TINY CONSTRAINTS IN HEART BLOOD FLOW: A BETTER SIGN OF BLOOD VESSEL NARROWING AND EARLY CORONARY ARTERY DISEASE
- Major study of perfusion imaging under way to assess value of alternative diagnostic methods
February 2, 2010-Cardiologists and heart imaging specialists at 15 medical centers in eight countries, and led by researchers at Johns Hopkins, have enrolled the first dozen patients in a year-long investigation to learn whether the subtle squeezing of blood flow through the inner layers of the heart is better than traditional SPECT nuclear imaging tests and other diagnostic radiology procedures for accurately tracking the earliest signs of coronary artery clogs.
Each year, nearly 800,000 American men and women with coronary artery disease suffer a heart attack, resulting in more than 150,000 deaths.
The latest international study of so-called CT perfusion imaging will involve the participation of some 400 men and women identified as being at higher risk of coronary artery disease because they have had symptoms of the illness, such as shortness of breath, chest pain or fatigue. All qualify for a more detailed inspection of their heart’s blood vessels by cardiac catheterization, an invasive procedure in which a thin plastic tube is directly inserted into the heart’s blood vessels to detect blockages and help widen each artery as needed.
“Our study goal is to figure out how well various imaging tests measure the degree of blockage or narrowing in any particular artery and therefore which is more useful in predicting patients who need catheterization or angioplasty, or bypass surgery,” says cardiologist and senior study investigator João Lima, M.D. “Some patients would do just as well or better with drug therapy to maintain a healthy blood flow to the heart, but we need to better sort out who they are with more accuracy.”
Lima says that as many as one-fifth of the 1.3 million cardiac catheterizations performed each year nationwide show no blockages.
In addition to having a standard SPECT imaging test, in which radioactive chemicals are injected into the body to produce 3-D images of the blood vessels, all study participants will undergo before catheterization another test to map out the blood vessels and any potential blockages, a CT angiogram (CTA), plus a CT perfusion (CTP) imaging test to gauge any changes in the volume of blood flow.
Key to performing both CTA and CTP is use of the 320 computed tomography scanner, the most advanced technology available to image the heart and its surrounding blood vessels. The device was first installed in North America at Johns Hopkins in 2007 and can produce three-D images of blood vessels no bigger than the average width of a toothpick (1.5 millimeters). Results from both 320-CT tests will be compared to those from SPECT and what is found by cardiac catheterization.
“Perfusion imaging is a simple and easy test for patients to undergo,” says Lima, who adds that the whole procedure usually takes less than 20 minutes to set up and perform. Cardiac catheterization, which also checks for heart vessel blockages, takes longer, between 30 minutes and 45 minutes to perform, and requires several hours for recovery. Potential complications from the invasive procedure, although rare, include heart attack, stroke and death.
“If we can more easily examine patients, then we can reduce the amount of time needed in hospital and, we hope, reduce the number of invasive procedures, which are more inconvenient and open to greater risk to patients from complications,” says Lima, a professor of medicine and radiology at the Johns Hopkins University School of Medicine and its Heart and Vascular Institute.
More than a quarter-million Americans undergo coronary bypass surgery each year, and another 1.2 million people undergo angioplasty, a procedure much like catheterization that forcibly opens narrowed arteries.
Lead study investigator and cardiologist Richard George, M.D., part of the Johns Hopkins team that developed special computer software to accurately measure the speed of blood flowing through the heart’s arteries and muscle, says the 320-CT is fast and exposes patients to far less radiation.
George, an assistant professor at Hopkins where he also serves as director of its CT Perfusion Laboratory, says a CTP takes three seconds or less of actual scanning and, if done correctly, involves an average radiation exposure of about 8 millisieverts. A SPECT test, he says, averages between 10 millisieverts and 26 millisieverts, and cardiac catheterization ranges between 2 millisieverts and 10 millisieverts. The 320-CT scanning device has at least five times the speed and power of the 64-CT scanners in widespread use elsewhere.
The scanner’s software compares ratios of brightly dyed blood flows between the innermost and outermost layers of heart muscle, where the effects of arterial narrowing first appear.
As part of CTP imaging, each patient is injected with a chemical dye containing iodine, known to light up on screen when struck by the scanner’s X-rays. Lower concentrations of iodine will show up as darker regions, indicating constrained and reduced blood flow, the underlying cause of chest pain, than brighter regions where blood flow is more uniform and free flowing.
To enhance the image, blood flow to the heart is sped up through chemical injections of adenosine, which causes the blood-pumping organ to beat faster.
Previous research by the team among 60 patients with suspected coronary artery disease showed that using dual testing with CTA and CTP had almost the same statistical predictive values as SPECT, prompting the team’s latest investigation to see if the dual tests were as clinically useful as SPECT.
George cautions that CT scans are not a substitute for catheterization, but are “an alternative diagnostic tool” physicians can use to “get a real picture” of the extent of coronary blockages and their effects on blood flow, especially when physicians need both sets of information to make treatment decisions.
The CT device being used in the study is an Aquilion One, a 320 detector row CT scanner manufactured by Toshiba.
Toshiba also provided funding support for the study, called CORE-320, short for Coronary Artery Evaluation Using 320-row Multidetector Computed Tomography.
The CORE-320 study follows another imaging study, called CORE-64, which showed that 64-CT was almost as good as cardiac catheterizations in predicting which patients with suspected coronary disease actually had coronary blockages.
In addition to Lima and George, other Hopkins researchers involved in this study are Armin Arbab-Zadeh, M.D.; Julie Miller, M.D.; Jeffrey Brinker, M.D.; David Bluemke, M.D.; Andrea Vavere, M.S.; John Texter, P.A.; Albert Lardo, Ph.D.; Eric Bukata; and Christopher Cox, Ph.D.
Other CORE-320 participating sites include in the United States, Beth Israel Deaconess Medical Center and the Brigham and Women’s Hospital, both in Boston, plus the U.S. National Heart, Lung and Blood Institute, a member of the National Institutes of Health, in Bethesda, Md.; in Canada, Toronto General Hospital, part of the University Health Network; in Denmark, the Rigshospitalet at the University of Copenhagen; in Germany, Charité Universitätsmedizin in Berlin; in the Netherlands, Leiden University Medical Center; in Brazil, the Heart Institute of the Clinical Hospital of Sao Paulo University’s Medical College in Botucatu, and the Hospital Israelita Albert Einstein in Sao Paulo; in Singapore, Medi-Rad Associates Radiologic Clinic at Mount Elizabeth Medical Centre, and the National Heart Centre Singapore; and in Japan, Iwate Medical University in Morioka, Mie University School of Medicine in Tsu City, and Keio University’s School of Medicine in Tokyo.
RSNA: Radiology full of malpractice minefields
Written by Mike Bassett Friday, December 04 2009
CHICAGO--Radiologists who are caring, competent, comprehensive, consistent and credible should be able to practice their livelihood without too much fear of being sued for malpractice, according to a presentation "Minefields in Radiology," delivered Thursday at the Radiological Society of North American (RSNA) conference.
Robert Albert Schmidt, a radiologist at the University of Chicago Medical Center, referred to a quote from Walt Kelly’s famous comic strip “Pogo” to describe the situation radiologists sometimes find themselves in when it comes malpractice—“We have met the enemy and them is us.”
For example, Schmidt pointed out that few radiologists have read the American College of Radiology standards. “So if you don’t know what’s there, guess who reads these things,” he said. “Lawyers—lawyers read these things all the time. So you may think, ‘I don’t agree with this, this isn’t the way I practice.’ But the fact is you need to know what’s going on there because you’re vulnerable to it. They read it.”
The failure of radiologists to take steps like this to protect themselves from malpractice suits occurs despite the fact a large percentage of these radiologists believe they are extremely vulnerable to these suits.
For example, surveys taken in 2002 and 2006 found that radiologists' mean estimate of the probability of being sued for malpractice in the next five years was 41 percent in 2002 and 35 percent in 2006. The actual number of claims was 8 percent in 2002 and 10 percent in 2006, which means, Schmidt said, that the fear of being sued for malpractice is exaggerated.
Yet, radiology remains the speciality most likely to be sued. According to figures supplied by Schmidt, the specialty represented 11 percent of the malpractice cases in 1990, 24 percent in 1995 and 33 percent in 2002.
Why are lawsuits rising? Schmidt -- who was speaking specifically about mammography malpractice during his part of the presentation -- says that one of the problems is that the public has unrealistic expectations, “some of which we’ve actually fostered by our own promotion of mammograms. It’s a two-edged sword. We want people to have mammograms and we promote them. But on the other hand, they’re not perfect.” Schmidt added that factors such as pressures to cut costs and the larger volumes of cases being handled are also reason for the increase in malpractice suits.
Many of these cases involve symptomatic patients with palpable lesions or some other complaint, said Schmidt. But one of the major problems in many of these situations, he said, was a failure to do an ultrasound. “The biggest thing I can tell you is that if you have a person with a complaint, do an ultrasound.”
One-third of plaintiffs in mammography malpractice cases are under the age of 40, said Schmidt, and the median age of a claimant is 44. In addition, patients in 59 percent of these cases found lesions. So a typical profile of a patient suing is someone who is “young and has a complaint,” said Schmidt.
To protect their patients and to protect themselves against lawsuits, Schmidt said radiologists should always:
- Follow up with other consultants;
- Recommend a tissue diagnosis if a patient has a palpable mass with a negative breast image evaluatio;
- Reinterpret a technically poor mammogram;
- Recommend another mammogram with added views or other imaging as appropriate if the original mammogram is equivocal;
- Be sure everything is accurately performed and documented;
- Compare to previous studies;
- Report results promptly;
- Tell a patient to consult with her primary physician if there is an abnormal result;
Last updated on December 4, 2009 at 2:48 pm EST
SNMTS Members Can Now Transfer CE Credits to ARRT Electronically
(July 9, 2009) — Reporting continuing education (CE) credits to the American Registry of Radiologic Technologists (ARRT) just got easier for members of the Society of Nuclear Medicine Technologist Section (SNMTS) who opt-in on the SNM website.
Now they, along with members of the American Society of Radiologic Technologists (ASRT), can have their credits automatically transferred to ARRT. ASRT members have enjoyed this service since 2003.
"We’re excited to be offering this option to another group of technologists," said Jerry B. Reid, Ph.D., ARRT executive director. "ARRT is committed to quality customer service, and this is yet another way to streamline and simplify the CE reporting process."
R.T.s who choose to complete their ARRT renewal of registration online will be able to see the number of CE credits that ASRT and/or SNMTS have reported. Those who have met the requirements for their biennium will be able to proceed with their renewal, and those with partial credits can simply add in the remaining credits they have completed.
The American Registry of Radiologic Technologists promotes high standards of patient care by recognizing individuals qualified in medical imaging, interventional procedures, and radiation therapy. Headquartered in St. Paul, Minnesota, ARRT evaluates, certifies, and annually registers more than a quarter-of-a-million radiologic technologists across the United States
News flash: UTMB Interventional Radiology involved in clinical trials
Delcath Systems, Inc. (NASDAQ: DCTH) announced today that the University of Texas Medical Branch at Galveston (UTMB), part of the University of Texas System, has joined Delcath's Phase III clinical trial for the treatment of inoperable metastatic melanoma in the liver using the Company's Percutaneous Hepatic Perfusion (PHP) System for the isolated, high-dose delivery of the anti-cancer agent melphalan. UTMB is the sixth center in this multi-center study testing the Delcath System.
Delcath and UTMB have entered into a clinical research agreement to conduct the Phase III National Cancer Institute (NCI) led study. Orhan S. Ozkan, MD, Associate Professor of Radiology and Director of Vascular and Interventional Radiology, will serve as the Principal Investigator of the study. On joining this study, Dr. Ozkan commented, "We are excited about being a part of this clinical trial and being the first center to offer this treatment modality to patients in this region of the US. This treatment offers tremendous promise for patients suffering from metastatic melanoma in the liver, and we are pleased to be able to offer this option to our patients
Interventional radiology: From sidelines to mainstream for patients
Society of Interventional Radiology hails ACR 10-year extension of resolution in support of clinical patient management by vascular and interventional radiologists as plus for patient care
FAIRFAX, Va. (May 12, 2009)—The Society of Interventional Radiology hailed the extension of an American College of Radiology resolution in support of clinical patient management by vascular and interventional radiologists as an important reminder of the critical contribution these minimally invasive specialists bring to quality patient health care.
"Passage of ACR's Resolution 22 is a continued endorsement of interventional radiology's unique contribution of supporting innumerable clinical services while providing direct care," said SIR President Brian F. Stainken, M.D., FSIR. "Interventional radiologists provide patients with the least invasive and most advanced treatment options for a wide variety of medical conditions, offering less risk, less pain and less recovery time when compared to open surgery," noted Stainken. ACR endorsed interventional radiology's clinical patient-centered nature 10 years ago, recognizing that interventional radiologists need an office presence, time allocated to see patients, time to consult with referring physicians and time to see patients on the ward, said Stainken, an interventional radiologist at Roger Williams Medical Center in Providence, R.I. Reaffirmation of that policy came during ACR's 86th Annual Meeting and Chapter Leadership Conference May 5 in Washington, D.C.
The ACR policy support comes at a time when interventional radiologists have spent more than three decades working behind the scenes to solve the toughest medical problems, explained Stainken. "Interventional radiologists historically have worked on the sidelines as the 'specialists' specialist,' helping other doctors manage their patients with the most difficult problems—for example, working collaboratively with surgeons with trauma and transplant care," said Stainken. "While those physician relationships remain in place, interventional radiologists are taking positions in the front line of medical care. In delivering high-quality health care, interventional radiologists are formalizing their clinical role with offices, doing rounds and providing formalized consultation," added Stainken.
"As members of the medical house of radiology, interventional radiologists differ greatly from diagnostic radiologists. Interventional radiologists are hands-on clinicians—who are known as innovative problem solvers and critical resources in tough medical situations—and expert board-certified radiologists. Interventional radiologists are a dozen subspecialist doctors rolled into one," said Stainken.
According to the resolution, ACR "recognizes the importance of the development of a clinical service by interventional radiologists in order to appropriately manage patients." ACR, which "opposes any attempt to prohibit vascular and interventional radiologists from being granted admitting and other clinical privileges based solely on their designation as radiologists," affirmed the importance of vascular and interventional radiologists "establishing physician–patient relationships that are also customarily maintained by other physicians who provide comparable services."
ACR encourages and supports the establishment of interventional radiology clinical services within the practice of radiology groups, including establishment of an adequate clinical team; adequate space dedicated for clinical visits; inpatient admitting service; dedicated time for seeing inpatients and patients in a clinic; noninvasive vascular laboratory; clerical services for scheduling, insurance authorization and billing of procedures and evaluation/management services; and support for time and materials for promotional and educational efforts.
Sonography
Ultrasound Useful for Dense Breast Tissue
Mar. 25, 2009 (taken from ASRT site)
A new ultrasound breast scanner automatically acquires volume images of the breast and is ideally suited for cancer detection in women with dense breast tissue.
Research suggests that dense breast tissue is a risk factor for breast cancer. A 2007 New England Journal of Medicine study found that women with dense breast tissue had up to five times the risk of breast cancer compared to women with less dense breasts. Early detection in women with dense breast tissue is challenging because lesions can be harder to see on mammograms.
Ultrasound has shown promise as an adjunct to mammography in women with dense breast tissue. The Acuson S2000 Automated Breast Volume Scanner, or ABVS, will advance that promise, according to manufacturer Siemens Healthcare of Malvern, Pa.
ABVS is the first multiuse ultrasound breast system that automatically acquires volume images of the breast. The user independent, standardized image acquisition makes the system ideally suited for early detection and diagnosis of breast cancer with ultrasound.
ABVS quickly acquires and surveys full-field sonographic volume images for a more comprehensive overview of the breast. This overview includes the coronal plane of the breast from the nipple to the breast wall, which is not available with conventional ultrasound imaging. This view provides an improved representation of breast anatomy, according to Siemens.
The system offers improved workflow with its automatic image acquisition, while reducing examination and waiting time for the patient. Although hand held examinations usually take up to 30 minutes, clinicians using the ABVS can perform an exam in less than 15 minutes, according to Siemens. The system also has semiautomated reporting and comprehensive breast imaging reporting and data system capabilities.
"I am convinced that automatic ultrasound volume imaging with the Acuson S2000 ABVS can make a significant contribution in diagnostic confidence for women with dense breast tissue or inconclusive mammography findings," said Klaus Hambüchen, from Siemens Healthcare.
ABVS supports some of Siemens' innovative breast imaging applications, such as fatty tissue imaging technology, which increases detail and contrast resolution and improves boundary detection in fatty tissue. The system also supports eSie Touch elasticity imaging, which provides information on the mechanical properties of tissue for improved diagnostic capabilities.
Magnetic Resonance
Researchers Develop MR-Guided Catheters
Mar. 25, 2009 (from ASRT site)
Researchers have developed new guide wires for catheters that do not need x-rays or contrast medium and instead use magnetic resonance for guidance.
Catheters are important tools in many vascular examinations. For example, physicians will insert catheters into the groin or leg and thread it to the heart under x-ray guidance to examine the coronary arteries. A metal guide wire inside the catheter helps physicians steer and guide the catheter to its target. The addition of contrast media helps improve the view of the vascular system and the soft tissue on x-ray.
Risks in this procedure include exposure to both ionizing radiation, which is associated with an increased cancer risk, and a contrast agent, which can cause allergic reactions in some patients.
Researchers at the Fraunhofer Institute for Production Technology in Aachen, Germany, have found a way to avoid both the radiation and the contrast medium. Working with scientists from Philips Healthcare in Eindhoven, the Netherlands, and University Hospital in Aachen, they developed a guide wire made of glass-fiber-reinforced plastic.
One of the main challenges for the developers was avoiding the use of metal while keeping the guide wire extremely thin.
"Diameters of half a millimeter or less are required for the guide wires," noted Adrian Schütte, from the Fraunhofer Institute.
The researchers manufactured the guide wires through the process of pultrusion, which, as the name suggests, is a combination of pulling and extrusion. The process manufactures composite materials in such a way that reinforced fibers are pulled through a resin and into a heated die, where the resin is turned into a polymer.
"Because the guide wire is made of plastic, the imaging can be performed by magnetic resonance tomography instead of computer tomography," said Mr. Schütte. "This is not possible with metal guide wires, as the metal wire acts as an antenna and heats up too much; this would damage the vessels, and could cause proteins to clot."
Among MR's advantages is that it does not produce ionizing radiation and it enables views of soft tissue without requiring a contrast medium.
Researchers will present the new guide wires at the JEC trade fair in Paris from March 24 to March 26. The new wires will make their debut in hospitals within the next few months, according to the Fraunhofer Institute.
Radiology firm, doctors settle Medicare fraud case
Thursday, March 26, 2009
(03-26) 08:43 PDT Las Vegas, NV (AP) --
A Las Vegas radiology firm and its principals are agreeing to pay $2 million to resolve allegations that they submitted false or fraudulent federal Medicare claims.
The Department of Health and Human Services inspector general on Wednesday called the March 13 settlement with West Valley Imaging and doctors William Boren and Luke Cesaretti one of the largest ever reached.
Inspector General Daniel Levinson alleged Boren and Cesaretti and their firm improperly billed for diagnostic tests to Medicare beneficiaries and failed to provide required treating doctors' orders.
Levinson says the case was resolved with the financial penalty and a 5-year "integrity agreement."
The settlement included no finding of guilt, and the doctors did not admit wrongdoing.
Thursday, 26th March 2009
20 March 2009
By Richard Gladstone
Expansion of the Conquest Hospital's radiology department is now complete.
A rebuilding project has been carried out at the hospital and Eastbourne District General Hospital (DGH) over the last 12 months at a cost of £200,000 to allow more patients to be seen.
Ultrasound waits were at around ten weeks before the revamp but are now expected to be no more than three weeks for routine examinations thanks to the expansion.
Clare Parter, ultrasound services manager, said: "We are delighted with the work that has been done as it has greatly improved the working environment for staff and more importantly know that it will improve the patient experience with decreased waits and greater privacy.
"I would like to thank all the radiology department who have coped with the upheaval in the radiology department whilst the works have taken place."
A £120,000 rebuilding project at the Conquest has recently been completed involving the creation of a new suite to increase the number of scanning rooms from two to three.
It also provided a new reception and appointments office for the department, a dedicated scanning and waiting area for inpatients and a much-needed dedicated office area and reporting station for sonographers and consultant radiologists.
Ultrasound uses sound waves to image the inside of the body to allow doctors to diagnose and treat medical conditions.
Examinations are provided across a wide range of specialities and, using new fast-track clinics and systems of working, patients can be diagnosed quicker.
Tracking Increasing Use Of CT On Pregnant Women
Submitted by ruzik_tuzik on Mar 21st, 2009
Researchers have found that over a 10-year period radiologic exams on pregnant women have more than doubled, according to a study published in the online edition of Radiology.
"Imaging utilization has not been previously studied in the pregnant population," said Elizabeth Lazarus, M.D., assistant professor of diagnostic imaging at the Warren Alpert School of Medicine at Brown University and a radiologist at Rhode Island Hospital in Providence, R.I. "This population may be vulnerable to the adverse effects of radiation."
Dr. Lazarus and colleagues conducted a retrospective review of nuclear medicine, CT, fluoroscopy and plain-film x-ray imaging examinations performed at Rhode Island Hospital and Women and Infants' Hospital from 1997 through 2006 to determine how often these imaging exams were performed on pregnant women and the estimated radiation dose to the fetus. Data were then compared to the number of infant deliveries per year for that same time period.
The researchers found that from 1997 to 2006, the total number of imaging studies performed on pregnant women at their institution increased by 10.1 percent per year, but the number of CT exams increased by 25.3 percent per year. CT delivers a higher amount of radiation than many other radiologic procedures.
CT exams are not routinely ordered for pregnant women, but may be necessary to detect suspected life-threatening conditions such as bleeding in the brain, blood clots in the lungs or appendicitis. Since CT exposes the developing fetus to radiation, concerns are often raised regarding overuse. The majority of CT examinations (approximately 75 percent) analyzed in the study were performed in areas of the mother's body separate from the uterus, so the fetus was not exposed to any direct radiation. Still, low levels of radiation have been shown to carry a small risk of harm to a developing fetus.
"Women should know that imaging is generally safe during pregnancy and is often used to detect potentially life-threatening problems," Dr. Lazarus said. "However, this study should raise awareness about imaging trends in pregnant patients and help us continue in our efforts to minimize radiation exposure," Dr. Lazarus said.
The researchers evaluated 5,270 examinations on 3,285 patients. During the 10 years of the study, the number of patients imaged per year increased from 237 to 449, and the number of exams per year increased from 331 to 732. This represented an 89 percent increase in patients and a 121 percent increase in examinations over the course of the study. During the same 10 years, the number of deliveries only increased 7 percent from 8,661 to 9,264. Imaging utilization rates (exams per 1,000 deliveries) increased 107 percent.
Use of plain-film x-rays increased an average of 6.8 percent per year, and the number of nuclear medicine examinations rose by approximately 11.6 percent annually. Fluoroscopy utilization increased by 10.6 percent per year, and CT examinations increased by 25.3 percent per year.
A milliGray (mGy) is a unit of measure for absorbed radiation. The average estimated fetal radiation exposure per exam for CT was 4.3 mGy, compared to 2.91 mGy for fluoroscopy, 0.40 mGy for nuclear medicine and 0.43 mGy for x-rays.
Dr. Lazarus hopes that increased use of electronic medical records will help physicians and patients keep track of the number and types of imaging tests performed on pregnant women and give proper consideration to alternative imaging tests—such as MRI and ultrasound—that do not expose the patient or fetus to ionizing radiation.
Kaiser Daily Health Policy Report
Capitol Hill Watch | More Than 40 Lawmakers Sign Letter Asking CMS To Reverse Decision on Medicare Coverage for Virtual Colonoscopies
[Mar 17, 2009]
More than 40 members of Congress have signed a letter asking CMS to reverse its tentative decision to end Medicare coverage for virtual colonoscopies, or CT colonographies, CQ HealthBeat reports. CMS announced the decision on Feb. 11 based on a lack of evidence that virtual colonoscopies result in improved health for Medicare beneficiaries who do not have symptoms of and have average risk for colon cancer. CMS requested public comments on the decision.
The letter -- dated March 13 and signed by Reps. Kay Granger (R-Texas) and Patrick Kennedy (D-R.I.), among other lawmakers -- maintains that Medicare coverage for virtual colonoscopies could increase screening rates for colon cancer. According to the letter, screening rates for colon cancer increased by 70% at National Naval Medical Center after the center added virtual colonoscopies as an option for patients. Medicare coverage of virtual colonoscopies as a "minimally invasive screening test for colon cancer would not just encourage more patients to undergo screening, but it would potentially close or eliminate the gap in colorectal cancer screening between whites and minority populations," according to the letter.
CMS spokesperson Don McLeod said that the agency takes "all such letters very seriously" and plans to "respond to the members promptly" (Kim, CQ HealthBeat, 3/16).
Letter to the Editor
A Feb. 28 New York Times editorial praised the tentative decision by CMS, but agency officials should "reconsider their initial coverage denial for a screening tool that could contribute to saving both lives and health care dollars," Andrew Spiegel, CEO of the Colon Cancer Alliance; Ilyse Schuman, managing director of the Medical Imaging and Technology Alliance; and James Thrall, chair of the American College of Radiology Board of Chancellors, write in a Times letter to the editor. According to the authors, a clinical trial conducted in 2007 by the American College of Radiology Imaging Network involving more than 2,600 patients "demonstrated the clinical efficacy" of virtual colonoscopies and the "potential to enhance colon cancer screening compliance," and "it's been shown that virtual colonoscopy is less than half the cost of the optical test."
They add, "With less than half of all Americans 50 and older receiving colon cancer screening, Medicare's decision to deny the elderly access to virtual colonoscopy would maintain needless screening barriers that research proves disproportionately affect nonwhite and low-income Americans" (Spiegel et al., New York Times, 3/14).
Virtual colonoscopy
From Wikipedia, the free encyclopedia
Virtual colonoscopy (VC) is a medical imaging procedure which uses x-rays and computers to produce two- and three-dimensional images of the colon (large intestine) from the lowest part, the rectum, all the way to the lower end of the small intestine and display them on a screen. The procedure is used to diagnose colon and bowel disease, including polyps, diverticulosis and cancer. VC is performed via computed tomography (CT), sometimes called a CAT scan, or with magnetic resonance imaging (MRI).
Not to be confused with a similar procedure called a CT Pneumocolon, a virtual colonscopy can provide 3D reconstructed endoluminal views of the bowel.
While preparations for VC vary, the patient will usually be asked to take laxatives or other oral agents at home the day before the procedure to clear stool from the colon. A suppository is also used to cleanse the rectum of any remaining fecal matter. The patient is also given a solution designed to coat any residual faeces which may not have been cleared by the laxative. This is called 'faecal tagging'. This allows the user (usually a consultant radiologist), viewing the 3D images to effectively subtract the left over faeces, which may otherwise give false positive results.
VC takes place in the radiology department of a hospital or medical center. The examination takes about 10 minutes and does not require sedatives. During the procedure the patient is placed in a supine position on the examination table .
A thin tube is inserted into the rectum, so that air can be pumped through the tube in order to inflate the colon for better viewing.
The table moves through the scanner to produce a series of two-dimensional cross-sections along the length of the colon. A computer program puts these images together to create a three-dimensional picture that can be viewed on the video screen.
The patient is asked to hold his/her breath during the scan to avoid distortion on the images.
The scan is then repeated with the patient lying in a prone position.
After the examination, the images produced by the scanner must be processed into a 3D image, +/- a fly through (a cine program which allows the user move through the bowel as if performing a normal colonoscopy). A radiologist evaluates the results to identify any abnormalities.
The patient may resume normal activity after the procedure, but if abnormalities are found and the patient needs conventional colonoscopy, it may be performed the same day.
Advantages
VC is more comfortable than conventional colonoscopy for some people because it does not use a colonoscope. As a result, no sedation is needed, and the patient can return to his/her usual activities or go home after the procedure without the aid of another person. VC provides clearer, more detailed images than a conventional x-ray using a barium enema, sometimes called a lower gastrointestinal (GI) series. Further, about 1 in 10 patients will not have a complete right colon (cecum) evaluation completed with conventional colonoscopy.[ It also takes less time than either a conventional colonoscopy or a lower GI series.
VC provides a secondary benefit of revealing diseases or abnormalities outside the colon
Disadvantages
According to an article on niddk.nih.gov, the main disadvantage to VC is that a radiologist cannot take tissue samples (biopsy) or remove polyps during VC, so a conventional colonoscopy must be performed if abnormalities are found. Also, VC does not show as much detail as a conventional colonoscopy, so polyps smaller than between 2 and 10 millimeters in diameter may not show up on the images. Furthermore Virtual Colonoscopy performed with CT exposes the patient to ionizing radiation, however some research has demonstrated that ultra-low dose VC can be just as effective in demonstrating colon and bowel disease due to the great difference in x-ray absorption between air and the tissue comprising the inner wall of the colon.
Optical colonoscopy is taken as the "gold standard" for colorectal cancer screening by the vast majority of the medical and research communities. Some radiologists recommend VC as a preferred approach to colorectal screening. However, optical colonoscopy is considered the gold standard by some professionals because it permits complete visualization of the entire colon, hence providing the opportunity to identify precancerous polyps and cancer, and then to do diagnostic biopsies or therapeutic removal of these lesions, as soon as possible
News about Sonography, Ultrasound , ultrasound breast scanner, mammography, ABVS, Magnetic Resonance, MR-Guided Catheters, CT scanners, Virtual Colonoscopies, VC, Optical colonoscopy, CT exams, CT Pneumocolon & online radiology ce classes
Radiology
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News about Sonography, Ultrasound , ultrasound breast scanner, mammography, ABVS, Magnetic Resonance, MR-Guided Catheters, CT scanners, Virtual Colonoscopies, VC, Optical colonoscopy, CT exams, CT Pneumocolon & online radiology ce classes
