Posts Tagged ‘camera’

Showcase of latest advances in medical imaging for revolutionary proton therapy cancer treatment

The University of Lincoln’s Professor Nigel Allinson MBE will deliver the keynote talk at the tenth International Conference on Position Sensitive Detectors. The conference, which takes place from 7th to 12th September 2014, features the latest developments in this field from leading researchers around the world.

Professor Allinson leads the pioneering PRaVDA (Proton Radiotherapy Verification and Dosimetry Applications) project. He and his multinational team are developing one of the most complex medical instruments ever imagined to improve the delivery of proton beam therapy in the treatment of cancer.

Proton beam therapy is a type of particle therapy that uses a beam of protons to irradiate diseased tissue. Proton beam therapy has the ability to deliver high doses of radiation directly to a tumour site with very little radiation being absorbed into healthy tissue.

PRaVDA, funded by a £1.6 million grant from the Wellcome Trust, will provide a unique instrument capable of producing real-time 3D images — a proton CT — of a patient, drawing data from the same protons used in the treatment itself.

The patent-pending technology, which uses detectors at the heart of the Large Hadron Collider at CERN alongside world-first radiation-hard CMOS imagers, will reduce dose uncertainties from several centimetres to just a few millimetres.

This promises to make proton therapy an option for thousands more cancer patients by reducing the risks of healthy tissue being damaged during treatment, particularly in vulnerable parts of the body such as the brain, eye and spinal cord.

Professor Allinson, who will also be talking about his research to prospective students at the University of Lincoln open day on Saturday, 20th September, said: “PRaVDA will ensure more difficult tumours will become treatable and more patients overall will be able to receive this revolutionary treatment.”

Other members of the PRaVDA team will also present their work at the conference, describing in more detail the high-speed tracking technology that can record the paths of individual protons as they enter and leave a patient. The team will also outline how they make and test the new detectors in PRaVDA to ensure they are resistant to the high levels of radiation present in proton therapy.

The researchers have just taken delivery of some of the technology which will lie at the heart of the system: two state-of-the-art custom integrated circuits (chips) which will underpin PRaVDA’s imaging capabilities.

One device is a radiation-hard CMOS imager, measuring 10cm x 6.5cm, and producing more than 1,500 images per second. The camera chip in a mainstream smartphone is a CMOS imager but PRaVDA’s chip is over 300 times larger and operates 50 times faster — the fastest large-area CMOS imager ever made. The completed PRaVDA instrument will contain 48 of these imagers, giving a total imaging area of nearly two-and-a-half square metres.

The second device is the read-out chip for the very high-speed strip detectors that track the passage of individual protons as they enter and exit a patient. This chip, called Rhea, converts the electric charge created by a passing proton into a digital signal with additional logic to provide accurate timing (to one hundredth of one millionth of a second) while preventing erroneous signals being recorded.

The strip detectors were designed at the University of Liverpool by the same team that developed detectors for the Large Hadron Collider at CERN, which led to the discovery of the Higgs Boson in 2013. Nearly 200 Rheas are used in the complete PRaVDA system.

PRaVDA’s industrial partner, ISDI LTD, designed both devices. Their testing was undertaken by the project’s second industrial partner, aSpect Systems GmbH, in Dresden, Germany.

source : http://www.sciencedaily.com/releases/2014/09/140904121147.htm

Special camera detects tumors

Tumor removal surgeries pose a great challenge even to skillful and experienced surgeons. For one thing, tumor margins are blending into healthy tissue and are difficult to differentiate. For another, distributed domains of cancer and pre-malignancies are difficult to recognize. Up to now, doctors depend exclusively upon their trained eyes when excising pieces of tumors. In future, a new special camera system can help visualize during operation even the smallest, easy-to-overlook malignant pieces of tumor and thereby support the surgeons during complicated interventions.

The trick: the camera can display fluorescent molecules that "paint" the cancer tissue. These are injected into the patients blood circulation prior to the operation and selectively attach onto the tumor during their trip through the body. If the corresponding area is then illuminated with a specific wavelength, fluorescence is emitted and the malignant tissue glows green, blue, red, or any other color, depending on the injected dye, while the healthy tissue appears the same. In this way, the surgeon can see clasters of tumors cells that cannot be recognized by the naked eye.

New system reveals several dyes simultaneously

Researchers at the Fraunhofer Project Group for Automation in Medicine and Biotechnology (PAMB), which belongs to the Fraunhofer Institute for Manufacturing Engineering and Auto- mation (IPA), have developed a new surgical aid, a multispectral fluorescence camera system. In the future, this special camera will integrate into various medical imaging systems such as, surgical microscopes and endoscopes, etc. The scientists from Mannheim, Germany, will make the debut of a prototype of this high-tech system at the Medica Trade Fair in Düsseldorf in the joint Fraunhofer booth (Halle 10, Booth F05) between 20-23 November. The novel aspect about this camera: it can display several fluorescent dyes and the reflectance image simultaneously in real time — systems available until now have not been able to achieve this. The advantage: arteries and delicate nerves that must not be injured during an intervention can likewise be colored with dye. They too can then be detected with the new camera, since they are set apart from their surroundings.

"The visibility of the dye to the camera depends in large part on the selection of the correct set of fluorescence filters. The filter separates the incident excitation wave- lengths from the fluorescing wavelengths so that the diseased tissue is also set apart from its surroundings, even at very low light intensities," says Nikolas Dimitriadis, a scientist at PAMB. The researchers and their colleague require only one camera and one set of filters for their photographs, which can present up to four dyes at the same time. Software developed in-house analyses and processes the images in seconds and presents it continuously on a monitor during surgery. The information from the fluores- cent image is superposed on the normal color image. "The operator receives significantly more accurate information. Millimeter-sized tumor remnants or metastases that a surgeon would otherwise possibly overlook are recognizable in detail on the monitor. Patients operated under fluorescent light have improved chances of survival," says Dr. Nikolas Dimitriadis, head of the Biomedical Optics Group at PAMB.

In order to be able to employ the multispectral fluorescence camera system as adapt- ably as possible, it can be converted to other combinations of dyes. "One preparation that is already available to make tumors visible is 5-amino levulinic acid (5-ALA). Physicians employ this especially for glioblastomas — one of the most frequent malig- nant brain tumors in adults," explains Dimitriadis. 5-ALA leads to an accumulation of a red dye in the tumor and can likewise be detected with the camera. The multispectral fluorescence imaging system should have passed testing for use with humans as soon as next year. The first clinical tests with patients suffering from glioblastomas are planned for 2014.

source : http://www.sciencedaily.com/releases/2013/11/131107103527.htm