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Blood biomarkers have significant potential applications in early detection and management of various diseases, including cancer. Most biomarkers are present in low concentrations in blood and are difficult to discriminate from noise. Furthermore, blood measurements of a biomarker do not provide information about the location(s) where it is produced. We hypothesize a previously undescribed strategy to increase the concentration of biomarkers in blood as well as localize the source of biomarker signal using ultrasound energy directly applied to tumor cells. We test and validate our hypothesis in cell culture experiments and mouse tumor xenograft models using the human colon cancer cell line LS174T, while measuring the biomarker carcinoembryonic antigen (CEA) before and after the use of ultrasound to liberate the biomarker from the tumor cells. The results demonstrate that the application of low-frequency ultrasound to tumor cells causes a significant release of tumor biomarker, which can be measured in the blood. Furthermore, we establish that this release is specific to the direct application of the ultrasound to the tumor, enabling a method for localization of biomarker production. This work shows that it is possible to use ultrasound to amplify and localize the source of CEA levels in blood of tumor-bearing mice and will allow for a previously undescribed way to determine the presence and localization of disease more accurately using a relatively simple and noninvasive strategy. cancer detection | CEA | mouse model | tumor biomarkers

Byline: Ludivine Chalumeau-Lemoine (1), Jean-Luc Baudel (1), Vincent Das (1), Lionel Arrive (2), Beatrice Noblinski (2), Bertrand Guidet (1,3), Georges Offenstadt (1,3), Eric Maury (1,3,4) Keywords: Bedside ultrasonography; Intensive care; Curriculum Abstract: Rationale and objectives To evaluate limited training of ICU physicians without knowledge of ultrasound in performing basic general ultrasonography. Design and setting A prospective, observational, study conducted in a 14-bed MICU. Patients Seventy-seven critically ill patients (38 females) aged 64 +- 16 years, with a SAPS II score of 47 +- 21, 49 of whom (64%) were receiving mechanical ventilation. Methods After 8.5 h of training comprising a 2.5 h didactic course that included essential views of normal and pathologic conditions and three hands-on sessions of 2 h each, one of eight ICU residents and the radiologist on duty performed the same examination in a blind manner. The questions addressed concerned the presence of pleural effusion, intra-abdominal effusion, acute cholecystitis, intrahepatic biliary duct dilation, obstructive uropathy, chronic renal disease, and deep venous thrombosis. Measurements and main results The answers to 129 questions were analyzed. The possible presence of pleural effusion, and arguments for the presence of urinary tract obstruction and chronic renal insufficiency, were the questions most frequently addressed. Residents answered 84.4% of the questions correctly [Kappa: 0.66, CI 95% (0.32--1.12)]. Most of the discrepancies concerned small non-drainable pleural or abdominal effusions. For questions with a potential therapeutic impact, residents answered 95% of the questions correctly [Kappa 0.86, CI 95% (0.75--1.04)]. Residents completed the examination in 37 +- 39 min compared with 296 +- 487 min for the radiologists (P = 0.004). Conclusions These results suggest that after brief focused training, intensive-care unit physicians without previous knowledge of ultrasonography can competently perform basic general ultrasonic examinations. Author Affiliation: (1) Medical Intensive Care Unit, Hopital Saint-Antoine, Assistance Publique-Hopitaux de Paris, Paris, France (2) Radiology Department, Hopital Saint-Antoine, Assistance Publique-Hopitaux de Paris, Paris, France (3) Universite Pierre et Marie Curie-Paris6, INSERM, UMR S-707, 75012, Paris, France (4) Service de Reanimation Medicale, Hopital Saint-Antoine, Assistance Publique-Hopitaux de Paris, 184 rue du Faubourg Saint-Antoine, 75571, Paris, France Article History: Registration Date: 28/05/2009 Received Date: 03/12/2008 Accepted Date: 27/04/2009 Online Date: 16/06/2009

The structural characteristics of a health3 tendon are related to the anisotropic speckle patterns observed in ultrasonic images. This speckle orientation is disrupted upon damage to the tendon structure as observed in patients with tendinopathy. Quantification of the structural appearance of tendon shows promise in creating a tool for diagnosing, prognosing, or measuring changes in tendon organization over time. The current work describes a first step taken towards this goal--classification of Achilles tendon images into tendinopathy anti control categories. Eight spatial frequency parameters were extracted from regions of interest on tendon images, filtered and classified using linear discriminant analysis. Resulting algorithms had better than 80% accuracy in categorizing tendon image kernels as tendinopathy or control. Tendon images categorized wrongly provided for an interesting clinical association between incorrect classification of tendinopathy kernels as control and the symptom and clinical time history based inclusion criteria. To assess intersession reliability of image acquisition, the first 10 subjects were imaged twice during separate sessions. Test-retest of repeated measures was excellent (r = 0.996, ICC (2,1) : 0.73 with one outlier) indicating a general consistency in imaging techniques. Index Terms--Classifier, image analysis, tendinopathy, tendon, ultrasound.

The article describes the application of minimum variance beamformer to medical ultrasound imaging which show a significant performance improvement in comparison to delay-and-sum (DAS).

The speckle reducing anisotropic diffusion filter can easily adapt the anisotropic diffusion filter to the various characteristics of the speckle noise present in the ultrasound images and also facilitate automatic processing of images. The properties of the numerical scheme associated with this filter are analyzed using a semi-explicit scheme.

The different methods of parallel beamforming are investigated that aims at eliminating the flaw and restoring the shift invariance property. The results have shown that straightforward parallel beamforming reduces the spatial shift invariance property of an ultrasound imaging system and the proposed method of using synthetic transmit beams have enabled higher acquisition rates without loss of image quality.

A research interface for an ultrasound system, which provides several basic capabilities normally unavailable on a clinical screener, is developed under a contract with the National Cancer Institute. The uses of the ultrasound research interface (URI) are illustrated on elastography, computed tomography and spatial compounding.

The impact of contrast agent infusion rates (IR) on thresholds for tissue injury is examined to ascertain the possible influence of IR for microbubble-enhanced ultrasound treatment. Results reveal that introduction of microbubble at IR up to a fixed level might prove successful in helping ultrasound therapy.

A multiparameter approach involving classification of breast masses in ultrasonic B-scan images is described and discussed.

Force-free images can provide diagnostic information unavailable in other image types.

Performance of an ultrasono-therapy transducer with contact detection is examined and reported.

Performance effects of a preclassification stage that subdivides tissue regions of interest (ROI) and classifies subregions based on scatterer structure types are examined and reported.

A procedure is proposed for imaging the relative tissue stiffness in medical ultrasound diagnostic equipment. The procedure makes use of tissue characteristics that respond differently to external vibration.

Centroid shift from signals backscattered from trabecular bone samples in vitro are measured and discussed.

An architecture of a hardware and software platform for ultrasonic diagnosis is described and discussed.

Cell membrane damage induced by diagnostic ultrasound exposure with a contrast agent is described and discussed. Its relation to the display of stimulated acoustical emissions in Doppler images is examined.

An extrapolation technique for strengthening the lateral resolution of pulse-echo imaging systems is described and discussed.

Research describing the attenuation properties of human calcaneus at high frequencies is presented. The results of the study indicate that ultrasonic attenuation exhibits a linear dependence on frequency.

Byline: D. Lichtenstein (1), J.-S. Hulot (1), A. Rabiller (1), I. Tostivint (1), G. Meziere (2) Keywords: Key words Thoracentesis; Pleural effusion; Ultrasound diagnosis; Thorax; ultrasound diagnosis; Lung; ultrasound diagnosis; Intensive care unit Abstract: Objective: Thoracentesis in a ventilated patient is rarely performed because of the risk of pneumothorax. We have evaluated the safety of this procedure when aided by ultrasound. Design: Prospective study. Setting: Medical intensive care unit, university-affiliated hospital. Patients: 45 procedures were performed in 40 consecutive patients with ultrasound signs of pleural effusion, all mechanically ventilated. Interventions: Pleural effusion was defined on ultrasound as a collection of fluid between parietal and visceral pleura leading to variations in interpleural distance during breathing. When the interpleural distance was aY= 15 mm and visible over three intercostal spaces, a needle (16 or 21 G) was inserted after ultrasound localization in a patient in either dorsal or lateral decubitus. Results: No complication occurred in the 45 thoracenteses. Fluid was obtained in 44 of 45 procedures, thus confirming the diagnosis of pleural effusion. The procedure was immediate (less than 10 s) in 40 of 45 cases. It was easy (i. e., keeping the patient supine) in 22 of 45 procedures. In 44 cases where fluid was obtained, only 27 bedside radiographs revealed signs of effusion, whereas 17 showed absence of a visible effusion. Ultrasound thus appeared more efficient than bedside X-ray in detecting pleural effusion. Conclusions: If basic rules are followed, ultrasound localization makes thoracentesis a safe, easy and simple procedure in patients on mechanical ventilation. Author Affiliation: (1) Service de Reanimation Medicale, Hopital Ambroise-Pare, 9 avenue Charles-de-Gaulle, F-92 100 Boulogne (Paris), France Tel. + 33(1)49 09 56 01 Fax + 33(1)49 09 58 92, FR (2) Service de Reanimation Polyvalente, Centre Hospitalier General, Saint-Cloud (Paris), France, FR Article note: Received: 9 November 1998 Final revision received: 24 April 1999 Accepted: 17 May 1999

Single-photon emission computed tomography (SPECT) and ultrasonic diffraction tomography (UDT) are tomographic imaging modalities that are based upon entirely different physical processes. In SPECT, from the measured intensity of the electromagnetic wave (i.e., the gamma-ray), one seeks to determine the distribution of the gamma-ray emitter within an object. In UDT, from the measured scattered fields (i.e., the scattered ultrasonic wave), one determines the refractive index distribution. However, in this work, we demonstrate that the mathematics describing image reconstruction and the statistical analysis of image-noise properties are virtually identical for SPECT and UDT. We also conducted computer-simulation studies, which quantitatively corroborated our theoretical analysis.