonates and infants and its intraoperative value in selected pediatric neurosurgical disorders. A review of spinal embryology followed by a description of common spinal diseases in neonates assessed with ultrasound is presented. Indications for spinal ultrasound in neonates, commonly identified conditions, and the importance of magnetic resonance imaging in selected cases are emphasized. Additionally, the use of ultrasound in selected neurosurgical spinal diseases in pediatric patients is presented with magnetic resonance imaging and intraoperative correlation. Technique, limitations, and pitfalls are discussed.

  11. Fetal and umbilical Doppler ultrasound in high-risk pregnancies

    PubMed Central

    Alfirevic, Zarko; Stampalija, Tamara; Gyte, Gillian ML

    2014-01-01

    Background Abnormal blood flow patterns in fetal circulation detected by Doppler ultrasound may indicate poor fetal prognosis. It is also possible false positive Doppler ultrasound findings could encourage inappropriate early delivery. Objectives The objective of this review was to assess the effects of Doppler ultrasound used to assess fetal well-being in high-risk pregnancies on obstetric care and fetal outcomes. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (September 2009) and the reference lists of identified studies. Selection criteria Randomised and quasi-randomised controlled trials of Doppler ultrasound for the investigation of umbilical and fetal vessels waveforms in high-risk pregnancies compared to no Doppler ultrasound. Data collection and analysis Two authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. Data entry was checked. Main results Eighteen completed studies involving just over 10,000 women were included. The trials were generally of unclear quality with some evidence of possible publication bias. The use of Doppler ultrasound in high-risk pregnancy was associated a reduction in perinatal deaths (risk ratio (RR) 0.71, 95% confidence interval (CI) 0.52 to 0.98, 16 studies, 10,225 babies, 1.2% versus 1.7 %, numbers needed to treat = 203; 95%CI 103 to 4352). There were also fewer inductions of labour (average RR 0.89, 95% CI 0.80 to 0.99, 10 studies, 5633 women, random effects) and fewer caesarean sections (RR 0.90, 95% CI 0.84 to 0.97, 14 studies, 7918 women). No difference was found in operative vaginal births (RR 0.95, 95% CI 0.80 to 1.14, four studies, 2813 women) nor in Apgar scores less than seven at five minutes (RR 0.92, 95% CI 0.69 to 1.24, seven studies, 6321 babies). Authors’ conclusions Current evidence suggests that the use of Doppler ultrasound in high-risk pregnancies reduced the risk of perinatal deaths and resulted in less

  12. Numerical simulations of clinical focused ultrasound functional neurosurgery

    PubMed Central

    Pulkkinen, Aki; Werner, Beat; Martin, Ernst; Hynynen, Kullervo

    2014-01-01

    A computational model utilizing grid and finite difference methods was developed to simulate focused ultrasound functional neurosurgery interventions. The model couples the propagation of ultrasound in fluids (soft tissues) and solids (skull) with acoustic and visco-elastic wave equations. The computational model was applied to simulate clinical focused ultrasound functional neurosurgery treatments performed in patients suffering from therapy resistant chronic neuropathic pain. Datasets of five patients were used to derive the treatment geometry. Eight sonications performed in the treatments were then simulated with the developed model. Computations were performed by driving the simulated phased array ultrasound transducer with the acoustic parameters used in the treatments. Resulting focal temperatures and size of the thermal foci were compared quantitatively, in addition to qualitative inspection of the simulated pressure and temperature fields. This study found that the computational model and the simulation parameters predicted an average of 24 ± 13 % lower focal temperature elevations than observed in the treatments. The size of the simulated thermal focus was found to be 40 ± 13 % smaller in the anterior–posterior direction and 22 ± 14% smaller in the inferior–superior direction than in the treatments. The location of the simulated thermal focus was off from the prescribed target by 0.3 ± 0.1 mm, while the peak focal temperature elevation observed in the measurements was off by 1.6 ± 0.6 mm. Although the results of the simulations suggest that there could be some inaccuracies in either the tissue parameters used, or in the simulation methods, the simulations were able to predict the focal spot locations and temperature elevations adequately for initial treatment planning performed to assess, for example, the feasibility of sonication. The accuracy of the simulations could be improved if more precise ultrasound tissue properties (especially of the

  13. An Assessment of Iterative Reconstruction Methods for Sparse Ultrasound Imaging

    PubMed Central

    Valente, Solivan A.; Zibetti, Marcelo V. W.; Pipa, Daniel R.; Maia, Joaquim M.; Schneider, Fabio K.

    2017-01-01

    Ultrasonic image reconstruction using inverse problems has recently appeared as an alternative to enhance ultrasound imaging over beamforming methods. This approach depends on the accuracy of the acquisition model used to represent transducers, reflectivity, and medium physics. Iterative methods, well known in general sparse signal reconstruction, are also suited for imaging. In this paper, a discrete acquisition model is assessed by solving a linear system of equations by an ℓ1-regularized least-squares minimization, where the solution sparsity may be adjusted as desired. The paper surveys 11 variants of four well-known algorithms for sparse reconstruction, and assesses their optimization parameters with the goal of finding the best approach for iterative ultrasound imaging. The strategy for the model evaluation consists of using two distinct datasets. We first generate data from a synthetic phantom that mimics real targets inside a professional ultrasound phantom device. This dataset is contaminated with Gaussian noise with an estimated SNR, and all methods are assessed by their resulting images and performances. The model and methods are then assessed with real data collected by a research ultrasound platform when scanning the same phantom device, and results are compared with beamforming. A distinct real dataset is finally used to further validate the proposed modeling. Although high computational effort is required by iterative methods, results show that the discrete model may lead to images closer to ground-truth than traditional beamforming. However, computing capabilities of current platforms need to evolve before frame rates currently delivered by ultrasound equipments are achievable. PMID:28282862

  14. Numerical simulations of clinical focused ultrasound functional neurosurgery

    NASA Astrophysics Data System (ADS)

    Pulkkinen, Aki; Werner, Beat; Martin, Ernst; Hynynen, Kullervo

    2014-04-01

    A computational model utilizing grid and finite difference methods were developed to simulate focused ultrasound functional neurosurgery interventions. The model couples the propagation of ultrasound in fluids (soft tissues) and solids (skull) with acoustic and visco-elastic wave equations. The computational model was applied to simulate clinical focused ultrasound functional neurosurgery treatments performed in patients suffering from therapy resistant chronic neuropathic pain. Datasets of five patients were used to derive the treatment geometry. Eight sonications performed in the treatments were then simulated with the developed model. Computations were performed by driving the simulated phased array ultrasound transducer with the acoustic parameters used in the treatments. Resulting focal temperatures and size of the thermal foci were compared quantitatively, in addition to qualitative inspection of the simulated pressure and temperature fields. This study found that the computational model and the simulation parameters predicted an average of 24 ± 13% lower focal temperature elevations than observed in the treatments. The size of the simulated thermal focus was found to be 40 ± 13% smaller in the anterior-posterior direction and 22 ± 14% smaller in the inferior-superior direction than in the treatments. The location of the simulated thermal focus was off from the prescribed target by 0.3 ± 0.1 mm, while the peak focal temperature elevation observed in the measurements was off by 1.6 ± 0.6 mm. Although the results of the simulations suggest that there could be some inaccuracies in either the tissue parameters used, or in the simulation methods, the simulations were able to predict the focal spot locations and temperature elevations adequately for initial treatment planning performed to assess, for example, the feasibility of sonication. The accuracy of the simulations could be improved if more precise ultrasound tissue properties (especially of the

  15. Geometric Evaluation of Systematic Transrectal Ultrasound Guided Prostate Biopsy

    PubMed Central

    Han, Misop; Chang, Doyoung; Kim, Chunwoo; Lee, Brian J.; Zuo, Yihe; Kim, Hyung-Joo; Petrisor, Doru; Trock, Bruce; Partin, Alan W.; Rodriguez, Ronald; Carter, H. Ballentine; Allaf, Mohamad; Kim, Jongwon; Stoianovici, Dan

    2013-01-01

    Purpose Transrectal ultrasound guided prostate biopsy results rely on physician ability to target the gland according to the biopsy schema. However, to our knowledge it is unknown how accurately the freehand, transrectal ultrasound guided biopsy cores are placed in the prostate and how the geometric distribution of biopsy cores may affect the prostate cancer detection rate. Materials and Methods To determine the geometric distribution of cores, we developed a biopsy simulation system with pelvic mock-ups and an optical tracking system. Mock-ups were biopsied in a freehand manner by 5 urologists and by our transrectal ultrasound robot, which can support and move the transrectal ultrasound probe. We compared 1) targeting errors, 2) the accuracy and precision of repeat biopsies, and 3) the estimated significant prostate cancer (0.5 cm3 or greater) detection rate using a probability based model. Results Urologists biopsied cores in clustered patterns and under sampled a significant portion of the prostate. The robot closely followed the predefined biopsy schema. The mean targeting error of the urologists and the robot was 9.0 and 1.0 mm, respectively. Robotic assistance significantly decreased repeat biopsy errors with improved accuracy and precision. The mean significant prostate cancer detection rate of the urologists and the robot was 36% and 43%, respectively (p <0.0001). Conclusions Systematic biopsy with freehand transrectal ultrasound guidance does not closely follow the sextant schema and may result in suboptimal sampling and cancer detection. Repeat freehand biopsy of the same target is challenging. Robotic assistance with optimized biopsy schemas can potentially improve targeting, precision and accuracy. A clinical trial is needed to confirm the additional benefits of robotic assistance. PMID:23088974

  16. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    SciTech Connect

    Morimoto, A.K.; Bow, W.J.; Strong, D.S.

    1995-06-01

    The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.

  17. Propofol use in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound

    PubMed Central

    Cheriyan, Danny G; Byrne, Michael F

    2014-01-01

    Compared to standard endoscopy, endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are often lengthier and more complex, thus requiring higher doses of sedatives for patient comfort and compliance. The aim of this review is to provide the reader with information regarding the use, safety profile, and merits of propofol for sedation in advanced endoscopic procedures like ERCP and EUS, based on the current literature. PMID:24833847

  18. A facile synthesis of deuteroporphyrins derivatives under ultrasound irradiation.

    PubMed

    Hu, Bingcheng; Zhou, Weiyou; Tang, Ying; Huang, Chengmei; Liu, Zuliang

    2010-02-01

    A facile, efficient and general method for preparing deuteroporphyrin derivatives by using concentrated H(2)SO(4) and alcohol under ultrasound irradiation has been developed. A series of new deuteroporphyrin derivatives bearing different propionic ester groups have been synthesized in good yields starting from readily accessible deuterohemin. The characterization of these compounds confirms the synthetic methodology. Compared with conventional methods, the main advantages of the present procedure are shorter reaction time and higher yields.

  19. Fetal Neurosonogaphy: Ultrasound and Magnetic Resonance Imaging in Competition.

    PubMed

    Tercanli, S; Prüfer, F

    2016-12-01

    superior to the MRI findings.Another study appearing in this issue study of CNS anomalies in fetuses with complex clubfoot also showed additionally diagnosed CNS anomalies in 4 cases on MRI. MRI yielded supplementary findings that were not visible on ultrasound in 6 cases. Although the number of cases is small, it was able to be shown, as in other studies, that a certain percentage of CNS anomalies is able to be evaluated on an additional or supplementary basis on MRI.Since intrauterine MRI has been becoming increasingly important in recent years, it is necessary to determine when MRI is indicated. There is general consensus in the literature that MRI is not a screening method for detecting fetal anomalies but should be viewed as a supplementary method to ultrasound 8 9 10. However, MRI application in pregnancy is increasing. Intrauterine MRI is most commonly used in the case of abnormal ultrasound findings regarding the CNS 11 12 13. This includes morphological evaluation of malformations and recently also of acquired hypoxic-ischemic diseases, bleeding and inflammation such as CMV infections. Thoracic and abdominal malformations are also indications for MRI for the evaluation of the lung volume in diaphragmatic defects and in the case of suspicion of esophageal atresia abnormal placentation. Further possible indications for the use of MRI include monochorial multiple pregnancies with a feto-fetal transfusion syndrome (for the evaluation of neurological development) and select cases with known diseases and syndromes 14. The majority of studies for comparing intrauterine MRI to sonographic diagnosis include a small number of cases with limited or no follow-up. Data regarding sensitivities, specificities, and positive predictive values is limited. Many studies simply calculate the difference in percentages on the basis of a small number of cases. The best available data is in regard to CNS anomalies. In one of the few meta-analyses including 34 studies and documented

  20. A Tissue-Mimicking Ultrasound Test Object Using Droplet Vaporization to Create Point Targets

    PubMed Central

    Carneal, Catherine M.; Kripfgans, Oliver D.; Krücker, Jochen; Carson, Paul L.; Fowlkes, J. Brian

    2012-01-01

    Ultrasound test objects containing reference point targets could be useful for evaluating ultrasound systems and phase aberration correction methods. Polyacrylamide gels containing albumin-stabilized droplets (3.6 µm mean diameter) of dodecafluoropentane (DDFP) are being developed for this purpose. Perturbation by ultrasound causes spontaneous vaporization of the superheated droplets to form gas bubbles, a process termed acoustic droplet vaporization (ADV). The resulting bubbles (20 to 160 µm diameter) are small compared with acoustic wavelengths in diagnostic ultrasound and are theoretically suitable for use as point targets (phase errors <20° for typical f-numbers). Bubbles distributed throughout the material are convenient for determining the point spread function in an imaging plane or volume. Cooling the gel causes condensation of the DDFP droplets, which may be useful for storage. Studying ADV in such viscoelastic media could provide insight into potential bioeffects from rapid bubble formation. PMID:21937339

  1. Efficacy of ultrasound-guided thoracentesis catheter drainage for pleural effusion

    PubMed Central

    Cao, Weitian; Wang, Yi; Zhou, Ningming; Xu, Bing

    2016-01-01

    The factors influencing the efficacy of ultrasound-guided thoracentesis catheter drainage were investigated in the present study. A retrospective analysis of clinical data from 435 patients who presented with a pleural effusion was performed. Patients were divided into a control group and an intervention group. Thirty-seven patients in the control group were given standard care using pleural puncture to draw the excess fluid. The 398 patients in the intervention group were treated using ultrasound-guided thoracentesis catheter drainage. The rate of successful drainage of a pleural effusion was significantly higher (P<0.05), while the rate of complication was lower, in the ultrasound-guided thoracentesis cases compared to standard care treatment. In conclusion, ultrasound-guided thoracentesis catheter drainage is an efficient, safe and minimally invasive procedure to alleviate pleural effusion. The efficacy of the procedure is related to the separation of pleural effusion, drainage tube type and tube diameter. PMID:28105155

  2. Tubular Enhanced Geodesic Active Contours for Continuum Robot Detection using 3D Ultrasound.

    PubMed

    Ren, Hongliang; Dupont, Pierre E

    2012-01-01

    Three dimensional ultrasound is a promising imaging modality for minimally invasive robotic surgery. As the robots are typically metallic, they interact strongly with the sound waves in ways that are not modeled by the ultrasound system's signal processing algorithms. Consequently, they produce substantial imaging artifacts that can make image guidance difficult, even for experienced surgeons. This paper introduces a new approach for detecting curved continuum robots in 3D ultrasound images. The proposed approach combines geodesic active contours with a speed function that is based on enhancing the "tubularity" of the continuum robot. In particular, it takes advantage of the known robot diameter along its length. It also takes advantage of the fact that the robot surface facing the ultrasound probe provides the most accurate image. This method, termed Tubular Enhanced Geodesic Active Contours (TEGAC), is demonstrated through ex vivo intracardiac experiments to offer superior performance compared to conventional active contours.

  3. Dual Flat Flextensional Ultrasound Transducers for Enhancement of Transdermal Drug Delivery

    NASA Astrophysics Data System (ADS)

    Zhang, Hong-Ye; Yeo, Swee-Hock

    2004-09-01

    The development of a lightweight, simple-structure and low-power-consumption sonophoresis device for drug delivery is required. For this purpose, a new sonophoresis device with dual flat flextensional ultrasound transducers was fabricated and investigated in this work. When both ultrasound transducers were operated at their fundamental resonance frequency (26.83 kHz), the radiated acoustic intensity (Isptp) was about 2 to 4 times higher than that generated by a single ultrasound transducer in the proposed device. The proposed sonophoresis device has the capability to reduce the applied voltage at least twofold. Compared to the ultrasonic probe or converter from a commercial sonicator that weighs about one kilogram, the proposed sonophoresis device with double ultrasound transducers weighs only 73.3 g. All the results showed that the proposed sonophoresis device is feasible for use in practical applications.

  4. Spatial and frequency-based super-resolution of ultrasound images.

    PubMed

    Wu, Mon-Ju; Karls, Joseph; Duenwald-Kuehl, Sarah; Vanderby, Ray; Sethares, William

    2014-07-01

    Modern ultrasound systems can output video images containing more spatial and temporal information than still images. Super-resolution techniques can exploit additional information but face two challenges: image registration and complex motion. In addition, information from multiple available frequencies is unexploited. Herein, we utilised these information sources to create better ultrasound images and videos, extending existing technologies for image capture. Spatial and frequency-based super-resolution processing using multiple motion estimation and frequency combination was applied to ultrasound videos of deforming models. Processed images are larger, have greater clarity and detail, and less variability in intensity between frames. Significantly, strain measurements are more accurate and precise than those from raw videos, and have a higher contrast ratio between 'tumour' and 'surrounding tissue' in a phantom model. We attribute improvements to reduced noise and increased resolution in processed images. Our methods can significantly improve quantitative and qualitative assessments of ultrasound images when compared assessments of standard images.

  5. Ultrasound assisted combustion synthesis of TiC in Al-Ti-C system.

    PubMed

    Liu, Zhiwei; Rakita, Milan; Xu, Wilson; Wang, Xiaoming; Han, Qingyou

    2015-11-01

    This research investigated the effects of high-intensity ultrasound on the combustion synthesis of TiC particles in Al-Ti-C system. The process involved that high-intensity ultrasound was applied on the surface of a compacted Al-Ti-C pellet directly through a Nb probe during the thermal explosion reaction. By comparing with the sample without ultrasonic treatment, it was found that the thermal explosion reaction for synthesizing TiC phase could take place thoroughly in the ultrasonically treated sample. During the process of synthesizing TiC phase, the dissolution of solid graphite particles into the Al-Ti melt, as well as the nucleation and growth of TiC particles could be promoted effectively due to the effects of ultrasound, leading to an enhancement of the formation of TiC particles. Ultrasound assisted combustion synthesis as a simple and effective approach was proposed for synthesizing materials in this research.

  6. Ultrasound assisted enzymatic pre-treatment of high fat content dairy wastewater.

    PubMed

    Adulkar, Tejal V; Rathod, Virendra K

    2014-05-01

    This paper illustrates the application of ultrasound in a dairy waste water treatment for the removal of fat using enzyme as a catalyst. Lipase Z was used to perform the enzymatic pre-hydrolysis of a synthetic dairy wastewater containing around 2000 mg/L of fat content coupled with ultrasound irradiation. Different process parameters like effect of enzyme loading, temperature, ultrasound power, frequency, duty cycle and speed of agitation are optimized. The maximum hydrolysis of 78% is achieved at 0.2% enzyme loading (w/v), 30°C temperature, 165 W of ultrasonication power at 25 kHz and 66% duty cycle. It was observed that the enzymatic pre-hydrolysis under the influence of ultrasound drastically reduces the reaction time from 24h to 40 min as compared to conventional stirring with improved yield.

  7. Internal Jugular Vein Cannulation: An Ultrasound-Guided Technique Versus a Landmark-Guided Technique

    PubMed Central

    Turker, Gurkan; Kaya, Fatma Nur; Gurbet, Alp; Aksu, Hale; Erdogan, Cuneyt; Atlas, Ahmet

    2009-01-01

    OBJECTIVES To compare the landmark-guided technique versus the ultrasound-guided technique for internal jugular vein cannulation in spontaneously breathing patients. METHODS A total of 380 patients who required internal jugular vein cannulation were randomly assigned to receive internal jugular vein cannulation using either the landmark- or ultrasound-guided technique in Bursa, Uludag University Faculty of Medicine, between April and November, 2008. Failed catheter placement, risk of complications from placement, risk of failure on first attempt at placement, number of attempts until successful catheterization, time to successful catheterization and the demographics of each patient were recorded. RESULTS The overall complication rate was higher in the landmark group than in the ultrasound-guided group (p < 0.01). Carotid puncture rate and hematoma were more frequent in the landmark group than in the ultrasound-guided group (p < 0.05). The number of attempts for successful placement was significantly higher in the landmark group than in the ultrasound-guided group, which was accompanied by a significantly increased access time observed in the landmark group (p < 0.05 and p < 0.01, respectively). Although there were a higher number of attempts, longer access time, and a more frequent complication rate in the landmark group, the success rate was found to be comparable between the two groups. CONCLUSION The findings of this study indicate that internal jugular vein catheterization guided by real-time ultrasound results in a lower access time and a lower rate of immediate complications. PMID:19841706

  8. Venous elastography: validation of a novel high-resolution ultrasound method for measuring vein compliance using finite element analysis.

    PubMed

    Biswas, Rohan; Patel, Prashant; Park, Dae W; Cichonski, Thomas J; Richards, Michael S; Rubin, Jonathan M; Hamilton, James; Weitzel, William F

    2010-01-01

    Ultrasonography for the noninvasive assessment of tissue properties has enjoyed widespread success. With the growing emphasis in recent years on arteriovenous fistulae (AVFs) for dialysis vascular access in patients with end-stage renal disease, and on reducing AVF failures, there is increasing interest in ultrasound for the preoperative evaluation of the mechanical and elastic properties of arteries and veins. This study used high-resolution ultrasound with phase-sensitive speckle tracking to obtain in vivo vein elasticity measurements during dilation. The results of this novel ultrasound technique were then compared to a computer model of venous strain. The computer model and ultrasound analysis of the vessel wall demonstrated internally consistent positive and negative longitudinal strain values as the vein wall underwent dilation. These results support further investigation of the use of phase-sensitive speckle tracking for ultrasound venous mapping for preoperative vascular access evaluation.

  9. In Vivo Application and Localization of Transcranial Focused Ultrasound Using Dual-Mode Ultrasound Arrays

    PubMed Central

    Haritonova, Alyona; Liu, Dalong; Ebbini, Emad S.

    2015-01-01

    Focused ultrasound (FUS) has been proposed for a variety of transcranial applications, including neuromodulation, tumor ablation, and blood brain barrier opening. A flurry of activity in recent years has generated encouraging results demonstrating its feasibility in these and other applications. To date, monitoring of FUS beams have been primarily accomplished using MR guidance, where both MR thermography and elastography have been used. The recent introduction of real-time dual-mode ultrasound array (DMUA) systems offers a new paradigm in transcranial focusing. In this paper, we present first experimental results of ultrasound-guided transcranial FUS (tFUS) application in a rodent brain, both ex vivo and in vivo. DMUA imaging is used for visualization of the treatment region for placement of the focal spot within the brain. This includes the detection and localization of pulsating blood vessels at or near the target point(s). In addition, DMUA imaging is used to monitor and localize the FUS-tissue interactions in real-time. In particular, a concave (40-mm radius of curvature), 32-element, 3.5 MHz DMUA prototype was used for imaging and tFUS application in ex vivo and in vivo rat model. The ex vivo experiments were used to evaluate the point spread function (psf) of the transcranial DMUA imaging at various points within the brain. In addition, DMUA-based transcranial ultrasound thermography measurements were compared with thermocouple measurements of subtherapeutic tFUS heating in rat brain ex vivo. The ex vivo setting was also used to demonstrate the DMUA capability to produce localized thermal lesions. The in vivo experiments were designed to demonstrate the ability of the DMUA to apply, monitor, and localize subtherapeutic tFUS patterns that could be beneficial in transient blood brain barrier opening. The results show that, while the DMUA focus is degraded due to the propagation through the skull, it still produces localized heating effects within sub

  10. Hot topics in biomedical ultrasound: ultrasound therapy and its integration with ultrasonic imaging

    NASA Astrophysics Data System (ADS)

    Everbach, E. Carr

    2005-09-01

    Since the development of biomedical ultrasound imaging from sonar after WWII, there has been a clear divide between ultrasonic imaging and ultrasound therapy. While imaging techniques are designed to cause as little change as possible in the tissues through which ultrasound propagates, ultrasound therapy typically relies upon heating or acoustic cavitation to produce a desirable therapeutic effect. Concerns over the increasingly high acoustic outputs of diagnostic ultrasound scanners prompted the adoption of the Mechanical Index (MI) and Thermal Index (TI) in the early 1990s. Therapeutic applications of ultrasound, meanwhile, have evolved from deep tissue heating in sports medicine to include targeted drug delivery, tumor and plaque ablation, cauterization via high intensity focused ultrasound (HIFU), and accelerated dissolution of blood clots. The integration of ultrasonic imaging and therapy in one device is just beginning, but the promise of improved patient outcomes is balanced by regulatory and practical impediments.

  11. Evaluation of two-dimensional and three-dimensional ultrasound in the assessment of thyroid volume of the Indo-Pacific bottlenose dolphin (Tursiops aduncus).

    PubMed

    Kot, Brian C W; Ying, Michael T C; Brook, Fiona M; Kinoshita, Reimi E

    2012-03-01

    The assessment of thyroid volume plays an indispensable role in the diagnosis and management of different thyroid diseases. The present study evaluates the accuracy of dolphin thyroid volume measurement as determined by four two-dimensional (2D) ultrasound methods (A-D), with a standard of reference using three-dimensional (3D) ultrasound. The measurement accuracy for different recognized thyroid configuration is also evaluated. Inter- and intraoperator variability of the measurement methods was determined. Thyroid ultrasound examinations were conducted in 16 apparently healthy Indo-Pacific bottlenose dolphins (Tursiops aduncus) with 2D and 3D ultrasound under identical scanning conditions. All 2D ultrasound measurement methods yielded high accuracies (79.9-81.3%) when compared with the 3D ultrasound measurement, and had high measurement reproducibility (77.6-86.2%) and repeatability (78.1-99.7%). For 2D ultrasound measurements, Methods A and B were more accurate and reliable than Methods C and D, regardless of thyroid configuration. Ultrasound is useful in the measurement of thyroid volume in bottlenose dolphins. For the first time, a reliable ultrasound scanning protocol for measuring dolphin thyroid volume was developed, which provides a means to establish a normative reference for the diagnosis of thyroid pathologies and to monitor the thyroid volume during the course of treatment in living dolphins. Key words: 3D ultrasound, Indo-Pacific bottlenose dolphin, thyroid volume measurement, Tursiops aduncus.

  12. Improvement of ultrasound speckle image velocimetry using image enhancement techniques.

    PubMed

    Yeom, Eunseop; Nam, Kweon-Ho; Paeng, Dong-Guk; Lee, Sang Joon

    2014-01-01

    Ultrasound-based techniques have been developed and widely used in noninvasive measurement of blood velocity. Speckle image velocimetry (SIV), which applies a cross-correlation algorithm to consecutive B-mode images of blood flow has often been employed owing to its better spatial resolution compared with conventional Doppler-based measurement techniques. The SIV technique utilizes speckles backscattered from red blood cell (RBC) aggregates as flow tracers. Hence, the intensity and size of such speckles are highly dependent on hemodynamic conditions. The grayscale intensity of speckle images varies along the radial direction of blood vessels because of the shear rate dependence of RBC aggregation. This inhomogeneous distribution of echo speckles decreases the signal-to-noise ratio (SNR) of a cross-correlation analysis and produces spurious results. In the present study, image-enhancement techniques such as contrast-limited adaptive histogram equalization (CLAHE), min/max technique, and subtraction of background image (SB) method were applied to speckle images to achieve a more accurate SIV measurement. A mechanical sector ultrasound scanner was used to obtain ultrasound speckle images from rat blood under steady and pulsatile flows. The effects of the image-enhancement techniques on SIV analysis were evaluated by comparing image intensities, velocities, and cross-correlation maps. The velocity profiles and wall shear rate (WSR) obtained from RBC suspension images were compared with the analytical solution for validation. In addition, the image-enhancement techniques were applied to in vivo measurement of blood flow in human vein. The experimental results of both in vitro and in vivo SIV measurements show that the intensity gradient in heterogeneous speckles has substantial influence on the cross-correlation analysis. The image-enhancement techniques used in this study can minimize errors encountered in ultrasound SIV measurement in which RBCs are used as flow

  13. High-frequency ultrasound detection of cell death: Spectral differentiation of different forms of cell death in vitro

    PubMed Central

    Pasternak, Maurice M.; Sadeghi-Naini, Ali; Ranieri, Shawn M.; Giles, Anoja; Oelze, Michael L.; Kolios, Michael C.; Czarnota, Gregory J.

    2016-01-01

    High frequency quantitative ultrasound techniques were investigated to characterize different forms of cell death in vitro. Suspension-grown acute myeloid leukemia cells were treated to cause apoptosis, oncosis, mitotic arrest, and heat-induced death. Samples were scanned with 20 and 40 MHz ultrasound and assessed histologically in terms of cellular structure. Frequency-domain analysis of 20 MHz ultrasound data demonstrated midband fit changes of 6.0 ± 0.7 dBr, 6.2 ± 1.8 dBr, 4.0 ± 1.0 dBr and −4.6 ± 1.7 dBr after 48-hour cisplatinum-induced apoptosis, 48-hour oncotic decay, 36-hour colchicine-induced mitotic arrest, and heat treatment compared to control, respectively. Trends from 40 MHz ultrasound were similar. Spectral slope changes obtained from 40 MHz ultrasound data were reflective of alterations in cell and nucleus size. Chromatin pyknosis or lysis trends suggested that the density of nuclear material may be responsible for observed changes in ultrasound backscatter. Flow cytometry analysis confirmed the modes of cell death and supported midband fit trends in ultrasound data. Scatterer-size and concentration estimates obtained from a fluid-filled sphere form factor model further corresponded with spectral analysis and histology. Results indicate quantitative ultrasound spectral analysis may be used for probing anti-cancer response and distinguishing various modes of cell death in vitro. PMID:28050578

  14. Thermal Field Imaging Using Ultrasound

    NASA Technical Reports Server (NTRS)

    Andereck, D.; Rahal, S.; Fife, S.

    2000-01-01

    It is often desirable to be able to determine the temperature field in the interiors of opaque fluids forced into convection by externally imposed temperature gradients. To measure the temperature at a point in an opaque fluid in the usual fashion requires insertion of a probe, and to determine the full field therefore requires either the ability to move this probe or the introduction of multiple probes. Neither of these solutions is particularly satisfactory, although they can lead to quite accurate measurements. As an alternative we have investigated the use of ultrasound as a relatively non-intrusive probe of the temperature field in convecting opaque fluids. The temperature dependence of the sound velocity can be sufficiently great to permit a determination of the temperature from timing the traversal of an ultrasound pulse across a chamber. In this paper we will present our results on convecting flows of transparent and opaque fluids. Our experimental cells consist of relatively narrow rectangular cavities made of thermally insulating materials on the sides, and metal top and bottom plates. The ultrasound transducer is powered by a pulser/receiver, the signal output of which goes to a very high speed signal averager. The average of several hundred to several thousand signals is then sent to a computer for storage and analysis. The experimental procedure is to establish a convective flow by imposing a vertical temperature gradient on the chamber, and then to measure, at several regularly spaced locations, the transit time for an ultrasound pulse to traverse the chamber horizontally (parallel to the convecting rolls) and return to the transducer. The transit time is related to the temperature of the fluid through which the sound pulse travels. Knowing the relationship between transit time and temperature (determined in a separate experiment), we can extract the average temperature across the chamber at that location. By changing the location of the transducer it

  15. Effects of ultrasound on oily sludge deoiling.

    PubMed

    Xu, Ning; Wang, Wenxiang; Han, Pingfang; Lu, Xiaoping

    2009-11-15

    Oily sludge with an initial oil content of 0.130 g g(-1) (dry basis) was mixed with water and treated in an ultrasound cleaning tank. The oil was then separated from the oily sludge by air floatation. Experiments were carried out with and without 28 kHz ultrasonic irradiation at different temperatures. The results show that the minimum oil content, 0.055 g g(-1) (dry basis), was obtained at 40 degrees C after ultrasound irradiation, which was 55.6% less than without ultrasonic irradiation. In addition, this work clearly establishes that 28 kHz ultrasound is superior to 40 kHz ultrasound. The ultrasonic acoustic pressure amplitude with the 28kHz ultrasound was 0.085 MPa; the 28 kHz ultrasound also exhibited lower oil content than the 40 kHz ultrasound, which yielded 0.120 MPa acoustic pressure amplitude. It can also be concluded that sodium silicate obstructs ultrasound oily sludge deoiling.

  16. Ultrasound molecular imaging: Moving toward clinical translation.

    PubMed

    Abou-Elkacem, Lotfi; Bachawal, Sunitha V; Willmann, Jürgen K

    2015-09-01

    Ultrasound is a widely available, cost-effective, real-time, non-invasive and safe imaging modality widely used in the clinic for anatomical and functional imaging. With the introduction of novel molecularly-targeted ultrasound contrast agents, another dimension of ultrasound has become a reality: diagnosing and monitoring pathological processes at the molecular level. Most commonly used ultrasound molecular imaging contrast agents are micron sized, gas-containing microbubbles functionalized to recognize and attach to molecules expressed on inflamed or angiogenic vascular endothelial cells. There are several potential clinical applications currently being explored including earlier detection, molecular profiling, and monitoring of cancer, as well as visualization of ischemic memory in transient myocardial ischemia, monitoring of disease activity in inflammatory bowel disease, and assessment of arteriosclerosis. Recently, a first clinical grade ultrasound contrast agent (BR55), targeted at a molecule expressed in neoangiogenesis (vascular endothelial growth factor receptor type 2; VEGFR2) has been introduced and safety and feasibility of VEGFR2-targeted ultrasound imaging is being explored in first inhuman clinical trials in various cancer types. This review describes the design of ultrasound molecular imaging contrast agents, imaging techniques, and potential future clinical applications of ultrasound molecular imaging.

  17. Automatic Contour Tracking in Ultrasound Images

    ERIC Educational Resources Information Center

    Li, Min; Kambhamettu, Chandra; Stone, Maureen

    2005-01-01

    In this paper, a new automatic contour tracking system, EdgeTrak, for the ultrasound image sequences of human tongue is presented. The images are produced by a head and transducer support system (HATS). The noise and unrelated high-contrast edges in ultrasound images make it very difficult to automatically detect the correct tongue surfaces. In…

  18. [Ultrasound in the management of inflammatory dermatosis].

    PubMed

    Habicheyn Hiar, S; Segura Palacios, J M; Bernal Ruiz, A I

    2015-11-01

    Cutaneous ultrasound is a dermatological diagnostic imaging technique based on the interaction of high-frequency ultrasounds with the skin. Because it is non-invasive, rapid and accessible, it has increasingly wide clinical applications. This article reviews its use in the management of inflammatory dermatological diseases.

  19. Musculoskeletal ultrasound for sports injuries.

    PubMed

    Tok, F; Özçakar, L; De Muynck, M; Kara, M; Vanderstraeten, G

    2012-12-01

    Each day, the role of musculoskeletal ultrasound (US) in the management of sports injuries is being consolidated. Yet, there is no doubt that the probe of US is (should be) the stethoscope of musculoskeletal physicians dealing with sports medicine. Not only for the diagnosis, but also for the close follow-up of the athletes and during likely onward interventions for their treatment, would US be of paramount importance. Accordingly, in this review paper on common sports injuries, we tried to shed light into the actual role of US in the clinical practice of sports medicine.

  20. Ultrasound mediated transdermal drug delivery.

    PubMed

    Azagury, Aharon; Khoury, Luai; Enden, Giora; Kost, Joseph

    2014-06-01

    Transdermal drug delivery offers an attractive alternative to the conventional drug delivery methods of oral administration and injections. However, the stratum corneum serves as a barrier that limits the penetration of substances to the skin. Application of ultrasound (US) irradiation to the skin increases its permeability (sonophoresis) and enables the delivery of various substances into and through the skin. This review presents the main findings in the field of sonophoresis in transdermal drug delivery as well as transdermal monitoring and the mathematical models associated with this field. Particular attention is paid to the proposed enhancement mechanisms and future trends in the fields of cutaneous vaccination and gene therapy.

  1. Pelvic Floor Ultrasound: A Review.

    PubMed

    Dietz, Hans Peter

    2017-03-01

    Female pelvic floor dysfunction encompasses a number of prevalent conditions and includes pelvic organ prolapse, urinary and fecal incontinence, obstructed defecation, and sexual dysfunction. In most cases neither etiology nor pathophysiology are well understood. Imaging has great potential to enhance both research and clinical management capabilities, and to date this potential is underutilized. Of the available techniques such as x-ray, computed tomography, magnetic resonance imaging, and ultrasound, the latter is generally superior for pelvic floor imaging, especially in the form of perineal or translabial imaging. The technique is safe, simple, cheap, easily accessible and provides high spatial and temporal resolutions.

  2. Ultrasound findings in trisomy 22.

    PubMed

    Schwendemann, Wade D; Contag, Stephen A; Koty, Patrick P; Miller, Richard C; Devers, Patricia; Watson, William J

    2009-02-01

    We sought to identify the characteristic sonographic findings of fetal trisomy 22 by performing a retrospective review of nine cases of fetal trisomy 22. All cases of chromosomal mosaicism were excluded, as were first-trimester losses. Indications for sonography, gestational age, and sonographically detected fetal anomalies were analyzed. The majority of patients were referred for advanced maternal age or abnormal ultrasound findings on screening exam. Oligohydramnios was the most common sonographic finding, present in 55% of affected fetuses. Intrauterine growth restriction and increased nuchal thickness were slightly less frequent.

  3. Orthobiologic Interventions Using Ultrasound Guidance.

    PubMed

    Malanga, Gerard; Abdelshahed, Dena; Jayaram, Prathap

    2016-08-01

    The application of regenerative therapies for the treatment of musculoskeletal conditions has emerged over the last decade with recent acceleration. These include prolotherapy, platelet-rich plasma, and mesenchymal stem cell therapy. These strategies augment the body's innate physiology to heal pathologic processes. This article presents an overview of platelet-rich plasma and mesenchymal stem cell therapy for the treatment of musculoskeletal injuries. A brief literature review is included, as are techniques for the use of ultrasound guidance to assist with these procedures.

  4. Pulse Compression Techniques for Laser Generated Ultrasound

    NASA Technical Reports Server (NTRS)

    Anastasi, R. F.; Madaras, E. I.

    1999-01-01

    Laser generated ultrasound for nondestructive evaluation has an optical power density limit due to rapid high heating that causes material damage. This damage threshold limits the generated ultrasound amplitude, which impacts nondestructive evaluation inspection capability. To increase ultrasound signal levels and improve the ultrasound signal-to-noise ratio without exceeding laser power limitations, it is possible to use pulse compression techniques. The approach illustrated here uses a 150mW laser-diode modulated with a pseudo-random sequence and signal correlation. Results demonstrate the successful generation of ultrasonic bulk waves in aluminum and graphite-epoxy composite materials using a modulated low-power laser diode and illustrate ultrasound bandwidth control.

  5. Ultrasound microbubble contrast and current clinical applications.

    PubMed

    Dindyal, Shiva; Kyriakides, Constantinos

    2011-01-01

    Ultrasound imaging is widely used worldwide principally because it is cheap, easily available and contains no exposure to ionizing radiation. The advent of microbubble ultrasound contrast has further increased the diagnostic sensitivity and specificity of this technique thus widening its clinical applications. The third generation of ultrasound contrast agents consist of sulphur hexafluoride microbubbles encased in a phospholipid shell. This review will elaborate on the pharmacology, safety profile and method of action of these agents. We also aim to discuss the ever expanding uses for contrast enhanced ultrasound in a number of clinical specialities which include the liver, kidney, prostate, sentinel node detection, vascular tree and endovascular stent surveillance. We will also discuss some of the recent patents regarding the future uses of ultrasound microbubble contrast and recent technological advances in clinical applications.

  6. Ultrasound Molecular Imaging and Drug Delivery.

    PubMed

    Caskey, Charles F

    2017-03-02

    Ultrasound is a rapidly advancing field with many emerging diagnostic and therapeutic applications. For diagnostics, new vascular targets are routinely identified and mature technologies are being translated to humans, while other recent innovations may bring about the creation of acoustic reporter genes and micron-scale resolution with ultrasound. As a cancer therapy, ultrasound is being explored as an adjuvant to immune therapies and to deliver acoustically or thermally active drugs to tumor regions. Ultrasound-enhanced delivery across the blood brain barrier (BBB) could potentially be very impactful for brain cancers and neurodegenerative diseases where the BBB often impedes the delivery of therapeutic molecules. In this minireview, we provide an overview of these topics in the field of ultrasound that are especially relevant to the interests of World Molecular Imaging Society.

  7. Microbubbles and ultrasound: a bird's eye view.

    PubMed

    Kaul, Sanjiv

    2004-01-01

    Gas-filled microbubbles were initially used as ultrasound contrast agent because of their intravascular rheology, which is similar to that of red blood cells. Their transit through tissue can thus be quantified with ultrasound. More recently, these bubbles have been successfully used for molecular imaging by incorporating ligands on their surfaces that will adhere to cellular and other components within the microvasculature and can be detected by ultrasound. These bubbles have also been used for delivery of genes and drugs which can be released locally by disruption of the bubbles with high-energy ultrasound. Finally, bioeffects produced by localized ultrasound disruption of microbubbles have been shown to induce angiogenesis. This brief review will provide a bird's eye view of these applications.

  8. High-intensity therapeutic ultrasound: metrological requirements versus clinical usage

    NASA Astrophysics Data System (ADS)

    Aubry, J.-F.

    2012-10-01

    High-intensity therapeutic ultrasound (HITU) is an appealing non-invasive, non-ionizing therapeutic modality with a wide range of tissue interactions ranging from transient permeabilization of cell membranes to thermal ablation. The ability to guide and monitor the treatment with an associated ultrasonic or magnetic resonance imaging device has resulted in a dramatic rise in the clinical use of therapeutic ultrasound in the past two decades. Nevertheless, the range of clinical applications and the number of patients treated has grown at a much higher pace than the definition of standards. In this paper the metrological requirements of the therapeutic beams are reviewed and are compared with the current clinical use of image-guided HITU mostly based on a practical approach. Liver therapy, a particularly challenging clinical application, is discussed to highlight the differences between some complex clinical situations and the experimental conditions of the metrological characterization of ultrasonic transducers.

  9. Ultrasound-guided needle aspiration of amoebic liver abscess.

    PubMed Central

    Ramani, A.; Ramani, R.; Kumar, M. S.; Lakhkar, B. N.; Kundaje, G. N.

    1993-01-01

    This prospective study was carried out on 200 patients with clinically, ultrasonographically and serologically confirmed amoebic liver abscess. The role of ultrasound-guided needle aspiration in addition to medications was evaluated compared to drug treatment alone. Both the groups were monitored clinically and sonographically for up to 6 months after diagnosis. The initial response (after 15 days) was better in the aspirated group (P < 0.05) but resolution of abscess after 6 months were similar. There was a more rapid clinical response in the aspirated group, particularly in those with larger (> 6 cm) abscesses and there were no complications. Percutaneous ultrasound-guided needle aspiration is a safe diagnostic and therapeutic approach which enhances clinical recovery, accelerates resolution, especially in large abscesses, and prevents complications. PMID:8346134

  10. Ultrasound-assisted biodiesel production from Camelina sativa oil.

    PubMed

    Sáez-Bastante, J; Ortega-Román, C; Pinzi, S; Lara-Raya, F R; Leiva-Candia, D E; Dorado, M P

    2015-06-01

    The main drawbacks of biodiesel production are high reaction temperatures, stirring and time. These could be alleviated by aiding transesterification with alternative energy sources, i.e. ultrasound (US). In this study, biodiesel was obtained from Camelina sativa oil, aided with an ultrasonic probe (20kHz, 70% duty cycle, 50% amplitude). Design of experiments included the combination of sonication and agitation cycles, w/wo heating (50°C). To gain knowledge about the implications of the proposed methodology, conventional transesterification was optimized, resulting in higher needs on catalyst concentration and reaction time, compared to the proposed reaction. Although FAME content met EN 14103 standard, FAME yields were lower than those provided by US-assisted transesterification. Energy consumption measurements showed that ultrasound assisted transesterification required lower energy, temperature, catalyst and reaction time.

  11. Automated segmentation of breast lesions in ultrasound images.

    PubMed

    Liu, Xu; Huo, Zhimin; Zhang, Jiwu

    2005-01-01

    Breast cancer is one of the leading causes of death in women. As a convenient and safe diagnosis method, ultrasound is most commonly used second to mammography for early detection and diagnosis of breast cancer. Here we proposed an automatic method to segment lesions in ultrasound images. The images are first filtered with anisotropic diffusion algorithm to remove speckle noise. The edge is enhanced to emphasize the lesion regions. Normalized cut is a graph theoretic that admits combination of different features for image segmentation, and has been successfully used in object parsing and grouping. In this paper we combine normalized cut with region merging method for the segmentation. The merging criteria are derived from the empirical rules used by radiologists when they interpret breast images. In the performance evaluation, we compared the computer-detected lesion boundaries with manually delineated borders. The experimental results show that the algorithm has efficient and robust performance for different kinds of lesions.

  12. Ultrasound assisted enzyme catalyzed degradation of Cetirizine dihydrochloride.

    PubMed

    Sutar, Rahul S; Rathod, Virendra K

    2015-05-01

    Cetirizine dihydrochloride, a pharmaceutical drug of the class antihistamines is frequently detected in wastewater samples. In the present work, the degradation of Cetirizine dihydrochloride is carried out using a novel technique of laccase enzyme as a catalyst under the influence of ultrasound irradiation. Effect of various process parameters such as enzyme loading, temperature, power, duty cycle, frequency and speed of agitation has been studied along with identification of the degradation intermediates. The maximum degradation of 91% is achieved at optimized experimental parameters such as 0.02% enzyme loading (w/v), 50°C temperature, power input of 100 W, 25 kHz frequency and 50% duty cycle with agitation speed of 200 rpm. It is observed that enzymatic degradation of Cetirizine dihydrochloride under the influence of ultrasound irradiation not only enhances the degradation but also reduces the time of degradation as compared to conventional enzymatic degradation technique.

  13. Ultrasound vibrometry using orthogonal- frequency-based vibration pulses.

    PubMed

    Zheng, Yi; Yao, Aiping; Chen, Shigao; Urban, Matthew W; Lin, Haoming; Chen, Xin; Guo, Yanrong; Chen, Ke; Wang, Tianfu; Chen, Siping

    2013-11-01

    New vibration pulses are developed for shear wave generation in a tissue region with preferred spectral distributions for ultrasound vibrometry applications. The primary objective of this work is to increase the frequency range of detectable harmonics of the shear wave. The secondary objective is to reduce the required peak intensity of transmitted pulses that induce the vibrations and shear waves. Unlike the periodic binary vibration pulses, the new vibration pulses have multiple pulses in one fundamental period of the vibration. The pulses are generated from an orthogonal-frequency wave composed of several sinusoidal signals, the amplitudes of which increase with frequency to compensate for higher loss at higher frequency in tissues. The new method has been evaluated by studying the shear wave propagation in in vitro chicken and swine liver. The experimental results show that the new vibration pulses significantly increase tissue vibration with a reduced peak ultrasound intensity, compared with the binary vibration pulses.

  14. Enhancement of Sonochemical Reaction by Dual-Pulse Ultrasound

    NASA Astrophysics Data System (ADS)

    Xu, Zheng; Yasuda, Keiji

    2011-07-01

    In order to apply sonochemistry in wastewater treatment, enhancement of sonochemical reaction is necessary. Oxidation of potassium iodide and the degradation of acid orange 7 in aqueous solution using ultrasound irradiation were performed at 490 kHz. Power-modulated pulsed waves were employed and the enhancement of reaction amount was observed compared with using continuous wave. The enhancement ratio for irradiation to rigid wall was larger than that for irradiation to free surface. Moreover, the best modulated pulsed on time was experimentally determined and the effect of the superposition of pulsed waves (dual-pulse) was studied. Enhancement was also observed and calculated separately when using dual-pulse ultrasound. The enhancement upon the use of the dual-transducer was ascribed to the enlargement of sonochemical reaction field. The enhancement upon the incorporating pulsed waves was ascribed to both the reduction of reaction threshold effect and the residual acoustical pressure at the pulsed off time.

  15. Chorioamniotic Separation Found on Obstetric Ultrasound and Perinatal Outcome

    PubMed Central

    Bibbo, Carolina; Little, Sarah E.; Bsat, Jad; Botka, Kris Ann; Benson, Carol B.; Robinson, Julian N.

    2016-01-01

    Objective This study aims to evaluate pregnancy outcomes in patients with spontaneous and iatrogenic chorioamniotic separation diagnosed by ultrasound after 17 weeks. Methods This is a retrospective cohort study of women with a singleton pregnancy who were diagnosed with chorioamniotic separation (n = 106) after 17 weeks' gestation from January 2000 to January 2013. Patients with chorioamniotic separation were compared with a group of patients who had obstetric ultrasounds without a diagnosis of chorioamniotic separation. Those without chorioamniotic separation were matched (1:1) on gestational age on the date of the ultrasound ( ± 2 weeks) (n = 106). The primary outcome was preterm delivery (< 37 weeks). Secondary outcomes included intrauterine growth restriction, stillbirth, and neonatal morbidity. Results The rate of preterm delivery was significantly higher for those with chorioamniotic separation than for those without (57.5 vs. 17.1%, p < 0.0001). There were no significant differences in the rate of aneuploidy, intrauterine growth restriction, stillbirth, or neonatal demise. The rate of stillbirth was significantly higher among those with chorioamniotic separation diagnosed before 24 weeks as compared with those diagnosed after 24 weeks (9.7 vs. 0%, p = 0.03). Conclusions Chorioamniotic separation is associated with preterm delivery. If diagnosed before 24 weeks, the rate of stillbirth is significantly higher. PMID:27683622

  16. Effects of nonlinear propagation in ultrasound contrast agent imaging.

    PubMed

    Tang, Meng-Xing; Kamiyama, Naohisa; Eckersley, Robert J

    2010-03-01

    This paper investigates two types of nonlinear propagation and their effects on image intensity and contrast-to-tissue ratio (CTR) in contrast ultrasound images. Previous studies have shown that nonlinear propagation can occur when ultrasound travels through tissue and microbubble clouds, making tissue farther down the acoustic path appear brighter in pulse inversion (PI) images, thus reducing CTR. In this study, the effect of nonlinear propagation through tissue or microbubbles on PI image intensity and CTR are compared at low mechanical index. A combination of simulation and experiment with SonoVue microbubbles were performed using a microbubble dynamics model, a laboratory ultrasound system and a clinical prototype scanner. The results show that, close to the bubble resonance frequency, nonlinear propagation through a bubble cloud of a few centimeter thickness with a modest concentration (1:10000 dilution of SonoVue microbubbles) is much more significant than through tissue-mimicking material. Consequently, CTR in regions distal to the imaging probe is greatly reduced for nonlinear propagation through the bubble cloud, with as much as a 12-dB reduction compared with nonlinear propagation through tissue-mimicking material. Both types of nonlinear propagation cause only a small change in bubble PI signals at the bubble resonance frequency. When the driving frequency increases beyond bubble resonance, nonlinear propagation through bubbles is greatly reduced in absolute values. However because of a greater reduction in nonlinear scattering from bubbles at higher frequencies, the corresponding CTR is much lower than that at bubble resonance frequency.

  17. Delimitation of the lung region with distributed ultrasound transducers

    NASA Astrophysics Data System (ADS)

    Cardona Cárdenas, Diego Armando; Furuie, Sérgio Shiguemi

    2016-04-01

    One technique used to infer and monitor patient's respiratory conditions is the electrical impedance tomography (EIT). This provides images with information about lung function. The EIT image contrast is dependent on the variation of electrical impedance, therefore, this image does not provide anatomical details in border regions of several organs. To contribute to a clinical solution, we propose a new method to delimit regions of interest such as the pulmonary region and to improve the reconstruction quality of the EIT. Using a Matlab Toolbox k-wave, the ultrasound propagation phenomenon in homogeneous medium without patient (Reference) and with thoracic models were simulated, separately via a set of several ultrasound transducers distributed around the chest. After pulse emission by a transducer (TR), all received signals were compared considering the two sets of signals. If the energy relation between parts of the signals does not exceed an empirical threshold (30% in this study), a partial mask is generated between the transmitter and the receptor. This process was repeated until all 128 transducers are considered as TR-emitters. The 128 transducers (150kHz) are uniformly distributed. The evaluation was made by visually comparing the resulting images with the respective simulated object. A simple approach was presented to delimit high contrast organs with ultrasound transducers distributed around the patient. This approach allows other lower contrast objects to become invisible by varying the threshold limit. The investigation, based on numerical simulations of ultrasonic propagation, has shown promising results in the delimitation of the pulmonary region.

  18. Feature selection applied to ultrasound carotid images segmentation.

    PubMed

    Rosati, Samanta; Molinari, Filippo; Balestra, Gabriella

    2011-01-01

    The automated tracing of the carotid layers on ultrasound images is complicated by noise, different morphology and pathology of the carotid artery. In this study we benchmarked four methods for feature selection on a set of variables extracted from ultrasound carotid images. The main goal was to select those parameters containing the highest amount of information useful to classify the pixels in the carotid regions they belong to. Six different classes of pixels were identified: lumen, lumen-intima interface, intima-media complex, media-adventitia interface, adventitia and adventitia far boundary. The performances of QuickReduct Algorithm (QRA), Entropy-Based Algorithm (EBR), Improved QuickReduct Algorithm (IQRA) and Genetic Algorithm (GA) were compared using Artificial Neural Networks (ANNs). All methods returned subsets with a high dependency degree, even if the average classification accuracy was about 50%. Among all classes, the best results were obtained for the lumen. Overall, the four methods for feature selection assessed in this study return comparable results. Despite the need for accuracy improvement, this study could be useful to build a pre-classifier stage for the optimization of segmentation performance in ultrasound automated carotid segmentation.

  19. Ultrasound for the Anesthesiologists: Present and Future

    PubMed Central

    Terkawi, Abdullah S.; Karakitsos, Dimitrios; Elbarbary, Mahmoud; Blaivas, Michael; Durieux, Marcel E.

    2013-01-01

    Ultrasound is a safe, portable, relatively inexpensive, and easily accessible imaging modality, making it a useful diagnostic and monitoring tool in medicine. Anesthesiologists encounter a variety of emergent situations and may benefit from the application of such a rapid and accurate diagnostic tool in their routine practice. This paper reviews current and potential applications of ultrasound in anesthesiology in order to encourage anesthesiologists to learn and use this useful tool as an adjunct to physical examination. Ultrasound-guided peripheral nerve blockade and vascular access represent the most popular ultrasound applications in anesthesiology. Ultrasound has recently started to substitute for CT scans and fluoroscopy in many pain treatment procedures. Although the application of airway ultrasound is still limited, it has a promising future. Lung ultrasound is a well-established field in point-of-care medicine, and it could have a great impact if utilized in our ORs, as it may help in rapid and accurate diagnosis in many emergent situations. Optic nerve sheath diameter (ONSD) measurement and transcranial color coded duplex (TCCD) are relatively new neuroimaging modalities, which assess intracranial pressure and cerebral blood flow. Gastric ultrasound can be used for assessment of gastric content and diagnosis of full stomach. Focused transthoracic (TTE) and transesophageal (TEE) echocardiography facilitate the assessment of left and right ventricular function, cardiac valve abnormalities, and volume status as well as guiding cardiac resuscitation. Thus, there are multiple potential areas where ultrasound can play a significant role in guiding otherwise blind and invasive interventions, diagnosing critical conditions, and assessing for possible anatomic variations that may lead to plan modification. We suggest that ultrasound training should be part of any anesthesiology training program curriculum. PMID:24348179

  20. Pulsed Ultrasound Enhances Nanoparticle Penetration into Breast Cancer Spheroids

    PubMed Central

    Grainger, Stephanie J.; Serna, Juliana Valencia; Sunny, Steffi; Zhou, Yun; Deng, Cheri X.; El-Sayed, Mohamed E.H.

    2010-01-01

    Effective treatment of solid tumors requires homogenous distribution of anticancer drugs within the entire tumor volume to deliver lethal concentrations to resistant cancer cells and tumor-initiating cancer stem cells. However, penetration of small molecular weight chemotherapeutic agents and drug-loaded polymeric and lipid particles into the hypoxic and necrotic regions of solid tumors remains a significant challenge. This article reports the results of pulsed ultrasound enhanced penetration of nano-sized fluorescent particles into MCF-7 breast cancer spheroids (300-350 μm diameter) as a function of particle size and charge. With pulsed ultrasound application in the presence of microbubbles, small (20 nm) particles achieve 6-20 folds higher penetration and concentration in the spheroid's core compared to those not exposed to ultrasound. Increase in particle size to 40 nm and 100 nm results in their effective penetration into the spheroid's core to 9 and 3 folds, respectively. In addition, anionic carboxylate particles achieved higher penetration (2.3, 3.7, and 4.7 folds) into the core (0.25r) of MCF-7 breast cancer spheroids compared to neutral (2.2, 1.9, and 2.4 folds) and cationic particles (1.5, 1.4 and 1.9 folds) upon US exposure for 30, 60, and 90 seconds under the same experimental conditions. These results demonstrate the feasibility of utilizing pulsed ultrasound to increase the penetration of nano-sized particles into MCF-7 spheroids mimicking tumor tissue. The effects of particle properties on the penetration enhancement were also illustrated. PMID:20957996

  1. Quantitative ultrasound images generated by a PE-CMOS sensor array: scatter modeling and image restoration

    NASA Astrophysics Data System (ADS)

    Liu, Chu-Chuan; Lo, Shih-Chung Ben; Freedman, Matthew T.; Lasser, Marvin E.; Lasser, Bob; Kula, John; Wang, Yue Joseph

    2007-03-01

    In the projection geometry, the detected ultrasound energy through a soft-tissue is mainly attributed to the attenuated primary intensity and the scatter intensity. In order to extract ultrasound image of attenuated primary beam out of the detected raw data, the scatter component must be carefully quantified for restoring the original image. In this study, we have designed a set of apparatus to modeling the ultrasound scattering in soft-tissue. The employed ultrasound imaging device was a C-Scan (projection) prototype using a 4th generation PE-CMOS sensor array (model I400, by Imperium Inc., Silver Spring, MD) as the detector. Right after the plane wave ultrasound transmitting through a soft-tissue mimicking material (Zerdine, by CIRS Inc., Norfolk, VA), a ring aperture is used to collimate the signal before reaching the acoustic lens and the PE-CMOS sensor. Three sets of collimated ring images were acquired and analyzed to obtain the scattering components as a function of the off-center distance. Several pathological specimens and breast phantoms consisting of simulated breast tissue with masses, cysts and microcalcifications were imaged by the same C-Scan imaging prototype. The restoration of these ultrasound images were performed by using a standard deconvolution computation. Our study indicated that the resultant images show shaper edges and detailed features as compared to their unprocessed counterparts.

  2. [Study on the spectrophotometric determination of hydroxyl free radical from low power trench-type ultrasound].

    PubMed

    Cao, Yan-ping; Yuan, Ying-mao; Zhu, Yu-chen

    2012-05-01

    Under the condition of different pH (7-11) and different ethanol volume fraction (45% to 85%), the ultraviolet-visible absorption spectra of malachite green were studied in neutral and alkaline ethanol solution, the maximum absorption wavelength at 620 nm was found, and the matching degree of standard curve was better established. In low power trench-type ultrasound apparatus, the absorption of the malachite green solution was measured under ultrasound and non-ultrasound, respectively. the difference values of the ultraviolet absorption of the malachite green solution under low power trench-type ultrasound were measured results of the hydroxyl free radical oxidation degrading malachite green, therefore hydroxyl free radical from low power trench-type ultrasound was determined indirectly. Then the contents of hydroxyl free radical in four conditions were measured. The detection limit of the method of 8.4 x 10(-6) mmol x L(-1) and the relative standard deviation of the method of 9.4 x 10(-5) - 3.7 x 10(-4) mmol x L(-1) were determined, a higher testing precision and good reproducibility were confirmed. It can be applied for fast detection of neutral and alkaline ethanol solution system in the case of very low concentration of hydroxyl free radicals. Since malachite green is heat sensitive, so compared to measuring temperature, the method possessed better functions for thermal effects of ultrasound.

  3. Solid volume fraction estimation of bone:marrow replica models using ultrasound transit time spectroscopy.

    PubMed

    Wille, Marie-Luise; Langton, Christian M

    2016-02-01

    The acceptance of broadband ultrasound attenuation (BUA) for the assessment of osteoporosis suffers from a limited understanding of both ultrasound wave propagation through cancellous bone and its exact dependence upon the material and structural properties. It has recently been proposed that ultrasound wave propagation in cancellous bone may be described by a concept of parallel sonic rays; the transit time of each ray defined by the proportion of bone and marrow propagated. A Transit Time Spectrum (TTS) describes the proportion of sonic rays having a particular transit time, effectively describing the lateral inhomogeneity of transit times over the surface aperture of the receive ultrasound transducer. The aim of this study was to test the hypothesis that the solid volume fraction (SVF) of simplified bone:marrow replica models may be reliably estimated from the corresponding ultrasound transit time spectrum. Transit time spectra were derived via digital deconvolution of the experimentally measured input and output ultrasonic signals, and compared to predicted TTS based on the parallel sonic ray concept, demonstrating agreement in both position and amplitude of spectral peaks. Solid volume fraction was calculated from the TTS; agreement between true (geometric calculation) with predicted (computer simulation) and experimentally-derived values were R(2)=99.9% and R(2)=97.3% respectively. It is therefore envisaged that ultrasound transit time spectroscopy (UTTS) offers the potential to reliably estimate bone mineral density and hence the established T-score parameter for clinical osteoporosis assessment.

  4. The finite element method for micro-scale modeling of ultrasound propagation in cancellous bone.

    PubMed

    Vafaeian, B; El-Rich, M; El-Bialy, T; Adeeb, S

    2014-08-01

    Quantitative ultrasound for bone assessment is based on the correlations between ultrasonic parameters and the properties (mechanical and physical) of cancellous bone. To elucidate the correlations, understanding the physics of ultrasound in cancellous bone is demanded. Micro-scale modeling of ultrasound propagation in cancellous bone using the finite-difference time-domain (FDTD) method has been so far utilized as one of the approaches in this regard. However, the FDTD method accompanies two disadvantages: staircase sampling of cancellous bone by finite difference grids leads to generation of wave artifacts at the solid-fluid interface inside the bone; additionally, this method cannot explicitly satisfy the needed perfect-slip conditions at the interface. To overcome these disadvantages, the finite element method (FEM) is proposed in this study. Three-dimensional finite element models of six water-saturated cancellous bone samples with different bone volume were created. The values of speed of sound (SOS) and broadband ultrasound attenuation (BUA) were calculated through the finite element simulations of ultrasound propagation in each sample. Comparing the results with other experimental and simulation studies demonstrated the capabilities of the FEM for micro-scale modeling of ultrasound in water-saturated cancellous bone.

  5. Extension of mushroom shelf-life by ultrasound treatment combined with high pressure argon

    NASA Astrophysics Data System (ADS)

    Lagnika, Camel; Zhang, Min; Nsor-Atindana, John; Tounkara, Fatoumata

    2014-03-01

    Effects of ultrasound, high pressure argon, and treatments comprising their combinations on physicochemical and microbiological characteristics of white mushrooms were studied during 9 days of storage at 4°C. High pressure argon treatments were relatively effective in retaining firmness and were found to maintain the cell integrity. White mushrooms firmness after 9 days of storage was increased from 2.79 N for untreated mushrooms up to 3.01, 3.24, 3.58 N for ultrasound, treatments comprising ultrasound and high pressure argon, high pressure argon, respectively. Similarly, the loss of water, ascorbic acid and total soluble solid in fresh mushroom was also greatly reduced by the high pressure argon treatment. The ultrasound treatment followed by treatments comprising ultrasound and high pressure argon and high pressure argon, respectively exhibited a pronounced effect on retarding browning and in delaying mesophilic and psychrotrophic bacteria, yeasts and moulds growth in white mushroom, compared to the control during 9 days of cold storage. Treatments comprising ultrasound and high pressure argon treatment delayed pseudomonas growth, implying that it could extend shelf life of white mushrooms to 9 days at 4°C.

  6. Monitoring of Diaphragm Position in Pulsatile Pnumatic Ventricular Assisted Device by Ultrasound Sensor

    NASA Astrophysics Data System (ADS)

    Kamimura, Tadayuki; Homma, Akihiko; Tsukiya, Tomonori; Kakuta, Yukihide; Lee, Hwansung; Tatsumi, Eisuke; Taenaka, Yoshiyuki; Kitamura, Soichiro

    A new method using ultrasound sensors to detect the diaphragm position of a ventricular assist device (VAD) was proposed. Two small ultrasound sensors of 2.4mm diameter were attached to the outside surface of blood chamber of a pneumatic VAD. The receiving crystal received the ultrasound from the transmitting crystal reflected by the diaphragm. The diaphragm position was calculated by using geometric relation among two sensors and ultrasound propagation time. Validity of this method was evaluated in a mock circulation test under various driving conditions of VAD by comparing the ultrasound signals with driving pressure waveforms. The ultrasound signals could detect full-fill (FF) and full-eject (FE) status shortly before the spikes appeared on pressure waves, which are currently available to detect FE and FF but accompanies excessive extension of the diaphragm. This method would be helpful to avoid overloading of diaphragm. Linear correlation was observed between the output from VAD and blood volume calculated from the change of diaphragm position multiplied by the heart rate. This monitoring method of diaphragm of a VAD was proven to have advantages over the current method toward better control of a pneumatic VAD.

  7. Combined effect of benzalkonium chloride and ultrasound against Listeria monocytogenes biofilm on plastic surface.

    PubMed

    Torlak, E; Sert, D

    2013-09-01

    This study was performed to evaluate the effectiveness of benzalkonium chloride combined with ultrasound in eliminating Listeria monocytogenes biofilm from polystyrene surface. The test strain of L. monocytogenes, previously classified as strong biofilm producer, was grown to form biofilm in tryptic soy broth at 20°C for 6 days in polystyrene specimen containers. The biofilms formed on surface of containers were treated with ultrasound alone, benzalkonium chloride (100 and 400 mg l(-1)) alone and their combination for three different exposure times (1, 5 and 15 min) at room temperature. Sonication was performed using an ultrasound bath at a constant ultrasound frequency of 35 kHz. After treatments, levels of biofilm biomass and viable cells in biofilm were determined using crystal violet staining and XTT assays, respectively. The combined treatment of ultrasound and benzalkonium chloride resulted in significant (P < 0·05) more decrease in the level of viable cells in the L. monocytogenes biofilm compared to individual treatments of benzalkonium chloride. Our results suggest that the combination of benzalkonium chloride with ultrasound is useful approach for the elimination of L. monocytogenes biofilms from plastic surfaces.

  8. Superiority of chlorhexidine 2%/alcohol 70% wipes in decontaminating ultrasound equipment

    PubMed Central

    Shukla, Bhavin; Howell, Victoria; Griffiths, Alicia; Thoppil, Anita; Liu, Monica; Young, Peter

    2014-01-01

    Ultrasound equipment is known to act as a reservoir for potentially pathogenic organisms. The aims of these studies were to establish current cleaning practices, to review the extent of bacterial contamination of ultrasound equipment in our hospital, to establish an effective cleaning regimen and to ensure that cleaning does not cause damage. A questionnaire was sent to all acute NHS hospitals in England to establish current cleaning practices. A review of our current practice was performed to establish the extent of bacterial contamination of ultrasound equipment currently in use. Laboratory studies compared cleaning the probes with soap and water with decontaminating with a chlorhexidine 2% and alcohol 70% wipe, including quantifying the residual effect. Accelerated aging was performed on the probe and staff surveyed to establish potential problems with using the wipes on the probe. The survey revealed that a variety of cleaning methods were used to decontaminate ultrasound probes; 57% of our ultrasound machines were contaminated with bacteria. The laboratory studies showed superiority of the chlorhexidine and alcohol wipes over soap and water due to a residual effect, both immediately after cleaning and after 24 hours. The staff survey demonstrated no apparent change in function of the probe after cleaning with the chlorhexidine wipes. Cleaning ultrasound probes with chlorhexidine and alcohol wipes is effective and provides additional protection against bacterial contamination due to its residual effect, and appears in the short term to have no detrimental effect on the probe. PMID:27433210

  9. Segmentation of tumor ultrasound image in HIFU therapy based on texture and boundary encoding

    NASA Astrophysics Data System (ADS)

    Zhang, Dong; Xu, Menglong; Quan, Long; Yang, Yan; Qin, Qianqing; Zhu, Wenbin

    2015-02-01

    It is crucial in high intensity focused ultrasound (HIFU) therapy to detect the tumor precisely with less manual intervention for enhancing the therapy efficiency. Ultrasound image segmentation becomes a difficult task due to signal attenuation, speckle effect and shadows. This paper presents an unsupervised approach based on texture and boundary encoding customized for ultrasound image segmentation in HIFU therapy. The approach oversegments the ultrasound image into some small regions, which are merged by using the principle of minimum description length (MDL) afterwards. Small regions belonging to the same tumor are clustered as they preserve similar texture features. The mergence is completed by obtaining the shortest coding length from encoding textures and boundaries of these regions in the clustering process. The tumor region is finally selected from merged regions by a proposed algorithm without manual interaction. The performance of the method is tested on 50 uterine fibroid ultrasound images from HIFU guiding transducers. The segmentations are compared with manual delineations to verify its feasibility. The quantitative evaluation with HIFU images shows that the mean true positive of the approach is 93.53%, the mean false positive is 4.06%, the mean similarity is 89.92%, the mean norm Hausdorff distance is 3.62% and the mean norm maximum average distance is 0.57%. The experiments validate that the proposed method can achieve favorable segmentation without manual initialization and effectively handle the poor quality of the ultrasound guidance image in HIFU therapy, which indicates that the approach is applicable in HIFU therapy.

  10. Ultrasound calibration using intensity-based image registration: for application in cardiac catheterization procedures

    NASA Astrophysics Data System (ADS)

    Ma, Y. L.; Rhode, K. S.; Gao, G.; King, A. P.; Chinchapatnam, P.; Schaeffter, T.; Hawkes, D. J.; Razavi, R.; Penney, G. P.

    2008-03-01

    We present a novel method to calibrate a 3D ultrasound probe which has a 2D transducer array. By optically tracking a calibrated 3D probe we are able to produce extended field of view 3D ultrasound images. Tracking also enables us to register our ultrasound images to other tracked and calibrated surgical instruments or to other tracked and calibrated imaging devices. Our method applies rigid intensity-based image registration to three or more ultrasound images. These images can either be of a simple phantom, or could potentially be images of the patient. In this latter case we would have an automated calibration system which required no phantom, no image segmentation and was optimized to the patient's ultrasound characteristics i.e. speed of sound. We have carried out experiments using a simple calibration phantom and with ultrasound images of a volunteer's liver. Results are compared to an independent gold-standard. These showed our method to be accurate to 1.43mm using the phantom images and 1.56mm using the liver data, which is slightly better than the traditional point-based calibration method (1.7mm in our experiments).

  11. Comparison of IOL--master and ultrasound biometry in preoperative intra ocular lens (IOL) power calculation.

    PubMed

    Kolega, Marija Škara; Kovačević, Suzana; Čanović, Samir; Pavičić, Ana Didović; Bašić, Jadranka Katušić

    2015-03-01

    Postoperative refractive outcome largely depends on the accuracy of calculating power of implanted IOL. Lens power calculation can be done by conventional ultrasound biometry and partial coherence laser interferometry (IOL Master). The aim was to compare the accuracy of IOL power calculations using conventional ultrasound biometry and partial coherence laser interferometry.40 eyes were included in this prospective randomized trial. Twenty eyes underwent IOL master and 20 eyes had aplanation ultrasound biometry. There were included only eyes with age-related cataract and postoperative natural visual acuity (VA) 0.7. Visual acuity was performed 6 weeks after cataract surgery. After 6 weeks best natural visual acuity were 0.9 (± 0.1) in IOL-Master group and 0.85 (± 0.15) in ultrasound biometry. The postoperative mean absolute refractive error was 0.75 (± 0.5) D for ultrasound biometry and 0.50 (± 0.50) D for IOL-Master. Optical biometry with the IOL-Master proved to be slightly more accurate than ultrasound biometry for IOL power calculation.

  12. Randomized study of effectiveness of computerized ultrasound simulators for an introductory course for residents in Brazil

    PubMed Central

    2016-01-01

    Purpose: This study aimed to assess the impact of ultrasound simulation (SonoSim) on educational outcomes of an introductory point-of-care ultrasound course compared to hands-on training with live models alone. Methods: Fifty-three internal medicine residents without ultrasound experience were randomly assigned to control or experimental groups. They participated in an introductory point-of-care ultrasound course covering eight topics in eight sessions from June 23, 2014 until July 18, 2014. Both participated in lecture and hands-on training, but experimental group received an hour of computerized simulator training instead of a second hour of hands-on training. We assessed clinical knowledge and image acquisition with written multiple-choice and practical exams, respectively. Of the 53 enrolled, 40 participants (75.5%) completed the course and all testing. Results: For the 30-item written exam, mean score of the experimental group was 23.1±3.4 (n=21) vs. 21.8±4.8 (n=19), (P>0 .05). For the practical exam, mean score for both groups was 8.7 out of 16 (P>0 .05). Conclusion: The substitution of eight hours of ultrasound simulation training for live model scanning in a 24 hour training course did not enhance performance on written and image acquisition tests in an introductory ultrasound course for residents. This result suggests that ultrasound simulation technology used as a substitute for live model training on an hour-for-hour basis, did not improve learning outcomes. Further investigation into simulation as a total replacement for live model training will provide a clearer picture of the efficacy of ultrasound simulators in medical education. PMID:27044782

  13. Cardiac Gene Expression Knockdown Using Small Inhibitory RNA-Loaded Microbubbles and Ultrasound

    PubMed Central

    McTiernan, Charles F.; Chen, Xucai; Klein, Edwin C.; Villanueva, Flordeliza S.

    2016-01-01

    RNA interference has potential therapeutic value for cardiac disease, but targeted delivery of interfering RNA is a challenge. Custom designed microbubbles, in conjunction with ultrasound, can deliver small inhibitory RNA to target tissues in vivo. The efficacy of cardiac RNA interference using a microbubble-ultrasound theranostic platform has not been demonstrated in vivo. Therefore, our objective was to test the hypothesis that custom designed microbubbles and ultrasound can mediate effective delivery of small inhibitory RNA to the heart. Microbubble and ultrasound mediated cardiac RNA interference was tested in transgenic mice displaying cardiac-restricted luciferase expression. Luciferase expression was assayed in select tissues of untreated mice (n = 14). Mice received intravenous infusion of cationic microbubbles bearing small inhibitory RNA directed against luciferase (n = 9) or control RNA (n = 8) during intermittent cardiac-directed ultrasound at mechanical index of 1.6. Simultaneous echocardiography in a separate group of mice (n = 3) confirmed microbubble destruction and replenishment during treatment. Three days post treatment, cardiac luciferase messenger RNA and protein levels were significantly lower in ultrasound-treated mice receiving microbubbles loaded with small inhibitory RNA directed against luciferase compared to mice receiving microbubbles bearing control RNA (23±7% and 33±7% of control mice, p<0.01 and p = 0.03, respectively). Passive cavitation detection focused on the heart confirmed that insonification resulted in inertial cavitation. In conclusion, small inhibitory RNA-loaded microbubbles and ultrasound directed at the heart significantly reduced the expression of a reporter gene. Ultrasound-targeted destruction of RNA-loaded microbubbles may be an effective image-guided strategy for therapeutic RNA interference in cardiac disease. PMID:27471848

  14. Treatment of chest wall tuberculosis with transdermal ultrasound-mediated drug delivery

    PubMed Central

    HAN, YI; ZHAO, QIUYUE; YU, DAPING; LIU, ZHIDONG

    2015-01-01

    Chest wall tuberculosis (TB) is an endemic disease with a large number of variants. The condition affects numerous parts of the body and can penetrate the skin to form chronic open ulcers. Current treatment methods include oral anti-TB drugs and surgery. However, conventional drug treatments are not effective due to the difficulty in achieving an effective local concentration, and certain patients are unable to tolerate surgery. The recurrence rate for chest wall TB is high following surgery, and may result in the prolonged healing of wounds in certain patients, as well as chronic sinusitis and fistula formation. To identify a safe, simple, less invasive and more clinically effective treatment method, the present study investigated transdermal ultrasound-mediated anti-TB drug delivery. A total of 186 patients were selected and randomly divided into transdermal ultrasound, surgery and oral anti-TB drug only groups. Rifampicin was the drug delivered by transdermal ultrasound. The cure and efficiency rates were shown to be 87.10 and 93.55%, respectively, in the ultrasound treatment group. No statistically significant difference was observed in the cure rates between the transdermal ultrasound and surgery groups; however, a statistically significant difference was identified in the cure rates between the transdermal ultrasound and oral anti-TB drug only groups. Therefore, transdermal ultrasound technology was shown to deliver anti-TB drugs quickly and directly, which resulted in a high local concentration of the drug, overcoming the problem of obtaining an effective local drug concentration. The observations demonstrated that transdermal ultrasound-mediated drug delivery is an effective method by which to control TB, particularly when compared with traditional oral anti-TB therapy and surgery. PMID:25780447

  15. Optical detection of ultrasound from optically rough surfaces using a custom CMOS sensor

    NASA Astrophysics Data System (ADS)

    Achamfuo-Yeboah, S. O.; Light, R. A.; Sharples, S. D.

    2015-01-01

    The optical detection of ultrasound from optically rough surfaces is severely limited when using a conventional interferometric or optical beam deflection (OBD) setup because the detected light is speckled. This means that complicated and expensive setups are required to detect ultrasound optically on rough surfaces. We present a CMOS integrated circuit that can detect laser ultrasound in the presence of speckle. The detector circuit is based on the simple knife edge detector. It is self-adapting and is fast, inxepensive, compact and robust. The CMOS circuit is implemented as a widefield array of 32×32 pixels. At each pixel the received light is compared with an adjacent pixel in order to determine the local light gradient. The result of this comparison is stored and used to connect each pixel to the positive or negative gradient output as appropriate (similar to a balanced knife edge detector). The perturbation of the surface due to ultrasound preserves the speckle distribution whilst deflecting it. The spatial disturbance of the speckle pattern due to the ultrasound is detected by considering each pair of pixels as a knife edge detector. The sensor can adapt itself to match the received optical speckle pattern in less than 0.1 μs, and then detect the ultrasound within 0.5 μs of adaptation. This makes it possible to repeatedly detect ultrasound from optically rough surfaces very quickly. The detector is capable of independent operation controlled by a local microcontroller, or it may be connected to a computer for more sophisticated configuration and control. We present the theory of its operation and discuss results validating the concept and operation of the device. We also present preliminary results from an improved design which grants a higher bandwidth, allowing for optical detection of higher frequency ultrasound.

  16. Comparison of three techniques for ultrasound-guided femoral nerve catheter insertion: A randomized, blinded trial

    PubMed Central

    Farag, Ehab; Atim, Abdulkadir; Ghosh, Raktim; Bauer, Maria; Sreenivasalu, Thilak; Kot, Michael; Kurz, Andrea; Dalton, Jarrod E.; Mascha, Edward J.; Mounir-Soliman, Loran; Zaky, Sherif; Esa, Wael Ali Sakr; Udeh, Belinda L.; Barsoum, Wael; Sessler, Daniel I.

    2014-01-01

    Background Ultrasound guidance for continuous femoral perineural catheters may be supplemented by electrical stimulation through a needle or through a stimulating catheter. We tested the primary hypothesis that ultrasound guidance alone is noninferior on both postoperative pain scores and opioid requirement and superior on at least one of the two. Secondarily, we compared all interventions on insertion time and incremental cost. Methods Patients having knee arthroplasty with femoral nerve catheters were randomly assigned to catheter insertion guided by: 1) ultrasound alone (n=147); 2) ultrasound and electrical stimulation through the needle (n=152); or, 3) ultrasound and electrical stimulation through both the needle and catheter (n=138). Noninferiority between any two interventions was defined for pain as no more than 0.5 points worse on a 0–10 Verbal Response Scale (VRS) scale and for opioid consumption as no more than 25% greater than the mean. Results The stimulating needle group was significantly noninferior to the stimulating catheter (difference (95% CI) in mean VRS pain score [stimulating needle versus stimulating catheter] of −0.16 (−0.61, 0.29), P<0.001; percent difference in mean IV morphine equivalent dose of −5% (−25%, 21%), P=0.002) and to ultrasound only (difference in mean VRS pain score of −0.28 (−0.72, 0.16), P<0.001; percent difference in mean IV morphine equivalent dose of −2% (−22%, 25%), P=0.006). In addition, the use of ultrasound alone for femoral nerve catheter insertion was faster and cheaper than the other two methods. Conclusion Ultrasound guidance alone without adding either stimulating needle or needle/catheter combination thus appears to be the best approach to femoral perineural catheters. PMID:24758775

  17. A study on influential factors of high-phosphorus wastewater treated by electrocoagulation-ultrasound.

    PubMed

    Li, Jiangping; Song, Chen; Su, Yixin; Long, Hai; Huang, Ta; Yeabah, Trokon Omarley; Wu, Wei

    2013-08-01

    A combined treatment of electrocoagulation and ultrasound was proposed to solve some problems which exist in the phosphorus removal processes in fine chemical industry. The intermittently discharged wastewater has the features of high initial phosphorus concentration and wide initial pH variation. The electrocoagulation-ultrasound effective performance for the removal of phosphorus was investigated. The results obtained from synthetic wastewater showed that the total phosphorus (TP) decreased from 86 to about 0.4 mg/L, and the removal efficiency reached about 99.6 %, when ultrasound was applied to the electrocoagulation cell under the optimum working conditions in 10 min. Comparatively, the TP removal efficiency of electrocoagulation group was 81.3 % and the ultrasound group has almost no change. Therefore, we can conclude that the electrocoagulation and ultrasound synergistic effect can effectively degrade high-phosphorus wastewater. We have discussed the impact of various parameters on the electrocoagulation-ultrasound based on the phosphorus removal efficiency. The results obtained from synthetic wastewater showed that the optimum working pH was found to be 6, allowing the effluent to be met the emission standards without pH adjustment. An increased current enhanced the speed of treatment significance, but higher current (>40 mA/cm(2)) enhanced ultrasonic cavitation effect causing flocculation ineffective. In addition, it was found that the optimum ultrasonic power was 4 W/cm(2) and the frequency was 20 kHz. The best ultrasound intervention and ultrasonic irradiation time were processed with electrocoagulation simultaneously. The results indicated that the electrocoagulation-ultrasound could be utilized as an attractive technique for removal of phosphate in the real wastewater.

  18. Ultrasound assessment of breast development: distinction between premature thelarche and precocious puberty.

    PubMed

    Youn, Inyoung; Park, Sung Hee; Lim, In Seok; Kim, Soo Jin

    2015-03-01

    OBJECTIVE. We analyzed the correlation between breast development and ultrasound-measured breast bud diameter. We also evaluated different breast ultrasound findings in pediatric subjects with precocious puberty and premature thelarche while comparing bone age and hormone levels. MATERIALS AND METHODS. We performed a retrospective study with a sample of 90 girls (mean age, 7.8 years) who underwent breast ultrasound for evaluation of early breast development between March 2011 and February 2013. We evaluated breast ultrasound grade, bud diameter, and clinical characteristics including bone age and hormone levels. Among the 90 girls, 69 were up to 8 years old (mean age, 7.3 years). We divided them into healthy, precocious puberty, and premature thelarche groups and evaluated the clinicoradiologic findings for each group. RESULTS. Breast ultrasound grade was correlated with age, bone age, bud diameter, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol (E2). Bud diameter was correlated with age, bone age, LH, FSH, and E2. However, the difference between bone age and chronological age was not correlated with ultrasound grade or bud diameter. Among 69 girls up to 8 years old, including 11 healthy girls (15.9%), 26 girls with precocious puberty (37.7%) (mean [SD] age, 7.3 years), and 32 girls with premature thelarche (46.4%) (mean age, 7.2 years), there were no significant differences in other variables except values for bone age (p = 0.001) and difference between bone age and chronological age (p < 0.001). CONCLUSION. Breast ultrasound might be useful for evaluating sexual development with respect to bud diameter or ultrasound grade. However, its ability to distinguish precocious puberty from premature thelarche is limited.

  19. Reversible and irreversible vascular bioeffects induced by ultrasound and microbubbles in chorioallantoic membrane model

    NASA Astrophysics Data System (ADS)

    Tarapacki, Christine; Kuebler, Wolfgang M.; Tabuchi, Arata; Karshafian, Raffi

    2017-03-01

    Background: The application of ultrasound and microbubbles at therapeutic conditions has been shown to improve delivery of molecules, cause vasoconstriction, modulate blood flow and induce a vascular shut down in in vivo cancerous tissues. The underlying mechanism has been associated with the interaction of ultrasonically-induced microbubble oscillation and cavitation with the blood vessel wall. In this study, the effect of ultrasound and microbubbles on blood flow and vascular architecture was studied using a fertilized chicken egg CAM (chorioallantoic membrane) model. Methods: CAM at day 12 of incubation (Hamburger-Hamilton stage 38-40) were exposed to ultrasound at varying acoustic pressures (160, 240 and 320 kPa peak negative pressure) in the presence of Definity microbubbles and 70 kDa FITC dextran fluorescent molecules. A volume of 50 µL Definity microbubbles were injected into a large anterior vein of the CAM prior to ultrasound exposure. The ultrasound treatment sequence consisted of 5 s exposure at 500 kHz frequency, 8 cycles and 1 kHz pulse repetition frequency with 5 s off for a total exposure of 2 minutes. Fluorescent videos and images of the CAM vasculature were acquired using intravital microscopy prior, during and following the ultrasound exposure. Perfusion was quantified by measuring the length of capillaries in a region of interest using Adobe Illustrator. Results and Discussion: The vascular bioeffects induced by USMB increased with acoustic peak negative pressure. At 160 kPa, no visible differences were observed compared to the control. At 240 kPa, a transient decrease in perfusion with subsequent recovery within 15 minutes was observed, whereas at 320 kPa, the fluorescent images showed an irreversible vascular damage. The study indicates that a potential mechanism for the transient decrease in perfusion may be related to blood coagulation. The results suggest that ultrasound and microbubbles can induce reversible and irreversible vascular

  20. Echo decorrelation imaging of ex vivo HIFU and bulk ultrasound ablation using image-treat arrays

    NASA Astrophysics Data System (ADS)

    Fosnight, Tyler R.; Hooi, Fong Ming; Colbert, Sadie B.; Keil, Ryan D.; Barthe, Peter G.; Mast, T. Douglas

    2017-03-01

    In this study, the ability of ultrasound echo decorrelation imaging to map and predict heat-induced cell death was tested using bulk ultrasound thermal ablation, high intensity focused ultrasound (HIFU) thermal ablation, and pulse-echo imaging of ex vivo liver tissue by a custom image-treat array. Tissue was sonicated at 5.0 MHz using either pulses of unfocused ultrasound (N=12) (7.5 s, 50.9-101.8 W/cm2 in situ spatial-peak, temporal-peak intensity) for bulk ablation or focused ultrasound (N=21) (1 s, 284-769 W/cm2 in situ spatial-peak, temporal-peak intensity and focus depth of 10 mm) for HIFU ablation. Echo decorrelation and integrated backscatter (IBS) maps were formed from radiofrequency pulse-echo images captured at 118 frames per second during 5.0 s rest periods, beginning 1.1 s after each sonication pulse. Tissue samples were frozen at -80˚C, sectioned, vitally stained, imaged, and semi-automatically segmented for receiver operating characteristic (ROC) analysis. ROC curves were constructed to assess prediction performance for echo decorrelation and IBS. Logarithmically scaled mean echo decorrelation in non-ablated and ablated tissue regions before and after electronic noise and motion correction were compared. Ablation prediction by echo decorrelation and IBS was significant for both focused and bulk ultrasound ablation. The log10-scaled mean echo decorrelation was significantly greater in regions of ablation for both HIFU and bulk ultrasound ablation. Echo decorrelation due to electronic noise and motion was significantly reduced by correction. These results suggest that ultrasound echo decorrelation imaging is a promising approach for real-time prediction of heat-induced cell death for guidance and monitoring of clinical thermal ablation, including radiofrequency ablation and HIFU.