- Category: ICUS Weekly News Monitors
1. EFSUMB Newsletter, Nov, 2015, CEUS for focal liver lesions, WEBINAR 18 DECEMBER 2015
2. Space Daily, Dec 9, 2015, Popping microbubbles help focus light inside the body
By Staff Writers
3. La radiologia medica, Mar 31, 2015 (online), Accuracy of contrast‑enhanced ultrasound (CEUS) in the identification and characterization of traumatic solid organ lesions in children: a retrospective comparison with baseline US and CE‑MDCT Authors: Guendalina Menichini, et al
CEUS for focal liver lesions
WEBINAR 18 DECEMBER 2015
This webinar will be offered free of charge.
Participation at the webinar is limited to a maximum of 100 participants. Online registration will be closed upon reaching the maximum numbers of participants. Early registration is recommended and EFSUMB looks forward to your understanding technically no additional places can be offered once the limit is reached. Please regsiter for this event using the form above.
EFSUMB Webinar is provided using Gotomeeting online software.
REGISTER HERE <http://efsumb.bmetrack.com/c/l?u=5ADD4C6&e=849975&c=6FA07&t=0&l=11EFCD64&email=esQyiGFBwehiXGiJQJ9I4IUU0UGuXuz4NyIeD9VsXLU%3D&seq=2>
Event Organisers & Speakers:
Vito Cantisani - Chair
Dr. PhD, Vito Cantisani is a staff member and Instructor in Radiology at Policlinico Umberto I, Univ. Sapienza of Rome and qualified as Ass. Prof. in Radiology at ASN in 2014.
Prof Dr Christoph F Dietrich, EFSUMB Past President - Presenter
Presentation: Characterisation of malignant liver tumours using CEUS
Location: Bad Mergentheim
Prof Dr Odd Helge Gilja, EFSUMB President - Presenter
Presentation: Characterisation of Benign liver tumours using CEUS
Professor Dr Fabio Piscaglia - Presenter
Presentation: Roles of CEUS for HCC
Dec 9, 2015
Popping microbubbles help focus light inside the body
By Staff Writers
Medical grade albumin encapsulated gas microspheres are imaged with a 20X microscope. Image courtesy Haowen Ruan, Mooseok Jang, and Changhuei Yang/Caltech. For a larger version of this image please go here.
A new technique developed at Caltech that uses gas-filled microbubbles for focusing light inside tissue could one day provide doctors with a minimally invasive way of destroying tumors with lasers, and lead to improved diagnostic medical imaging.
The primary challenge with focusing light inside the body is that biological tissue is optically opaque. Unlike transparent glass, the cells and proteins that make up tissue scatter and absorb light.
"Our tissues behave very much like dense fog as far as light is concerned," says Changhuei Yang, professor of electrical engineering, bioengineering, and medical engineering. "Just like we cannot focus a car's headlight through fog, scientists have always had difficulty focusing light through tissues."
To get around this problem, Yang and his team turned to microbubbles, commonly used in medicine to enhance contrast in ultrasound imaging.
The gas-filled microbubbles are encapsulated by thin protein shells and have an acoustic refractive index - a property that affects how sound waves propagate through a medium - different from that of living tissue. As a result, they respond differently to sound waves.
"You can use ultrasound to make microbubbles rapidly contract and expand, and this vibration helps distinguish them from surrounding tissue because it causes them to reflect sound waves more effectively than biological tissue," says Haowen Ruan, a postdoctoral scholar in Yang's lab.
In addition, the optical refractive index of microbubbles is not the same as that of biological tissue. The optical refractive index is a measure of how much light rays bend when transitioning from one medium (a liquid, for example) to another (a gas).
Yang, Ruan, and graduate student Mooseok Jang developed a novel technique called time-reversed ultrasound microbubble encoded (TRUME) optical focusing that utilizes the mismatch between the acoustic and optical refractive indexes of microbubbles and tissue to focus light inside the body. First, microbubbles injected into tissue are ruptured with ultrasound waves.
By measuring the difference in light transmission before and after such an event, the Caltech researchers can modify the wavefront of a laser beam so that it is focuses on the original locations of the microbubbles. The result, Yang explains, "is as if you're searching for someone in a dark field, and suddenly the person lets off a flare. For a brief moment, the person is illuminated and you can home in on their location."
In a new study, published online November 24, 2015, in the journal Nature Communications, the team showed that their TRUME technique could be used as an effective "guidestar" to focus laser beams on specific locations in a biological tissue. A single, well-placed microbubble was enough to successfully focus the laser; multiple popping bubbles located within the general vicinity of a target functioned as a map for the light.
"Each popping event serves as a road map for the twisting light trajectories through the tissue," Yang says.
"We can use that road map to shape light in such a way that it will converge where the bubbles burst."
If TRUME is shown to work effectively inside living tissue - without, for example, any negative effects from the bursting microbubbles - it could enable a range of research and medical applications. For example, by combining the microbubbles with an antibody probe engineered to seek out biomarkers associated with cancer, doctors could target and then destroy tumors deep inside the body or detect malignant growths much sooner.
"Ultrasound and X-ray techniques can only detect cancer after it forms a mass," Yang says. "But with optical focusing, you could catch cancerous cells while they are undergoing biochemical changes but before they undergo morphological changes."
The technique could take the place of other of diagnostic screening methods. For instance, it could be used to measure the concentrations of a protein called bilirubin in infants to determine their risk for jaundice. "Currently, this procedure requires a blood draw, but with TRUME, we could shine a light into an infant's body and look for the unique absorption signature of the bilirubin molecule," Ruan says.
In combination with existing techniques that allow scientists to activate individual neurons in lab animals using light, TRUME could help neuroscientists better understand how the brain works. "Currently, neuroscientists are confined to superficial layers of the brain," Yang says. "But our method of optical focusing could allow for a minimally invasive way of probing deeper regions of the brain."
The paper is entitled "Optical focusing inside scattering media with time-reversed ultrasound
microbubble encoded (TRUME) light."
La radiologia medica
Mar 31, 2015 (online)
Radiol med (2015) 120:989–1001
Accuracy of contrast‑enhanced ultrasound (CEUS) in the identification and characterization of traumatic solid organ lesions in children: a retrospective comparison with baseline
US and CE‑MDCT
Authors: Guendalina Menichini1 · Barbara Sessa1 · Margherita Trinci1 · Michele Galluzzo1 ·
* Vittorio Miele
1 Department of Emergency Radiology, S. Camillo Hospital,
Circonvallazione Gianicolense, 87, 00152 Rome, Italy
Localized low-energy abdominal trauma is very frequent in the pediatric population. The findings of several studies have shown that ultrasonography (US) can represent a useful and cost-effective tool in the evaluation of blunt abdominal trauma both in adults and children.
However, many parenchymal injuries are not correctly visualized at baseline US examination. The introduction of specific US contrast agents contrast-enhanced ultrasound (CEUS) has enabled a better identification of traumatic organ injuries. The correct use of CEUS could therefore identify and select the children who need further diagnosticinvestigation computed tomography (CT), avoiding unnecessary radiation and iodinated contrast medium exposure. The purpose of our study was to assess the sensibility and feasibility of CEUS in the assessment of low-energy abdominal trauma compared to baseline US in pediatric patients, using contrast-enhanced MDCT as the reference standard.
Materials and methods
We retrospectively reviewed 73 children (51 M and 22 F; mean age 8.7 ± 2.8 years) who presented in our Emergency Department between October 2012 and October 2013, with history of minor abdominal trauma according to the Abbreviated Injury Scale and who
underwent US, CEUS, and CE-MDCT. Inclusion criteria were: male or female, aged 0–16, hemodynamically stable patients with a history of minor blunt abdominal trauma.
Exclusion criteria were adulthood, hemodynamical instability, history of major trauma. Sensitivity, specificity, PPV, NPV, and accuracy were determined for US and CEUS compared to MDCT.
6/73 patients were negative at US, CEUS, and MDCT for the presence of organ injuries. In the remaining 67 patients, US depicted 26/67 parenchymal lesions. CEUS identified 67/67 patients (67/67) with parenchymal lesions: 21 lesions of the liver (28.8 %), 26 lesions of the spleen (35.6 %), 7 lesions of right kidney (9.6 %), 13 lesions of left kidney. MDCT confirmed all parenchymal
lesions (67/67). Thus, the diagnostic performance of CEUS was better than that of US, as sensitivity, specificity, PPV, NPV, and accuracy were 100, 100, 100, 100, and 100 % for CEUS and 38.8, 100, 100, 12.8, and 44 % for US. In some patients CEUS identified also prognostic factors as parenchymal active bleeding in 8 cases, partial devascularization in 1 case; no cases of vascular bleeding, no cases of urinoma. MDCT confirmed all parenchymal lesions. Parenchymal
active bleeding was identified in 16 cases, vascular bleeding in 2 cases, urinoma in 2 cases, partial devascularization in 1 case.
CEUS is more sensitive and accurate than baseline US and almost as sensitive as CT in the identification and characterization of solid organs lesions in blunt abdominal trauma. CT is more sensitive and accurate than CEUS in identifying prognostic indicators, as active bleeding
and urinoma. CEUS should be considered as a useful tool in the assessment and monitoring of blunt abdominal trauma in children.