GE Healthcare has received the FDA OK for its Optima CT660 computed tomography (CT) system. The CT660, which is already available in Europe, Latin America and Asia, distinguishes itself by its compact footprint combined with a modular design and low dose imaging. In addition, it is also one of the most energy efficient CT scanners available and has an “environmental design” that eases refurbishment and end-of-life recycling. The scanner itself is scalable from 32 to 128 slices through purchasable options and features automatic table positioning and a color 12-inch integrated gantry display monitor. Read more »
*This blog post was originally published at Medgadget*
Duke University scientists have been successfully testing a new laser system they developed to identify cancerous skin moles. Two lasers in the system are used to identify the presence of eumelanin in biopsy slices and a future version of the device may work directly without having to sample the mole. According to an article in Science Translational Medicine, “the ratio of eumelanin to pheomelanin captured all investigated melanomas but excluded three-quarters of dysplastic nevi and all benign dermal nevi.” From the press release:
The tool probes skin cells using two lasers to pump small amounts of energy, less than that of a laser pointer, into a suspicious mole. Scientists analyze the way the energy redistributes in the skin cells to pinpoint the microscopic locations of different skin pigments.
The Duke team imaged 42 skin slices with the new tool. The images show that melanomas tend to have more eumelanin, a kind of skin pigment, than healthy tissue. Using the amount of eumelanin as a diagnostic criterion, the team used the tool to correctly identify all eleven melanoma samples in the study.
The technique will be further tested using thousands of archived skin slices. Studying old samples will verify whether the new technique can identify changes in moles that eventually did become cancerous.
Malignant melanoma under the new laser light. Clear deposits of eumelanin (red) appear in unhealthy tissue.
Press release: Lasers ID Deadly Skin Cancer Better than Doctors …
Abstract in Science Translational Medicine: Pump-Probe Imaging Differentiates Melanoma from Melanocytic Nevi
Flashback: Diagnosing Skin Cancers with Light, Not Scalpels
*This blog post was originally published at Medgadget*
There’s a new study out on mammography with important implications for breast cancer screening. The main result is that when radiologists review more mammograms per year, the rate of false positives declines.
The stated purpose of the research*, published in the journal Radiology, was to see how radiologists’ interpretive volume — essentially the number of mammograms read per year — affects their performance in breast cancer screening. The investigators collected data from six registries participating in the NCI’s Breast Cancer Surveillance Consortium, involving 120 radiologists who interpreted 783,965 screening mammograms from 2002 to 2006. So it was a big study, at least in terms of the number of images and outcomes assessed.
First — and before reaching any conclusions — the variance among seasoned radiologists’ everyday experience reading mammograms is striking. From the paper:
…We studied 120 radiologists with a median age of 54 years (range, 37–74 years); most worked full time (75%), had 20 or more years of experience (53%), and had no fellowship training in breast imaging (92%). Time spent in breast imaging varied, with 26% of radiologists working less than 20% and 33% working 80%–100% of their time in breast imaging. Most (61%) interpreted 1000–2999 mammograms annually, with 9% interpreting 5000 or more mammograms.
So they’re looking at a diverse bunch of radiologists reading mammograms, as young as 37 and as old as 74, most with no extra training in the subspecialty. The fraction of work effort spent on breast imaging –presumably mammography, sonos and MRIs — ranged from a quarter of the group (26 percent) who spend less than a fifth of their time on it and a third (33 percent) who spend almost all of their time on breast imaging studies. Read more »
*This blog post was originally published at Medical Lessons*
This was the Guest Blog at Scientific American on February 16th, 2011.
New wave of MRI-safe pacemakers set to ship to hospitals
This week Medtronic will begin shipping to hospitals in the United States the first pacemaker approved by the FDA as safe for most MRI scans. For consumers, it is a significant step in what is expected to be a wave of new MRI-compatible implanted cardiac devices.
But this is an example of one technology chasing another and the one being chased, the MRI scanner, is changing and is a step ahead of the new line of pacemakers. The pacemaker approved for U.S. distribution is Medtronic’s first-generation pacemaker with certain limitations, while its second-generation MRI-compatible pacemaker is already in use in Europe where approval for medical devices is not as demanding as it is in the U.S. So let’s check out what this is all about — what it means now for current and future heart patients and where it may be headed.
We are all born with a natural pacemaker that directs our heart to beat 60 to 100 times a minute at rest. The pacemaker is a little mass of muscle fibers the size and shape of an almond known medically as the sinoatrial node located in the right atrium, one of four chambers of the heart. The natural pacemaker can last a lifetime. Or it can become defective. And even if it keeps working normally, some point may not function well along the electrical pathway from the pacemaker to the heart’s ventricles which contract to force blood out to the body.
Millions of people in the world whose hearts beat too fast, too slow, or out of sync because their own pacemaker is not able to do the job right, follow their doctors’ recommendation to get an artificial pacemaker connected to their heart to direct its beating. The battery-run pacemaker in a titanium or titanium alloy case the size of a small cell phone, (why can’t it be the size of an almond?) is implanted in the upper left chest, just under the skin, with one or two insulated wire leads connecting to the heart. It can be programmed to run 24/7 or to only operate when the heart reaches a certain state of irregular beating. Read more »
*This blog post was originally published at HeartSense*
Federal law generally prohibits physicians from referring their own patients to a diagnostic facility in which they have an ownership issue — a practice called “self-referral” — unless the facility is located in their own practice. This exemption exists to allow patients with access to a laboratory test, X-ray, or other imaging test at the same time and place as when patients are seeing their physician for an office visit. Less inconvenience and speeder diagnosis and treatment — what could be wrong with that?
Much, say the critics, if it leads to overutilization and higher costs and doesn’t really represent a convenience to patients. This is the gist of two studies by staff employed by the American College of Radiology, published in the December issue of Health Affairs.
One study analyzes Medicare claims data and concludes that patients aren’t really getting “one-stop-shopping” convenience when their physician refers them to an imaging facility that qualifies for the “in-office” exemption.
“Specifically, same-day imaging was the exception, other than for the most straightforward types of X-rays. Overall, less than one-fourth of imaging other than these types of X-rays was accompanied by a same-day office visit. The fraction for high-tech imaging was even lower — approximately 15 percent.” Read more »
*This blog post was originally published at The ACP Advocate Blog by Bob Doherty*